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000
FXUS61 KBOX 222145
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
445 PM EST SUN NOV 22 2009
.SYNOPSIS...
HIGH PRESSURE ACROSS THE SAINT LAWRENCE VALLEY WILL MOVE EAST OF
NOVA SCOTIA MONDAY. A LOW PRESSURE WILL APPROACH OUR REGION MONDAY
INTO TUESDAY. WEAK HIGH PRESSURE WILL BRIEFLY VISIT THE AREA TUESDAY
NIGHT INTO WEDNESDAY NIGHT...BEFORE ANOTHER LOW PRESSURE SYSTEM TRACKS
UP THE COAST LATER THURSDAY AND FRIDAY BRINGING THE CHANCE FOR
RAIN. COLD AND BLUSTERY WEATHER IS FORECAST BEHIND THE LOW ON
SATURDAY...WITH DRIER WEATHER FINISHING OFF NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
HIGH PRESSURE ACROSS THE SAINT LAWRENCE VALLEY THIS AFTERNOON WILL
MOVE TO NOVA SCOTIA OVERNIGHT. THIS WILL ALLOW NORTHEAST WINDS TO
BECOME MORE FROM THE EAST BY DAYBREAK. CURRENTLY WATCHING AN
EXPANSIVE AREA OF MARINE STRATUS ACROSS THE GULF OF MAINE AND GEORGES
BANK. LATEST VISIBLE IMAGERY SHOWING SOME OF THESE CLOUDS ARE DIURNAL
IN NATURE...AND SHOULD BRIEFLY DISSIPATE AROUND SUNSET...MAINLY
ACROSS THE INTERIOR.
HOWEVER...THE ONSHORE FLOW AND LOWERING TEMPERATURES WILL INCREASE
RELATIVE HUMIDITY AS THE EVENING WEARS ON. EXPECTING THESE LOWER
CLOUDS TO COME BACK LATE THIS EVENING AND LINGER THROUGH THE NIGHT.
SOME DRIZZLE IS POSSIBLE LATE TONIGHT...ESPECIALLY ALONG THE
IMMEDIATE COAST...BUT NOT OVERLY IMPRESSED WITH THE POTENTIAL.
A BLEND OF THE MAV/MET GUIDANCE LOOKS REASONABLE FOR TEMPERATURES.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
STILL SOME UNCERTAINTY WITH THE TRACK AND INTENSITY OF A LOW PRESSURE
MOVING NORTHEAST FROM THE MID ATLANTIC COAST MONDAY NIGHT. FOR
NOW...USED A BLEND OF THE GFS AND NAM TO MINIMIZE FORECAST ERROR.
22/15Z SREF MEAN IS EVEN SLOWER AND WEAKER AND SLOWER THAN THAT
SOLUTION.
MOST 22/12Z MODELS BRING SOME RAINFALL TO SOUTHERN NEW ENGLAND DURING
THE DAY MONDAY...ESPECIALLY DURING THE AFTERNOON. GIVEN THE
UNCERTAINTY IN THE MODEL TIMING...DID TREND THE ARRIVAL OF THIS
PRECIPITATION FASTER THAN PREVIOUS FORECAST. THINKING THE BEST CHANCE
FOR THE ARRIVAL OF THIS RAIN WILL BE MONDAY NIGHT.
USED A BLEND OF THE MAV/MET GUIDANCE ONCE MORE FOR TEMPERATURES
DURING THIS PORTION OF THE FORECAST.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
TUESDAY...LOW PRESSURE CENTER PROBABLY NEAR/SOUTH OF NANTUCKET 12Z
TUE THEN TRACKS GRADUALLY NORTHEASTWARD TOWARDS NOVA SCOTIA. NAM IS
A BIT WEAKER AND FURTHER INLAND THAN THE OTHER MODELS...TAKING LOW
OVER THE CAPE. FOR THIS PACKAGE GENERALLY LEANED TOWARDS THE
GFS/ECMWF/GGEM. STARTED OFF WITH CHANCE POPS OVER THE
INTERIOR...BUT STILL OPTED TO GO WITH LIKELY NEAR THE COAST. LOW
LEVEL MOISTURE SHOULD KEEP CLOUDS AROUND THROUGH THE DAY.
TUESDAY NIGHT/WEDNESDAY...LOW PRESSURE CONTINUES TO MOVE FURTHER
NORTH/EAST OF THE AREA...BEING REPLACED BY WEAK HIGH PRESSURE. NAM
INDICATES A LAYER OF LOW LEVEL MOISTURE JUST DEEP ENOUGH TO KEEP
CLOUDS AROUND FOR THESE 2 PERIODS...GFS MUCH DRIER. THINK THAT AT
LEAST SOME LOW LEVEL MOISTURE WILL LINGER...AND MID/HIGH CLOUDS
POSSIBLE WITH A SHORT WAVE. SO KEPT PARTLY TO MOSTLY CLOUDY SKIES IN
FORECAST. BUT LOW LEVEL MOISTURE LAYER LIKELY TOO THIN FOR MEASURABLE
PRECIP. TEMPERATURES ARE A BLEND OF MOS. CONTINUED WITH PREVIOUS
THINKING THAT WED WILL BE COOL AND RAW DURING THE AFTERNOON WITH
ONSHORE FLOW.
WEDNESDAY NIGHT THROUGH THANKSGIVING...MOSTLY CLOUDY SKIES/CHANCE
POPS DUE TO COMBINATION OF LOW LEVEL MOISTURE FROM EASTERLY FLOW AS
HIGH PRESSURE DEPARTS...AND AS LOW PRESSURE DEVELOPS OFF THE
CAROLINA COAST.
THURSDAY NIGHT THROUGH FRIDAY NIGHT...WENT WITH HPC GUIDANCE FOR
THIS PERIOD WITH A VIGOROUS LOW PRESSURE SYSTEM POTENTIALLY
AFFECTING OUR AREA. MODEL DISCREPANCIES EXIST...AS ECMWF AND GFS
SHOW SURFACE LOW TRACKING OVER SOUTHERN NEW ENGLAND BUT GGEM KEEPS
CENTER WELL TO THE SOUTH AND EAST. BUT AT THIS TIME HIGH CHANCE TO
LIKELY POPS SEEM PRUDENT FOR THU NIGHT THRU FRI. POSSIBILITY THAT
PRECIP COULD END AS A LIGHT RAIN/SNOW MIX FRI NIGHT IN INTERIOR AS
COLDER AIR SPILLS INTO THE AREA.
SATURDAY...POTENTIAL FOR BLUSTERY AND CHILLY WEATHER AS TIGHT
GRADIENT LINGERS WHILE SURFACE LOW PULLS TO THE NORTHEAST. BOTH
ECMWF AND GFS INDICATE A COLD POOL ALOFT AND LINGERING MOISTURE
WHICH COULD POTENTIALLY LEND ITSELF TO SOME SHOWERS. 1000-500 MB
THICKNESS ARE QUITE LOW...IF THIS SCENARIO PANS OUT CAN/T RULE OUT A
SOME SNOW SHOWERS IN THE FAR INTERIOR...BUT IT WOULD BE TOO WARM AT
THE SURFACE FOR ANY ACCUMULATION.
SUNDAY...HIGH PRESSURE WITH BELOW NORMAL TEMPS.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
THIS AFTERNOON...VFR WEST OF KMHT-KORH-KIJD. AREAS MVFR CIGS EAST OF
THAT LINE...ESPECIALLY EAST OF KLWM-KPVD-KMVY...DUE TO MARINE STRATUS
MOVING ONSHORE.
TONIGHT...BRIEF VFR POSSIBLE SHORTLY AFTER SUNSET ACROSS EASTERN MA
AND RI. MVFR CIGS MOVING IN FROM SOUTHEAST TO NORTHWEST OVERNIGHT.
MONDAY...EXPECT VFR CIGS MAINLY N OF ROUTE 2 ACROSS N MA...WHILE
CONDITIONS LOWER TO MVFR-IFR CIGS S OF THERE. LOCAL IFR CIGS ALONG
THE S COAST...CAPE COD AND THE ISLANDS DURING THE AFTERNOON. PATCHY
RAIN WILL APPROACH N CT/RI/SE MA DURING THE AFTERNOON WITH LOCAL
MVFR VSBYS.
MONDAY NIGHT...MVFR. AREAS OF IFR CONDITIONS IN LOW CLOUDS...RAIN
AND FOG...MAINLY EASTERN SECTIONS.
OUTLOOK /TUESDAY THROUGH FRIDAY/...
TUESDAY...MVFR WITH AREAS OF IFR IN LOW CLOUDS AND SCATTERED SHOWERS.
TUE NIGHT THROUGH THU...MVFR-IFR CONDITIONS MAY LINGER IN LOW
CLOUDS THROUGH THIS PERIOD. MAY HAVE AREAS OF DRIZZLE AND FOG
DEVELOPING LATER WED/WED NIGHT.
THU NIGHT AND FRI...LOW TO MEDIUM CONFIDENCE OF IFR CEILINGS AND
VSBYS IN SHOWERS.
&&
.MARINE...
NORTHEAST WINDS SHOULD SHIFT EAST OVERNIGHT. THE PERSISTENT ONSHORE
FLOW WILL CONTINUE TO BUILD SEAS OVERNIGHT ACROSS THE COASTAL WATERS
OF MA AND RI. A LOW PRESSURE MOVING NORTHEAST FROM THE MID ATLANTIC
COAST MONDAY AND MONDAY NIGHT WILL LIKELY INCREASE WINDS DURING THIS
TIME AS WELL. SMALL CRAFT ADVISORIES CONTINUE FOR MOST WATERS.
OUTLOOK /TUESDAY THROUGH FRIDAY/...
TUESDAY AND TUE NIGHT...SCA WINDS/SEAS LINGER TUE AS LOW PRESSURE TRACKS
TOWARDS NOVA SCOTIA. WINDS DIMINISH TUE NIGHT AND WED BUT SEAS WILL
BE SLOWER TO SUBSIDE.
WEDNESDAY THROUGH FRIDAY...PERSISTENT EASTERLY WINDS WILL
LIKELY CAUSE SEAS TO REMAIN ABOVE SCA THRESHOLDS ACROSS THE OUTER WATERS.
WINDS AND SEAS SHOULD INCREASE THANKSGIVING NIGHT AND FRIDAY IN
ADVANCE OF THE NEXT SYSTEM APPROACHING FROM THE SOUTH. POSSIBILITY OF
GALES FRI.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 5 AM TO 5 PM EST MONDAY FOR
ANZ232>235-237.
SMALL CRAFT ADVISORY UNTIL 5 PM EST MONDAY FOR ANZ250-254>256.
&&
$$
SYNOPSIS...BELK/NMB
NEAR TERM...BELK
SHORT TERM...BELK
LONG TERM...NMB
AVIATION...BELK/NMB
MARINE...BELK/NMB
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000
FXUS61 KOKX 222139
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
439 PM EST SUN NOV 22 2009
.SYNOPSIS...
AS STRONG HIGH PRESSURE REMAINS OVER NORTHERN NEW ENGLAND AND THE
CANADIAN MARITIMES...WEAK LOW PRESSURE WILL HEAD NORTHEAST JUST OFF
THE SOUTHEAST COAST TONIGHT THROUGH MONDAY...AND THEN PASS SOUTHEAST
OF LONG ISLAND MONDAY NIGHT AND SOUTH OF NOVA SCOTIA ON TUESDAY.
HIGH PRESSURE WILL BRIEFLY RETURN TUESDAY NIGHT INTO WEDNESDAY.
ANOTHER LOW WILL IMPACT THE AREA DURING THE SECOND HALF OF THE WORK
WEEK...WITH POSSIBLE IMPROVEMENT BY THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TRICKY FORECAST TONIGHT RE SKY COVER AND POTENTIAL FOR SOME LIGHT
RAIN OR DRIZZLE. PATCHES OF STRATOCU THAT MOVED WSW INTO CT AND LONG
ISLAND THIS AFTERNOON HAVE MOSTLY DISSIPATED...BUT WITH EVENTUAL
COOLING BENEATH A LOW LEVEL INVERSION THINK THEY WILL GAIN THE UPPER
HAND...ESPECIALLY AFTER MIDNIGHT. FORECAST SOUNDINGS ALSO SHOW
VEERING LOW LEVEL WIND PROFILES...INDICATIVE OF MODEST WARM AIR
ADVECTION AND POTENTIAL FOR ENOUGH LIFT TO GENERATE SOME LIGHT RAIN
OR DRIZZLE AFTER MIDNIGHT. E-NE WINDS STAYING UP TONIGHT SHOULD KEEP
RADIATIONAL COOLING AT BAY...WITH MINS AOA 12Z MAV GUIDANCE...WITH
MID/UPPER 30S WELL INLAND AND LOWER/MID 40S IN URBAN AND
COASTAL SECTIONS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
OPERATIONAL MODELS HAVE COME AROUND TO SOME AGREEMENT RE THE
EVENTUAL TRACK OF WEAK LOW PRESSURE DEVLOPING ALONG THE SOUTHEAST
COAST TONIGHT...AND MOVING SLOWLY UP THE COAST LATE TONIGHT THROUGH
TUE. THE 12Z GFS/RGEM/ECMWF WERE ALL IN GENERAL AGREEMENT...WITH THE
ECMWF JUST A TAD WEAKER/SLOWER...WHILE THE NAM WAS A BIT FARTHER
WEST. DISCOUNTED GEFS AND SREF MEAN SOLUTIONS AS THEY APPEARED TOO
SUPPRESSED...NOT GIVING ENOUGH CREDENCE TO REDEVELOPMENT OF THE LOW
FARTHER NORTHEAST LATE MON NIGHT AS AN UPPER TROUGH SWINGS TOWARD
THE MID ATLANTIC COAST. AS A RESULT SIDED WITH A SLIGHTLY SLOWER AND
WEAKER GFS SOLUTION WHICH CLOSELY PARALLELS THE ECMWF...WITH
INCREASING CHANCES FOR RAIN DURING MON ESPECIALLY IN THE
AFTERNOON...THEN CATEGORICAL POP WITH PERIODS OF MODERATE RAIN MON
NIGHT. FCST MODELS APPEAR TOO QUICK TO DRY THINGS OUT ON TUE...AND
THINK ENOUGH LOW LEVEL MOISTURE AND LIFT VIA CYCLONIC FLOW...EVEN
SOME MODEST OROGRAPHIC LIFT IN NORTHERLY FLOW ACROSS LONG ISLAND...
WILL HANG BACK TO PRODUCE MORE LIGHT RAIN/DRIZZLE THROUGH
TUE MORNING.
SKY COVER AND TEMPS ARE PROBLEMATIC FOR TUE NIGHT AS HIGH PRESSURE
BUILDS IN. SIDED WITH MORE CLOUD COVER AND MILDER TEMPS...BUT COULD
JUST AS EASILY ENVISION CLEARING SKIES...WITH BOTH LOWER TEMPS AND
SOME FOG VIA RADIATIONAL COOLING AND LINGERING GROUND MOISTURE. A
MOSTLY SUNNY DAY IS ON TAP FOR WED BEFORE THE NEXT SYSTEM BEGINS TO
ARRIVE WITH SOME LOW CHANCE POP LATE IN THE DAY OR DURING THE EARLY
EVENING.
FOR TEMPS...DURING THE PRECIP EVENT BLENDED 12Z MAV AND NAM 2M TEMPS
TO YIELD TEMPS COOLER THAN GUIDANCE. SIDED WITH TEMPS WARMER THAN
12Z MAV GUIDANCE TUE NIGHT...BUT CONFIDENCE IS LOW AS ALLUDED
TO ABOVE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
CLOSED LOW MOVES ACROSS THE GREAT LAKES REGION WEDNESDAY NIGHT AND
THURSDAY AS SFC LOW TRACKS JUST AHEAD OF IT. IT APPEARS AS THOUGH
UPSTREAM SHORTWAVE DIVES OUT OF CENTRAL CANADA...AND ROUNDS THE BASE
OF THIS LOW. AS SUCH...AMPLIFICATION OF THIS LOW TAKES PLACE AS IT
PLOWS TOWARD THE EAST COAST LATE IN THE WEEK. ONE WOULD EXPECT A SFC
LOW TO DEVELOP OFF THE SOUTHEAST/MID ATLC STATES AND MOVE NORTHWARD
TO A POSITION JUST OFF THE COAST. THIS LOW SHOULD BECOME PRIMARY LOW
IN TIME...WITH DEEPENING OCCURRING OVER NEW ENGLAND BY SATURDAY.
GGEM DOES NOT OFFER THIS SCENARIO...WITH NOT MUCH COASTAL
DEVELOPMENT EVIDENT.
AS SUCH...GLOBAL MODELS OFFER SOME DIFFERENCES WITH HANDLING OF THIS
COMPLEX SYSTEM THAT WILL IMPACT THE NORTHEAST THROUGH MUCH OF THIS
TIME FRAME. EXACT DETAILS STILL HAZY...AND EC/HPC FOLLOWED THIS TIME
FRAME.
WOULD EXPECT AN INCREASE IN POPS WED NIGHT AND THURSDAY...ALTHOUGH
WIDESPREAD QPF NOT ANTICIPATED QUITE YET. RAIN CHANCES WOULD
CONTINUE FRIDAY...WITH POSSIBLE IMPROVEMENT BY THE WEEKEND AS DEEPER
NORTHWEST FLOW TAKES HOLD. COULD BE WINDY THOUGH BEHIND THIS SYSTEM
AS THE SFC LOW PASSES NORTH AND UPPER LOW MOVES EAST. LINGERING
INSTABILITY POPS WARRANTED INTO SAT...WITH DRYING THEREAFTER.
AS FOR ANY MIXED PRECIP...IT WILL BE COLD ALOFT BY THE WEEKEND (FRI
NIGHT AND SAT) AS UPPER COLD POOL MOVES OVERHEAD. ANY SNOW MENTION
WILL DEPEND ON BOUNDARY LAYER TEMPS IN DATABASE THIS TIME FRAME.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
VFR THROUGH THIS AFTERNOON...ALTHOUGH CEILINGS MAY DEVELOP EARLY
THIS EVENING. THICK ST/SC DECK OVER EASTERN LONG ISLAND IS INCHING
WESTWARD. TENDRELS OF ST ALSO DEVELOPING OVER LONG ISLAND SOUND.
MVFR CIGS ARE POSSIBLE AFTER ABOUT 21Z...BUT WILL NEED TO MONITOR
SAT TRENDS TO NAIL DOWN TIMING AND INCLUDE IN TAFS.
ONCE CIGS DEVELOP...THEY SHOULD REMAIN IN PLACE OVERNIGHT.
WIND DIRECTIONS MAY VARY FROM 350 TO 060 THIS AFTERNOON...BUT THE
GENERAL TREND WILL BE SHIFTING TOWARD THE EAST.
OUTLOOK 18Z MONDAY THROUGH THURSDAY...
MONDAY THRU TUESDAY PM...SUB-VFR...PDS OF IFR LIKELY. GUSTY E-NE
WINDS.
TUESDAY NIGHT...BECOMING VFR.
WEDNESDAY...VFR.
WEDNESDAY NIGHT-THURSDAY ...SUB-VFR POSSIBLE.
&&
.MARINE...
HAVE STARTED SCA RIGHT OFF THE BAT FOR ALL OCEAN ZONES. WINDS/SEAS
JUST SHY OF CRITERIA ATTM...BUT SHOULD RAMP ABOVE THIS EVENING AS
PRES GRADIENT CONTINUES TO TIGHTEN UP BETWEEN HIGH PRESSURE TO THE
NORTH...AND A DEVELOPING COASTAL LOW. QUIET CONDITIONS ON THE
SOUDFN/HARBOR/BAYS ARE LIKELY TO CONTINUE LONGER...SO DELAYED SCA
START TIME THERE UNTIL MIDNIGHT.
E-NE FLOW WITH SCA CONDITIONS LIKELY TO CONTINUE ON ALL WATERS
THROUGH MON NIGHT...WITH MAX OCEAN SEAS 9 OR 10 FT...JUST SHY OF
WAVEWATCH VALUES. GALES UNLIKELY TO OCCUR...BUT IT COULD BE A CLOSE
CALL ON THE FAR EASTERN OCEAN WATERS LATE MON NIGHT OR EARLY TUE
MORNING AS THE COASTAL LOW PASSES BY. PROBABILITY OF GALES LESS THAN
50 PERCENT ATTM...SO DID NOT ISSUE A WATCH.
SCA CONDITIONS SHOULD CONTINUE ON THE OCEAN AT LEAST THROUGH THE DAY
ON TUE AND POSSIBLY INTO TUE NIGHT...WITH WINDS DIMINISHING BUT SEAS
SLOW TO SUBSIDE AFTER THE LOW PASSES. SCA CONDITIONS MAY ALSO
CONTINUE AT LEAST INTO TUE MORNING ON THE EASTERN SOUND/BAYS.
WINDS BACK TO THE SOUTHEAST WED NIGHT...AND EAST THURSDAY AS INLAND
LOW/FRONT NEARS. IF COASTAL LOW DEVELOPS OFF SE/MID ATLC COAST LATER
THURSDAY AND FRIDAY...WOULD SEE AN INCREASE IN WINDS AS THEY BACK TO
THE NORTH. WINDS BACK FURTHER TO THE WEST/NW FRIDAY AND SATURDAY AS
THE LOW DEEPENS AND TRACKS JUST TO THE NORTH. SPEEDS WILL PICK UP
QUITE A BIT.
A GRADUAL INCREASE IN SEAS EXPECTED THURSDAY AND FRIDAY AS COASTAL
LOW IMPACTS THE AREA WATERS. WAVE WATCH III OUTPUT SEEMS REASONABLE.
EASTERN WATERS ON FRIDAY WILL OBSERVE HIGHEST SEAS DUE TO STRONG
WEST FETCH.
&&
.HYDROLOGY...
QPF FOR THE UPCOMING EVENT CALLS FOR 1/2 INCH MOST OF THE AREA...AND
1/2 TO 3/4 INCH ACROSS SOUTHEAST CT AND EASTER LONG ISLAND.
ADDITIONAL PRECIPITATION IS POSSIBLE THU AND FRI. NO HYDROLOGIC
PROBLEMS ARE ANTICIPATED.
&&
.TIDES/COASTAL FLOODING...
36 TO 48 HOUR PERIOD OF E-NE WINDS EXPECTED TO RESULT IN WATER
LEVELS AROUND 2 FT ABOVE NORMAL. THE CURRENT TIDE CYCLES ARE
INCREASING...BUT ARE NOT AT ASTRONOMICAL HIGHS UNTIL NEXT WEEK.
BASED ON CURRENT LEVELS...2.5 TO 3 FT IS NEEDED FOR MINOR FLOODING
FOR BOTH MONDAY AFTERNOON AND TUESDAY AFTERNOON HIGH TIDE CYCLES.
THEREFORE NO PRODUCTS WILL BE ISSUED AT THIS TIME. THE SITUATION
WILL BE MONITORED CLOSELY.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM EST TUESDAY
FOR ANZ330-335-338-340-345.
SMALL CRAFT ADVISORY UNTIL 6 PM EST TUESDAY FOR ANZ350-353-355.
&&
$$
SYNOPSIS...BG
NEAR TERM...BG
SHORT TERM...BG
LONG TERM...PW
AVIATION...BS
MARINE...BG/PW
HYDROLOGY...BG
TIDES/COASTAL FLOODING...BS
000
FXUS61 KOKX 222135
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
435 PM EST SUN NOV 22 2009
.SYNOPSIS...
AS STRONG HIGH PRESSURE REMAINS OVER NORTHERN NEW ENGLAND AND THE
CANADIAN MARITIMES...WEAK LOW PRESSURE WILL HEAD NORTHEAST JUST OFF
THE SOUTHEAST COAST TONIGHT THROUGH MONDAY...AND THEN PASS SOUTHEAST
OF LONG ISLAND MONDAY NIGHT AND SOUTH OF NOVA SCOTIA ON TUESDAY.
HIGH PRESSURE WILL BRIEFLY RETURN TUESDAY NIGHT INTO WEDNESDAY.
ANOTHER LOW WILL IMPACT THE AREA DURING THE SECOND HALF OF THE WORK
WEEK...WITH POSSIBLE IMPROVEMENT BY THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TRICKY FORECAST TONIGHT RE SKY COVER AND POTENTIAL FOR SOME LIGHT
RAIN OR DRIZZLE. PATCHES OF STRATOCU THAT MOVED WSW INTO CT AND LONG
ISLAND THIS AFTERNOON HAVE MOSTLY DISSIPATED...BUT WITH EVENTUAL
COOLING BENEATH A LOW LEVEL INVERSION THINK THEY WILL GAIN THE UPPER
HAND...ESPECIALLY AFTER MIDNIGHT. FORECAST SOUNDINGS ALSO SHOW
VEERING LOW LEVEL WIND PROFILES...INDICATIVE OF MODEST WARM AIR
ADVECTION AND POTENTIAL FOR ENOUGH LIFT TO GENERATE SOME LIGHT RAIN
OR DRIZZLE AFTER MIDNIGHT. E-NE WINDS STAYING UP TONIGHT SHOULD KEEP
RADIATIONAL COOLING AT BAY...WITH MINS AOA 12Z MAV GUIDANCE...WITH
MID/UPPER 30S WELL INLAND AND LOWER/MID 40S IN URBAN AND
COASTAL SECTIONS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
OPERATIONAL MODELS HAVE COME AROUND TO SOME AGREEMENT RE THE
EVENTUAL TRACK OF WEAK LOW PRESSURE DEVLOPING ALONG THE SOUTHEAST
COAST TONIGHT...AND MOVING SLOWLY UP THE COAST LATE TONIGHT THROUGH
TUE. THE 12Z GFS/RGEM/ECMWF WERE ALL IN GENERAL AGREEMENT...WITH THE
ECMWF JUST A TAD WEAKER/SLOWER...WHILE THE NAM WAS A BIT FARTHER
WEST. DISCOUNTED GEFS AND SREF MEAN SOLUTIONS AS THEY APPEARED TOO
SUPPRESSED...NOT GIVING ENOUGH CREDENCE TO REDEVELOPMENT OF THE LOW
FARTHER NORTHEAST LATE MON NIGHT AS AN UPPER TROUGH SWINGS TOWARD
THE MID ATLANTIC COAST. AS A RESULT SIDED WITH A SLIGHTLY SLOWER AND
WEAKER GFS SOLUTION WHICH CLOSELY PARALLELS THE ECMWF...WITH
INCREASING CHANCES FOR RAIN DURING MON ESPECIALLY IN THE
AFTERNOON...THEN CATEGORICAL POP WITH PERIODS OF MODERATE RAIN MON
NIGHT. FCST MODELS APPEAR TOO QUICK TO DRY THINGS OUT ON TUE...AND
THINK ENOUGH LOW LEVEL MOISTURE AND LIFT VIA CYCLONIC FLOW...EVEN
SOME MODEST OROGRAPHIC LIFT IN NORTHERLY FLOW ACROSS LONG ISLAND...
WILL HANG BACK TO PRODUCE MORE LIGHT RAIN/DRIZZLE THROUGH
TUE MORNING.
SKY COVER AND TEMPS ARE PROBLEMATIC FOR TUE NIGHT AS HIGH PRESSURE
BUILDS IN. SIDED WITH MORE CLOUD COVER AND MILDER TEMPS...BUT COULD
JUST AS EASILY ENVISION CLEARING SKIES...WITH BOTH LOWER TEMPS AND
SOME FOG VIA RADIATIONAL COOLING AND LINGERING GROUND MOISTURE. A
MOSTLY SUNNY DAY IS ON TAP FOR WED BEFORE THE NEXT SYSTEM BEGINS TO
ARRIVE WITH SOME LOW CHANCE POP LATE IN THE DAY OR DURING THE EARLY
EVENING.
FOR TEMPS...DURING THE PRECIP EVENT BLENDED 12Z MAV AND NAM 2M TEMPS
TO YIELD TEMPS COOLER THAN GUIDANCE. SIDED WITH TEMPS WARMER THAN
12Z MAV GUIDANCE TUE NIGHT...BUT CONFIDENCE IS LOW AS ALLUDED
TO ABOVE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
CLOSED LOW MOVES ACROSS THE GREAT LAKES REGION WEDNESDAY NIGHT AND
THURSDAY AS SFC LOW TRACKS JUST AHEAD OF IT. IT APPEARS AS THOUGH
UPSTREAM SHORTWAVE DIVES OUT OF CENTRAL CANADA...AND ROUNDS THE BASE
OF THIS LOW. AS SUCH...AMPLIFICATION OF THIS LOW TAKES PLACE AS IT
PLOWS TOWARD THE EAST COAST LATE IN THE WEEK. ONE WOULD EXPECT A SFC
LOW TO DEVELOP OFF THE SOUTHEAST/MID ATLC STATES AND MOVE NORTHWARD
TO A POSITION JUST OFF THE COAST. THIS LOW SHOULD BECOME PRIMARY LOW
IN TIME...WITH DEEPENING OCCURRING OVER NEW ENGLAND BY SATURDAY.
GGEM DOES NOT OFFER THIS SCENARIO...WITH NOT MUCH COASTAL
DEVELOPMENT EVIDENT.
AS SUCH...GLOBAL MODELS OFFER SOME DIFFERENCES WITH HANDLING OF THIS
COMPLEX SYSTEM THAT WILL IMPACT THE NORTHEAST THROUGH MUCH OF THIS
TIME FRAME. EXACT DETAILS STILL HAZY...AND EC/HPC FOLLOWED THIS TIME
FRAME.
WOULD EXPECT AN INCREASE IN POPS WED NIGHT AND THURSDAY...ALTHOUGH
WIDESPREAD QPF NOT ANTICIPATED QUITE YET. RAIN CHANCES WOULD
CONTINUE FRIDAY...WITH POSSIBLE IMPROVEMENT BY THE WEEKEND AS DEEPER
NORTHWEST FLOW TAKES HOLD. COULD BE WINDY THOUGH BEHIND THIS SYSTEM
AS THE SFC LOW PASSES NORTH AND UPPER LOW MOVES EAST. LINGERING
INSTABILITY POPS WARRANTED INTO SAT...WITH DRYING THEREAFTER.
AS FOR ANY MIXED PRECIP...IT WILL BE COLD ALOFT BY THE WEEKEND (FRI
NIGHT AND SAT) AS UPPER COLD POOL MOVES OVERHEAD. ANY SNOW MENTION
WILL DEPEND ON BOUNDARY LAYER TEMPS IN DATABASE THIS TIME FRAME.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
VFR THROUGH THIS AFTERNOON...ALTHOUGH CEILINGS MAY DEVELOP EARLY
THIS EVENING. THICK ST/SC DECK OVER EASTERN LONG ISLAND IS INCHING
WESTWARD. TENDRELS OF ST ALSO DEVELOPING OVER LONG ISLAND SOUND.
MVFR CIGS ARE POSSIBLE AFTER ABOUT 21Z...BUT WILL NEED TO MONITOR
SAT TRENDS TO NAIL DOWN TIMING AND INCLUDE IN TAFS.
ONCE CIGS DEVELOP...THEY SHOULD REMAIN IN PLACE OVERNIGHT.
WIND DIRECTIONS MAY VARY FROM 350 TO 060 THIS AFTERNOON...BUT THE
GENERAL TREND WILL BE SHIFTING TOWARD THE EAST.
OUTLOOK 18Z MONDAY THROUGH THURSDAY...
MONDAY THRU TUESDAY PM...SUB-VFR...PDS OF IFR LIKELY. GUSTY E-NE
WINDS.
TUESDAY NIGHT...BECOMING VFR.
WEDNESDAY...VFR.
WEDNESDAY NIGHT-THURSDAY ...SUB-VFR POSSIBLE.
&&
.MARINE...
HAVE STARTED SCA RIGHT OFF THE BAT FOR ALL OCEAN ZONES. WINDS/SEAS
JUST SHY OF CRITERIA ATTM...BUT SHOULD RAMP ABOVE THIS EVENING AS
PRES GRADIENT CONTINUES TO TIGHTEN UP BETWEEN HIGH PRESSURE TO THE
NORTH...AND A DEVELOPING COASTAL LOW. QUIET CONDITIONS ON THE
SOUDFN/HARBOR/BAYS ARE LIKELY TO CONTINUE LONGER...SO DELAYED SCA
START TIME THERE UNTIL MIDNIGHT.
E-NE FLOW WITH SCA CONDITIONS LIKELY TO CONTINUE ON ALL WATERS
THROUGH MON NIGHT...WITH MAX OCEAN SEAS 9 OR 10 FT...JUST SHY OF
WAVEWATCH VALUES. GALES UNLIKELY TO OCCUR...BUT IT COULD BE A CLOSE
CALL ON THE FAR EASTERN OCEAN WATERS LATE MON NIGHT OR EARLY TUE
MORNING AS THE COASTAL LOW PASSES BY. PROBABILITY OF GALES LESS THAN
50 PERCENT ATTM...SO DID NOT ISSUE A WATCH.
SCA CONDITIONS SHOULD CONTINUE ON THE OCEAN AT LEAST THROUGH THE DAY
ON TUE AND POSSIBLY INTO TUE NIGHT...WITH WINDS DIMINISHING BUT SEAS
SLOW TO SUBSIDE AFTER THE LOW PASSES. SCA CONDITIONS MAY ALSO
CONTINUE AT LEAST INTO TUE MORNING ON THE EASTERN SOUND/BAYS.
WINDS BACK TO THE SOUTHEAST WED NIGHT...AND EAST THURSDAY AS INLAND
LOW/FRONT NEARS. IF COASTAL LOW DEVELOPS OFF SE/MID ATLC COAST LATER
THURSDAY AND FRIDAY...WOULD SEE AN INCREASE IN WINDS AS THEY BACK TO
THE NORTH. WINDS BACK FURTHER TO THE WEST/NW FRIDAY AND SATURDAY AS
THE LOW DEEPENS AND TRACKS JUST TO THE NORTH. SPEEDS WILL PICK UP
QUITE A BIT.
A GRADUAL INCREASE IN SEAS EXPECTED THURSDAY AND FRIDAY AS COASTAL
LOW IMPACTS THE AREA WATERS. WAVE WATCH III OUTPUT SEEMS REASONABLE.
EASTERN WATERS ON FRIDAY WILL OBSERVE HIGHEST SEAS DUE TO STRONG
WEST FETCH.
&&
.HYDROLOGY...
QPF FOR THE UPCOMING EVENT CALLS FOR 1/2 INCH MOST OF THE AREA...AND
1/2 TO 3/4 INCH ACROSS SOUTHEAST CT AND EASTER LONG ISLAND.
ADDITIONAL PRECIPITATION IS POSSIBLE THU AND FRI. NO HYDROLOGIC
PROBLEMS ARE ANTICIPATED.
&&
.TIDES/COASTAL FLOODING...
DEPARTURES OF 2.0-2.5 FT AND 2.5-3.0 FT ARE NEEDED FOR THE
HIGHER/LOWER HIGH TIDE CYCLES ON MON/TUE TO PRODUCE MINOR COASTAL
FLOODING. CURRENT GUIDANCE FORECASTS DEPARTURES OF 0.5-1.0 FT...BUT
IS BASED ON A TRACK THAT BOTH FASTER AND FARTHER OUT TO SEA THAN
CURRENT THINKING. EVEN SO...A SLOWER/CLOSER LOW TRACK MAY STILL NOT
PRODUCE DEPARTURES LARGE ENOUGH TO CAUSE COASTAL FLOODING. THIS WILL
CONTINUE TO BE MONITORED CLOSELY.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM EST
TUESDAY FOR ANZ330-335-338-340-345.
SMALL CRAFT ADVISORY UNTIL 6 PM EST TUESDAY FOR ANZ350-353-355.
&&
$$
SYNOPSIS / NEAR TERM / SHORT TERM / HYDROLOGY...GOODMAN
LONG TERM...PW
AVIATION / TIDES/COASTAL FLOODING...BS
MARINE...GOODMAN/PW
000
FXUS61 KBOX 222125
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
425 PM EST SUN NOV 22 2009
.SYNOPSIS...
HIGH PRESSURE ACROSS THE SAINT LAWRENCE VALLEY WILL MOVE EAST OF
NOVA SCOTIA MONDAY. A LOW PRESSURE WILL APPROACH OUR REGION MONDAY
INTO TUESDAY. WEAK HIGH PRESSURE WILL BRIEFLY VISIT THE AREA TUESDAY
NIGHT INTO WEDNESDAY NIGHT...BEFORE ANOTHER LOW PRESSURE SYSTEM TRACKS
UP THE COAST LATER THURSDAY AND FRIDAY BRINGING THE CHANCE FOR
RAIN. COLD AND BLUSTERY WEATHER IS FORECAST BEHIND THE LOW ON
SATURDAY...WITH DRIER WEATHER FINISHING OFF NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
HIGH PRESSURE ACROSS THE SAINT LAWRENCE VALLEY THIS AFTERNOON WILL
MOVE TO NOVA SCOTIA OVERNIGHT. THIS WILL ALLOW NORTHEAST WINDS TO
BECOME MORE FROM THE EAST BY DAYBREAK. CURRENTLY WATCHING AN
EXPANSIVE AREA OF MARINE STRATUS ACROSS THE GULF OF MAINE AND GEORGES
BANK. LATEST VISIBLE IMAGERY SHOWING SOME OF THESE CLOUDS ARE DIURNAL
IN NATURE...AND SHOULD BRIEFLY DISSIPATE AROUND SUNSET...MAINLY
ACROSS THE INTERIOR.
HOWEVER...THE ONSHORE FLOW AND LOWERING TEMPERATURES WILL INCREASE
RELATIVE HUMIDITY AS THE EVENING WEARS ON. EXPECTING THESE LOWER
CLOUDS TO COME BACK LATE THIS EVENING AND LINGER THROUGH THE NIGHT.
SOME DRIZZLE IS POSSIBLE LATE TONIGHT...ESPECIALLY ALONG THE
IMMEDIATE COAST...BUT NOT OVERLY IMPRESSED WITH THE POTENTIAL.
A BLEND OF THE MAV/MET GUIDANCE LOOKS REASONABLE FOR TEMPERATURES.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
STILL SOME UNCERTAINTY WITH THE TRACK AND INTENSITY OF A LOW PRESSURE
MOVING NORTHEAST FROM THE MID ATLANTIC COAST MONDAY NIGHT. FOR
NOW...USED A BLEND OF THE GFS AND NAM TO MINIMIZE FORECAST ERROR.
22/15Z SREF MEAN IS EVEN SLOWER AND WEAKER AND SLOWER THAN THAT
SOLUTION.
MOST 22/12Z MODELS BRING SOME RAINFALL TO SOUTHERN NEW ENGLAND DURING
THE DAY MONDAY...ESPECIALLY DURING THE AFTERNOON. GIVEN THE
UNCERTAINTY IN THE MODEL TIMING...DID TREND THE ARRIVAL OF THIS
PRECIPITATION FASTER THAN PREVIOUS FORECAST. THINKING THE BEST CHANCE
FOR THE ARRIVAL OF THIS RAIN WILL BE MONDAY NIGHT.
USED A BLEND OF THE MAV/MET GUIDANCE ONCE MORE FOR TEMPERATURES
DURING THIS PORTION OF THE FORECAST.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
TUESDAY...LOW PRESSURE CENTER PROBABLY NEAR/SOUTH OF NANTUCKET 12Z
TUE THEN TRACKS GRADUALLY NORTHEASTWARD TOWARDS NOVA SCOTIA. NAM IS
A BIT WEAKER AND FURTHER INLAND THAN THE OTHER MODELS...TAKING LOW
OVER THE CAPE. FOR THIS PACKAGE GENERALLY LEANED TOWARDS THE
GFS/ECMWF/GGEM. STARTED OFF WITH CHANCE POPS OVER THE
INTERIOR...BUT STILL OPTED TO GO WITH LIKELY NEAR THE COAST. LOW
LEVEL MOISTURE SHOULD KEEP CLOUDS AROUND THROUGH THE DAY.
TUESDAY NIGHT/WEDNESDAY...LOW PRESSURE CONTINUES TO MOVE FURTHER
NORTH/EAST OF THE AREA...BEING REPLACED BY WEAK HIGH PRESSURE. QUITE
A DIFFERENCE BETWEEN NAM AND GFS AS NAM INDICATES A LAYER OF LOW
LEVEL MOISTURE JUST DEEP ENOUGH TO KEEP CLOUDS AROUND FOR THESE 2
PERIODS...GFS MUCH DRIER. THINK THAT AT LEAST SOME LOW LEVEL
MOISTURE WILL LINGER...AT THIS TIME WILL KEEP PARTLY TO MOSTLY
CLOUDY SKIES IN FORECAST...ALSO KEEPING IN MIND GFS INDICATES A
SHORT WAVE. BUT LOW LEVEL LAYER LIKELY TOO THIN FOR MEASURABLE
PRECIP. TEMPERATURES ARE A BLEND OF MOS. CONTINUED WITH PREVIOUS
THINKING THAT WED WILL BE COOL AND RAW DURING THE AFTERNOON WITH
ONSHORE FLOW.
WEDNESDAY NIGHT THROUGH THANKSGIVING...MOSTLY CLOUDY SKIES/CHANCE
POPS DUE TO COMBINATION OF LOW LEVEL MOISTURE FROM EASTERLY FLOW AS
HIGH PRESSURE DEPARTS...AND AS LOW PRESSURE DEVELOPS OFF THE
CAROLINA COAST.
THURSDAY NIGHT THROUGH FRIDAY NIGHT...WENT WITH HPC GUIDANCE FOR
THIS PERIOD WITH A VIGOROUS LOW PRESSURE SYSTEM POTENTIALLY
AFFECTING OUR AREA. MODEL DISCREPANCIES EXIST...AS ECMWF AND GFS
SHOW SURFACE LOW TRACKING OVER SOUTHERN NEW ENGLAND BUT GGEM KEEPS
CENTER WELL TO THE SOUTH AND EAST. BUT AT THIS TIME HIGH CHANCE TO
LIKELY POPS SEEM PRUDENT FOR THU NIGHT THRU FRI. POSSIBILITY THAT
PRECIP COULD END AS A LIGHT RAIN/SNOW MIX FRI NIGHT IN INTERIOR AS
COLDER AIR SPILLS INTO THE AREA.
SATURDAY...POTENTIAL FOR BLUSTERY AND CHILLY WEATHER AS TIGHT
GRADIENT LINGERS WHILE SURFACE LOW PULLS TO THE NORTHEAST. BOTH
ECMWF AND GFS INDICATE A COLD POOL ALOFT AND LINGERING MOISTURE
WHICH COULD POTENTIALLY LEND ITSELF TO SOME SHOWERS. 1000-500 MB
THICKNESS ARE QUITE LOW...IF THIS SCENARIO PANS OUT CAN/T RULE OUT A
SOME SNOW SHOWERS IN THE FAR INTERIOR...BUT IT WOULD BE TOO WARM AT
THE SURFACE FOR ANY ACCUMULATION.
SUNDAY...HIGH PRESSURE WITH BELOW NORMAL TEMPS.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
THIS AFTERNOON...VFR WEST OF KMHT-KORH-KIJD. AREAS MVFR CIGS EAST OF
THAT LINE...ESPECIALLY EAST OF KLWM-KPVD-KMVY...DUE TO MARINE STRATUS
MOVING ONSHORE.
TONIGHT...BRIEF VFR POSSIBLE SHORTLY AFTER SUNSET ACROSS EASTERN MA
AND RI. MVFR CIGS MOVING IN FROM SOUTHEAST TO NORTHWEST OVERNIGHT.
MONDAY...EXPECT VFR CIGS MAINLY N OF ROUTE 2 ACROSS N MA...WHILE
CONDITIONS LOWER TO MVFR-IFR CIGS S OF THERE. LOCAL IFR CIGS ALONG
THE S COAST...CAPE COD AND THE ISLANDS DURING THE AFTERNOON. PATCHY
RAIN WILL APPROACH N CT/RI/SE MA DURING THE AFTERNOON WITH LOCAL
MVFR VSBYS.
MONDAY NIGHT...MVFR. AREAS OF IFR CONDITIONS IN LOW CLOUDS...RAIN
AND FOG...MAINLY EASTERN SECTIONS.
OUTLOOK /TUESDAY THROUGH FRIDAY/...
TUESDAY...MVFR WITH AREAS OF IFR IN LOW CLOUDS AND SCATTERED SHOWERS.
TUE NIGHT THROUGH THU...MVFR-IFR CONDITIONS MAY LINGER IN LOW
CLOUDS THROUGH THIS PERIOD. MAY HAVE AREAS OF DRIZZLE AND FOG
DEVELOPING LATER WED/WED NIGHT.
THU NIGHT AND FRI...LOW TO MEDIUM CONFIDENCE OF IFR CEILINGS AND
VSBYS IN SHOWERS.
&&
.MARINE...
NORTHEAST WINDS SHOULD SHIFT EAST OVERNIGHT. THE PERSISTENT ONSHORE
FLOW WILL CONTINUE TO BUILD SEAS OVERNIGHT ACROSS THE COASTAL WATERS
OF MA AND RI. A LOW PRESSURE MOVING NORTHEAST FROM THE MID ATLANTIC
COAST MONDAY AND MONDAY NIGHT WILL LIKELY INCREASE WINDS DURING THIS
TIME AS WELL. SMALL CRAFT ADVISORIES CONTINUE FOR MOST WATERS.
OUTLOOK /TUESDAY THROUGH FRIDAY/...
TUESDAY AND TUE NIGHT...SCA WINDS/SEAS LINGER TUE AS LOW PRESSURE TRACKS
TOWARDS NOVA SCOTIA. WINDS DIMINISH TUE NIGHT AND WED BUT SEAS WILL
BE SLOWER TO SUBSIDE.
WEDNESDAY THROUGH FRIDAY...PERSISTENT EASTERLY WINDS WILL
LIKELY CAUSE SEAS TO REMAIN ABOVE SCA THRESHOLDS ACROSS THE OUTER WATERS.
WINDS AND SEAS SHOULD INCREASE THANKSGIVING NIGHT AND FRIDAY IN
ADVANCE OF THE NEXT SYSTEM APPROACHING FROM THE SOUTH. POSSIBILITY OF
GALES FRI.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 5 AM TO 5 PM EST MONDAY FOR
ANZ232>235-237.
SMALL CRAFT ADVISORY UNTIL 5 PM EST MONDAY FOR ANZ250-254>256.
&&
$$
SYNOPSIS...BELK/NMB
NEAR TERM...BELK
SHORT TERM...BELK
LONG TERM...NMB
AVIATION...BELK/NMB
MARINE...BELK/NMB
[top]
000
FXUS61 KALY 222108
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
408 PM EST SUN NOV 22 2009
.SYNOPSIS...
HIGH PRESSURE OVER THE CANADIAN MARITIMES THIS EVENING
WILL CONTINUE TO DRIFT NORTHEAST TONIGHT...AS A LOW PRESSURE SYSTEM
ALONG THE CAROLINA COAST STARTS TO MOVE NORTHEASTWARD. THIS LOW
PRESSURE SYSTEM WILL PASS FAR EAST OF CAPE COD ON TUESDAY...
RESULTING IN MAINLY LIGHT PRECIPITATION ACROSS MUCH OF OUR REGION
MONDAY NIGHT INTO TUESDAY. A SERIES OF MUCH STRONGER STORMS WILL
IMPACT OUR REGION LATER IN THE WEEK...RESULTING IN UNSETTLED WEATHER
FROM THANKSGIVING THROUGH MUCH OF THE HOLIDAY WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
CLOUDS HAVE FINALLY DISSIPATED ACROSS BULK OF FA AND EXPECT MAINLY
CLEAR SKIES OVERNIGHT WITH HIGH PRESSURE PARKED ACROSS SOUTHEAST
CANADA WHICH WILL DRIFT THROUGH THE CANADIAN MARITIMES THIS
EVENING. EXPECT TEMPS WILL DROP QUICKLY AFTER SUNSET AND AS A
RESULT HAVE LOWS IN MOST AREAS SEVERAL DEGREES BELOW THOSE OF LAST
NIGHT. THERE SHOULD BE SOME VALLEY FOG OVERNIGHT AS TEMPS DROP TO
NEAR DEWPOINT AND HAVE THUS PLACED FOG IN THE FORECAST ACROSS MUCH
OF THE HUDSON VALLEY ESPECIALLY LATE TONIGHT. LOWS ARE EXPECTED TO
BE IN THE LOWER 20S TO LOWER 30S.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
FA WILL BE BRUSHED BY COASTAL LOW MAINLY LATE MONDAY INTO TUESDAY
WHICH WILL BE FOLLOWED BY HIGH PRESSURE TUESDAY NIGHT INTO
WEDNESDAY.
FOR MONDAY EXPECT THAT MID AND HIGH CLOUDS WILL START TO INCREASE
QUICKLY MONDAY MORNING FROM SOUTHEAST TO NORTHWEST WITH LOW LEVEL
CLOUDS QUICKLY OVERSPREADING SOUTHEAST PORTION OF FA BEFORE 18Z AS
GOOD MOISTURE CONVERGENCE H10-H8. FOR MONDAY AFTERNOON WILL BRING
CHANCE POPS MAINLY UP TO 190. HIGHS ON MONDAY WILL BE LIMITED BY
CLOUDS AND SLOW RECOVERY FROM OVERNIGHT LOWS. EXPECT HIGHS ON
MONDAY ONLY IN THE 40S ACROSS THE FA.
FOR MONDAY NIGHT INTO TUESDAY THE UNCERTAINTY EXISTS WITH HOW FAR
NORTH AND WEST PRECIPITATION SHIELD WILL EXTEND WITH SURFACE LOW
PASSING WELL EAST OF CAPE COD ON TUESDAY. FOR NOW WILL GO WITH
JUST CHANCE POPS MOST AREAS MONDAY NIGHT INTO TUESDAY...ALTHOUGH
WILL INCLUDE LIKELY POPS MONDAY NIGHT ACROSS FAR SOUTHEAST PORTION
OF FA. H10-H8 FRONTOGENESIS BARELY REACHES SOUTHEAST PORTION OF FA
MONDAY EVENING AND THEN AXIS SLIDES WELL EAST ACROSS FAR SOUTHEAST
NEW ENGLAND AND OFF CAPE COD. THIS EVENT LOOKS TO HAVE VERY
LITTLE QPF TO WORK WITH ACROSS FA AND ONLY HAVE QPF AMOUNTS MONDAY
NIGHT THROUGH TUESDAY FROM LESS THAN A TENTH OF AN INCH FAR NW
PORTION OF FA TO JUST OVER A THIRD OF AN INCH FAR SOUTHEAST
PORTION. ON MONDAY NIGHT WOULD EXPECT THAT ANY PCPN ACRS WRN
ADIRONDACKS WOULD BE IN THE FORM OF SNOW...BUT NOT SURE MOISTURE
WILL MAKE IT THAT FAR NORTH AND WEST. FOR NOW HAVE JUST PLACED A
FEW TENTHS OF AN INCH OF SNOW ACCUMULATION IN THE GRIDS.
EXPECT LOWS MONDAY NIGHT IN THE UPPER 20S TO LOWER 4S0 WITH HIGHS
ON TUESDAY IN THE UPPER 40S TO LOWER 50S.
FOR TUESDAY NIGHT HIGH PRESSURE EXPECTED TO BUILD ACROSS FA WITH
LOWS IN THE UPPER 20S TO MID 30S AND THIS WILL QUICKLY BE FOLLOWED
BY INCREASING CLOUDS ON WEDNESDAY AHEAD OF NEXT SYSTEM LIFTING
INTO THE UPPER GREAT LAKES LATE IN THE DAY. FOR NOW WILL ONLY
INCLUDE SLIGHT CHANCE POPS ACROSS FAR WESTERN ZONES WEDNESDAY
AFTERNOON. HIGHS ON WEDNESDAY EXPECTED TO BE IN THE UPPER 40S TO
LOWER 50S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
MUCH OF THE EXTENDED PERIOD WILL BE DOMINATED BY A DEVELOPING TROUGH
ACROSS THE EASTERN CONUS AND THE POSSIBILITY OF A PHASED STORM
SYSTEM AFFECTING THE NORTHEAST.
ON THANKSGIVING EVE INTO THANKSGIVING...A SLOW MOVING CUTOFF TROUGH
WILL BE MOVING ACROSS THE GREAT LAKES. AT THE SAME TIME...SFC LOW
PRESSURE WILL BE DEVELOPING IN THE SOUTHERN STREAM IN THE VICINITY
OF FLORIDA. AHEAD OF THE APPROACHING CUTOFF TROUGH...SOUTHERLY FLOW
WILL ALLOW FOR WEAK ISENTROPIC LIFT ACROSS OUR AREA...WHICH MAY
ALLOW FOR SOME SHOWERS. WITH 850 HPA TEMPS REMAINING ABOUT 1-5
DEGREES C...THIS SHOULD BE IN THE FORM OF RAIN SHOWERS. THE ACTIVITY
WILL BE RATHER SCT DUE TO THE WEAK FORCING...SO WILL KEEP POPS IN
THE CHC RANGE.
BY THURSDAY NIGHT...HOWEVER...THE FORECAST GETS A BIT MORE
INTERESTING...HOWEVER...STILL MUDDLED DUE TO SOME MODEL
INCONSISTENCIES. THE LARGE UPPER TROUGH OVER THE GREAT LAKES BEGINS
TO SHIFT EASTWARD TOWARDS THE UPPER OHIO VALLEY AND TAKES ON A MORE
NEGATIVE TILT AT 500 HPA. MEANWHILE...SFC PRESSURE BEGIN TO RAPIDLY
DEEPEN OFF THE COAST OF NJ...WITH SURPRISINGLY GOOD AGREEMENT
BETWEEN THE 12 UTC GFS/ECMWF AND MANY MEMBERS OF THE 12 UTC GEFS AS
WELL.
WITH THIS SFC/UPPER LEVEL SETUP...A STEADY PERIOD OF PRECIPITATION
IS LIKELY ACROSS THE REGION FOR SOMETIME THURSDAY NIGHT INTO FRIDAY.
WITH THE AIRMASS STARTING OUT NOT AWFULLY COLD AT ALL...PRECIP TYPE
WILL LARGELY BE ELEVATION DEPENDENT FOR THIS PORTION OF THE STORM.
SOME COLDER AIR WILL BE DRAWN INTO THE SYSTEM THROUGH THE DAY ON
FRIDAY...BUT AT THIS POINT...MUCH OF THE PRECIP IN THE VALLEYS LOOKS
TO BE A COLD RAIN...WITH A RAIN/SNOW MIX ACROSS THE HIGHER
ELEVATIONS...AS SFC TEMPS WILL REMAIN IN THE LOWER 30S ACROSS THE
HIGHER TERRAIN TO THE LOW 40S IN THE VALLEYS.
BY LATE FRIDAY...THE LOW PRESSURE WILL LIKELY BE SOMEWHERE NEAR THE
COAST OF MAINE OR EVEN SLIGHTLY INLAND ACROSS NORTHERN NEW ENGLAND.
HOWEVER...COLDER AIR WILL BE RUSHING IN ON THE WESTERN SIDE OF THE
SYSTEM...AND 850 HPA TEMPS WILL PLUNGE TO 0 TO -4 DEGREES C. THIS
MAY ALLOW FOR SOME LINGERING SNOW SHOWERS DUE TO THE UPPER TROUGH
OVERHEAD...EVEN ACROSS THE VALLEYS. SOME STEADY SNOW MAY CONTINUE
ACROSS THE DACKS DUE TO A DEFORMATION BAND...ALTHOUGH THIS WILL
ULTIMATELY DEPEND OF THE EXACT TRACK OF BOTH THE 500 HPA LOW AND SFC
SYSTEM. IN ADDITION...THE STRONG PRESSURE GRADIENT WILL ALLOW FOR
GUSTY NORTHWESTERLY WINDS...ESP ACROSS THE HIGHER TERRAIN AND
CHANNELED VALLEY LOCATIONS.
BY SATURDAY...LINGERING RAIN OR SNOW SHOWERS ARE POSSIBLE DUE TO THE
CYCLONIC FLOW AROUND THE LARGE UPPER TROUGH ACROSS THE NORTHEAST.
PRECIP TYPE WILL LARGELY BE ELEVATION AND DIURNAL
DEPENDENT...ALTHOUGH MAX TEMPS WILL BE LUCKY TO HIT THE 40 DEGREE
MARK...EVEN IN THE VALLEYS.
IT/S IMPORTANT TO NOTE THAT DESPITE SOME SIMILARITIES IN THE
MODELS...THERE IS STILL A GREAT DEAL OF UNCERTAINTY WITH THIS
SYSTEM. THE 12 UTC GGEM SHOWS NO PHASING...AS WELL AS A FEW GEFS
MEMBERS AS WELL. CONFIDENCE WILL BE INCREASED...HOWEVER...IF
SUBSEQUENT MODEL RUNS CONTINUE TO SHOW A SIMILAR SETUP TO TODAY/S
MODEL SUITE.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
CLOUDS SHOWING SIGNS OF ERODING FROM WEST TO EAST...WITH THE
CLEARING LINE TRENDING TOWARD THE HUDSON VALLEY EARLY THIS
AFTERNOON. THE MVFR CEILING SHOULD BREAK UP AND BECOME SCATTERED
BY 22-23Z AT KGFL AND KALB...BUT BECOME SCATTERED AT POU BY 19Z.
ONCE THE CLOUDS HAVE ERODED...THE EVENING THROUGH THE OVERNIGHT
PERIOD SHOULD BE MOSTLY CLEAR...WITH NO CEILING. SOME PATCHY FOG
COULD DEVELOP...BUT NOT WIDESPREAD ENOUGH TO INCLUDE BORDERLINE
IFR IN TAFS AT THIS TIME.
HOWEVER...NEXT TAF ISSUANCE WILL HAVE MORE DATA TO EVALUATE THE
FOG POTENTIAL...WHICH MAY NEED TO BE ENHANCED IN TAFS FOR
TONIGHT..STAY TUNED. WINDS WILL BE LIGHT NORTH TO NORTHEAST...AT
10 KT OR LESS THIS AFTERNOON AND TONIGHT. THE NEXT SYSTEM TO OUR
SOUTH AND SOUTHWEST APPROACHES TOWARD SUNRISE...AND CLOUDS WILL
REFORM AS BOUNDARY LAYER MOISTURE INCREASES. SO..BETWEEN
10-14Z...MVFR CEILING WILL DEVELOP AT POU...WHILE VFR CEILING WILL
SPREAD ACROSS KALB AND KGF TOMORROW MORNING. WINDS TOMORROW
MORNING WILL REMAIN NORTHEAST AT 10 KT OR LESS.
OUTLOOK...
MON-TUE...VFR-MVFR...CHC OF RAIN MON NT-TUE.
WED...VFR...CHC OF SHOWERS.
THU-FRI...MVFR/IFR...RAIN POSSIBLE LATE THU THROUGH FRI.
&&
.HYDROLOGY...
WITH DRY CONDITIONS EXPECTED TO LAST AT LEAST INTO MONDAY RIVERS
WILL CONTINUE RECEDE THROUGH MONDAY. THE NEXT THREAT OF
PRECIPITATION WILL BE LATE MONDAY INTO TUESDAY. EXPECT TOTAL QPF
AMOUNTS TO BE FAIRLY LIGHT WITH LESS THAN A TENTH OF AN INCH OF
QPF ACROSS NW ZONES TO A LITTLE OVER A THIRD OF AN INCH FAR
SOUTHEAST ZONES. THIS EVENT SHOULD HAVE VERY LITTLE IMPACT ON
RIVERS AND STREAMS. FURTHER OUT AN UNSETTLED PERIOD OF WEATHER
THURSDAY INTO THE WEEKEND COULD RESULT IN SIGNIFICANT
PRECIPITATION AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...11
NEAR TERM...11
SHORT TERM...11
LONG TERM...FRUGIS
AVIATION...NAS
HYDROLOGY...11
000
FXUS61 KBOX 221943
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
243 PM EST SUN NOV 22 2009
.SYNOPSIS...
HIGH PRESSURE ACROSS THE SAINT LAWRENCE VALLEY WILL MOVE EAST OF
NOVA SCOTIA MONDAY. A LOW PRESSURE WILL APPROACH OUR REGION MONDAY
INTO TUESDAY. WEAK HIGH PRESSURE WILL TEMPORARILY BUILD INTO THE
REGION TUESDAY NIGHT INTO WEDNESDAY NIGHT THEN MOVE OFFSHORE
THANKSGIVING DAY. ANOTHER LOW PRESSURE SYSTEM WILL MOVE UP THE COAST
LATE THURSDAY AND FRIDAY BRINGING A CHANCE OF MORE RAIN. COLDER
BLUSTERY WEATHER IS FORECAST FOR SATURDAY BEHIND THAT DEPARTING LOW.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE ACROSS THE SAINT LAWRENCE VALLEY THIS AFTERNOON WILL
MOVE TO NOVA SCOTIA OVERNIGHT. THIS WILL ALLOW NORTHEAST WINDS TO
BECOME MORE FROM THE EAST BY DAYBREAK. CURRENTLY WATCHING AN
EXPANSIVE AREA OF MARINE STRATUS ACROSS THE GULF OF MAINE AND GEORGES
BANK. LATEST VISIBLE IMAGERY SHOWING SOME OF THESE CLOUDS ARE DIURNAL
IN NATURE...AND SHOULD BRIEFLY DISSIPATE AROUND SUNSET.
HOWEVER...THE ONSHORE FLOW AND LOWERING TEMPERATURES WILL INCREASE
RELATIVE HUMIDITY AS THE EVENING WEARS ON. EXPECTING THESE LOWER
CLOUDS TO COME BACK LATE THIS EVENING AND LINGER THROUGH THE NIGHT.
SOME DRIZZLE IS POSSIBLE LATE TONIGHT...ESPECIALLY ALONG THE
IMMEDIATE COAST...BUT NOT OVERLY IMPRESSED WITH THE POTENTIAL.
A BLEND OF THE MAV/MET GUIDANCE LOOKS REASONABLE FOR TEMPERATURES.
&&
.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
STILL SOME UNCERTAINTY WITH THE TRACK AND INTENSITY OF A LOW PRESSURE
MOVING NORTHEAST FROM THE MID ATLANTIC COAST MONDAY NIGHT. FOR
NOW...USED A BLEND OF THE GFS AND NAM TO MINIMIZE FORECAST ERROR.
22/15Z SREF MEAN IS EVEN SLOWER AND WEAKER AND SLOWER THAN THAT
SOLUTION.
MOST 22/12Z MODELS BRING SOME RAINFALL TO SOUTHERN NEW ENGLAND DURING
THE DAY MONDAY...ESPECIALLY DURING THE AFTERNOON. GIVEN THE
UNCERTAINTY IN THE MODEL TIMING...DID TREND THE ARRIVAL OF THIS
PRECIPITATION FASTER THAN PREVIOUS FORECAST. THINKING THE BEST CHANCE
FOR THE ARRIVAL OF THIS RAIN WILL BE MONDAY NIGHT.
USED A BLEND OF THE MAV/MET GUIDANCE ONCE MORE FOR TEMPERATURES
DURING THIS PORTION OF THE FORECAST.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
TUESDAY...MODELS NOW ALL IN LINE WITH LOW PRESSURE MOVING FROM
SOUTH OF NANTUCKET MONDAY EVENING TO NEAR NOVA SCOTIA LATE TUESDAY
NIGHT. RAIN WILL MOVE ACROSS THE REGION FROM SOUTH TO NORTH MONDAY
EVENING. 00Z GFS WAS CONSIDERED OUTLIER WITH THE LOW TOO FAR OFF THE
COAST AND LITTLE RAINFALL OVER LAND. ECMWF TIMING AND PRECIP WAS THE
BASIS FOR THIS FORECAST. NEW 06Z GFS RUN NOW IS MORE IN LINE...EVEN
THOUGH ITS LOW IS STILL FARTHER EAST THAN THE OTHER MODELS...IT NOW
HAS RAIN AS FAR NORTH AS THE CT/RI/MA BORDER BY MON EVENING. HAVE
INCREASED POPS TO 60 PERCENT NORTHWEST AND 90 PERCENT SOUTHEAST.
IN GENERAL...0.5 INCHES OF RAIN IS EXPECTED IN MANY AREAS. HOWEVER...
THE COMBINATION OF STRONG MOIST ESE FLOW AT 925 MB OVERRUNNING
LESSER NE FLOW AT THE SURFACE WILL LEAD TO THE POTENTIAL FOR LOCALLY
HEAVY SHOWERS BETWEEN MIDNIGHT AND NOON TUESDAY. BEST CHANCE IS
ALONG EASTERN MA COAST. GFS SHOWS MORE THAN 2 INCHES OF RAIN OVER
THE OPEN WATERS...THIS WILL NEED TO BE WATCHED IN CASE HEAVY RAIN
OCCURS OVER THE COASTAL AREAS.
DESPITE PERSISTENT ONSHORE FLOW MONDAY/TUESDAY...ASTRONOMICAL TIDES
ARE LOW AND THE SYSTEM DOES NOT APPEAR INTENSE ENOUGH TO RESULT IN
ANY COASTAL FLOODING. HOWEVER...MINOR BEACH EROSION CERTAINLY IS
POSSIBLE.
STUCK WITH PREVIOUS FORECAST HIGH TEMPERATURES SINCE THEY WERE
SIGNIFICANTLY COOLER THAN GFS GUIDANCE. CONFIDENCE IS HIGH THAT IT
WILL BE COOL AND RAW DURING THE AFTERNOON WITH THE ONSHORE FLOW.
TUESDAY NIGHT AND WEDNESDAY...
LOW PULLS OUT TO THE EAST AND WEAK HIGH PRESSURE MOVES IN.
THE PROBLEM IS THAT THERE WILL STILL BE ABUNDANT LOW LEVEL MOISTURE.
925 MB RELATIVE HUMIDITY REACHES 90-100 PERCENT WED AFTERNOON.
HAVE GONE WITH CLOUDY FORECAST. REDUCED CHANCE OF SHOWERS TO 20 TO 30
PERCENT IN NW HALF OF AREA BECAUSE GFS SHOWED A WEAK VORTICITY MAX
MOVING THROUGH IN THE FAST SW FLOW ALOFT. SHOULD BE LIGHT IF ANYTHING
DUE TO DRYING AIR ALOFT. HIGHS SHOULD MAINLY BE FROM 50 TO 55.
WEDNESDAY NIGHT THROUGH THANKSGIVING...
MORE OF THE SAME...GENERALLY MOSTLY CLOUDY SKIES DUE TO LOW LEVEL
MOISTURE AS FLOW REMAINS EASTERLY BEHIND DEPARTING WEAK HIGH PRESSURE
AND AHEAD OF DEVELOPING LOW PRESSURE OFF THE CAROLINA COAST. HAVE LOW
PROBABILITIES OF SHOWERS...BUT IT MAY TURN OUT TO BE MORE OF A
CHANCE OF DRIZZLE ACROSS THE AREA. LOWS MID 30S TO LOWER 40S AND
HIGHS IN THE 50S.
THURSDAY NIGHT THROUGH FRIDAY NIGHT...
A VIGOROUS UPPER LEVEL TROUGH DEVELOPING FROM THE GREAT LAKES TO THE
OHIO VALLEY WILL INTENSIFY THE CAROLINA LOW PRESSURE SYSTEM AS IT
MOVES NORTHWARD UP THE EAST COAST. 00Z GFS DEEPENS IT TO 973 MB OVER
NEW ENGLAND COMPLETE WITH LOTS OF THUNDER ETC. 06Z GFS CONTINUES THIS
FORECAST WITH 974 MB. THESE WERE CONSIDERED TOO DEEP AS ECMWF REMAINS
CONSISTENT WITH 998 MB WHICH IS WEAKER THAN ITS PREVIOUS RUN OF 993
MB. THE PLACEMENT OF THIS STORM WILL DETERMINE WHERE THE HEAVIEST
RAIN WOULD FALL. RIGHT NOW...WE HAVE ADDED 50 TO 60 PERCENT POPS TO
THE FORECAST FROM LATE THU NIGHT THROUGH FRIDAY...DIMINISHING
SOMEWHAT FRI NIGHT. IT SHOULD BE NOTED THAT THE CANADIAN GGEM MODEL
IS DRY THROUGHOUT FRIDAY. THUS AT THIS TIME...CONFIDENCE IS ONLY MEDIUM
THAT A STORM WILL FORM...AND EVEN LOWER AS TO ITS PLACEMENT.
SATURDAY...BLUSTERY AND CHILLY WEATHER LOOKS TO BE FILTERED INTO
THE REGION BEHIND THE SYSTEM. WITH THE UPPER LOW PRESSURE DIRECTLY
OVERHEAD...EXPECT RATHER UNSTABLE CONDITIONS WHICH COULD LEAD TO A
FEW RAIN SHOWERS IN THE SOUTH AND EAST AND SNOW SHOWERS IN THE
NORTHWEST...ESPECIALLY IN THE HIGHER TERRAIN. IT WILL BE TOO WARM AT THE
SURFACE FOR ANY ACCUMULATION. HIGHS ARE FORECAST TO BE IN THE UPPER
30S NORTHWEST TO MID 40 SOUTHEAST.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
THIS AFTERNOON...VFR WEST OF KMHT-KORH-KIJD. AREAS MVFR CIGS EAST OF
THAT LINE...ESPECIALLY EAST OF KLWM-KPVD-KMVY...DUE TO MARINE STRATUS
MOVING ONSHORE.
TONIGHT...BRIEF VFR POSSIBLE SHORTLY AFTER SUNSET ACROSS EASTERN MA
AND RI. MVFR CIGS MOVING IN FROM SOUTHEAST TO NORTHWEST OVERNIGHT.
MONDAY...EXPECT VFR CIGS MAINLY N OF ROUTE 2 ACROSS N MA...WHILE
CONDITIONS LOWER TO MVFR-IFR CIGS S OF THERE. LOCAL IFR CIGS ALONG
THE S COAST...CAPE COD AND THE ISLANDS DURING THE AFTERNOON. PATCHY
RAIN WILL APPROACH N CT/RI/SE MA DURING THE AFTERNOON WITH LOCAL
MVFR VSBYS.
MONDAY NIGHT...MVFR. AREAS OF IFR CONDITIONS IN LOW CLOUDS...RAIN
AND FOG...MAINLY EASTERN SECTIONS.
OUTLOOK /TUESDAY THROUGH FRIDAY/...
TUESDAY...IFR CONDITIONS IN LOW CLOUDS...RAIN AND FOG. LOCALLY
HEAVIER SHOWERS MAINLY EASTERN SECTIONS.
TUE NIGHT THROUGH THU...MVFR-IFR CONDITIONS MAY LINGER IN LOW
CLOUDS THROUGH THIS PERIOD. ONLY SLIGHT CHANCE OF A RAIN SHOWER BUT
MAY HAVE AREAS OF DRIZZLE AND FOG DEVELOPING...ESPECIALLY WED NIGHT.
THU NIGHT AND FRI...LOW TO MEDIUM CONFIDENCE OF IFR CEILINGS AND
VSBYS IN SHOWERS.
&&
.MARINE...
NORTHEAST WINDS SHOULD SHIFT EAST OVERNIGHT. THE PERSISTENT ONSHORE
FLOW WILL CONTINUE TO BUILD SEAS OVERNIGHT ACROSS THE COASTAL WATERS
OF MA AND RI. A LOW PRESSURE MOVING NORTHEAST FROM THE MID ATLANTIC
COAST MONDAY AND MONDAY NIGHT WILL LIKELY INCREASE WINDS DURING THIS
TIME AS WELL. SMALL CRAFT ADVISORIES CONTINUE FOR MOST WATERS.
OUTLOOK /TUESDAY THROUGH THURSDAY/...
TUESDAY THROUGH EARLY WEDNESDAY...LOW PRESSURE PASSING FROM SOUTH OF
NANTUCKET TO NOVA SCOTIA WILL CREATE A PERSISTENT NORTHEAST FLOW AND
GOOD GRADIENT. THIS WILL RESULT IN SCA ACROSS MOST OF OUR WATERS OVER
THIS TIME PERIOD. SEAS MAY BUILD TO BETWEEN 7 AND 12 FEET ACROSS THE
OUTER WATERS. THERE IS A LOW PROBABILITY OF BRIEF MARGINAL GALE FORCE
GUSTS MAINLY VERY LATE MON NIGHT OR ON TUESDAY OVER THE SOUTHERN
WATERS.
WEDNESDAY THROUGH THANKSGIVING...WINDS WILL CONTINUE FROM A
PERSISTENT EASTERLY DIRECTION PERHAPS BECOMING SOUTHEAST LATER THU.
THIS WILL LIKELY CAUSE SEAS TO REMAIN ABOVE SCA THRESHOLDS ACROSS THE
OUTER-WATERS. WINDS AND SEAS MAY ONCE AGAIN INCREASE VERY LATE
THANKSGIVING NIGHT IN ADVANCE OF THE NEXT SYSTEM APPROACHING FROM THE
SOUTH.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 5 AM TO 5 PM EST MONDAY FOR
ANZ232>235-237.
SMALL CRAFT ADVISORY UNTIL 5 PM EST MONDAY FOR ANZ250-254>256.
&&
$$
SYNOPSIS...BELK/GAF
NEAR TERM...BELK/GAF
SHORT TERM...BELK
LONG TERM...GAF
AVIATION...BELK/GAF
MARINE...BELK/GAF
000
FXUS61 KOKX 221818
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
118 PM EST SUN NOV 22 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER THE NORTHEASTERN UNITED STATES AND
THE CANADIAN MARITIME PROVINCES THROUGH MONDAY...THE SLIDE EAST
INTO MIDWEEK. MEANWHILE AN AREA OF LOW PRESSURE WILL MOVE FROM THE
GULF COAST TO THE SOUTHEAST COAST TODAY AND MONDAY. THE LOW TRACKS
ALONG THE SEABOARD THROUGH TUESDAY...REACHING THE CANADIAN
MARITIMES WEDNESDAY. WEAK HIGH PRESSURE BUILDS DOWN FROM THE
NORTH WEDNESDAY...BEFORE RETREATING TO THE EAST WEDNESDAY NIGHT AS
A COMPLEX STORM SYSTEM APPROACHES FROM THE WEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
PROBLEM OF THE DAY CENTERS AROUND STRATOCU MAINLY OVER ORANGE
COUNTY...WHICH FILLED IN VIA DAYTIME HEATING/MIXING THIS MORNING.
EASTERN EDGE IS SHOWING SIGNS OF EROSION AS MIXING DEEPENS...AND
FORECAST SOUNDINGS FOR STEWART AIRPORT INDICATE THIS SHOULD
CONTINUE THIS AFTERNOON...SO WILL TREND BACK TOWARD PARTLY/MOSTLY
SUNNY. STRATOCU JUST SE OF THE FORKS OF LONG ISLAND MAY REACH THE
SOUTH SHORE...BUT MAKE LITTLE INLAND PROGRESS AS HEATING OVER LAND
PREVENTS MUCH OF AN INLAND PUSH. OKX MORNING SOUNDING AND FORECAST
GUIDANCE TEMPS ARE ALL ON THE SAME PAGE...WITH MAINLY MID 50S...
PERHAPS SOME UPPER 50S IN URBAN NORTHEAST NJ AND PARTS OF THE CT
RIVER VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
UPPER RIDGE MOVES EAST TONIGHT WITH SURFACE HIGH OVER THE CANADIAN
MARITIMES. SURFACE LOW SHIFTS TO THE SOUTHEAST COAST. CLOUDS BEGIN
TO MOVE IN FROM THE SOUTH AS THE LOW DEEPENS AND TRACKS NORTH.
WITH THAT...AND NORTHEASTERLY FLOW...TEMPERATURES ALONG THE COAST
NOT EXPECTED TO FALL OFF TOO MUCH...AND INLAND TEMPERATURES TO
FALL OFF UNDER MOSTLY CLEAR SKIES...SO WILL BE LARGE CONTRAST.
MONDAY PRECIPITATION FROM THE COASTAL LOW MOVES IN FROM SOUTH TO
NORTH. GOOD AGREEMENT WITH BRINGING LIGHT RAIN INTO THE AREA
MONDAY MORNING INTO THE AFTERNOON. BEST CHANCES WILL BE MONDAY
NIGHT INTO TUESDAY AS BEST ISENTROPIC LIFT MOVES INTO THE AREA.
HAVE RAISED POPS TO LIKELY. TUESDAY BEST LIFT STARTS TO SHIFT EAST
AND LOWER POPS TUESDAY INTO TUESDAY NIGHT. GFS A LITTLE FASTER AND
DEEPER WITH THE SURFACE LOW TUESDAY INTO TUESDAY NIGHT AND LEANED
TOWARD THE SREF AND NAM. HEAVIEST PRECIPITATION LIKELY ACROSS
SOUTHEASTERN CONNECTICUT AND INTO LONG ISLAND WITH AREA OF BEST LIFT.
WITH CLOUD COVER...PRECIPITATION...AND EASTERLY WINDS WILL NOT SEE
A LARGE RANGE IN LOWS AND HIGHS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
RIDGING BUILDS BRIEFLY BETWEEN SYSTEMS WEDNESDAY...WITH LOW
DEPARTING TO THE EAST AND NEXT SYSTEM APPROACHING FROM THE WEST.
HAVE DECIDED TO KEEP SLIGHT CHANCE POPS TUESDAY NIGHT WITH SOME
UNCERTAINTY AS TO TIMING OF LOWS.
SOUTHWEST FLOW ALOFT DEVELOPS WEDNESDAY AS H5 LOW DROPS INTO THE OHIO
VALLEY. H3 JET PRODUCES SOME LIFT...BUT FORCING OTHERWISE IS WEAK
AS EVIDENCED BY THE TIME HEIGHTS. WITH MARGINAL MOISTURE...ONLY
LIGHT PRECIPITATION EXPECTED AT THIS TIME. FOCUS SHIFTS TO LATE
THURSDAY AND FRIDAY. ANOTHER H5 LOW DROPS INTO THE OHIO VALLEY
WITH A COMPLEX REFLECTION AT THE SURFACE. MODELS HINT AT LOW
PRESSURE DEVELOPING ALONG THE NORTHERN GULF COAST AND TRACKING
NORTHEASTWARD OFF THE ATLANTIC COAST...WITH A SECOND LOW
DEVELOPING OVER THE EASTERN GREAT LAKES. ALL THOUGH THERE IS A
SPREAD IN THE MODEL SOLUTIONS...IT APPEARS A SHOT OF RA ON TRACK
DURING THE PERIOD. MAIN ISSUE MAY TURN OUT TO BE THE WIND IF THE
12Z GFS/ECMWF SOLUTIONS ARE CLOSE AND A 980 MB LOW OCCLUDES OVER
NORTHERN NEW ENGLAND SATURDAY MORNING.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
VFR THROUGH THIS AFTERNOON...ALTHOUGH CEILINGS MAY DEVELOP EARLY
THIS EVENING. THICK ST/SC DECK OVER EASTERN LONG ISLAND IS INCHING
WESTWARD. TENDRELS OF ST ALSO DEVELOPING OVER LONG ISLAND SOUND.
MVFR CIGS ARE POSSIBLE AFTER ABOUT 21Z...BUT WILL NEED TO MONITOR
SAT TRENDS TO NAIL DOWN TIMING AND INCLUDE IN TAFS.
ONCE CIGS DEVELOP...THEY SHOULD REMAIN IN PLACE OVERNIGHT.
WIND DIRECTIONS MAY VARY FROM 350 TO 060 THIS AFTERNOON...BUT THE
GENERAL TREND WILL BE SHIFTING TOWARD THE EAST.
OUTLOOK 18Z MONDAY THROUGH THURSDAY...
MONDAY THRU TUESDAY PM...SUB-VFR...PDS OF IFR LIKELY. GUSTY E-NE
WINDS.
TUESDAY NIGHT...BECOMING VFR.
WEDNESDAY...VFR.
WEDNESDAY NIGHT-THURSDAY ...SUB-VFR POSSIBLE.
&&
.MARINE...
AT 15Z...BUOY 44025 HAD 4-FT SEAS WITH A STEADY 2.3-FT SWELL...AND
NE WINDS AROUND 17 KT. WIND SPEEDS/FETCH SHOULD INCREASE A LITTLE
THIS AFTERNOON AS HIGH PRESSURE BUILDS TO THE NORTH...SO THINK
5-FT SEAS ARE POSSIBLE BY MID TO LATE AFTERNOON FROM THERE
EAST...SO HAVE RAISED SCA A LITTLE SOONER E OF FIRE ISLAND INLET.
EXPECT SCA CONDITIONS WITH GUSTS TO 25-30 KT ON ALL WATERS TONIGHT
INTO MONDAY IN RESPONSE TO CONTINUED TIGHTENING PRESSURE GRADIENT
BETWEEN HIGH WEDGED INTO THE NORTHEASTERN US AND LOW PRESSURE
APPROACHING FROM THE S. SEAS ON THE OCEAN ZONES WILL BUILD TO 4 TO
8 FT BY MONDAY AS A RESULT OF STRENGTHENING NE FLOW.
DEPENDING ON EXACT TRACK/STRENGTH OF THE COASTAL LOW...THERE IS
THE POTENTIAL FOR GUSTS TO GALE FORCE ON THE OCEAN E OF FIRE
ISLAND INLET...AND POSSIBLY A LARGER AREA. FORECAST CONFIDENCE IS
NOT HIGH ENOUGH TO GO A WITH GALE WATCH...BUT WILL MENTION
OCCASIONAL GUSTS TO 35 KT AND EXTEND SCA ON COASTAL OCEAN WATERS
THROUGH MON NIGHT. STILL ENOUGH UNCERTAINTY ON LOW TRACK/STRENGTH
THAT NOT AS CONFIDENT OF SCA CONDITIONS OVER THE SOUND/HARBOR/BAYS
MONDAY NIGHT.
WINDS SHOULD SLOWLY DIMINISH TUE NIGHT AS LOW PULLS AWAY TO THE NE.
WHILE WINDS SHOULD FALL BELOW SCA LEVELS ON ALL WATERS TUE
NIGHT...OCEAN SEAS WILL LIKELY WILL REMAIN AT OR ABOVE SCA LEVELS
INTO THU.
WINDS SHOULD STAY BELOW SCA LEVELS WED INTO THU...WITH REGION IN
BETWEEN POTENTIALLY STRONG COASTAL STORMS.
&&
.HYDROLOGY...
DRY THROUGH MONDAY MORNING. QPF OF 1/2 NORTH/WEST TO 1 INCH
SOUTH/EAST IS POSSIBLE FROM MON AFTERNOON THROUGH WED.
ADDITIONAL PRECIPITATION IS POSSIBLE THU AND FRI. NO HYDROLOGIC
PROBLEMS ARE ANTICIPATED.
&&
.TIDES/COASTAL FLOODING...
DEPARTURES OF 2.0-2.5 FT AND 2.5-3.0 FT ARE NEEDED FOR THE
HIGHER/LOWER HIGH TIDE CYCLES ON MON/TUE TO PRODUCE MINOR COASTAL
FLOODING. CURRENT GUIDANCE FORECASTS DEPARTURES OF 0.5-1.0 FT...
BUT IS BASED ON A TRACK THAT BOTH FASTER AND FARTHER OUT TO SEA
THAN CURRENT THINKING. EVEN SO...A SLOWER/CLOSER LOW TRACK MAY
STILL NOT PRODUCE DEPARTURES LARGE ENOUGH TO CAUSE COASTAL
FLOODING. THIS WILL CONTINUE TO BE MONITORED CLOSELY.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 5 PM EST MONDAY
FOR ANZ330-335-338-340-345.
SMALL CRAFT ADVISORY UNTIL 6 AM EST TUESDAY FOR ANZ350-353.
SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EST
TUESDAY FOR ANZ355.
&&
$$
SYNOPSIS...MET
NEAR TERM...BG
SHORT TERM...MET
LONG TERM...
AVIATION...BS
MARINE...BG/PFM
HYDROLOGY...MET
TIDES/COASTAL FLOODING...
000
FXUS61 KALY 221737
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
1237 PM EST SUN NOV 22 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL COVER THE NORTHEAST TO START THE
WEEK. IT WILL SLIDE EAST INTO THE MARITIMES AND OFFSHORE LATE MONDAY.
OUR WEATHER WILL TURN UNSETTLED MUCH OF THE UPCOMING WEEK. THE FIRST
LOW PRESSURE AREA WILL MOVE NORTHEAST FROM THE CAROLINA COAST
OFFSHORE MONDAY NIGHT AND TUESDAY. THEN MIDWEEK A SERIES OF MUCH
STRONGER STORMS WILL MOVE THOUGH THE MIDWEST AND GREAT LAKES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MOISTURE IS CONTINUING TO BE TRAPPED UNDER AN INVERSION...AND
CLOUD COVER EXTENDS FROM THE NY AND NEW ENGLAND BORDER WESTWARD
ACROSS NY AND NORTHERN PA. BASED ON UPSTREAM CONDITIONS...AND
LIGHT WIND FLOW THROUGH THE BOUNDARY LAYER...CLOUD COVER SHOULD
PERSIST MUCH OF THE DAY. SOME SLIGHT EROSION SEEN IN WESTERN NEW
ENGLAND PERHAPS SLOWLY BUILDING WEST DURING THE DAY...BUT MIX OF
CLOUDS AND SUN LIKELY FROM PSF TO AQW AND DDH...RIGHT ALONG THE
EDGE OF THE CLOUDS. SOME DEEPER SUBSIDENCE SHOULD BUILD INTO THE
REGION TOWARD AND THROUGH THE EVENING...SO ACKNOWLEDGING SOME
BETTER EROSION TO THE CLOUDS FROM EAST TO WEST LATE THIS AFTERNOON
AND EVENING. SO...SOME BREAKS IN THE CLOUDS ARE POSSIBLE FROM THE
HUDSON VALLEY LATE THIS AFTERNOON OR AROUND SUNSET. NUDGED HIGH
TEMPERATURES DOWN A DEGREE OR TWO BASED ON THE CLOUD COVER...WHICH
WAS EXPANDED. THE REST OF THE FORECAST REMAINS UNTOUCHED.
PREV AFD BELOW...
MOISTURE TRAPPED BENEATH LOW LEVEL SUBSIDENCE INVERSION WILL KEEP
PATCHY LOW CLOUDS AROUND THROUGH AT LEAST LATE THIS MORNING. IN
FACT...WHERE SOME BREAKS HAVE DEVELOPED...CLOUDS MAY ACTUALLY
REDEVELOP AROUND OR JUST AFTER SUNRISE ONCE SHALLOW MIXING
DEVELOPS. EVENTUALLY...AS THE LOW LEVEL FLOW VEERS INTO A MORE NE
DIRECTION...SOME DOWNSLOPING OFF THE HIGHER TERRAIN TO OUR N/E
SHOULD ALLOW FOR MORE BREAKS IN THE CLOUDS TO DEVELOP THIS
AFTERNOON...ESP FROM THE HUDSON RIVER VALLEY EASTWARD. CLOUDS MAY
PERSIST LONGER...PERHAPS WELL INTO THE AFTERNOON...ACROSS WESTERN
PORTIONS OF THE REGION...FROM THE SW DACKS...WESTERN MOHAWK VALLEY
INTO THE SCHOHARIE VALLEY AND NE CATSKILLS.
AS FOR MAX TEMPS...GIVEN THE EXPECTATION FOR SHALLOW MIXING...MAINLY
TO 925-950 MB...WE EXPECT MAXES TO BE A BIT COOLER THAN SAT...ESP
GIVEN A SLIGHTLY COLDER START...ALONG WITH THE EXPECTATION FOR
CLOUDS THROUGH THE MORNING. SO...GENERALLY SIDED CLOSE TO THE COOLER
MET MOS...WITH MAXES GENERALLY REACHING AROUND 50 WITHIN MUCH OF THE
HUDSON RIVER VALLEY...EXCEPT LOWER/MID 50S ACROSS THE MID HUDSON
VALLEY...WITH MAINLY 40S ACROSS HIGHER ELEVATIONS WITHIN WESTERN NEW
ENGLAND AND WESTERN PORTIONS OF THE REGION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
PERIOD STARTS WITH RIDGING AND SUBSIDENCE THROUGHOUT THE
ATMOSPHERE WITH 572DM HIGH EVEN AT 500HPA. 500HPA TROF LINGERS
SOUTH OF RGN FM MASON DIXON LINE TO LONG IS NY WHILE IMPRESSIVE
SFC HIGH DOMINATES THE NORTHEAST QUARTER OF THE NATION AND IS
CENTERED OVER THE MARITIMES. WHILE THE DIRTY HIGH PHASE WITH
MOISTURE TRAPPED UNDER THE INVERSION WILL HAVE ENDED EARLY SUNDAY
THE NEW GUIDANCE SUGGESTS THE MOIST BOUNDARY LAYER REMAINS AND
SHOWS MARINE LAYER MOISTURE OR FOG/STRATUS CREEPING BACK UP THE
HUDSON VALLEY EVEN AS EARLY AS LATE SUNDAY NIGHT EARLY MONDAY
MORNING. THE WITH ALL THE MODELS AND STATISTICAL GUID KEEPING THE
FLOW EAST TO NORTHEAST BELOW THE INVERSION LAYER...WILL BRING
CLOUDS INTO THE SOUTHEAST. THE NAM IS THE ONLY LESS AGGRESSIVE
MODEL WITH ADVECTING THIS MARINE LAYER MOISTURE WHILE THE
WRF/GEM/GFS SHOW IT BLO 900HPA.
MUCH LIKE LAST WEEK WHEN THIS SAME SCENARIO OCCURRED CLOUDS SHOULD
BARELY MAKE ALBANY MONDAY MORNING AND THESE MAY ERODE FOR A TIME.
FROM ALB N & W WILL STAY FAIR A GOOD PART OF THE DAY TILL BOUNDARY
LEVEL FLOW TURNS SE-S AND MOISTURE STREAMS NORTH. IN SOUTHEAST
LOOKING AT AREAS OF MORNING STRATUS AND FOG THAT MAY OR MAY NOT
BURN OFF BEFORE THE CLOUDS FROM NEXT SYSTEM OVERSPREAD THOSE
AREAS.
MARINE LAYER MOISTURE ADVECTION SHOULD BE WEAK TILL 500HPA TROF
THAT WAS LAYING DORMANT ACROSS THE MID ATLC BEGINS MOVES NORTH
INTO OUR REGION MONDAY. MODELS SUGGEST A COASTAL DEVELOPMENT BUT
ITS WELL OFFSHORE AND ITS MAIN IMPACT IS TO ENHANCE THE MARINE
LAYER INFLOW. THIS MOISTURE AND THE PASSAGE OF SEVERAL 500HPA
SHORT WAVES WILL PRODUCE CLOUDS ACROSS THE AREA AND AN INCR CHC
OF -RN AND DZ MONDAY NIGHT AND TUES MAINLY IN THE SOUTHEAST.
INITIALLY TUESDAY NIGHT THE SFC LOW DEPARTS WELL OFFSHORE. 500HPA
RIDGE REBUILDS ALONG THE SEABOARD. WELL TO OUR WEST THE STAGE IS
BEING SET FOR A COMPLEX PATTERN TO END THE WEEK. TUES NT WERE
STUCK WITH MORE RESIDUAL LOW LEVEL MOISTURE AND NOT MUCH MORE THAN
DRIZZLE AND CLOUDS.
MEANWHILE TUESDAY NIGHT TWO CUTOFFS WILL BE SETTING UP. ONE IN
THE MISSISSIPPI VALLEY THE OTHER IN SOUTH CENTRAL CANADA. LOOKING
AT THE 1.5PVU SFCS THE ORIGINS OF THESE SYSTEMS ARE THREE
PART. 1) JUST OFF THE BRITISH COLUMBIA ALASKA PANHANDLE
COAST...2) IN THE FAST FLOW IN THE CENTRAL PACIFIC NORTH OF
HAWAII AND 3) ALONG ALASKA`S BROOKS RANGE. OBVIOUSLY MANY
QUESTIONS REMAIN ABOUT THE PHASING PROCESS AND THE RESULTANT SFC
WEATHER. MORE IN THIS IN LONG TERM SECTION.
THROUGH TUESDAY NIGHT THERES A FAIR AMOUNT OF MODEL CONSISTENCY
EXCEPT WITH REGARD TO THE MAGNITUDE OF THE MARINE LAYER INFLOW
MONDAY AS DISCUSSED ABOVE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE LONG RANGE FORECAST PERIOD IS THE RESULT OF THE ORGANIZATION OF
TWO MAJOR CUT OFFS AND THEIR INTERACTION AND EVENTUAL MERGER. GIVEN
THE LOCATIONS OF THE VORTICITY THAT WILL GIVE RISE TO THIS SCENARIO
(GIVEN AT END OF SHORT TERM)...MUCH REMAINS UNCERTAIN AND SUBJECT
TO CHANGE BASED ON THE PHASING TIME...DEGREE...LOCATION AND THEN THE
ULTIMATE SFC RESPONSE.
THERE ARE SOME GENERAL THEMES IN MOST OF THE GUIDANCE. ONE CUT
OFF OVER THE MID WEST LIFTS NORTHEAST INTO THE RIDGE OVER THE
EASTERN SEABOARD WEDNESDAY. THE SECOND DIVES SOUTH OUT OF CENTRAL
CANADA. THEY DUMBBELL AROUND EACH OTHER AND MERGE BY THEN END OF
THE WEEK. HWVR POSITIONS RANGE FM CENTERED N OF YUL (GEM)..TO NJ
(GFS) TO OHIO (ECMWF).
WHAT IS MOST CONCRETE AT THIS POINT IS WEDNESDAY THE FIRST 500HPA
CUT OFF MOVES FM MIDWEST INTO GRT LAKES AND PUSHES AN OCCLUDED
FRONT INTO NYS LATE IN THE DAY. THE GFS/GEM AND ECMWF SHOW THIS
SCENARIO WITH THAT CANADIAN ABOUT 6 HOURS FASTER WITH PCPN. WILL
KEEP IT DRY IN THE MORNING WITH CHC POPS AFTN AND WED NIGHT.
THE TIMING ISSUES BECOME MORE ACUTE FROM THURSDAY ON. THURSDAY
THE GFS PUTS FCA IN DRY SLOT AHEAD OF NEXT FRONTAL SYSTEM PUSHING
ACROSS FCA. THE GEM/ECM BRING THE NEXT FRONTAL SYSTEM THROUGH.
IN SUMMARY THE LONG RANGE PERIOD GENERAL THEMES ARE FAIRLY
CLEAR...BUT TIMING IS ALL OVER. OTHER THAN WED WILL LEAVE MUCH OF
THE EARLIER HPC BASED LONG RANGE IN PLACE WITH JUST SOME TWEAKS TO
IMPROVE COORDINATION. TO CHANGE IT TO GMOS AT THIS TIME WILL JUST
INCREASE THE FLIP FLOP FACTOR.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
CLOUDS SHOWING SIGNS OF ERODING FROM WEST TO EAST...WITH THE
CLEARING LINE TRENDING TOWARD THE HUDSON VALLEY EARLY THIS
AFTERNOON. THE MVFR CEILING SHOULD BREAK UP AND BECOME SCATTERED
BY 22-23Z AT KGFL AND KALB...BUT BECOME SCATTERED AT POU BY 19Z.
ONCE THE CLOUDS HAVE ERODED...THE EVENING THROUGH THE OVERNIGHT
PERIOD SHOULD BE MOSTLY CLEAR...WITH NO CEILING. SOME PATCHY FOG
COULD DEVELOP...BUT NOT WIDESPREAD ENOUGH TO INCLUDE BORDERLINE
OFR IN TAFS AT THIS TIME.
HOWEVER...NEXT TAF ISSUANCE WILL HAVE MORE DATA TO EVALUATE THE
FOG POTENTIAL...WHICH MAY NEED TO BE ENHANCED IN TAFS FOR
TONIGHT..STAY TUNED. WINDS WILL BE LIGHT NORTH TO NORTHEAST...AT
10 KT OR LESS THIS AFTERNOON AND TONIGHT. THE NEXT SYSTEM TO OUR
SOUTH AND SOUTHWEST APPROACHES TOWARD SUNRISE...AND CLOUDS WILL
REFORM AS BOUNDARY LAYER MOISTURE INCREASES. SO..BETWEEN
10-14Z...MVFR CEILING WILL DEVELOP AT POU...WHILE VFR CEILING WILL
SPREAD ACROSS KALB AND KGF TOMORROW MORNING. WINDS TOMORROW
MORNING WILL REMAIN NORTHEAST AT 10 KT OR LESS.
OUTLOOK...
MON-TUE...VFR-MVFR...CHC OF RAIN MON NT-TUE.
WED...VFR...CHC OF SHOWERS.
THU-FRI...MVFR/IFR...RAIN POSSIBLE LATE THU THROUGH FRI.
&&
.HYDROLOGY...
WITH DRY CONDITIONS EXPECTED TO LAST AT LEAST INTO MONDAY RIVERS
WILL CONTINUE RECEDE THROUGH MONDAY. THE NEXT THREAT OF RAIN WILL
BE LATE MONDAY INTO TUESDAY. CONSENSUS OF MODELS IS FOR 0.10 TO
0.30 INCHES MAINLY IN THE SOUTHEAST. THIS EVENT SHOULD HAVE MODEST
IMPACT ON RIVERS AND STREAMS. FURTHER OUT AN UNSETTLED PERIOD OF
WEATHER THURSDAY INTO THE WEEKEND COULD RESULT IN SIGNIFICANT
PRECIPITATION AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
AVIATION...NAS
000
FXUS61 KOKX 221613
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1113 AM EST SUN NOV 22 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER THE NORTHEASTERN UNITED STATES AND
THE CANADIAN MARITIME PROVINCES THROUGH MONDAY...THE SLIDE EAST
INTO MIDWEEK. MEANWHILE AN AREA OF LOW PRESSURE WILL MOVE FROM THE
GULF COAST TO THE SOUTHEAST COAST TODAY AND MONDAY. THE LOW TRACKS
ALONG THE SEABOARD THROUGH TUESDAY...REACHING THE CANADIAN
MARITIMES WEDNESDAY. WEAK HIGH PRESSURE BUILDS DOWN FROM THE
NORTH WEDNESDAY...BEFORE RETREATING TO THE EAST WEDNESDAY NIGHT AS
A COMPLEX STORM SYSTEM APPROACHES FROM THE WEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
PROBLEM OF THE DAY CENTERS AROUND STRATOCU MAINLY OVER ORANGE
COUNTY...WHICH FILLED IN VIA DAYTIME HEATING/MIXING THIS MORNING.
EASTERN EDGE IS SHOWING SIGNS OF EROSION AS MIXING DEEPENS...AND
FORECAST SOUNDINGS FOR STEWART AIRPORT INDICATE THIS SHOULD
CONTINUE THIS AFTERNOON...SO WILL TREND BACK TOWARD PARTLY/MOSTLY
SUNNY. STRATOCU JUST SE OF THE FORKS OF LONG ISLAND MAY REACH THE
SOUTH SHORE...BUT MAKE LITTLE INLAND PROGRESS AS HEATING OVER LAND
PREVENTS MUCH OF AN INLAND PUSH. OKX MORNING SOUNDING AND FORECAST
GUIDANCE TEMPS ARE ALL ON THE SAME PAGE...WITH MAINLY MID 50S...
PERHAPS SOME UPPER 50S IN URBAN NORTHEAST NJ AND PARTS OF THE CT
RIVER VALLEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
UPPER RIDGE MOVES EAST TONIGHT WITH SURFACE HIGH OVER THE CANADIAN
MARITIMES. SURFACE LOW SHIFTS TO THE SOUTHEAST COAST. CLOUDS BEGIN
TO MOVE IN FROM THE SOUTH AS THE LOW DEEPENS AND TRACKS NORTH.
WITH THAT...AND NORTHEASTERLY FLOW...TEMPERATURES ALONG THE COAST
NOT EXPECTED TO FALL OFF TOO MUCH...AND INLAND TEMPERATURES TO
FALL OFF UNDER MOSTLY CLEAR SKIES...SO WILL BE LARGE CONTRAST.
MONDAY PRECIPITATION FROM THE COASTAL LOW MOVES IN FROM SOUTH TO
NORTH. GOOD AGREEMENT WITH BRINGING LIGHT RAIN INTO THE AREA
MONDAY MORNING INTO THE AFTERNOON. BEST CHANCES WILL BE MONDAY
NIGHT INTO TUESDAY AS BEST ISENTROPIC LIFT MOVES INTO THE AREA.
HAVE RAISED POPS TO LIKELY. TUESDAY BEST LIFT STARTS TO SHIFT EAST
AND LOWER POPS TUESDAY INTO TUESDAY NIGHT. GFS A LITTLE FASTER AND
DEEPER WITH THE SURFACE LOW TUESDAY INTO TUESDAY NIGHT AND LEANED
TOWARD THE SREF AND NAM. HEAVIEST PRECIPITATION LIKELY ACROSS
SOUTHEASTERN CONNECTICUT AND INTO LONG ISLAND WITH AREA OF BEST LIFT.
WITH CLOUD COVER...PRECIPITATION...AND EASTERLY WINDS WILL NOT SEE
A LARGE RANGE IN LOWS AND HIGHS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
RIDGING BUILDS BRIEFLY BETWEEN SYSTEMS WEDNESDAY...WITH LOW
DEPARTING TO THE EAST AND NEXT SYSTEM APPROACHING FROM THE WEST.
HAVE DECIDED TO KEEP SLIGHT CHANCE POPS TUESDAY NIGHT WITH SOME
UNCERTAINTY AS TO TIMING OF LOWS.
SOUTHWEST FLOW ALOFT DEVELOPS WEDNESDAY AS H5 LOW DROPS INTO THE OHIO
VALLEY. H3 JET PRODUCES SOME LIFT...BUT FORCING OTHERWISE IS WEAK
AS EVIDENCED BY THE TIME HEIGHTS. WITH MARGINAL MOISTURE...ONLY
LIGHT PRECIPITATION EXPECTED AT THIS TIME. FOCUS SHIFTS TO LATE
THURSDAY AND FRIDAY. ANOTHER H5 LOW DROPS INTO THE OHIO VALLEY
WITH A COMPLEX REFLECTION AT THE SURFACE. MODELS HINT AT LOW
PRESSURE DEVELOPING ALONG THE NORTHERN GULF COAST AND TRACKING
NORTHEASTWARD OFF THE ATLANTIC COAST...WITH A SECOND LOW
DEVELOPING OVER THE EASTERN GREAT LAKES. ALL THOUGH THERE IS A
SPREAD IN THE MODEL SOLUTIONS...IT APPEARS A SHOT OF RA ON TRACK
DURING THE PERIOD. MAIN ISSUE MAY TURN OUT TO BE THE WIND IF THE
12Z GFS/ECMWF SOLUTIONS ARE CLOSE AND A 980 MB LOW OCCLUDES OVER
NORTHERN NEW ENGLAND SATURDAY MORNING.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
VFR THROUGH THIS AFTERNOON. SKC..EXCEPT FOR A PESKY PATCH OF ST
AT ABOUT 2500 AGL. IF IT HOLDS TOGETHER...IT WOULD MOVE THROUGH
JFK/LGA AT ABOUT 17Z. CURRENT SAT IMAGERY INDICATE THAT IT IS
BREAKING UP...SO WILL LEAVE OUT OF THE 15Z TAF UPDATE FOR NOW.
INCREASED WIND SPEEDS WITH THE 15Z UPDATE...BASED ON CENTER FIELD
WIND REPORTS FROM KEWR.
OUTLOOK 12Z MONDAY THROUGH THURSDAY...
MONDAY THRU TUESDAY PM...SUB-VFR...PDS OF IFR LIKELY. GUSTY E-NE
WINDS.
TUESDAY NIGHT...BECOMING VFR.
WEDNESDAY...VFR.
WEDNESDAY NIGHT-THURSDAY...SUB-VFR POSSIBLE.
&&
.MARINE...
AT 15Z...BUOY 44025 HAD 4-FT SEAS WITH A STEADY 2.3-FT SWELL...AND
NE WINDS AROUND 17 KT. WIND SPEEDS/FETCH SHOULD INCREASE A LITTLE
THIS AFTERNOON AS HIGH PRESSURE BUILDS TO THE NORTH...SO THINK
5-FT SEAS ARE POSSIBLE BY MID TO LATE AFTERNOON FROM THERE
EAST...SO HAVE RAISED SCA A LITTLE SOONER E OF FIRE ISLAND INLET.
EXPECT SCA CONDITIONS WITH GUSTS TO 25-30 KT ON ALL WATERS TONIGHT
INTO MONDAY IN RESPONSE TO CONTINUED TIGHTENING PRESSURE GRADIENT
BETWEEN HIGH WEDGED INTO THE NORTHEASTERN US AND LOW PRESSURE
APPROACHING FROM THE S. SEAS ON THE OCEAN ZONES WILL BUILD TO 4 TO
8 FT BY MONDAY AS A RESULT OF STRENGTHENING NE FLOW.
DEPENDING ON EXACT TRACK/STRENGTH OF THE COASTAL LOW...THERE IS
THE POTENTIAL FOR GUSTS TO GALE FORCE ON THE OCEAN E OF FIRE
ISLAND INLET...AND POSSIBLY A LARGER AREA. FORECAST CONFIDENCE IS
NOT HIGH ENOUGH TO GO A WITH GALE WATCH...BUT WILL MENTION
OCCASIONAL GUSTS TO 35 KT AND EXTEND SCA ON COASTAL OCEAN WATERS
THROUGH MON NIGHT. STILL ENOUGH UNCERTAINTY ON LOW TRACK/STRENGTH
THAT NOT AS CONFIDENT OF SCA CONDITIONS OVER THE SOUND/HARBOR/BAYS
MONDAY NIGHT.
WINDS SHOULD SLOWLY DIMINISH TUE NIGHT AS LOW PULLS AWAY TO THE NE.
WHILE WINDS SHOULD FALL BELOW SCA LEVELS ON ALL WATERS TUE
NIGHT...OCEAN SEAS WILL LIKELY WILL REMAIN AT OR ABOVE SCA LEVELS
INTO THU.
WINDS SHOULD STAY BELOW SCA LEVELS WED INTO THU...WITH REGION IN
BETWEEN POTENTIALLY STRONG COASTAL STORMS.
&&
.HYDROLOGY...
DRY THROUGH MONDAY MORNING. QPF OF 1/2 NORTH/WEST TO 1 INCH
SOUTH/EAST IS POSSIBLE FROM MON AFTERNOON THROUGH WED.
ADDITIONAL PRECIPITATION IS POSSIBLE THU AND FRI. NO HYDROLOGIC
PROBLEMS ARE ANTICIPATED.
&&
.TIDES/COASTAL FLOODING...
DEPARTURES OF 2.0-2.5 FT AND 2.5-3.0 FT ARE NEEDED FOR THE
HIGHER/LOWER HIGH TIDE CYCLES ON MON/TUE TO PRODUCE MINOR COASTAL
FLOODING. CURRENT GUIDANCE FORECASTS DEPARTURES OF 0.5-1.0 FT...
BUT IS BASED ON A TRACK THAT BOTH FASTER AND FARTHER OUT TO SEA
THAN CURRENT THINKING. EVEN SO...A SLOWER/CLOSER LOW TRACK MAY
STILL NOT PRODUCE DEPARTURES LARGE ENOUGH TO CAUSE COASTAL
FLOODING. THIS WILL CONTINUE TO BE MONITORED CLOSELY.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 5 PM EST MONDAY
FOR ANZ330-335-338-340-345.
SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 6 AM EST
TUESDAY FOR ANZ350-353.
SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EST
TUESDAY FOR ANZ355.
&&
$$
000
FXUS61 KBOX 221603
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
1103 AM EST SUN NOV 22 2009
.SYNOPSIS...
HIGH PRESSURE EXTENDING FROM NEW YORK STATE INTO QUEBEC WILL MOVE
ACROSS NORTHERN NEW ENGLAND INTO THE MARITIMES TONIGHT...THEN EAST
OF NOVA SCOTIA MONDAY. LOW PRESSURE WILL BRING RAIN TO THE REGION
LATE MONDAY INTO TUESDAY. WEAK HIGH PRESSURE WILL TEMPORARILY BUILD
INTO THE REGION TUESDAY NIGHT INTO WEDNESDAY NIGHT THEN MOVE OFFSHORE
THANKSGIVING DAY. ANOTHER LOW PRESSURE SYSTEM WILL MOVE UP THE COAST
LATE THURSDAY AND FRIDAY BRINGING A CHANCE OF MORE RAIN. COLDER
BLUSTERY WEATHER IS FORECAST FOR SATURDAY BEHIND THAT DEPARTING LOW.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRES ACROSS NY STATE INTO EASTERN CANADA WILL SLOWLY MOVE NE
TODAY. THIS WILL INSURE MOSTLY CLEAR SKIES FOR MOST INTERIOR
LOCATIONS. LATEST SATELLITE IMAGERY SHOWING AREAS OF LOW CLOUDS
DEVELOPING OVER THE OCEAN AND MOVING SOUTHWEST. IT WILL BE A CONTEST
BETWEEN THE MARINE LAYER INTRUDING INTO SOUTHEAST MA AND THE LATE
NOVEMBER SUNSHINE. CURRENT THINKING IS CLOUDS WILL LINGER PRIMARILY
ALONG THE COASTAL PLAINS OF SOUTHEAST MA AND RI FOR TODAY.
CURRENT FORECAST TEMPERATURES ARE REASONABLE...BUT DID MAKE A FEW
TWEAKS TO REFLECT OBSERVED TRENDS. NO MAJOR CHANGES EXPECTED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
TONIGHT...HIGH PRESSURE WILL CONTINUE TO SHIFT NE ACROSS NOVA
SCOTIA. THIS...ALONG WITH LOW PRES DEVELOPING OFF THE MID ATLC COAST
WILL CAUSE A TIGHTENING PRES GRADIENT...SLOWLY INCREASING THE E-NE
WIND ESPECIALLY ALONG THE COAST. HAVE UPDATED THE FORECAST TO SHOW
LOW CLOUD COVER OVERSPREADING THE MAJORITY OF SOUTHERN NEW ENGLAND
OVERNIGHT.
OVERNIGHT LOWS WILL FALL BACK TO THE 30S TO AROUND 40...THOUGH MOS
GUIDANCE MAY BE A BIT TOO COLD CONSIDERING THE INCREASING CLOUDS AND
ONSHORE WIND...MAINLY S OF THE MASS PIKE.
MONDAY...CONDITIONS WILL DETERIORATE DURING THE DAY AS THE LOW
STARTS TO SLOWLY WORK NE. MODELS TRY TO BRING PRECIP INTO THE REGION
DURING THE DAY...WITH THE CANADIAN GEM MODELS BEING THE MOST
AGGRESSIVE. WITH THE STRONG HIGH TO THE N...FEEL THE DRY AIR MASS
OVER THE REGION WILL HOLD THE PRECIP OFF THROUGH AT LEAST MIDDAY...
AND PROBABLY NOT UNTIL NIGHTFALL OR AFTER ACROSS N MA/S NH. HAVE
BROUGHT CHANCE POPS INTO SOUTHERN AREAS DURING THE AFTERNOON AS THE
AIR MASS MOISTENS UP WITH THE ONSHORE FLOW AS WELL AS THE PRECIP
WORKING UP THE COAST.
WITH THE ONSHORE FLOW CONTINUING TO INCREASE AND THE APPROACHING
PRECIP...EXPECT DAYTIME HIGHS ONLY IN THE UPPER 40S TO MID 50S...
BUT THIS WILL STILL BE UP TO 5 DEGREES ABOVE SEASONAL NORMS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MONDAY NIGHT AND TUESDAY...
MODELS NOW ALL IN LINE WITH LOW PRESSURE MOVING FROM SOUTH OF
NANTUCKET MONDAY EVENING TO NEAR NOVA SCOTIA LATE TUESDAY NIGHT.
RAIN WILL MOVE ACROSS THE REGION FROM SOUTH TO NORTH MONDAY EVENING.
RGEM IS FASTEST OF 00Z MODELS RUNS WITH PRECIP IN RI AND CT BEFORE
7 PM MON. 00Z GFS WAS CONSIDERED OUTLIER WITH THE LOW TOO FAR OFF
THE COAST AND LITTLE RAINFALL OVER LAND. ECMWF TIMING AND PRECIP WAS
THE BASIS FOR THIS FORECAST. NEW 06Z GFS RUN NOW IS MORE IN
LINE...EVEN THOUGH ITS LOW IS STILL FARTHER EAST THAN THE OTHER
MODELS...IT NOW HAS RAIN AS FAR NORTH AS THE CT/RI/MA BORDER BY
MON EVENING. HAVE INCREASED POPS TO 60 PERCENT NORTHWEST AND
90 PERCENT SOUTHEAST.
IN GENERAL...0.5 INCHES OF RAIN IS EXPECTED IN MANY AREAS. HOWEVER...
THE COMBINATION OF STRONG MOIST ESE FLOW AT 925 MB OVERRUNNING
LESSER NE FLOW AT THE SURFACE WILL LEAD TO THE POTENTIAL FOR LOCALLY
HEAVY SHOWERS BETWEEN MIDNIGHT AND NOON TUESDAY. BEST CHANCE IS
ALONG EASTERN MA COAST. GFS SHOWS MORE THAN 2 INCHES OF RAIN OVER
THE OPEN WATERS...THIS WILL NEED TO BE WATCHED IN CASE HEAVY RAIN
OCCURS OVER THE COASTAL AREAS.
DESPITE PERSISTENT ONSHORE FLOW MONDAY/TUESDAY...ASTRONOMICAL TIDES
ARE LOW AND THE SYSTEM DOES NOT APPEAR INTENSE ENOUGH TO RESULT IN
ANY COASTAL FLOODING. HOWEVER...MINOR BEACH EROSION CERTAINLY IS
POSSIBLE.
STUCK WITH PREVIOUS FORECAST HIGH TEMPERATURES SINCE THEY WERE
SIGNIFICANTLY COOLER THAN GFS GUIDANCE. CONFIDENCE IS HIGH THAT IT
WILL BE COOL AND RAW DURING THE AFTERNOON WITH THE ONSHORE FLOW.
TUESDAY NIGHT AND WEDNESDAY...
LOW PULLS OUT TO THE EAST AND WEAK HIGH PRESSURE MOVES IN.
THE PROBLEM IS THAT THERE WILL STILL BE ABUNDANT LOW LEVEL MOISTURE.
925 MB RELATIVE HUMIDITY REACHES 90-100 PERCENT WED AFTERNOON.
HAVE GONE WITH CLOUDY FORECAST. REDUCED CHANCE OF SHOWERS TO 20 TO 30
PERCENT IN NW HALF OF AREA BECAUSE GFS SHOWED A WEAK VORTICITY MAX
MOVING THROUGH IN THE FAST SW FLOW ALOFT. SHOULD BE LIGHT IF ANYTHING
DUE TO DRYING AIR ALOFT. HIGHS SHOULD MAINLY BE FROM 50 TO 55.
WEDNESDAY NIGHT THROUGH THANKSGIVING...
MORE OF THE SAME...GENERALLY MOSTLY CLOUDY SKIES DUE TO LOW LEVEL
MOISTURE AS FLOW REMAINS EASTERLY BEHIND DEPARTING WEAK HIGH PRESSURE
AND AHEAD OF DEVELOPING LOW PRESSURE OFF THE CAROLINA COAST. HAVE LOW
PROBABILITIES OF SHOWERS...BUT IT MAY TURN OUT TO BE MORE OF A
CHANCE OF DRIZZLE ACROSS THE AREA. LOWS MID 30S TO LOWER 40S AND
HIGHS IN THE 50S.
THURSDAY NIGHT THROUGH FRIDAY NIGHT...
A VIGOROUS UPPER LEVEL TROUGH DEVELOPING FROM THE GREAT LAKES TO THE
OHIO VALLEY WILL INTENSIFY THE CAROLINA LOW PRESSURE SYSTEM AS IT
MOVES NORTHWARD UP THE EAST COAST. 00Z GFS DEEPENS IT TO 973 MB OVER
NEW ENGLAND COMPLETE WITH LOTS OF THUNDER ETC. 06Z GFS CONTINUES THIS
FORECAST WITH 974 MB. THESE WERE CONSIDERED TOO DEEP AS ECMWF REMAINS
CONSISTENT WITH 998 MB WHICH IS WEAKER THAN ITS PREVIOUS RUN OF 993
MB. THE PLACEMENT OF THIS STORM WILL DETERMINE WHERE THE HEAVIEST
RAIN WOULD FALL. RIGHT NOW...WE HAVE ADDED 50 TO 60 PERCENT POPS TO
THE FORECAST FROM LATE THU NIGHT THROUGH FRIDAY...DIMINISHING
SOMEWHAT FRI NIGHT. IT SHOULD BE NOTED THAT THE CANADIAN GGEM MODEL
IS DRY THROUGHOUT FRIDAY. THUS AT THIS TIME...CONFIDENCE IS ONLY MEDIUM
THAT A STORM WILL FORM...AND EVEN LOWER AS TO ITS PLACEMENT.
SATURDAY...BLUSTERY AND CHILLY WEATHER LOOKS TO BE FILTERED INTO
THE REGION BEHIND THE SYSTEM. WITH THE UPPER LOW PRESSURE DIRECTLY
OVERHEAD...EXPECT RATHER UNSTABLE CONDITIONS WHICH COULD LEAD TO A
FEW RAIN SHOWERS IN THE SOUTH AND EAST AND SNOW SHOWERS IN THE
NORTHWEST...ESPECIALLY IN THE HIGHER TERRAIN. IT WILL BE TOO WARM AT THE
SURFACE FOR ANY ACCUMULATION. HIGHS ARE FORECAST TO BE IN THE UPPER
30S NORTHWEST TO MID 40 SOUTHEAST.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
THIS AFTERNOON...VFR. LOCAL MVFR CIGS GENERALLY SOUTH AND EAST OF A
LINE FROM KLWM-KPVD DUE TO AREAS OF MARINE STRATUS MOVING ONSHORE.
TONIGHT...VFR MOST LOCATIONS. WILL LIKELY SEE MVFR CIGS MOVING IN
ALONG THE COAST S AND E OF A LINE FROM KBOS-KPVD...MAINLY NEAR OR
AFTER MIDNIGHT. WILL ALSO SEE E-NE WINDS INCREASE ACROSS CAPE COD
AND THE ISLANDS.
MONDAY...EXPECT VFR CIGS MAINLY N OF ROUTE 2 ACROSS N MA...WHILE
CONDITIONS LOWER TO MVFR-IFR CIGS S OF THERE. LOCAL IFR CIGS ALONG
THE S COAST...CAPE COD AND THE ISLANDS DURING THE AFTERNOON. PATCHY
RAIN WILL APPROACH N CT/RI/SE MA DURING THE AFTERNOON WITH LOCAL
MVFR VSBYS.
OUTLOOK /MONDAY NIGHT THROUGH FRIDAY/...
MONDAY NIGHT AND TUESDAY...IFR CONDITIONS IN LOW CLOUDS...RAIN AND
FOG. LOCALLY HEAVIER SHOWERS MAINLY EASTERN SECTIONS.
TUE NIGHT THROUGH THU...MVFR-IFR CONDITIONS MAY LINGER IN LOW
CLOUDS THROUGH THIS PERIOD. ONLY SLIGHT CHANCE OF A RAIN SHOWER BUT
MAY HAVE AREAS OF DRIZZLE AND FOG DEVELOPING...ESPECIALLY WED NIGHT.
THU NIGHT AND FRI...LOW TO MEDIUM CONFIDENCE OF IFR CEILINGS AND
VSBYS IN SHOWERS.
&&
.MARINE...
TODAY...NE WINDS WILL GRADUALLY INCREASE DURING THE DAY. WITH THE
INCREASING WIND AND ONSHORE FETCH...EXPECT SEAS TO BUILD UP TO 5 FT
MAINLY ON THE EASTERN OUTER WATERS. HAVE CONTINUED SMALL CRAFT
ADVISORY.
TONIGHT...AS LOW PRES WORKS UP THE COAST...WILL SEE E-NE WINDS
CONTINUE TO INCREASE. EXPECT WIND GUSTS UP TO 25 KT...MAINLY ON THE
SOUTHERN WATERS. SEAS WILL CONTINUE TO BUILD ON MOST OF THE
WATERS...SO HAVE PUT UP SMALL CRAFTS LATE TONIGHT FOR THE S SOUNDS.
MONDAY...E-NE WIND GUSTS UP TO 30 KT ON THE OUTER WATERS. SEAS
CONTINUE TO BUILD...POSSIBLY UP TO 8 FT WELL OFFSHORE.
OUTLOOK /MONDAY NIGHT THROUGH THURSDAY/...
MONDAY NIGHT THROUGH EARLY WEDNESDAY...LOW PRESSURE PASSING FROM
SOUTH OF NANTUCKET TO NOVA SCOTIA WILL CREATE A PERSISTENT NORTHEAST
FLOW AND GOOD GRADIENT. THIS WILL RESULT IN SCA ACROSS MOST OF OUR
WATERS OVER THIS TIME PERIOD. SEAS MAY BUILD TO BETWEEN 7 AND 12 FEET
ACROSS THE OUTER WATERS. THERE IS A LOW PROBABILITY OF BRIEF
MARGINAL GALE FORCE GUSTS MAINLY VERY LATE MON NIGHT OR ON TUESDAY
OVER THE SOUTHERN WATERS.
WEDNESDAY THROUGH THANKSGIVING...WINDS WILL CONTINUE FROM A
PERSISTENT EASTERLY DIRECTION PERHAPS BECOMING SOUTHEAST LATER THU.
THIS WILL LIKELY CAUSE SEAS TO REMAIN ABOVE SCA THRESHOLDS ACROSS THE
OUTER-WATERS. WINDS AND SEAS MAY ONCE AGAIN INCREASE VERY LATE
THANKSGIVING NIGHT IN ADVANCE OF THE NEXT SYSTEM APPROACHING FROM THE
SOUTH.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 5 AM TO 5 PM EST MONDAY FOR
ANZ232>235-237.
SMALL CRAFT ADVISORY UNTIL 5 PM EST MONDAY FOR ANZ250-254>256.
&&
$$
SYNOPSIS...EVT/GAF
NEAR TERM...BELK/GAF
SHORT TERM...EVT
LONG TERM...GAF
AVIATION...BELK/GAF
MARINE...EVT/GAF
000
FXUS61 KALY 221543
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
1043 AM EST SUN NOV 22 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL COVER THE NORTHEAST TO START THE
WEEK. IT WILL SLIDE EAST INTO THE MARITIMES AND OFFSHORE LATE MONDAY.
OUR WEATHER WILL TURN UNSETTLED MUCH OF THE UPCOMING WEEK. THE FIRST
LOW PRESSURE AREA WILL MOVE NORTHEAST FROM THE CAROLINA COAST
OFFSHORE MONDAY NIGHT AND TUESDAY. THEN MIDWEEK A SERIES OF MUCH
STRONGER STORMS WILL MOVE THOUGH THE MIDWEST AND GREAT LAKES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MOISTURE IS CONTINUING TO BE TRAPPED UNDER AN INVERSION...AND
CLOUD COVER EXTENDS FROM THE NY AND NEW ENGLAND BORDER WESTWARD
ACROSS NY AND NORTHERN PA. BASED ON UPSTREAM CONDITIONS...AND
LIGHT WIND FLOW THROUGH THE BOUNDARY LAYER...CLOUD COVER SHOULD
PERSIST MUCH OF THE DAY. SOME SLIGHT EROSION SEEN IN WESTERN NEW
ENGLAND PERHAPS SLOWLY BUILDING WEST DURING THE DAY...BUT MIX OF
CLOUDS AND SUN LIKELY FROM PSF TO AQW AND DDH...RIGHT ALONG THE
EDGE OF THE CLOUDS. SOME DEEPER SUBSIDENCE SHOULD BUILD INTO THE
REGION TOWARD AND THROUGH THE EVENING...SO ACKNOWLEDGING SOME
BETTER EROSION TO THE CLOUDS FROM EAST TO WEST LATE THIS AFTERNOON
AND EVENING. SO...SOME BREAKS IN THE CLOUDS ARE POSSIBLE FROM THE
HUDSON VALLEY LATE THIS AFTERNOON OR AROUND SUNSET. NUDGED HIGH
TEMPERATURES DOWN A DEGREE OR TWO BASED ON THE CLOUD COVER...WHICH
WAS EXPANDED. THE REST OF THE FORECAST REMAINS UNTOUCHED.
PREV AFD BELOW...
MOISTURE TRAPPED BENEATH LOW LEVEL SUBSIDENCE INVERSION WILL KEEP
PATCHY LOW CLOUDS AROUND THROUGH AT LEAST LATE THIS MORNING. IN
FACT...WHERE SOME BREAKS HAVE DEVELOPED...CLOUDS MAY ACTUALLY
REDEVELOP AROUND OR JUST AFTER SUNRISE ONCE SHALLOW MIXING
DEVELOPS. EVENTUALLY...AS THE LOW LEVEL FLOW VEERS INTO A MORE NE
DIRECTION...SOME DOWNSLOPING OFF THE HIGHER TERRAIN TO OUR N/E
SHOULD ALLOW FOR MORE BREAKS IN THE CLOUDS TO DEVELOP THIS
AFTERNOON...ESP FROM THE HUDSON RIVER VALLEY EASTWARD. CLOUDS MAY
PERSIST LONGER...PERHAPS WELL INTO THE AFTERNOON...ACROSS WESTERN
PORTIONS OF THE REGION...FROM THE SW DACKS...WESTERN MOHAWK VALLEY
INTO THE SCHOHARIE VALLEY AND NE CATSKILLS.
AS FOR MAX TEMPS...GIVEN THE EXPECTATION FOR SHALLOW MIXING...MAINLY
TO 925-950 MB...WE EXPECT MAXES TO BE A BIT COOLER THAN SAT...ESP
GIVEN A SLIGHTLY COLDER START...ALONG WITH THE EXPECTATION FOR
CLOUDS THROUGH THE MORNING. SO...GENERALLY SIDED CLOSE TO THE COOLER
MET MOS...WITH MAXES GENERALLY REACHING AROUND 50 WITHIN MUCH OF THE
HUDSON RIVER VALLEY...EXCEPT LOWER/MID 50S ACROSS THE MID HUDSON
VALLEY...WITH MAINLY 40S ACROSS HIGHER ELEVATIONS WITHIN WESTERN NEW
ENGLAND AND WESTERN PORTIONS OF THE REGION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
PERIOD STARTS WITH RIDGING AND SUBSIDENCE THROUGHOUT THE
ATMOSPHERE WITH 572DM HIGH EVEN AT 500HPA. 500HPA TROF LINGERS
SOUTH OF RGN FM MASON DIXON LINE TO LONG IS NY WHILE IMPRESSIVE
SFC HIGH DOMINATES THE NORTHEAST QUARTER OF THE NATION AND IS
CENTERED OVER THE MARITIMES. WHILE THE DIRTY HIGH PHASE WITH
MOISTURE TRAPPED UNDER THE INVERSION WILL HAVE ENDED EARLY SUNDAY
THE NEW GUIDANCE SUGGESTS THE MOIST BOUNDARY LAYER REMAINS AND
SHOWS MARINE LAYER MOISTURE OR FOG/STRATUS CREEPING BACK UP THE
HUDSON VALLEY EVEN AS EARLY AS LATE SUNDAY NIGHT EARLY MONDAY
MORNING. THE WITH ALL THE MODELS AND STATISTICAL GUID KEEPING THE
FLOW EAST TO NORTHEAST BELOW THE INVERSION LAYER...WILL BRING
CLOUDS INTO THE SOUTHEAST. THE NAM IS THE ONLY LESS AGGRESSIVE
MODEL WITH ADVECTING THIS MARINE LAYER MOISTURE WHILE THE
WRF/GEM/GFS SHOW IT BLO 900HPA.
MUCH LIKE LAST WEEK WHEN THIS SAME SCENARIO OCCURRED CLOUDS SHOULD
BARELY MAKE ALBANY MONDAY MORNING AND THESE MAY ERODE FOR A TIME.
FROM ALB N & W WILL STAY FAIR A GOOD PART OF THE DAY TILL BOUNDARY
LEVEL FLOW TURNS SE-S AND MOISTURE STREAMS NORTH. IN SOUTHEAST
LOOKING AT AREAS OF MORNING STRATUS AND FOG THAT MAY OR MAY NOT
BURN OFF BEFORE THE CLOUDS FROM NEXT SYSTEM OVERSPREAD THOSE
AREAS.
MARINE LAYER MOISTURE ADVECTION SHOULD BE WEAK TILL 500HPA TROF
THAT WAS LAYING DORMANT ACROSS THE MID ATLC BEGINS MOVES NORTH
INTO OUR REGION MONDAY. MODELS SUGGEST A COASTAL DEVELOPMENT BUT
ITS WELL OFFSHORE AND ITS MAIN IMPACT IS TO ENHANCE THE MARINE
LAYER INFLOW. THIS MOISTURE AND THE PASSAGE OF SEVERAL 500HPA
SHORT WAVES WILL PRODUCE CLOUDS ACROSS THE AREA AND AN INCR CHC
OF -RN AND DZ MONDAY NIGHT AND TUES MAINLY IN THE SOUTHEAST.
INITIALLY TUESDAY NIGHT THE SFC LOW DEPARTS WELL OFFSHORE. 500HPA
RIDGE REBUILDS ALONG THE SEABOARD. WELL TO OUR WEST THE STAGE IS
BEING SET FOR A COMPLEX PATTERN TO END THE WEEK. TUES NT WERE
STUCK WITH MORE RESIDUAL LOW LEVEL MOISTURE AND NOT MUCH MORE THAN
DRIZZLE AND CLOUDS.
MEANWHILE TUESDAY NIGHT TWO CUTOFFS WILL BE SETTING UP. ONE IN
THE MISSISSIPPI VALLEY THE OTHER IN SOUTH CENTRAL CANADA. LOOKING
AT THE 1.5PVU SFCS THE ORIGINS OF THESE SYSTEMS ARE THREE
PART. 1) JUST OFF THE BRITISH COLUMBIA ALASKA PANHANDLE
COAST...2) IN THE FAST FLOW IN THE CENTRAL PACIFIC NORTH OF
HAWAII AND 3) ALONG ALASKA`S BROOKS RANGE. OBVIOUSLY MANY
QUESTIONS REMAIN ABOUT THE PHASING PROCESS AND THE RESULTANT SFC
WEATHER. MORE IN THIS IN LONG TERM SECTION.
THROUGH TUESDAY NIGHT THERES A FAIR AMOUNT OF MODEL CONSISTENCY
EXCEPT WITH REGARD TO THE MAGNITUDE OF THE MARINE LAYER INFLOW
MONDAY AS DISCUSSED ABOVE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE LONG RANGE FORECAST PERIOD IS THE RESULT OF THE ORGANIZATION OF
TWO MAJOR CUT OFFS AND THEIR INTERACTION AND EVENTUAL MERGER. GIVEN
THE LOCATIONS OF THE VORTICITY THAT WILL GIVE RISE TO THIS SCENARIO
(GIVEN AT END OF SHORT TERM)...MUCH REMAINS UNCERTAIN AND SUBJECT
TO CHANGE BASED ON THE PHASING TIME...DEGREE...LOCATION AND THEN THE
ULTIMATE SFC RESPONSE.
THERE ARE SOME GENERAL THEMES IN MOST OF THE GUIDANCE. ONE CUT
OFF OVER THE MID WEST LIFTS NORTHEAST INTO THE RIDGE OVER THE
EASTERN SEABOARD WEDNESDAY. THE SECOND DIVES SOUTH OUT OF CENTRAL
CANADA. THEY DUMBBELL AROUND EACH OTHER AND MERGE BY THEN END OF
THE WEEK. HWVR POSITIONS RANGE FM CENTERED N OF YUL (GEM)..TO NJ
(GFS) TO OHIO (ECMWF).
WHAT IS MOST CONCRETE AT THIS POINT IS WEDNESDAY THE FIRST 500HPA
CUT OFF MOVES FM MIDWEST INTO GRT LAKES AND PUSHES AN OCCLUDED
FRONT INTO NYS LATE IN THE DAY. THE GFS/GEM AND ECMWF SHOW THIS
SCENARIO WITH THAT CANADIAN ABOUT 6 HOURS FASTER WITH PCPN. WILL
KEEP IT DRY IN THE MORNING WITH CHC POPS AFTN AND WED NIGHT.
THE TIMING ISSUES BECOME MORE ACUTE FROM THURSDAY ON. THURSDAY
THE GFS PUTS FCA IN DRY SLOT AHEAD OF NEXT FRONTAL SYSTEM PUSHING
ACROSS FCA. THE GEM/ECM BRING THE NEXT FRONTAL SYSTEM THROUGH.
IN SUMMARY THE LONG RANGE PERIOD GENERAL THEMES ARE FAIRLY
CLEAR...BUT TIMING IS ALL OVER. OTHER THAN WED WILL LEAVE MUCH OF
THE EARLIER HPC BASED LONG RANGE IN PLACE WITH JUST SOME TWEAKS TO
IMPROVE COORDINATION. TO CHANGE IT TO GMOS AT THIS TIME WILL JUST
INCREASE THE FLIP FLOP FACTOR.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
MVFR LEVEL CLOUDS HAVE REDEVELOPED AT KGFL AND KALB. WE EXPECT THESE
CLOUDS TO PERSIST UNTIL AROUND 15Z...BEFORE GRADUALLY
LIFTING/ERODING. THERE IS A SMALL CHANCE OF IFR LEVEL CLOUDS TO
DEVELOP BENEATH THIS DECK...ESP AT KGFL...PRIOR TO 15Z...AND HAVE
INDICATED A TEMPO AT KGFL DUE TO THIS POSSIBILITY. CONDITIONS SHOULD
IMPROVE TO VFR AFTER 15Z...WITH VFR CONDITIONS PERSISTING THROUGH AT
LEAST MIDNIGHT TONIGHT. THEREAFTER...A LOW STRATUS DECK MAY ADVECT
NORTHWARD...UP THE HUDSON RIVER VALLEY...AFTER 08Z/MON. WE HAVE
INDICATED MVFR CONDITIONS...MAINLY FOR CIGS...TO DEVELOP FROM S TO N
TOWARD DAYBREAK. SOME IFR CIGS ARE POSSIBLE AT KPOU...BUT CONFIDENCE
LOW ENOUGH AT THIS TIME RANGE TO KEEP LOW MVFR AT KPOU.
WINDS WILL REMAIN LIGHT...MAINLY FROM THE NE TO E AT 5-10 KT TODAY.
WINDS WILL THEN BECOME LIGHT/VARIABLE TONIGHT.
OUTLOOK...
MON-TUE...VFR-MVFR...CHC OF RAIN MON NT-TUE.
WED...VFR...CHC OF SHOWERS.
THU...MVFR/IFR...RAIN POSSIBLE LATE.
&&
.HYDROLOGY...
WITH DRY CONDITIONS EXPECTED TO LAST AT LEAST INTO MONDAY RIVERS
WILL CONTINUE RECEDE THROUGH MONDAY. THE NEXT THREAT OF RAIN WILL
BE LATE MONDAY INTO TUESDAY. CONSENSUS OF MODELS IS FOR 0.10 TO
0.30 INCHES MAINLY IN THE SOUTHEAST. THIS EVENT SHOULD HAVE MODEST
IMPACT ON RIVERS AND STREAMS. FURTHER OUT AN UNSETTLED PERIOD OF
WEATHER THURSDAY INTO THE WEEKEND COULD RESULT IN SIGNIFICANT
PRECIPITATION AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...NAS
NEAR TERM...NAS
000
FXUS61 KOKX 221528
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1028 AM EST SUN NOV 22 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER THE NORTHEASTERN UNITED STATES AND
THE CANADIAN MARITIME PROVINCES THROUGH MONDAY...THE SLIDE EAST
INTO MIDWEEK. MEANWHILE AN AREA OF LOW PRESSURE WILL MOVE FROM THE
GULF COAST TO THE SOUTHEAST COAST TODAY AND MONDAY. THE LOW TRACKS
ALONG THE SEABOARD THROUGH TUESDAY...REACHING THE CANADIAN
MARITIMES WEDNESDAY. WEAK HIGH PRESSURE BUILDS DOWN FROM THE
NORTH WEDNESDAY...BEFORE RETREATING TO THE EAST WEDNESDAY NIGHT AS
A COMPLEX STORM SYSTEM APPROACHES FROM THE WEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RIDGE REMAINS OVER THE AREA THROUGH TODAY AS SURFACE HIGH BUILDS
ACROSS SOUTHEASTERN CANADA. WINDS SHIFT FROM THE NORTH TO THE
NORTHEAST IN RESPONSE TO THE HIGH. AREA OF STRATO CU JUST TO THE
NORTH OF THE LOWER HUDSON VALLEY AND INTO NORTHEASTERN
PENNSYLVANIA NOT MAKING ANY PROGRESS TO THE SOUTH...AND WILL
LIKELY REMAIN NORTH OF THE AREA. DESPITE SUNSHINE...EASTERLY FLOW
WILL KEEP TEMPERATURES IN THE LOWER TO MID 50S ACROSS THE REGION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
UPPER RIDGE MOVES EAST TONIGHT WITH SURFACE HIGH OVER THE CANADIAN
MARITIMES. SURFACE LOW SHIFTS TO THE SOUTHEAST COAST. CLOUDS BEGIN
TO MOVE IN FROM THE SOUTH AS THE LOW DEEPENS AND TRACKS NORTH.
WITH THAT...AND NORTHEASTERLY FLOW...TEMPERATURES ALONG THE COAST
NOT EXPECTED TO FALL OFF TOO MUCH...AND INLAND TEMPERATURES TO
FALL OFF UNDER MOSTLY CLEAR SKIES...SO WILL BE LARGE CONTRAST.
MONDAY PRECIPITATION FROM THE COASTAL LOW MOVES IN FROM SOUTH TO
NORTH. GOOD AGREEMENT WITH BRINGING LIGHT RAIN INTO THE AREA
MONDAY MORNING INTO THE AFTERNOON. BEST CHANCES WILL BE MONDAY
NIGHT INTO TUESDAY AS BEST ISENTROPIC LIFT MOVES INTO THE AREA.
HAVE RAISED POPS TO LIKELY. TUESDAY BEST LIFT STARTS TO SHIFT EAST
AND LOWER POPS TUESDAY INTO TUESDAY NIGHT. GFS A LITTLE FASTER AND
DEEPER WITH THE SURFACE LOW TUESDAY INTO TUESDAY NIGHT AND LEANED
TOWARD THE SREF AND NAM. HEAVIEST PRECIPITATION LIKELY ACROSS
SOUTHEASTERN CONNECTICUT AND INTO LONG ISLAND WITH AREA OF BEST LIFT.
WITH CLOUD COVER...PRECIPITATION...AND EASTERLY WINDS WILL NOT SEE
A LARGE RANGE IN LOWS AND HIGHS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
RIDGING BUILDS BRIEFLY BETWEEN SYSTEMS WEDNESDAY...WITH LOW
DEPARTING TO THE EAST AND NEXT SYSTEM APPROACHING FROM THE WEST.
HAVE DECIDED TO KEEP SLIGHT CHANCE POPS TUESDAY NIGHT WITH SOME
UNCERTAINTY AS TO TIMING OF LOWS.
SOUTHWEST FLOW ALOFT DEVELOPS WEDNESDAY AS H5 LOW DROPS INTO THE OHIO
VALLEY. H3 JET PRODUCES SOME LIFT...BUT FORCING OTHERWISE IS WEAK
AS EVIDENCED BY THE TIME HEIGHTS. WITH MARGINAL MOISTURE...ONLY
LIGHT PRECIPITATION EXPECTED AT THIS TIME. FOCUS SHIFTS TO LATE
THURSDAY AND FRIDAY. ANOTHER H5 LOW DROPS INTO THE OHIO VALLEY
WITH A COMPLEX REFLECTION AT THE SURFACE. MODELS HINT AT LOW
PRESSURE DEVELOPING ALONG THE NORTHERN GULF COAST AND TRACKING
NORTHEASTWARD OFF THE ATLANTIC COAST...WITH A SECOND LOW
DEVELOPING OVER THE EASTERN GREAT LAKES. ALL THOUGH THERE IS A
SPREAD IN THE MODEL SOLUTIONS...IT APPEARS A SHOT OF RA ON TRACK
DURING THE PERIOD. MAIN ISSUE MAY TURN OUT TO BE THE WIND IF THE
12Z GFS/ECMWF SOLUTIONS ARE CLOSE AND A 980 MB LOW OCCLUDES OVER
NORTHERN NEW ENGLAND SATURDAY MORNING.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
VFR THROUGH THIS AFTERNOON. SKC..EXCEPT FOR A PESKY PATCH OF ST
AT ABOUT 2500 AGL. IF IT HOLDS TOGETHER...IT WOULD MOVE THROUGH
JFK/LGA AT ABOUT 17Z. CURRENT SAT IMAGERY INDICATE THAT IT IS
BREAKING UP...SO WILL LEAVE OUT OF THE 15Z TAF UPDATE FOR NOW.
INCREASED WIND SPEEDS WITH THE 15Z UPDATE...BASED ON CENTER FIELD
WIND REPORTS FROM KEWR.
OUTLOOK 12Z MONDAY THROUGH THURSDAY...
MONDAY THRU TUESDAY PM...SUB-VFR...PDS OF IFR LIKELY. GUSTY E-NE
WINDS.
TUESDAY NIGHT...BECOMING VFR.
WEDNESDAY...VFR.
WEDNESDAY NIGHT-THURSDAY...SUB-VFR POSSIBLE.
&&
.MARINE...
EXPECT CONDITIONS ON THE WATERS TO REMAIN BELOW SCA CONDITIONS ON
THE WATERS...THOUGH COULD SEE SOME OCCASIONAL GUSTS TO 25 KT LATE
THIS AFTERNOON ACROSS THE COASTAL OCEAN WATERS AS THE PRESSURE
GRADIENT BEGINS TO TIGHTEN (STRONGEST FURTHER S FROM LONG ISLAND
(FURTHEST FROM CENTER OF HIGH).
EXPECT GUSTS TO 25-30 KT ALL WATERS TONIGHT AND MONDAY IN RESPONSE
TO CONTINUED TIGHTENING PRESSURE GRADIENT BETWEEN HIGH WEDGED INTO
THE NORTHEASTERN US AND LOW PRESSURE APPROACHING FROM THE S. SEAS ON
THE OCEAN ZONES WILL BUILD TO 4 TO 8 FT BY MONDAY AS A RESULT OF
STRENGTHENING NE FLOW.
DEPENDING ON EXACT TRACK/STRENGTH OF COASTAL LOW THERE IS THE
POTENTIAL FOR GUSTS TO GALE FORCE OVER THE EASTERN TWO COASTAL OCEAN
ZONES (AND POSSIBLY A LARGER AREA)...NOT CONFIDENT ENOUGH TO GO WITH
GALE WATCH...BUT AM CONFIDENT ENOUGH TO MENTION OCCASIONAL GUSTS TO
35 KT AND EXTEND SCA ON COASTAL OCEAN WATERS THROUGH MONDAY NIGHT
(STILL ENOUGH UNCERTAINTY ON LOW TRACK/STRENGTH THAT NOT AS
CONFIDENT OF SCA CONDITIONS OVER THE SOUND/HARBOR/BAYS MONDAY NIGHT).
THE STRONG NE WINDS (POSSIBLY WITH GUSTS TO GALE FORCE OVER EASTERN
TWO COASTAL OCEAN ZONES (AND A CHANCE FOR EVEN GREATER COVERAGE)
WILL CONTINUE INTO TUESDAY...THEN SLOWLY DIMINISH TUE NIGHT AS LOW
PULLS AWAY TO THE NE. WHILE WINDS SHOULD FALL BELOW SCA LEVELS ON
ALL WATERS TUE NIGHT...THE SEAS OVER THE COASTAL OCEAN ZONES WILL
NOT. THESE SEAS LIKELY WILL REMAIN AT OR ABOVE SCA LEVELS INTO
THURSDAY.
WINDS SHOULD STAY BELOW SCA LEVELS WEDNESDAY-THURSDAY WITH REGION IN
BETWEEN POTENTIAL STRONG COASTAL STORMS.
&&
.HYDROLOGY...
DRY THROUGH MONDAY MORNING. A HALF INCH...NORTH AND WEST...TO ONE
INCH...SOUTHEAST...IS POSSIBLE FROM MONDAY AFTERNOON THROUGH
WEDNESDAY. ADDITIONAL PRECIPITATION IS POSSIBLE THURSDAY AND FRIDAY.
NO HYDROLOGIC PROBLEMS ARE ANTICIPATED.
&&
.TIDES/COASTAL FLOODING...
CURRENT COASTAL FLOODING GUIDANCE WOULD NOT SUGGEST ANY FLOOD
THREAT...HOWEVER IT IS BASED ON THE MODEL THAT IS FURTHEST OUT TO
SEA AND MOST PROGRESSIVE WITH THE COASTAL STORM MONDAY-WEDNESDAY. IF
STORM TAKES THE CURRENT CONSENSUS IDEA OF A TRACK THAT IS CLOSER TO
THE COAST AND SLOWER THAN THE MODEL USED TO MAKE THE STORM SURGE
FORECAST...WOULD SEE LARGER DEPARTURES THAN NORMAL THAN GUIDANCE
CURRENTLY SUGGESTS. FOR MINOR COASTAL FLOODING MONDAY-TUESDAY YOU
WOULD NEED DEPARTURES OF 2-2.5 FT ABOVE NORMAL FOR THE HIGHER OF THE
TWO HIGH TIDES AND 2.5-3 FT ABOVE NORMAL FOR THE LOWER OF THE TWO
HIGH TIDES. CURRENT GUIDANCE ONLY SUGGESTS DEPARTURES OF 0.5-1
FT...SO EVEN A SLOWER/CLOSER TO THE COAST SCENARIO MAY MOT PRODUCE
LARGE ENOUGH DEPARTURES TO CAUSE COASTAL FLOODING. THIS WILL
CONTINUE TO BE MONITORED CLOSELY.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 5 PM EST MONDAY
FOR ANZ330-335-338-340-345.
SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EST
TUESDAY FOR ANZ350-353-355.
&&
$$
SYNOPSIS...MET
NEAR TERM...MET
SHORT TERM...MET
LONG TERM...
AVIATION...BS
MARINE...PFM
HYDROLOGY...MET
TIDES/COASTAL FLOODING...
000
FXUS61 KBOX 221231
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
731 AM EST SUN NOV 22 2009
.SYNOPSIS...
HIGH PRESSURE EXTENDING FROM NEW YORK STATE INTO QUEBEC WILL MOVE
ACROSS NORTHERN NEW ENGLAND INTO THE MARITIMES TONIGHT...THEN EAST
OF NOVA SCOTIA MONDAY. LOW PRESSURE WILL BRING RAIN TO THE REGION
LATE MONDAY INTO TUESDAY. WEAK HIGH PRESSURE WILL TEMPORARILY BUILD
INTO THE REGION TUESDAY NIGHT INTO WEDNESDAY NIGHT THEN MOVE OFFSHORE
THANKSGIVING DAY. ANOTHER LOW PRESSURE SYSTEM WILL MOVE UP THE COAST
LATE THURSDAY AND FRIDAY BRINGING A CHANCE OF MORE RAIN. COLDER
BLUSTERY WEATHER IS FORECAST FOR SATURDAY BEHIND THAT DEPARTING LOW.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRES ACROSS NY STATE INTO EASTERN CANADA WILL SLOWLY MOVE NE
TODAY. THIS WILL INSURE MOSTLY CLEAR SKIES FOR MOST AREAS. SOME OF
THE MODELS...ESPECIALLY THE CANADIAN REGIONAL GEM...HAVE BEEN
HINTING AT LOW CLOUDS DEVELOPING OFFSHORE AND MOVING IN ALONG THE
COAST. THE RGEM TENDS TO HANDLE CLOUDS WELL. THIS TREND HAS CONTINUED
ON THE 06Z RUNS...SEEN BEST ON 925 MB RH FIELDS.
HAVE UPDATED THE SKY COVER CONDITIONS TO INDICATE PARTLY TO MOSTLY
CLOUDY SKIES MOVING INTO SOUTHEAST MA AND RI LATER THIS AFTERNOON...
AND THEN OVERSPREADING THE REGION TONIGHT.
AS LIGHT WINDS VEER AROUND TO N-NE...WILL SEE DAYTIME HIGHS ON THE
COOLER SIDE TODAY ESPECIALLY ALONG THE COAST. FORECASTING HIGHS
MAINLY IN THE LOWER-MID 50S...WHICH CONTINUED TO RUN UP TO 5 DEGREES
OR SO ABOVE NORMAL.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
TONIGHT...HIGH PRESSURE WILL CONTINUE TO SHIFT NE ACROSS NOVA
SCOTIA. THIS...ALONG WITH LOW PRES DEVELOPING OFF THE MID ATLC COAST
WILL CAUSE A TIGHTENING PRES GRADIENT...SLOWLY INCREASING THE E-NE
WIND ESPECIALLY ALONG THE COAST. HAVE UPDATED THE FORECAST TO SHOW
LOW CLOUD COVER OVERSPREADING THE MAJORITY OF SOUTHERN NEW ENGLAND
OVERNIGHT.
OVERNIGHT LOWS WILL FALL BACK TO THE 30S TO AROUND 40...THOUGH MOS
GUIDANCE MAY BE A BIT TOO COLD CONSIDERING THE INCREASING CLOUDS AND
ONSHORE WIND...MAINLY S OF THE MASS PIKE.
MONDAY...CONDITIONS WILL DETERIORATE DURING THE DAY AS THE LOW
STARTS TO SLOWLY WORK NE. MODELS TRY TO BRING PRECIP INTO THE REGION
DURING THE DAY...WITH THE CANADIAN GEM MODELS BEING THE MOST
AGGRESSIVE. WITH THE STRONG HIGH TO THE N...FEEL THE DRY AIRMASS
OVER THE REGION WILL HOLD THE PRECIP OFF THROUGH AT LEAST MIDDAY...
AND PROBABLY NOT UNTIL NIGHTFALL OR AFTER ACROSS N MA/S NH. HAVE
BROUGHT CHANCE POPS INTO SOUTHERN AREAS DURING THE AFTERNOON AS THE
AIRMASS MOISTENS UP WITH THE ONSHORE FLOW AS WELL AS THE PRECIP
WORKING UP THE COAST.
WITH THE ONSHORE FLOW CONTINUING TO INCREASE AND THE APPROACHING
PRECIP...EXPECT DAYTIME HIGHS ONLY IN THE UPPER 40S TO MID 50S...
BUT THIS WILL STILL BE UP TO 5 DEGREES ABOVE SEASONAL NORMS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MONDAY NIGHT AND TUESDAY...
MODELS NOW ALL IN LINE WITH LOW PRESSURE MOVING FROM SOUTH OF
NANTUCKET MONDAY EVENING TO NEAR NOVA SCOTIA LATE TUESDAY NIGHT.
RAIN WILL MOVE ACROSS THE REGION FROM SOUTH TO NORTH MONDAY EVENING.
RGEM IS FASTEST OF 00Z MODELS RUNS WITH PRECIP IN RI AND CT BEFORE
7 PM MON. 00Z GFS WAS CONSIDERED OUTLIER WITH THE LOW TOO FAR OFF
THE COAST AND LITTLE RAINFALL OVER LAND. ECMWF TIMING AND PRECIP WAS
THE BASIS FOR THIS FORECAST. NEW 06Z GFS RUN NOW IS MORE IN
LINE...EVEN THOUGH ITS LOW IS STILL FARTHER EAST THAN THE OTHER
MODELS...IT NOW HAS RAIN AS FAR NORTH AS THE CT/RI/MA BORDER BY
MON EVENING. HAVE INCREASED POPS TO 60 PERCENT NORTHWEST AND
90 PERCENT SOUTHEAST.
IN GENERAL...0.5 INCHES OF RAIN IS EXPECTED IN MANY AREAS. HOWEVER...
THE COMBINATION OF STRONG MOIST ESE FLOW AT 925 MB OVERRUNNING
LESSER NE FLOW AT THE SURFACE WILL LEAD TO THE POTENTIAL FOR LOCALLY
HEAVY SHOWERS BETWEEN MIDNIGHT AND NOON TUESDAY. BEST CHANCE IS
ALONG EASTERN MA COAST. GFS SHOWS MORE THAN 2 INCHES OF RAIN OVER
THE OPEN WATERS...THIS WILL NEED TO BE WATCHED IN CASE HEAVY RAIN
OCCURS OVER THE COASTAL AREAS.
DESPITE PERSISTENT ONSHORE FLOW MONDAY/TUESDAY...ASTRONOMICAL TIDES
ARE LOW AND THE SYSTEM DOES NOT APPEAR INTENSE ENOUGH TO RESULT IN
ANY COASTAL FLOODING. HOWEVER...MINOR BEACH EROSION CERTAINLY IS
POSSIBLE.
STUCK WITH PREVIOUS FORECAST HIGH TEMPERATURES SINCE THEY WERE
SIGNIFICANTLY COOLER THAN GFS GUIDANCE. CONFIDENCE IS HIGH THAT IT
WILL BE COOL AND RAW DURING THE AFTERNOON WITH THE ONSHORE FLOW.
TUESDAY NIGHT AND WEDNESDAY...
LOW PULLS OUT TO THE EAST AND WEAK HIGH PRESSURE MOVES IN.
THE PROBLEM IS THAT THERE WILL STILL BE ABUNDANT LOW LEVEL MOISTURE.
925 MB RELATIVE HUMIDITY REACHES 90-100 PERCENT WED AFTERNOON.
HAVE GONE WITH CLOUDY FORECAST. REDUCED CHANCE OF SHOWERS TO 20 TO 30
PERCENT IN NW HALF OF AREA BECAUSE GFS SHOWED A WEAK VORTICITY MAX
MOVING THROUGH IN THE FAST SW FLOW ALOFT. SHOULD BE LIGHT IF ANYTHING
DUE TO DRYING AIR ALOFT. HIGHS SHOULD MAINLY BE FROM 50 TO 55.
WEDNESDAY NIGHT THROUGH THANKSGIVING...
MORE OF THE SAME... GENERALLY MOSTLY CLOUDY SKIES DUE TO LOW LEVEL
MOISTURE AS FLOW REMAINS EASTERLY BEHIND DEPARTING WEAK HIGH PRESSURE
AND AHEAD OF DEVELOPING LOW PRESSURE OFF THE CAROLINA COAST. HAVE LOW
PROBABILITIES OF SHOWERS... BUT IT MAY TURN OUT TO BE MORE OF A
CHANCE OF DRIZZLE ACROSS THE AREA. LOWS MID 30S TO LOWER 40S AND
HIGHS IN THE 50S.
THURSDAY NIGHT THROUGH FRIDAY NIGHT...
A VIGOROUS UPPER LEVEL TROUGH DEVELOPING FROM THE GREAT LAKES TO THE
OHIO VALLEY WILL INTENSIFY THE CAROLINA LOW PRESSURE SYSTEM AS IT
MOVES NORTHWARD UP THE EAST COAST. 00Z GFS DEEPENS IT TO 973 MB OVER
NEW ENGLAND COMPLETE WITH LOTS OF THUNDER ETC. 06Z GFS CONTINUES THIS
FORECAST WITH 974 MB. THESE WERE CONSIDERED TOO DEEP AS ECMWF REMAINS
CONSISTENT WITH 998 MB WHICH IS WEAKER THAN ITS PREVIOUS RUN OF 993
MB. THE PLACEMENT OF THIS STORM WILL DETERMINE WHERE THE HEAVIEST
RAIN WOULD FALL. RIGHT NOW...WE HAVE ADDED 50 TO 60 PERCENT POPS TO
THE FORECAST FROM LATE THU NIGHT THROUGH FRIDAY...DIMINISHING
SOMEWHAT FRI NIGHT. IT SHOULD BE NOTED THAT THE CANADIAN GGEM MODEL
IS DRY THROUGHOUT FRIDAY. THUS AT THIS TIME...CONFIDENCE IS ONLY MEDIUM
THAT A STORM WILL FORM...AND EVEN LOWER AS TO ITS PLACEMENT.
SATURDAY... BLUSTERY AND CHILLY WEATHER LOOKS TO BE FILTERED INTO
THE REGION BEHIND THE SYSTEM. WITH THE UPPER LOW PRESSURE DIRECTLY
OVERHEAD...EXPECT RATHER UNSTABLE CONDITIONS WHICH COULD LEAD TO A
FEW RAIN SHOWERS IN THE SOUTH AND EAST AND SNOW SHOWERS IN THE
NORTHWEST...ESPECIALLY IN THE HIGHER TERRAIN. IT WILL BE TOO WARM AT THE
SURFACE FOR ANY ACCUMULATION. HIGHS ARE FORECAST TO BE IN THE UPPER
30S NORTHWEST TO MID 40 SOUTHEAST.
&&
.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
TODAY...VFR. MAY SEE PATCHY VFR TO LOCAL MVFR CIGS ALONG THE COAST
DURING THE LATE MORNING AND AFTERNOON.
TONIGHT...VFR MOST LOCATIONS. WILL LIKELY SEE MVFR CIGS MOVING IN
ALONG THE COAST S AND E OF A LINE FROM KBOS-KPVD...MAINLY NEAR OR
AFTER MIDNIGHT. WILL ALSO SEE E-NE WINDS INCREASE ACROSS CAPE COD
AND THE ISLANDS.
MONDAY...EXPECT VFR CIGS MAINLY N OF ROUTE 2 ACROSS N MA...WHILE
CONDITIONS LOWER TO MVFR-IFR CIGS S OF THERE. LOCAL IFR CIGS ALONG
THE S COAST...CAPE COD AND THE ISLANDS DURING THE AFTERNOON. PATCHY
RAIN WILL APPROACH N CT/RI/SE MA DURING THE AFTERNOON WITH LOCAL
MVFR VSBYS.
OUTLOOK /MONDAY NIGHT THROUGH FRIDAY/...
MONDAY NIGHT AND TUESDAY...IFR CONDITIONS IN LOW CLOUDS... RAIN AND
FOG. LOCALLY HEAVIER SHOWERS MAINLY EASTERN SECTIONS.
TUE NIGHT THROUGH THU...MVFR-IFR CONDITIONS MAY LINGER IN LOW
CLOUDS THROUGH THIS PERIOD. ONLY SLIGHT CHANCE OF A RAIN SHOWER BUT
MAY HAVE AREAS OF DRIZZLE AND FOG DEVELOPING...ESPECIALLY WED NIGHT.
THU NIGHT AND FRI... LOW TO MEDIUM CONFIDENCE OF IFR CEILINGS AND
VSBYS IN SHOWERS.
&&
.MARINE...
TODAY...NE WINDS WILL GRADUALLY INCREASE DURING THE DAY. WITH THE
INCREASING WIND AND ONSHORE FETCH...EXPECT SEAS TO BUILD UP TO 5 FT
MAINLY ON THE EASTERN OUTER WATERS. HAVE CONTINUED SMALL CRAFT
ADVISORY.
TONIGHT...AS LOW PRES WORKS UP THE COAST...WILL SEE E-NE WINDS
CONTINUE TO INCREASE. EXPECT WIND GUSTS UP TO 25 KT...MAINLY ON THE
SOUTHERN WATERS. SEAS WILL CONTINUE TO BUILD ON MOST OF THE
WATERS...SO HAVE PUT UP SMALL CRAFTS LATE TONIGHT FOR THE S SOUNDS.
MONDAY...E-NE WIND GUSTS UP TO 30 KT ON THE OUTER WATERS. SEAS
CONTINUE TO BUILD...POSSIBLY UP TO 8 FT WELL OFFSHORE.
OUTLOOK /MONDAY NIGHT THROUGH THURSDAY/...
MONDAY NIGHT THROUGH EARLY WEDNESDAY...LOW PRESSURE PASSING FROM
SOUTH OF NANTUCKET TO NOVA SCOTIA WILL CREATE A PERSISTENT NORTHEAST
FLOW AND GOOD GRADIENT. THIS WILL RESULT IN SCA ACROSS MOST OF OUR
WATERS OVER THIS TIME PERIOD. SEAS MAY BUILD TO BETWEEN 7 AND 12 FEET
ACROSS THE OUTER WATERS. THERE IS A LOW PROBABILITY OF BRIEF
MARGINAL GALE FORCE GUSTS MAINLY VERY LATE MON NIGHT OR ON TUESDAY
OVER THE SOUTHERN WATERS.
WEDNESDAY THROUGH THANKSGIVING...WINDS WILL CONTINUE FROM A
PERSISTENT EASTERLY DIRECTION PERHAPS BECOMING SOUTHEAST LATER THU.
THIS WILL LIKELY CAUSE SEAS TO REMAIN ABOVE SCA THRESHOLDS ACROSS THE
OUTER-WATERS. WINDS AND SEAS MAY ONCE AGAIN INCREASE VERY LATE
THANKSGIVING NIGHT IN ADVANCE OF THE NEXT SYSTEM APPROACHING FROM THE
SOUTH.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 5 AM TO 5 PM EST MONDAY FOR
ANZ232>235-237.
SMALL CRAFT ADVISORY FROM NOON TODAY TO 5 PM EST MONDAY FOR
ANZ250-254>256.
&&
$$
SYNOPSIS...EVT/GAF
NEAR TERM...EVT/GAF
SHORT TERM...EVT/GAF
LONG TERM...GAF
AVIATION...EVT/GAF
MARINE...EVT/GAF
000
FXUS61 KOKX 221137
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
637 AM EST SUN NOV 22 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER THE NORTHEASTERN UNITED STATES AND
THE CANADIAN MARITIME PROVINCES THROUGH MONDAY...THE SLIDE EAST
INTO MIDWEEK. MEANWHILE AN AREA OF LOW PRESSURE WILL MOVE FROM THE
GULF COAST TO THE SOUTHEAST COAST TODAY AND MONDAY. THE LOW TRACKS
ALONG THE SEABOARD THROUGH TUESDAY...REACHING THE CANADIAN
MARITIMES WEDNESDAY. WEAK HIGH PRESSURE BUILDS DOWN FROM THE
NORTH WEDNESDAY...BEFORE RETREATING TO THE EAST WEDNESDAY NIGHT AS
A COMPLEX STORM SYSTEM APPROACHES FROM THE WEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RIDGE REMAINS OVER THE AREA THROUGH TODAY AS SURFACE HIGH BUILDS
ACROSS SOUTHEASTERN CANADA. WINDS SHIFT FROM THE NORTH TO THE
NORTHEAST IN RESPONSE TO THE HIGH. AREA OF STRATO CU JUST TO THE
NORTH OF THE LOWER HUDSON VALLEY AND INTO NORTHEASTERN
PENNSYLVANIA NOT MAKING ANY PROGRESS TO THE SOUTH...AND WILL
LIKELY REMAIN NORTH OF THE AREA. DESPITE SUNSHINE...EASTERLY FLOW
WILL KEEP TEMPERATURES IN THE LOWER TO MID 50S ACROSS THE REGION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
UPPER RIDGE MOVES EAST TONIGHT WITH SURFACE HIGH OVER THE CANADIAN
MARITIMES. SURFACE LOW SHIFTS TO THE SOUTHEAST COAST. CLOUDS BEGIN
TO MOVE IN FROM THE SOUTH AS THE LOW DEEPENS AND TRACKS NORTH.
WITH THAT...AND NORTHEASTERLY FLOW...TEMPERATURES ALONG THE COAST
NOT EXPECTED TO FALL OFF TOO MUCH...AND INLAND TEMPERATURES TO
FALL OFF UNDER MOSTLY CLEAR SKIES...SO WILL BE LARGE CONTRAST.
MONDAY PRECIPITATION FROM THE COASTAL LOW MOVES IN FROM SOUTH TO
NORTH. GOOD AGREEMENT WITH BRINGING LIGHT RAIN INTO THE AREA
MONDAY MORNING INTO THE AFTERNOON. BEST CHANCES WILL BE MONDAY
NIGHT INTO TUESDAY AS BEST ISENTROPIC LIFT MOVES INTO THE AREA.
HAVE RAISED POPS TO LIKELY. TUESDAY BEST LIFT STARTS TO SHIFT EAST
AND LOWER POPS TUESDAY INTO TUESDAY NIGHT. GFS A LITTLE FASTER AND
DEEPER WITH THE SURFACE LOW TUESDAY INTO TUESDAY NIGHT AND LEANED
TOWARD THE SREF AND NAM. HEAVIEST PRECIPITATION LIKELY ACROSS
SOUTHEASTERN CONNECTICUT AND INTO LONG ISLAND WITH AREA OF BEST LIFT.
WITH CLOUD COVER...PRECIPITATION...AND EASTERLY WINDS WILL NOT SEE
A LARGE RANGE IN LOWS AND HIGHS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
RIDGING BUILDS BRIEFLY BETWEEN SYSTEMS WEDNESDAY...WITH LOW
DEPARTING TO THE EAST AND NEXT SYSTEM APPROACHING FROM THE WEST.
HAVE DECIDED TO KEEP SLIGHT CHANCE POPS TUESDAY NIGHT WITH SOME
UNCERTAINTY AS TO TIMING OF LOWS.
SOUTHWEST FLOW ALOFT DEVELOPS WEDNESDAY AS H5 LOW DROPS INTO THE OHIO
VALLEY. H3 JET PRODUCES SOME LIFT...BUT FORCING OTHERWISE IS WEAK
AS EVIDENCED BY THE TIME HEIGHTS. WITH MARGINAL MOISTURE...ONLY
LIGHT PRECIPITATION EXPECTED AT THIS TIME. FOCUS SHIFTS TO LATE
THURSDAY AND FRIDAY. ANOTHER H5 LOW DROPS INTO THE OHIO VALLEY
WITH A COMPLEX REFLECTION AT THE SURFACE. MODELS HINT AT LOW
PRESSURE DEVELOPING ALONG THE NORTHERN GULF COAST AND TRACKING
NORTHEASTWARD OFF THE ATLANTIC COAST...WITH A SECOND LOW
DEVELOPING OVER THE EASTERN GREAT LAKES. ALL THOUGH THERE IS A
SPREAD IN THE MODEL SOLUTIONS...IT APPEARS A SHOT OF RA ON TRACK
DURING THE PERIOD. MAIN ISSUE MAY TURN OUT TO BE THE WIND IF THE
12Z GFS/ECMWF SOLUTIONS ARE CLOSE AND A 980 MB LOW OCCLUDES OVER
NORTHERN NEW ENGLAND SATURDAY MORNING.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
VFR. SKC WITH INCREASING HIGH CLOUDS LATE IN THE DAY. PERSISTENT
NE FLOW WILL RESULT IN DEVELOPMENT OF MVFR CEILINGS
OVERNIGHT...WITH ISOLATED IFR (MAINLY AT EASTERN TERMINALS AND KSWF).
LIGHT AND VARIABLE WINDS BECOME NE 5-10 KT THIS MORNING...WITH
DIRECTION VARYING FROM 030-070 THROUGH TONIGHT.
OUTLOOK 12Z MONDAY THROUGH THURSDAY...
MONDAY...SUB-VFR POSSIBLE.
MONDAY NIGHT-TUESDAY...SUB-VFR.
TUESDAY NIGHT...BECOMING VFR.
WEDNESDAY...VFR.
WEDNESDAY NIGHT-THURSDAY...SUB-VFR POSSIBLE.
&&
.MARINE...
EXPECT CONDITIONS ON THE WATERS TO REMAIN BELOW SCA CONDITIONS ON
THE WATERS...THOUGH COULD SEE SOME OCCASIONAL GUSTS TO 25 KT LATE
THIS AFTERNOON ACROSS THE COASTAL OCEAN WATERS AS THE PRESSURE
GRADIENT BEGINS TO TIGHTEN (STRONGEST FURTHER S FROM LONG ISLAND
(FURTHEST FROM CENTER OF HIGH).
EXPECT GUSTS TO 25-30 KT ALL WATERS TONIGHT AND MONDAY IN RESPONSE
TO CONTINUED TIGHTENING PRESSURE GRADIENT BETWEEN HIGH WEDGED INTO
THE NORTHEASTERN US AND LOW PRESSURE APPROACHING FROM THE S. SEAS ON
THE OCEAN ZONES WILL BUILD TO 4 TO 8 FT BY MONDAY AS A RESULT OF
STRENGTHENING NE FLOW.
DEPENDING ON EXACT TRACK/STRENGTH OF COASTAL LOW THERE IS THE
POTENTIAL FOR GUSTS TO GALE FORCE OVER THE EASTERN TWO COASTAL OCEAN
ZONES (AND POSSIBLY A LARGER AREA)...NOT CONFIDENT ENOUGH TO GO WITH
GALE WATCH...BUT AM CONFIDENT ENOUGH TO MENTION OCCASIONAL GUSTS TO
35 KT AND EXTEND SCA ON COASTAL OCEAN WATERS THROUGH MONDAY NIGHT
(STILL ENOUGH UNCERTAINTY ON LOW TRACK/STRENGTH THAT NOT AS
CONFIDENT OF SCA CONDITIONS OVER THE SOUND/HARBOR/BAYS MONDAY NIGHT).
THE STRONG NE WINDS (POSSIBLY WITH GUSTS TO GALE FORCE OVER EASTERN
TWO COASTAL OCEAN ZONES (AND A CHANCE FOR EVEN GREATER COVERAGE)
WILL CONTINUE INTO TUESDAY...THEN SLOWLY DIMINISH TUE NIGHT AS LOW
PULLS AWAY TO THE NE. WHILE WINDS SHOULD FALL BELOW SCA LEVELS ON
ALL WATERS TUE NIGHT...THE SEAS OVER THE COASTAL OCEAN ZONES WILL
NOT. THESE SEAS LIKELY WILL REMAIN AT OR ABOVE SCA LEVELS INTO
THURSDAY.
WINDS SHOULD STAY BELOW SCA LEVELS WEDNESDAY-THURSDAY WITH REGION IN
BETWEEN POTENTIAL STRONG COASTAL STORMS.
&&
.HYDROLOGY...
DRY THROUGH MONDAY MORNING. A HALF INCH...NORTH AND WEST...TO ONE
INCH...SOUTHEAST...IS POSSIBLE FROM MONDAY AFTERNOON THROUGH
WEDNESDAY. ADDITIONAL PRECIPITATION IS POSSIBLE THURSDAY AND FRIDAY.
NO HYDROLOGIC PROBLEMS ARE ANTICIPATED.
&&
.TIDES/COASTAL FLOODING...
CURRENT COASTAL FLOODING GUIDANCE WOULD NOT SUGGEST ANY FLOOD
THREAT...HOWEVER IT IS BASED ON THE MODEL THAT IS FURTHEST OUT TO
SEA AND MOST PROGRESSIVE WITH THE COASTAL STORM MONDAY-WEDNESDAY. IF
STORM TAKES THE CURRENT CONSENSUS IDEA OF A TRACK THAT IS CLOSER TO
THE COAST AND SLOWER THAN THE MODEL USED TO MAKE THE STORM SURGE
FORECAST...WOULD SEE LARGER DEPARTURES THAN NORMAL THAN GUIDANCE
CURRENTLY SUGGESTS. FOR MINOR COASTAL FLOODING MONDAY-TUESDAY YOU
WOULD NEED DEPARTURES OF 2-2.5 FT ABOVE NORMAL FOR THE HIGHER OF THE
TWO HIGH TIDES AND 2.5-3 FT ABOVE NORMAL FOR THE LOWER OF THE TWO
HIGH TIDES. CURRENT GUIDANCE ONLY SUGGESTS DEPARTURES OF 0.5-1
FT...SO EVEN A SLOWER/CLOSER TO THE COAST SCENARIO MAY MOT PRODUCE
LARGE ENOUGH DEPARTURES TO CAUSE COASTAL FLOODING. THIS WILL
CONTINUE TO BE MONITORED CLOSELY.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 5 PM EST MONDAY
FOR ANZ330-335-338-340-345.
SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EST
TUESDAY FOR ANZ350-353-355.
&&
$$
SYNOPSIS AND NEAR/SHORT TERM...MET
LONG TERM...JMC
AVIATION/MARINE...MALOIT
HYDROLOGY...MET
TIDES/COASTAL FLOODING...MALOIT
000
FXUS61 KALY 221128
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
623 AM EST SUN NOV 22 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL COVER THE NORTHEAST TO START THE
WEEK. IT WILL SLIDE EAST INTO THE MARITIMES AND OFFSHORE LATE MONDAY.
OUR WEATHER WILL TURN UNSETTLED MUCH OF THE UPCOMING WEEK. THE FIRST
LOW PRESSURE AREA WILL MOVE NORTHEAST FROM THE CAROLINA COAST
OFFSHORE MONDAY NIGHT AND TUESDAY. THEN MIDWEEK A SERIES OF MUCH
STRONGER STORMS WILL MOVE THOUGH THE MIDWEST AND GREAT LAKES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MOISTURE TRAPPED BENEATH LOW LEVEL SUBSIDENCE INVERSION WILL KEEP
PATCHY LOW CLOUDS AROUND THROUGH AT LEAST LATE THIS MORNING. IN
FACT...WHERE SOME BREAKS HAVE DEVELOPED...CLOUDS MAY ACTUALLY
REDEVELOP AROUND OR JUST AFTER SUNRISE ONCE SHALLOW MIXING
DEVELOPS. EVENTUALLY...AS THE LOW LEVEL FLOW VEERS INTO A MORE NE
DIRECTION...SOME DOWNSLOPING OFF THE HIGHER TERRAIN TO OUR N/E
SHOULD ALLOW FOR MORE BREAKS IN THE CLOUDS TO DEVELOP THIS
AFTERNOON...ESP FROM THE HUDSON RIVER VALLEY EASTWARD. CLOUDS MAY
PERSIST LONGER...PERHAPS WELL INTO THE AFTERNOON...ACROSS WESTERN
PORTIONS OF THE REGION...FROM THE SW DACKS...WESTERN MOHAWK VALLEY
INTO THE SCHOHARIE VALLEY AND NE CATSKILLS.
AS FOR MAX TEMPS...GIVEN THE EXPECTATION FOR SHALLOW MIXING...MAINLY
TO 925-950 MB...WE EXPECT MAXES TO BE A BIT COOLER THAN SAT...ESP
GIVEN A SLIGHTLY COLDER START...ALONG WITH THE EXPECTATION FOR
CLOUDS THROUGH THE MORNING. SO...GENERALLY SIDED CLOSE TO THE COOLER
MET MOS...WITH MAXES GENERALLY REACHING AROUND 50 WITHIN MUCH OF THE
HUDSON RIVER VALLEY...EXCEPT LOWER/MID 50S ACROSS THE MID HUDSON
VALLEY...WITH MAINLY 40S ACROSS HIGHER ELEVATIONS WITHIN WESTERN NEW
ENGLAND AND WESTERN PORTIONS OF THE REGION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
PERIOD STARTS WITH RIDGING AND SUBSIDENCE THROUGHOUT THE
ATMOSPHERE WITH 572DM HIGH EVEN AT 500HPA. 500HPA TROF LINGERS
SOUTH OF RGN FM MASON DIXON LINE TO LONG IS NY WHILE IMPRESSIVE
SFC HIGH DOMINATES THE NORTHEAST QUARTER OF THE NATION AND IS
CENTERED OVER THE MARITIMES. WHILE THE DIRTY HIGH PHASE WITH
MOISTURE TRAPPED UNDER THE INVERSION WILL HAVE ENDED EARLY SUNDAY
THE NEW GUIDANCE SUGGESTS THE MOIST BOUNDARY LAYER REMAINS AND
SHOWS MARINE LAYER MOISTURE OR FOG/STRATUS CREEPING BACK UP THE
HUDSON VALLEY EVEN AS EARLY AS LATE SUNDAY NIGHT EARLY MONDAY
MORNING. THE WITH ALL THE MODELS AND STATISTICAL GUID KEEPING THE
FLOW EAST TO NORTHEAST BELOW THE INVERSION LAYER...WILL BRING
CLOUDS INTO THE SOUTHEAST. THE NAM IS THE ONLY LESS AGGRESSIVE
MODEL WITH ADVECTING THIS MARINE LAYER MOISTURE WHILE THE
WRF/GEM/GFS SHOW IT BLO 900HPA.
MUCH LIKE LAST WEEK WHEN THIS SAME SCENARIO OCCURRED CLOUDS SHOULD
BARELY MAKE ALBANY MONDAY MORNING AND THESE MAY ERODE FOR A TIME.
FROM ALB N & W WILL STAY FAIR A GOOD PART OF THE DAY TILL BOUNDARY
LEVEL FLOW TURNS SE-S AND MOISTURE STREAMS NORTH. IN SOUTHEAST
LOOKING AT AREAS OF MORNING STRATUS AND FOG THAT MAY OR MAY NOT
BURN OFF BEFORE THE CLOUDS FROM NEXT SYSTEM OVERSPREAD THOSE
AREAS.
MARINE LAYER MOISTURE ADVECTION SHOULD BE WEAK TILL 500HPA TROF
THAT WAS LAYING DORMANT ACROSS THE MID ATLC BEGINS MOVES NORTH
INTO OUR REGION MONDAY. MODELS SUGGEST A COASTAL DEVELOPMENT BUT
ITS WELL OFFSHORE AND ITS MAIN IMPACT IS TO ENHANCE THE MARINE
LAYER INFLOW. THIS MOISTURE AND THE PASSAGE OF SEVERAL 500HPA
SHORT WAVES WILL PRODUCE CLOUDS ACROSS THE AREA AND AN INCR CHC
OF -RN AND DZ MONDAY NIGHT AND TUES MAINLY IN THE SOUTHEAST.
INITIALLY TUESDAY NIGHT THE SFC LOW DEPARTS WELL OFFSHORE. 500HPA
RIDGE REBUILDS ALONG THE SEABOARD. WELL TO OUR WEST THE STAGE IS
BEING SET FOR A COMPLEX PATTERN TO END THE WEEK. TUES NT WERE
STUCK WITH MORE RESIDUAL LOW LEVEL MOISTURE AND NOT MUCH MORE THAN
DRIZZLE AND CLOUDS.
MEANWHILE TUESDAY NIGHT TWO CUTOFFS WILL BE SETTING UP. ONE IN
THE MISSISSIPPI VALLEY THE OTHER IN SOUTH CENTRAL CANADA. LOOKING
AT THE 1.5PVU SFCS THE ORIGINS OF THESE SYSTEMS ARE THREE
PART. 1) JUST OFF THE BRITISH COLUMBIA ALASKA PANHANDLE
COAST...2) IN THE FAST FLOW IN THE CENTRAL PACIFIC NORTH OF
HAWAII AND 3) ALONG ALASKA`S BROOKS RANGE. OBVIOUSLY MANY
QUESTIONS REMAIN ABOUT THE PHASING PROCESS AND THE RESULTANT SFC
WEATHER. MORE IN THIS IN LONG TERM SECTION.
THROUGH TUESDAY NIGHT THERES A FAIR AMOUNT OF MODEL CONSISTENCY
EXCEPT WITH REGARD TO THE MAGNITUDE OF THE MARINE LAYER INFLOW
MONDAY AS DISCUSSED ABOVE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE LONG RANGE FORECAST PERIOD IS THE RESULT OF THE ORGANIZATION OF
TWO MAJOR CUT OFFS AND THEIR INTERACTION AND EVENTUAL MERGER. GIVEN
THE LOCATIONS OF THE VORTICITY THAT WILL GIVE RISE TO THIS SCENARIO
(GIVEN AT END OF SHORT TERM)...MUCH REMAINS UNCERTAIN AND SUBJECT
TO CHANGE BASED ON THE PHASING TIME...DEGREE...LOCATION AND THEN THE
ULTIMATE SFC RESPONSE.
THERE ARE SOME GENERAL THEMES IN MOST OF THE GUIDANCE. ONE CUT
OFF OVER THE MID WEST LIFTS NORTHEAST INTO THE RIDGE OVER THE
EASTERN SEABOARD WEDNESDAY. THE SECOND DIVES SOUTH OUT OF CENTRAL
CANADA. THEY DUMBBELL AROUND EACH OTHER AND MERGE BY THEN END OF
THE WEEK. HWVR POSITIONS RANGE FM CENTERED N OF YUL (GEM)..TO NJ
(GFS) TO OHIO (ECMWF).
WHAT IS MOST CONCRETE AT THIS POINT IS WEDNESDAY THE FIRST 500HPA
CUT OFF MOVES FM MIDWEST INTO GRT LAKES AND PUSHES AN OCCLUDED
FRONT INTO NYS LATE IN THE DAY. THE GFS/GEM AND ECMWF SHOW THIS
SCENARIO WITH THAT CANADIAN ABOUT 6 HOURS FASTER WITH PCPN. WILL
KEEP IT DRY IN THE MORNING WITH CHC POPS AFTN AND WED NIGHT.
THE TIMING ISSUES BECOME MORE ACUTE FROM THURSDAY ON. THURSDAY
THE GFS PUTS FCA IN DRY SLOT AHEAD OF NEXT FRONTAL SYSTEM PUSHING
ACROSS FCA. THE GEM/ECM BRING THE NEXT FRONTAL SYSTEM THROUGH.
IN SUMMARY THE LONG RANGE PERIOD GENERAL THEMES ARE FAIRLY
CLEAR...BUT TIMING IS ALL OVER. OTHER THAN WED WILL LEAVE MUCH OF
THE EARLIER HPC BASED LONG RANGE IN PLACE WITH JUST SOME TWEAKS TO
IMPROVE COORDINATION. TO CHANGE IT TO GMOS AT THIS TIME WILL JUST
INCREASE THE FLIP FLOP FACTOR.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
MVFR LEVEL CLOUDS HAVE REDEVELOPED AT KGFL AND KALB. WE EXPECT THESE
CLOUDS TO PERSIST UNTIL AROUND 15Z...BEFORE GRADUALLY
LIFTING/ERODING. THERE IS A SMALL CHANCE OF IFR LEVEL CLOUDS TO
DEVELOP BENEATH THIS DECK...ESP AT KGFL...PRIOR TO 15Z...AND HAVE
INDICATED A TEMPO AT KGFL DUE TO THIS POSSIBILITY. CONDITIONS SHOULD
IMPROVE TO VFR AFTER 15Z...WITH VFR CONDITIONS PERSISTING THROUGH AT
LEAST MIDNIGHT TONIGHT. THEREAFTER...A LOW STRATUS DECK MAY ADVECT
NORTHWARD...UP THE HUDSON RIVER VALLEY...AFTER 08Z/MON. WE HAVE
INDICATED MVFR CONDITIONS...MAINLY FOR CIGS...TO DEVELOP FROM S TO N
TOWARD DAYBREAK. SOME IFR CIGS ARE POSSIBLE AT KPOU...BUT CONFIDENCE
LOW ENOUGH AT THIS TIME RANGE TO KEEP LOW MVFR AT KPOU.
WINDS WILL REMAIN LIGHT...MAINLY FROM THE NE TO E AT 5-10 KT TODAY.
WINDS WILL THEN BECOME LIGHT/VARIABLE TONIGHT.
OUTLOOK...
MON-TUE...VFR-MVFR...CHC OF RAIN MON NT-TUE.
WED...VFR...CHC OF SHOWERS.
THU...MVFR/IFR...RAIN POSSIBLE LATE.
&&
.HYDROLOGY...
WITH DRY CONDITIONS EXPECTED TO LAST AT LEAST INTO MONDAY RIVERS
WILL CONTINUE RECEDE THROUGH MONDAY. THE NEXT THREAT OF RAIN WILL
BE LATE MONDAY INTO TUESDAY. CONSENSUS OF MODELS IS FOR 0.10 TO
0.30 INCHES MAINLY IN THE SOUTHEAST. THIS EVENT SHOULD HAVE MODEST
IMPACT ON RIVERS AND STREAMS. FURTHER OUT AN UNSETTLED PERIOD OF
WEATHER THURSDAY INTO THE WEEKEND COULD RESULT IN SIGNIFICANT
PRECIPITATION AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SNYDER
NEAR TERM...KL
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...KL
HYDROLOGY...SNYDER
000
FXUS61 KBOX 221052
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
552 AM EST SUN NOV 22 2009
.SYNOPSIS...
HIGH PRESSURE EXTENDING FROM NEW YORK STATE INTO QUEBEC WILL MOVE
ACROSS NORTHERN NEW ENGLAND INTO THE MARITIMES TONIGHT...THEN EAST
OF NOVA SCOTIA MONDAY. LOW PRESSURE WILL BRING RAIN TO THE REGION
LATE MONDAY INTO TUESDAY. WEAK HIGH PRESSURE WILL TEMPORARILY BUILD
INTO THE REGION TUESDAY NIGHT INTO WEDNESDAY NIGHT THEN MOVE OFFSHORE
THANKSGIVING DAY. ANOTHER LOW PRESSURE SYSTEM WILL MOVE UP THE COAST
LATE THURSDAY AND FRIDAY BRINGING A CHANCE OF MORE RAIN. COLDER
BLUSTERY WEATHER IS FORECAST FOR SATURDAY BEHIND THAT DEPARTING LOW.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SKIES WERE GENERALLY CLEAR ACROSS THE REGION EARLY THIS MORNING...
EXCEPT FOR LOCALIZED LOW CLOUDS AND FOG ACROSS A FEW OF THE NORMALLY
SUSCEPTIBLE VALLEY AREAS. CAN ALSO SEE LOW CLOUDS EXTENDING FROM S
VT INTO THE BERKSHIRES AND ALL ACROSS NY STATE/PA ON THE SATELLITE
FOG PRODUCT. ONCE THE SUN RISES...NOT EXPECTING THESE CLOUDS TO
STICK AROUND TOO LONG...EVEN WITH LOW SUN ANGLE.
HIGH PRES ACROSS NY STATE INTO EASTERN CANADA WILL SLOWLY MOVE NE
TODAY. THIS WILL INSURE MOSTLY CLEAR SKIES FOR MOST AREAS. SOME OF
THE MODELS...ESPECIALLY THE CANADIAN REGIONAL GEM...HAS BEEN HINTING
AT LOW CLOUDS DEVELOPING OFFSHORE AND MOVING IN ALONG THE COAST. THE
RGEM TENDS TO HANDLE CLOUDS WELL. ALSO NOTED HIGH RH VALUES AND LOW
CLOUDS ON THE NAM BUFKIT CROSS SECTIONS FOR THIS AFTERNOON ALONG THE
COAST. HAVE ADDED ONLY PARTLY CLOUDY SKIES ACROSS SE MA...CAPE COD
AND THE ISLANDS FOR NOW.
AS LIGHT WINDS VEER AROUND TO N-NE...WILL SEE DAYTIME HIGHS ON THE
COOLER SIDE TODAY ESPECIALLY ALONG THE COAST. FORECASTING HIGHS
MAINLY IN THE LOWER-MID 50S...WHICH CONTINUED TO RUN UP TO 5 DEGREES
OR SO ABOVE NORMAL.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
TONIGHT...HIGH PRESSURE WILL CONTINUE TO SHIFT NE ACROSS NOVA
SCOTIA. THIS...ALONG WITH LOW PRES DEVELOPING OFF THE MID ATLC COAST
WILL CAUSE A TIGHTENING PRES GRADIENT...SLOWLY INCREASING THE E-NE
WIND ESPECIALLY ALONG THE COAST. RGEM CONTINUES TO PUSH LOW CLOUDS
AND FOG INTO COASTAL AREAS...AND EVEN FURTHER INLAND. HOWEVER...WITH
THE DEVELOPING LOW PRES OFF THE MID ATLC...WILL ALSO START TO SEE
MOISTURE WORK UP THE COAST AS WELL. HAVE FORECASTED INCREASING
CLOUDS THROUGH THE NIGHT ACROSS CENTRAL AND SOUTHERN AREAS.
OVERNIGHT LOWS WILL FALL BACK TO THE 30S TO AROUND 40...THOUGH MOS
GUIDANCE MAY BE A BIT TOO COLD CONSIDERING THE INCREASING CLOUDS AND
ONSHORE WIND...MAINLY S OF THE MASS PIKE.
MONDAY...CONDITIONS WILL DETERIORATE DURING THE DAY AS THE LOW
STARTS TO SLOWLY WORK NE. MODELS TRY TO BRING PRECIP INTO THE REGION
DURING THE DAY...WITH THE CANADIAN GEM MODELS BEING THE MOST
AGGRESSIVE. WITH THE STRONG HIGH TO THE N...FEEL THE DRY AIRMASS
OVER THE REGION WILL HOLD THE PRECIP OFF THROUGH AT LEAST MIDDAY...
AND PROBABLY NOT UNTIL NIGHTFALL OR AFTER ACROSS N MA/S NH. HAVE
BROUGHT CHANCE POPS INTO SOUTHERN AREAS DURING THE AFTERNOON AS THE
AIRMASS MOISTENS UP WITH THE ONSHORE FLOW AS WELL AS THE PRECIP
WORKING UP THE COAST.
WITH THE ONSHORE FLOW CONTINUING TO INCREASE AND THE APPROACHING
PRECIP...EXPECT DAYTIME HIGHS ONLY IN THE UPPER 40S TO MID 50S...
BUT THIS WILL STILL BE UP TO 5 DEGREES ABOVE SEASONAL NORMS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MONDAY NIGHT AND TUESDAY...
MODELS NOW ALL IN LINE WITH LOW PRESSURE MOVING FROM SOUTH OF
NANTUCKET MONDAY EVENING TO NEAR NOVA SCOTIA LATE TUESDAY NIGHT.
RAIN WILL MOVE ACROSS THE REGION FROM SOUTH TO NORTH MONDAY EVENING.
RGEM IS FASTEST OF 00Z MODELS RUNS WITH PRECIP IN RI AND CT BEFORE
7 PM MON. 00Z GFS WAS CONSIDERED OUTLIER WITH THE LOW TOO FAR OFF
THE COAST AND LITTLE RAINFALL OVER LAND. ECMWF TIMING AND PRECIP WAS
THE BASIS FOR THIS FORECAST. NEW 06Z GFS RUN NOW IS MORE IN
LINE...EVEN THOUGH ITS LOW IS STILL FARTHER EAST THAN THE OTHER
MODELS...IT NOW HAS RAIN AS FAR NORTH AS THE CT/RI/MA BORDER BY
MON EVENING. HAVE INCREASED POPS TO 60 PERCENT NORTHWEST AND
90 PERCENT SOUTHEAST.
IN GENERAL...0.5 INCHES OF RAIN IS EXPECTED IN MANY AREAS. HOWEVER...
THE COMBINATION OF STRONG MOIST ESE FLOW AT 925 MB OVERRUNNING
LESSER NE FLOW AT THE SURFACE WILL LEAD TO THE POTENTIAL FOR LOCALLY
HEAVY SHOWERS BETWEEN MIDNIGHT AND NOON TUESDAY. BEST CHANCE IS
ALONG EASTERN MA COAST. GFS SHOWS MORE THAN 2 INCHES OF RAIN OVER
THE OPEN WATERS...THIS WILL NEED TO BE WATCHED IN CASE HEAVY RAIN
OCCURS OVER THE COASTAL AREAS.
DESPITE PERSISTENT ONSHORE FLOW MONDAY/TUESDAY...ASTRONOMICAL TIDES
ARE LOW AND THE SYSTEM DOES NOT APPEAR INTENSE ENOUGH TO RESULT IN
ANY COASTAL FLOODING. HOWEVER...MINOR BEACH EROSION CERTAINLY IS
POSSIBLE.
STUCK WITH PREVIOUS FORECAST HIGH TEMPERATURES SINCE THEY WERE
SIGNIFICANTLY COOLER THAN GFS GUIDANCE. CONFIDENCE IS HIGH THAT IT
WILL BE COOL AND RAW DURING THE AFTERNOON WITH THE ONSHORE FLOW.
TUESDAY NIGHT AND WEDNESDAY...
LOW PULLS OUT TO THE EAST AND WEAK HIGH PRESSURE MOVES IN.
THE PROBLEM IS THAT THERE WILL STILL BE ABUNDANT LOW LEVEL MOISTURE.
925 MB RELATIVE HUMIDITY REACHES 90-100 PERCENT WED AFTERNOON.
HAVE GONE WITH CLOUDY FORECAST. REDUCED CHANCE OF SHOWERS TO 20 TO 30
PERCENT IN NW HALF OF AREA BECAUSE GFS SHOWED A WEAK VORTICITY MAX
MOVING THROUGH IN THE FAST SW FLOW ALOFT. SHOULD BE LIGHT IF ANYTHING
DUE TO DRYING AIR ALOFT. HIGHS SHOULD MAINLY BE FROM 50 TO 55.
WEDNESDAY NIGHT THROUGH THANKSGIVING...
MORE OF THE SAME... GENERALLY MOSTLY CLOUDY SKIES DUE TO LOW LEVEL
MOISTURE AS FLOW REMAINS EASTERLY BEHIND DEPARTING WEAK HIGH PRESSURE
AND AHEAD OF DEVELOPING LOW PRESSURE OFF THE CAROLINA COAST. HAVE LOW
PROBABILITIES OF SHOWERS... BUT IT MAY TURN OUT TO BE MORE OF A
CHANCE OF DRIZZLE ACROSS THE AREA. LOWS MID 30S TO LOWER 40S AND
HIGHS IN THE 50S.
THURSDAY NIGHT THROUGH FRIDAY NIGHT...
A VIGOROUS UPPER LEVEL TROUGH DEVELOPING FROM THE GREAT LAKES TO THE
OHIO VALLEY WILL INTENSIFY THE CAROLINA LOW PRESSURE SYSTEM AS IT
MOVES NORTHWARD UP THE EAST COAST. 00Z GFS DEEPENS IT TO 973 MB OVER
NEW ENGLAND COMPLETE WITH LOTS OF THUNDER ETC. 06Z GFS CONTINUES THIS
FORECAST WITH 974 MB. THESE WERE CONSIDERED TOO DEEP AS ECMWF REMAINS
CONSISTENT WITH 998 MB WHICH IS WEAKER THAN ITS PREVIOUS RUN OF 993
MB. THE PLACEMENT OF THIS STORM WILL DETERMINE WHERE THE HEAVIEST
RAIN WOULD FALL. RIGHT NOW...WE HAVE ADDED 50 TO 60 PERCENT POPS TO
THE FORECAST FROM LATE THU NIGHT THROUGH FRIDAY...DIMINISHING
SOMEWHAT FRI NIGHT. IT SHOULD BE NOTED THAT THE CANADIAN GGEM MODEL
IS DRY THROUGHOUT FRIDAY. THUS AT THIS TIME...CONFIDENCE IS ONLY MEDIUM
THAT A STORM WILL FORM...AND EVEN LOWER AS TO ITS PLACEMENT.
SATURDAY... BLUSTERY AND CHILLY WEATHER LOOKS TO BE FILTERED INTO
THE REGION BEHIND THE SYSTEM. WITH THE UPPER LOW PRESSURE DIRECTLY
OVERHEAD...EXPECT RATHER UNSTABLE CONDITIONS WHICH COULD LEAD TO A
FEW RAIN SHOWERS IN THE SOUTH AND EAST AND SNOW SHOWERS IN THE
NORTHWEST...ESPECIALLY IN THE HIGHER TERRAIN. IT WILL BE TOO WARM AT THE
SURFACE FOR ANY ACCUMULATION. HIGHS ARE FORECAST TO BE IN THE UPPER
30S NORTHWEST TO MID 40 SOUTHEAST.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
TODAY...VFR. MAY SEE PATCHY VFR TO LOCAL MVFR CIGS ALONG THE COAST
DURING THE LATE MORNING AND AFTERNOON.
TONIGHT...VFR MOST LOCATIONS. WILL LIKELY SEE MVFR CIGS MOVING IN
ALONG THE COAST S AND E OF A LINE FROM KBOS-KPVD...MAINLY NEAR OR
AFTER MIDNIGHT. WILL ALSO SEE E-NE WINDS INCREASE ACROSS CAPE COD
AND THE ISLANDS.
MONDAY...EXPECT VFR CIGS MAINLY N OF ROUTE 2 ACROSS N MA...WHILE
CONDITIONS LOWER TO MVFR-IFR CIGS S OF THERE. LOCAL IFR CIGS ALONG
THE S COAST...CAPE COD AND THE ISLANDS DURING THE AFTERNOON. PATCHY
RAIN WILL APPROACH N CT/RI/SE MA DURING THE AFTERNOON WITH LOCAL
MVFR VSBYS.
OUTLOOK /MONDAY NIGHT THROUGH FRIDAY/...
MONDAY NIGHT AND TUESDAY...IFR CONDITIONS IN LOW CLOUDS... RAIN AND
FOG. LOCALLY HEAVIER SHOWERS MAINLY EASTERN SECTIONS.
TUE NIGHT THROUGH THU...MVFR-IFR CONDITIONS MAY LINGER IN LOW
CLOUDS THROUGH THIS PERIOD. ONLY SLIGHT CHANCE OF A RAIN SHOWER BUT
MAY HAVE AREAS OF DRIZZLE AND FOG DEVELOPING...ESPECIALLY WED NIGHT.
THU NIGHT AND FRI... LOW TO MEDIUM CONFIDENCE OF IFR CEILINGS AND
VSBYS IN SHOWERS.
&&
.MARINE...
TODAY...NE WINDS WILL GRADUALLY INCREASE DURING THE DAY. WITH THE
INCREASING WIND AND ONSHORE FETCH...EXPECT SEAS TO BUILD UP TO 5 FT
MAINLY ON THE EASTERN OUTER WATERS. HAVE CONTINUED SMALL CRAFT
ADVISORY.
TONIGHT...AS LOW PRES WORKS UP THE COAST...WILL SEE E-NE WINDS
CONTINUE TO INCREASE. EXPECT WIND GUSTS UP TO 25 KT...MAINLY ON THE
SOUTHERN WATERS. SEAS WILL CONTINUE TO BUILD ON MOST OF THE
WATERS...SO HAVE PUT UP SMALL CRAFTS LATE TONIGHT FOR THE S SOUNDS.
MONDAY...E-NE WIND GUSTS UP TO 30 KT ON THE OUTER WATERS. SEAS
CONTINUE TO BUILD...POSSIBLY UP TO 8 FT WELL OFFSHORE.
OUTLOOK /MONDAY NIGHT THROUGH THURSDAY/...
MONDAY NIGHT THROUGH EARLY WEDNESDAY...LOW PRESSURE PASSING FROM
SOUTH OF NANTUCKET TO NOVA SCOTIA WILL CREATE A PERSISTENT NORTHEAST
FLOW AND GOOD GRADIENT. THIS WILL RESULT IN SCA ACROSS MOST OF OUR
WATERS OVER THIS TIME PERIOD. SEAS MAY BUILD TO BETWEEN 7 AND 12 FEET
ACROSS THE OUTER WATERS. THERE IS A LOW PROBABILITY OF BRIEF
MARGINAL GALE FORCE GUSTS MAINLY VERY LATE MON NIGHT OR ON TUESDAY
OVER THE SOUTHERN WATERS.
WEDNESDAY THROUGH THANKSGIVING...WINDS WILL CONTINUE FROM A
PERSISTENT EASTERLY DIRECTION PERHAPS BECOMING SOUTHEAST LATER THU.
THIS WILL LIKELY CAUSE SEAS TO REMAIN ABOVE SCA THRESHOLDS ACROSS THE
OUTER-WATERS. WINDS AND SEAS MAY ONCE AGAIN INCREASE VERY LATE
THANKSGIVING NIGHT IN ADVANCE OF THE NEXT SYSTEM APPROACHING FROM THE
SOUTH.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 5 AM TO 5 PM EST MONDAY FOR
ANZ232>235-237.
SMALL CRAFT ADVISORY FROM NOON TODAY TO 5 PM EST MONDAY FOR
ANZ250-254>256.
&&
$$
SYNOPSIS...EVT/GAF
NEAR TERM...EVT
SHORT TERM...EVT
LONG TERM...GAF
AVIATION...EVT/GAF
MARINE...EVT/GAF
000
FXUS61 KOKX 221026
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
526 AM EST SUN NOV 22 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER THE NORTHEASTERN UNITED STATES AND
THE CANADIAN MARITIME PROVINCES THROUGH MONDAY...THE SLIDE EAST
INTO MIDWEEK. MEANWHILE AN AREA OF LOW PRESSURE WILL MOVE FROM THE
GULF COAST TO THE SOUTHEAST COAST TODAY AND MONDAY. THE LOW TRACKS
ALONG THE SEABOARD THROUGH TUESDAY...REACHING THE CANADIAN
MARITIMES WEDNESDAY. WEAK HIGH PRESSURE BUILDS DOWN FROM THE
NORTH WEDNESDAY...BEFORE RETREATING TO THE EAST WEDNESDAY NIGHT AS
A COMPLEX STORM SYSTEM APPROACHES FROM THE WEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RIDGE REMAINS OVER THE AREA THROUGH TODAY AS SURFACE HIGH BUILDS
ACROSS SOUTHEASTERN CANADA. WINDS SHIFT FROM THE NORTH TO THE
NORTHEAST IN RESPONSE TO THE HIGH. AREA OF STRATO CU JUST TO THE
NORTH OF THE LOWER HUDSON VALLEY AND INTO NORTHEASTERN
PENNSYLVANIA NOT MAKING ANY PROGRESS TO THE SOUTH...AND WILL
LIKELY REMAIN NORTH OF THE AREA. DESPITE SUNSHINE...EASTERLY FLOW
WILL KEEP TEMPERATURES IN THE LOWER TO MID 50S ACROSS THE REGION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
UPPER RIDGE MOVES EAST TONIGHT WITH SURFACE HIGH OVER THE CANADIAN
MARITIMES. SURFACE LOW SHIFTS TO THE SOUTHEAST COAST. CLOUDS BEGIN
TO MOVE IN FROM THE SOUTH AS THE LOW DEEPENS AND TRACKS NORTH.
WITH THAT...AND NORTHEASTERLY FLOW...TEMPERATURES ALONG THE COAST
NOT EXPECTED TO FALL OFF TOO MUCH...AND INLAND TEMPERATURES TO
FALL OFF UNDER MOSTLY CLEAR SKIES...SO WILL BE LARGE CONTRAST.
MONDAY PRECIPITATION FROM THE COASTAL LOW MOVES IN FROM SOUTH TO
NORTH. GOOD AGREEMENT WITH BRINGING LIGHT RAIN INTO THE AREA
MONDAY MORNING INTO THE AFTERNOON. BEST CHANCES WILL BE MONDAY
NIGHT INTO TUESDAY AS BEST ISENTROPIC LIFT MOVES INTO THE AREA.
HAVE RAISED POPS TO LIKELY. TUESDAY BEST LIFT STARTS TO SHIFT EAST
AND LOWER POPS TUESDAY INTO TUESDAY NIGHT. GFS A LITTLE FASTER AND
DEEPER WITH THE SURFACE LOW TUESDAY INTO TUESDAY NIGHT AND LEANED
TOWARD THE SREF AND NAM. HEAVIEST PRECIPITATION LIKELY ACROSS
SOUTHEASTERN CONNECTICUT AND INTO LONG ISLAND WITH AREA OF BEST LIFT.
WITH CLOUD COVER...PRECIPITATION...AND EASTERLY WINDS WILL NOT SEE
A LARGE RANGE IN LOWS AND HIGHS.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
RIDGING BUILDS BRIEFLY BETWEEN SYSTEMS WEDNESDAY...WITH LOW
DEPARTING TO THE EAST AND NEXT SYSTEM APPROACHING FROM THE WEST.
HAVE DECIDED TO KEEP SLIGHT CHANCE POPS TUESDAY NIGHT WITH SOME
UNCERTAINTY AS TO TIMING OF LOWS.
SOUTHWEST FLOW ALOFT DEVELOPS WEDNESDAY AS H5 LOW DROPS INTO THE OHIO
VALLEY. H3 JET PRODUCES SOME LIFT...BUT FORCING OTHERWISE IS WEAK
AS EVIDENCED BY THE TIME HEIGHTS. WITH MARGINAL MOISTURE...ONLY
LIGHT PRECIPITATION EXPECTED AT THIS TIME. FOCUS SHIFTS TO LATE
THURSDAY AND FRIDAY. ANOTHER H5 LOW DROPS INTO THE OHIO VALLEY
WITH A COMPLEX REFLECTION AT THE SURFACE. MODELS HINT AT LOW
PRESSURE DEVELOPING ALONG THE NORTHERN GULF COAST AND TRACKING
NORTHEASTWARD OFF THE ATLANTIC COAST...WITH A SECOND LOW
DEVELOPING OVER THE EASTERN GREAT LAKES. ALL THOUGH THERE IS A
SPREAD IN THE MODEL SOLUTIONS...IT APPEARS A SHOT OF RA ON TRACK
DURING THE PERIOD. MAIN ISSUE MAY TURN OUT TO BE THE WIND IF THE
12Z GFS/ECMWF SOLUTIONS ARE CLOSE AND A 980 MB LOW OCCLUDES OVER
NORTHERN NEW ENGLAND SATURDAY MORNING.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
VFR TODAY WITH NORTHERLY WINDS 5 TO 10 KT EARLY THIS MORNING WILL
VEER NORTHEAST DURING THE DAY TIME AS HIGH PRESSURE SETTLES OVER
SOUTHEASTERN CANADA.
THERE IS A DECENT CHANCE FOR MVFR CEILINGS/VISIBILITIES TONIGHT IN
NORTHEAST FLOW.
OUTLOOK 06Z MONDAY THROUGH THURSDAY...
SUNDAY NIGHT...POSSIBLE SUB VFR.
MONDAY...SUB-VFR POSSIBLE.
MONDAY NIGHT-TUESDAY...SUB-VFR LIKELY.
TUESDAY NIGHT...BECOMING VFR.
WEDNESDAY...VFR.
WEDNESDAY NIGHT-THURSDAY...SUB-VFR POSSIBLE.
&&
.MARINE...
EXPECT CONDITIONS ON THE WATERS TO REMAIN BELOW SCA CONDITIONS ON
THE WATERS...THOUGH COULD SEE SOME OCCASIONAL GUSTS TO 25 KT LATE
THIS AFTERNOON ACROSS THE COASTAL OCEAN WATERS AS THE PRESSURE
GRADIENT BEGINS TO TIGHTEN (STRONGEST FURTHER S FROM LONG ISLAND
(FURTHEST FROM CENTER OF HIGH).
EXPECT GUSTS TO 25-30 KT ALL WATERS TONIGHT AND MONDAY IN RESPONSE
TO CONTINUED TIGHTENING PRESSURE GRADIENT BETWEEN HIGH WEDGED INTO
THE NORTHEASTERN US AND LOW PRESSURE APPROACHING FROM THE S. SEAS ON
THE OCEAN ZONES WILL BUILD TO 4 TO 8 FT BY MONDAY AS A RESULT OF
STRENGTHENING NE FLOW.
DEPENDING ON EXACT TRACK/STRENGTH OF COASTAL LOW THERE IS THE
POTENTIAL FOR GUSTS TO GALE FORCE OVER THE EASTERN TWO COASTAL OCEAN
ZONES (AND POSSIBLY A LARGER AREA)...NOT CONFIDENT ENOUGH TO GO WITH
GALE WATCH...BUT AM CONFIDENT ENOUGH TO MENTION OCCASIONAL GUSTS TO
35 KT AND EXTEND SCA ON COASTAL OCEAN WATERS THROUGH MONDAY NIGHT
(STILL ENOUGH UNCERTAINTY ON LOW TRACK/STRENGTH THAT NOT AS
CONFIDENT OF SCA CONDITIONS OVER THE SOUND/HARBOR/BAYS MONDAY NIGHT).
THE STRONG NE WINDS (POSSIBLY WITH GUSTS TO GALE FORCE OVER EASTERN
TWO COASTAL OCEAN ZONES (AND A CHANCE FOR EVEN GREATER COVERAGE)
WILL CONTINUE INTO TUESDAY...THEN SLOWLY DIMINISH TUE NIGHT AS LOW
PULLS AWAY TO THE NE. WHILE WINDS SHOULD FALL BELOW SCA LEVELS ON
ALL WATERS TUE NIGHT...THE SEAS OVER THE COASTAL OCEAN ZONES WILL
NOT. THESE SEAS LIKELY WILL REMAIN AT OR ABOVE SCA LEVELS INTO
THURSDAY.
WINDS SHOULD STAY BELOW SCA LEVELS WEDNESDAY-THURSDAY WITH REGION IN
BETWEEN POTENTIAL STRONG COASTAL STORMS.
&&
.HYDROLOGY...
DRY THROUGH MONDAY MORNING. A HALF INCH...NORTH AND WEST...TO ONE
INCH...SOUTHEAST...IS POSSIBLE FROM MONDAY AFTERNOON THROUGH
WEDNESDAY. ADDITIONAL PRECIPITATION IS POSSIBLE THURSDAY AND FRIDAY.
NO HYDROLOGIC PROBLEMS ARE ANTICIPATED.
&&
.TIDES/COASTAL FLOODING...
CURRENT COASTAL FLOODING GUIDANCE WOULD NOT SUGGEST ANY FLOOD
THREAT...HOWEVER IT IS BASED ON THE MODEL THAT IS FURTHEST OUT TO
SEA AND MOST PROGRESSIVE WITH THE COASTAL STORM MONDAY-WEDNESDAY. IF
STORM TAKES THE CURRENT CONSENSUS IDEA OF A TRACK THAT IS CLOSER TO
THE COAST AND SLOWER THAN THE MODEL USED TO MAKE THE STORM SURGE
FORECAST...WOULD SEE LARGER DEPARTURES THAN NORMAL THAN GUIDANCE
CURRENTLY SUGGESTS. FOR MINOR COASTAL FLOODING MONDAY-TUESDAY YOU
WOULD NEED DEPARTURES OF 2-2.5 FT ABOVE NORMAL FOR THE HIGHER OF THE
TWO HIGH TIDES AND 2.5-3 FT ABOVE NORMAL FOR THE LOWER OF THE TWO
HIGH TIDES. CURRENT GUIDANCE ONLY SUGGESTS DEPARTURES OF 0.5-1
FT...SO EVEN A SLOWER/CLOSER TO THE COAST SCENARIO MAY MOT PRODUCE
LARGE ENOUGH DEPARTURES TO CAUSE COASTAL FLOODING. THIS WILL
CONTINUE TO BE MONITORED CLOSELY.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 5 PM EST MONDAY
FOR ANZ330-335-338-340-345.
SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EST
TUESDAY FOR ANZ350-353-355.
&&
$$
SYNOPSIS...MET
NEAR TERM...MET
SHORT TERM...MET
LONG TERM...
AVIATION...PFM
MARINE...PFM
HYDROLOGY...MET
TIDES/COASTAL FLOODING...PFM
000
FXUS61 KBOX 221013
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
510 AM EST SUN NOV 22 2009
.SYNOPSIS...
HIGH PRESSURE EXTENDING FROM NEW YORK STATE INTO QUEBEC WILL MOVE
ACROSS NORTHERN NEW ENGLAND INTO THE MARITIMES TONIGHT...THEN EAST
OF NOVA SCOTIA MONDAY. LOW PRESSURE WILL BRING RAIN TO THE REGION
LATE MONDAY INTO TUESDAY. WEAK HIGH PRESSURE WILL TEMPORARILY BUILD
INTO THE REGION WEDNESDAY NIGHT AND THANKSGIVING DAY...BEFORE
ANOTHER LOW PRESSURE THREATENS THE REGION WITH MORE RAIN VERY LATE
THANKSGIVING NIGHT AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SKIES WERE GENERALLY CLEAR ACROSS THE REGION EARLY THIS MORNING...
EXCEPT FOR LOCALIZED LOW CLOUDS AND FOG ACROSS A FEW OF THE NORMALLY
SUSCEPTIBLE VALLEY AREAS. CAN ALSO SEE LOW CLOUDS EXTENDING FROM S
VT INTO THE BERKSHIRES AND ALL ACROSS NY STATE/PA ON THE SATELLITE
FOG PRODUCT. ONCE THE SUN RISES...NOT EXPECTING THESE CLOUDS TO
STICK AROUND TOO LONG...EVEN WITH LOW SUN ANGLE.
HIGH PRES ACROSS NY STATE INTO EASTERN CANADA WILL SLOWLY MOVE NE
TODAY. THIS WILL INSURE MOSTLY CLEAR SKIES FOR MOST AREAS. SOME OF
THE MODELS...ESPECIALLY THE CANADIAN REGIONAL GEM...HAS BEEN HINTING
AT LOW CLOUDS DEVELOPING OFFSHORE AND MOVING IN ALONG THE COAST. THE
RGEM TENDS TO HANDLE CLOUDS WELL. ALSO NOTED HIGH RH VALUES AND LOW
CLOUDS ON THE NAM BUFKIT CROSS SECTIONS FOR THIS AFTERNOON ALONG THE
COAST. HAVE ADDED ONLY PARTLY CLOUDY SKIES ACROSS SE MA...CAPE COD
AND THE ISLANDS FOR NOW.
AS LIGHT WINDS VEER AROUND TO N-NE...WILL SEE DAYTIME HIGHS ON THE
COOLER SIDE TODAY ESPECIALLY ALONG THE COAST. FORECASTING HIGHS
MAINLY IN THE LOWER-MID 50S...WHICH CONTINUED TO RUN UP TO 5 DEGREES
OR SO ABOVE NORMAL.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
TONIGHT...HIGH PRESSURE WILL CONTINUE TO SHIFT NE ACROSS NOVA
SCOTIA. THIS...ALONG WITH LOW PRES DEVELOPING OFF THE MID ATLC COAST
WILL CAUSE A TIGHTENING PRES GRADIENT...SLOWLY INCREASING THE E-NE
WIND ESPECIALLY ALONG THE COAST. RGEM CONTINUES TO PUSH LOW CLOUDS
AND FOG INTO COASTAL AREAS...AND EVEN FURTHER INLAND. HOWEVER...WITH
THE DEVELOPING LOW PRES OFF THE MID ATLC...WILL ALSO START TO SEE
MOISTURE WORK UP THE COAST AS WELL. HAVE FORECASTED INCREASING
CLOUDS THROUGH THE NIGHT ACROSS CENTRAL AND SOUTHERN AREAS.
OVERNIGHT LOWS WILL FALL BACK TO THE 30S TO AROUND 40...THOUGH MOS
GUIDANCE MAY BE A BIT TOO COLD CONSIDERING THE INCREASING CLOUDS AND
ONSHORE WIND...MAINLY S OF THE MASS PIKE.
MONDAY...CONDITIONS WILL DETERIORATE DURING THE DAY AS THE LOW
STARTS TO SLOWLY WORK NE. MODELS TRY TO BRING PRECIP INTO THE REGION
DURING THE DAY...WITH THE CANADIAN GEM MODELS BEING THE MOST
AGGRESSIVE. WITH THE STRONG HIGH TO THE N...FEEL THE DRY AIRMASS
OVER THE REGION WILL HOLD THE PRECIP OFF THROUGH AT LEAST MIDDAY...
AND PROBABLY NOT UNTIL NIGHTFALL OR AFTER ACROSS N MA/S NH. HAVE
BROUGHT CHANCE POPS INTO SOUTHERN AREAS DURING THE AFTERNOON AS THE
AIRMASS MOISTENS UP WITH THE ONSHORE FLOW AS WELL AS THE PRECIP
WORKING UP THE COAST.
WITH THE ONSHORE FLOW CONTINUING TO INCREASE AND THE APPROACHING
PRECIP...EXPECT DAYTIME HIGHS ONLY IN THE UPPER 40S TO MID 50S...
BUT THIS WILL STILL BE UP TO 5 DEGREES ABOVE SEASONAL NORMS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MONDAY NIGHT AND TUESDAY...
CONFIDENCE IS INCREASING THAT AT LEAST SOME RAIN WILL AFFECT THE
REGION LATER MONDAY INTO TUESDAY. THE MAIN DILEMMA IS HOW CLOSE TO
THE COAST A WAVE OF LOW PRESSURE TRACKS AND ALSO ITS INTENSITY.
HOWEVER...LATEST MODELS ALONG WITH SREF ENSEMBLES SUGGEST THAT EVEN
IF THE SOUTHERN AND WEAKEST SOLUTIONS VERIFY THERE WILL LIKELY BE AT
LEAST SOME RAIN WITH PERSISTENT ONSHORE FLOW.
THE MAIN QUESTION IS WILL A PERIOD OF HEAVIER RAIN EFFECT PORTIONS
OF THE REGION. THE GEM/NAM CERTAINLY SHOW THIS POTENTIAL...WHILE
THE GFS/UKMET ARE MUCH FURTHER SOUTH SUGGESTING MAINLY
RAIN/DRIZZLE. THE ECMWF IS NOT AS EXTREME AS THE VERY WET GEM/NAM
BUT IT DOES LEAN IN MORE OF THEIR DIRECTION. THEREFORE...WE WILL
LEAN IN THE ECMWF/S DIRECTION FOR NOW ESPECIALLY CONSIDERING ITS
TRACK RECORD IN THIS TIMEFRAME. WILL RUN WITH A PERIOD OF LIKELY
POPS ACROSS THE ENTIRE REGION MONDAY NIGHT/TUESDAY. A PERIOD OF
HEAVY RAIN IS POSSIBLE DEPENDING ON HOW CLOSE TO THE COAST THE WAVE
OF LOW PRESSURE TRACKS. THE BEST CHANCE FOR HEAVY RAIN WILL BE
ACROSS THE SOUTHERN AND EASTERN SECTIONS. IN FACT...LATER SHIFTS
MAY HAVE TO INCREASE POPS INTO CATEGORICAL LEVELS FOR SOME OF THE
REGION.
DESPITE PERSISTENT ONSHORE FLOW MONDAY/TUESDAY...ASTRONOMICAL TIDES
ARE LOW AND THE SYSTEM DOES NOT APPEAR INTENSE ENOUGH TO RESULT IN
ANY COASTAL FLOODING. HOWEVER...MINOR BEACH EROSION CERTAINLY IS
POSSIBLE.
AS FOR TEMPERATURES...CONFIDENCE IS HIGH THAT IT WILL BE RATHER COOL
AND RAW DURING THE AFTERNOON. HIGHS MAINLY IN THE UPPER 40S AND THE
LOWER 50S WITH THE ONSHORE FLOW. CONFIDENCE IS ALSO HIGH THAT WHAT
EVER FALLS WILL BE IN THE LIQUID VARIETY. LOW TEMPERATURES SHOULD
REMAIN IN THE 40 TO 45 DEGREE RANGE ACROSS MOST OF THE REGION.
WEDNESDAY...
LOW CONFIDENCE FORECAST OVER THIS TIME...BUT THE STEADIEST
PRECIPITATION WILL LIKELY BE OVER. HOWEVER...WILL CONTINUE WITH THE
CHANCE OF A FEW SHOWERS WITH WAVE OF LOW PRESSURE STILL SPINNING OFF
THE COAST. PRECIPITATION CHANCES MAY DIMINISH LATER WEDNESDAY
AFTERNOON AND EVENING AS DRIER AIR WORKS INTO THE REGION FROM THE
WEST AND THE LOW FINALLY PULLS AWAY. HIGHS SHOULD MAINLY BE IN THE
UPPER 40S TO MID 50S ACROSS THE REGION.
WEDNESDAY NIGHT THROUGH FRIDAY...
ALTHOUGH THE TIMING CAN CERTAINLY CHANGE SINCE WE ARE STILL 5 TO 6
DAYS OUT...AT THIS TIME IT APPEARS THAT MOST OF WEDNESDAY NIGHT
THANKSGIVING DAY MAY TURN OUT DRY. A WEAK RIDGE OF HIGH PRESSURE
LOOKS TO TEMPORARILY BUILD INTO THE REGION WEDNESDAY NIGHT AND
THANKSGIVING DAY.
HOWEVER...A VIGOROUS TROUGH DEVELOPING OVER THE GREAT LAKES MAY
ALLOW ANOTHER LOW PRESSURE SYSTEM TO AFFECT THE REGION LATE
THANKSGIVING NIGHT INTO FRIDAY. AGAIN...TIMING AND FORECASTS ARE
SUBJECT TO SIGNIFICANT ERRORS THIS FAR IN ADVANCE. HOWEVER...THIS
MAY BRING MORE RAIN TO THE REGION. TEMPERATURE PROFILES CONTINUE TO
LOOK TOO WARM SUPPORT ANY FROZEN PRECIPITATION EVEN IN THE DISTANT
INTERIOR FOR MOST OF THE POTENTIAL EVENT.
SATURDAY...
BLUSTERY AND CHILLY WEATHER LOOKS TO BE FILTERED INTO THE REGION
BEHIND THE SYSTEM. MUCH OF THE DAY WILL BE DRY...BUT CAN NOT RULE
OUT A FEW SPRINKLES/PASSING RAIN SHOWER SO WILL RUN WITH A SLIGHT
CHANCE. ITS NOT OUT OF THE QUESTION THAT A FEW WET SNOWFLAKES FALL
ACROSS THE INTERIOR HIGH TERRAIN BUT IT DOES NOT APPEAR TO BE A BIG
DEAL.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
TODAY...VFR. MAY SEE PATCHY VFR TO LOCAL MVFR CIGS ALONG THE COAST
DURING THE LATE MORNING AND AFTERNOON.
TONIGHT...VFR MOST LOCATIONS. WILL LIKELY SEE MVFR CIGS MOVING IN
ALONG THE COAST S AND E OF A LINE FROM KBOS-KPVD...MAINLY NEAR OR
AFTER MIDNIGHT. WILL ALSO SEE E-NE WINDS INCREASE ACROSS CAPE COD
AND THE ISLANDS.
MONDAY...EXPECT VFR CIGS MAINLY N OF ROUTE 2 ACROSS N MA...WHILE
CONDITIONS LOWER TO MVFR-IFR CIGS S OF THERE. LOCAL IFR CIGS ALONG
THE S COAST...CAPE COD AND THE ISLANDS DURING THE AFTERNOON. PATCHY
RAIN WILL APPROACH N CT/RI/SE MA DURING THE AFTERNOON WITH LOCAL
MVFR VSBYS.
OUTLOOK /MONDAY NIGHT THROUGH THURSDAY/...
MONDAY NIGHT AND TUESDAY...MVFR-IFR CONDITIONS IN LOW CLOUDS AND
RAIN WILL OVERSPREAD THE REGION FROM SOUTH TO NORTH.
WEDNESDAY...LOW CONFIDENCE FORECAST BUT MVFR-IFR CONDITIONS MAY
LINGER IN LOW CLOUDS/RAIN SHOWERS FOR A TIME.
WEDNESDAY NIGHT AND THANKSGIVING...MAINLY VFR BUT CONDITIONS MAY
DETERIORATE LATE THANKSGIVING NIGHT.
&&
.MARINE...
TODAY...NE WINDS WILL GRADUALLY INCREASE DURING THE DAY. WITH THE
INCREASING WIND AND ONSHORE FETCH...EXPECT SEAS TO BUILD UP TO 5 FT
MAINLY ON THE EASTERN OUTER WATERS. HAVE CONTINUED SMALL CRAFT
ADVISORY.
TONIGHT...AS LOW PRES WORKS UP THE COAST...WILL SEE E-NE WINDS
CONTINUE TO INCREASE. EXPECT WIND GUSTS UP TO 25 KT...MAINLY ON THE
SOUTHERN WATERS. SEAS WILL CONTINUE TO BUILD ON MOST OF THE
WATERS...SO HAVE PUT UP SMALL CRAFTS LATE TONIGHT FOR THE S SOUNDS.
MONDAY...E-NE WIND GUSTS UP TO 30 KT ON THE OUTER WATERS. SEAS
CONTINUE TO BUILD...POSSIBLY UP TO 8 FT WELL OFFSHORE.
OUTLOOK /MONDAY NIGHT THROUGH THURSDAY/...
MONDAY THROUGH WEDNESDAY...CANADIAN HIGH PRESSURE WITH LOW PRESSURE
TO THE SOUTH WILL CREATE A PERSISTENT NORTHEAST FLOW AND GOOD
GRADIENT. THIS WILL RESULT IN SCA ACROSS MOST OF OUR WATERS OVER
THIS TIME. SEAS MAY BUILD TO BETWEEN 7 AND 12 FEET ACROSS THE
OUTER-WATERS. THERE IS A LOW PROBABILITY OF A BRIEF MARGINAL GALE
AT SOME POINT.
THANKSGIVING...WINDS SHOULD TEMPORARILY DIMINISH AS WEAK RIDGE OF
HIGH PRESSURE BUILDS IN DURING THE DAY. HOWEVER...SEAS WILL LIKELY
REMAIN ABOVE SCA THRESHOLDS ACROSS THE OUTER-WATERS. WINDS AND SEAS
MAY ONCE AGAIN INCREASE VERY LATE THANKSGIVING NIGHT IN ADVANCE OF
OUR NEXT POSSIBLE SYSTEM
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 5 AM TO 5 PM EST MONDAY FOR
ANZ232>235-237.
SMALL CRAFT ADVISORY FROM NOON TODAY TO 5 PM EST MONDAY FOR
ANZ250-254>256.
&&
$$
SYNOPSIS...FRANK/EVT
NEAR TERM...FRANK/EVT
SHORT TERM...EVT
LONG TERM...FRANK
AVIATION...FRANK/EVT
MARINE...FRANK/EVT
000
FXUS61 KALY 220825
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
325 AM EST SUN NOV 22 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL COVER THE NORTHEAST TO START THE
WEEK. IT WILL SLIDE EAST INTO THE MARITIMES AND OFFSHORE LATE MONDAY.
OUR WEATHER WILL TURN UNSETTLED MUCH OF THE UPCOMING WEEK. THE FIRST
LOW PRESSURE AREA WILL MOVE NORTHEAST FROM THE CAROLINA COAST
OFFSHORE MONDAY NIGHT AND TUESDAY. THEN MIDWEEK A SERIES OF MUCH
STRONGER STORMS WILL MOVE THOUGH THE MIDWEST AND GREAT LAKES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MOISTURE TRAPPED BENEATH LOW LEVEL SUBSIDENCE INVERSION WILL KEEP
PATCHY LOW CLOUDS AROUND THROUGH AT LEAST LATE THIS MORNING. IN
FACT...WHERE SOME BREAKS HAVE DEVELOPED...CLOUDS MAY ACTUALLY
REDEVELOP AROUND OR JUST AFTER SUNRISE ONCE SHALLOW MIXING
DEVELOPS. EVENTUALLY...AS THE LOW LEVEL FLOW VEERS INTO A MORE NE
DIRECTION...SOME DOWNSLOPING OFF THE HIGHER TERRAIN TO OUR N/E
SHOULD ALLOW FOR MORE BREAKS IN THE CLOUDS TO DEVELOP THIS
AFTERNOON...ESP FROM THE HUDSON RIVER VALLEY EASTWARD. CLOUDS MAY
PERSIST LONGER...PERHAPS WELL INTO THE AFTERNOON...ACROSS WESTERN
PORTIONS OF THE REGION...FROM THE SW DACKS...WESTERN MOHAWK VALLEY
INTO THE SCHOHARIE VALLEY AND NE CATSKILLS.
AS FOR MAX TEMPS...GIVEN THE EXPECTATION FOR SHALLOW MIXING...MAINLY
TO 925-950 MB...WE EXPECT MAXES TO BE A BIT COOLER THAN SAT...ESP
GIVEN A SLIGHTLY COLDER START...ALONG WITH THE EXPECTATION FOR
CLOUDS THROUGH THE MORNING. SO...GENERALLY SIDED CLOSE TO THE COOLER
MET MOS...WITH MAXES GENERALLY REACHING AROUND 50 WITHIN MUCH OF THE
HUDSON RIVER VALLEY...EXCEPT LOWER/MID 50S ACROSS THE MID HUDSON
VALLEY...WITH MAINLY 40S ACROSS HIGHER ELEVATIONS WITHIN WESTERN NEW
ENGLAND AND WESTERN PORTIONS OF THE REGION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
PERIOD STARTS WITH RIDGING AND SUBSIDENCE THROUGHOUT THE
ATMOSPHERE WITH 572DM HIGH EVEN AT 500HPA. 500HPA TROF LINGERS
SOUTH OF RGN FM MASON DIXON LINE TO LONG IS NY WHILE IMPRESSIVE
SFC HIGH DOMINATES THE NORTHEAST QUARTER OF THE NATION AND IS
CENTERED OVER THE MARITIMES. WHILE THE DIRTY HIGH PHASE WITH
MOISTURE TRAPPED UNDER THE INVERSION WILL HAVE ENDED EARLY SUNDAY
THE NEW GUIDANCE SUGGESTS THE MOIST BOUNDARY LAYER REMAINS AND
SHOWS MARINE LAYER MOISTURE OR FOG/STRATUS CREEPING BACK UP THE
HUDSON VALLEY EVEN AS EARLY AS LATE SUNDAY NIGHT EARLY MONDAY
MORNING. THE WITH ALL THE MODELS AND STATISTICAL GUID KEEPING THE
FLOW EAST TO NORTHEAST BELOW THE INVERSION LAYER...WILL BRING
CLOUDS INTO THE SOUTHEAST. THE NAM IS THE ONLY LESS AGGRESSIVE
MODEL WITH ADVECTING THIS MARINE LAYER MOISTURE WHILE THE
WRF/GEM/GFS SHOW IT BLO 900HPA.
MUCH LIKE LAST WEEK WHEN THIS SAME SCENARIO OCCURRED CLOUDS SHOULD
BARELY MAKE ALBANY MONDAY MORNING AND THESE MAY ERODE FOR A TIME.
FROM ALB N & W WILL STAY FAIR A GOOD PART OF THE DAY TILL BOUNDARY
LEVEL FLOW TURNS SE-S AND MOISTURE STREAMS NORTH. IN SOUTHEAST
LOOKING AT AREAS OF MORNING STRATUS AND FOG THAT MAY OR MAY NOT
BURN OFF BEFORE THE CLOUDS FROM NEXT SYSTEM OVERSPREAD THOSE
AREAS.
MARINE LAYER MOISTURE ADVECTION SHOULD BE WEAK TILL 500HPA TROF
THAT WAS LAYING DORMANT ACROSS THE MID ATLC BEGINS MOVES NORTH
INTO OUR REGION MONDAY. MODELS SUGGEST A COASTAL DEVELOPMENT BUT
ITS WELL OFFSHORE AND ITS MAIN IMPACT IS TO ENHANCE THE MARINE
LAYER INFLOW. THIS MOISTURE AND THE PASSAGE OF SEVERAL 500HPA
SHORT WAVES WILL PRODUCE CLOUDS ACROSS THE AREA AND AN INCR CHC
OF -RN AND DZ MONDAY NIGHT AND TUES MAINLY IN THE SOUTHEAST.
INITIALLY TUESDAY NIGHT THE SFC LOW DEPARTS WELL OFFSHORE. 500HPA
RIDGE REBUILDS ALONG THE SEABOARD. WELL TO OUR WEST THE STAGE IS
BEING SET FOR A COMPLEX PATTERN TO END THE WEEK. TUES NT WERE
STUCK WITH MORE RESIDUAL LOW LEVEL MOISTURE AND NOT MUCH MORE THAN
DRIZZLE AND CLOUDS.
MEANWHILE TUESDAY NIGHT TWO CUTOFFS WILL BE SETTING UP. ONE IN
THE MISSISSIPPI VALLEY THE OTHER IN SOUTH CENTRAL CANADA. LOOKING
AT THE 1.5PVU SFCS THE ORIGINS OF THESE SYSTEMS ARE THREE
PART. 1) JUST OFF THE BRITISH COLUMBIA ALASKA PANHANDLE
COAST...2) IN THE FAST FLOW IN THE CENTRAL PACIFIC NORTH OF
HAWAII AND 3) ALONG ALASKA`S BROOKS RANGE. OBVIOUSLY MANY
QUESTIONS REMAIN ABOUT THE PHASING PROCESS AND THE RESULTANT SFC
WEATHER. MORE IN THIS IN LONG TERM SECTION.
THROUGH TUESDAY NIGHT THERES A FAIR AMOUNT OF MODEL CONSISTENCY
EXCEPT WITH REGARD TO THE MAGNITUDE OF THE MARINE LAYER INFLOW
MONDAY AS DISCUSSED ABOVE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE LONG RANGE FORECAST PERIOD IS THE RESULT OF THE ORGANIZATION OF
TWO MAJOR CUT OFFS AND THEIR INTERACTION AND EVENTUAL MERGER. GIVEN
THE LOCATIONS OF THE VORTICITY THAT WILL GIVE RISE TO THIS SCENARIO
(GIVEN AT END OF SHORT TERM)...MUCH REMAINS UNCERTAIN AND SUBJECT
TO CHANGE BASED ON THE PHASING TIME...DEGREE...LOCATION AND THEN THE
ULTIMATE SFC RESPONSE.
THERE ARE SOME GENERAL THEMES IN MOST OF THE GUIDANCE. ONE CUT
OFF OVER THE MID WEST LIFTS NORTHEAST INTO THE RIDGE OVER THE
EASTERN SEABOARD WEDNESDAY. THE SECOND DIVES SOUTH OUT OF CENTRAL
CANADA. THEY DUMBBELL AROUND EACH OTHER AND MERGE BY THEN END OF
THE WEEK. HWVR POSITIONS RANGE FM CENTERED N OF YUL (GEM)..TO NJ
(GFS) TO OHIO (ECMWF).
WHAT IS MOST CONCRETE AT THIS POINT IS WEDNESDAY THE FIRST 500HPA
CUT OFF MOVES FM MIDWEST INTO GRT LAKES AND PUSHES AN OCCLUDED
FRONT INTO NYS LATE IN THE DAY. THE GFS/GEM AND ECMWF SHOW THIS
SCENARIO WITH THAT CANADIAN ABOUT 6 HOURS FASTER WITH PCPN. WILL
KEEP IT DRY IN THE MORNING WITH CHC POPS AFTN AND WED NIGHT.
THE TIMING ISSUES BECOME MORE ACUTE FROM THURSDAY ON. THURSDAY
THE GFS PUTS FCA IN DRY SLOT AHEAD OF NEXT FRONTAL SYSTEM PUSHING
ACROSS FCA. THE GEM/ECM BRING THE NEXT FRONTAL SYSTEM THROUGH.
IN SUMMARY THE LONG RANGE PERIOD GENERAL THEMES ARE FAIRLY
CLEAR...BUT TIMING IS ALL OVER. OTHER THAN WED WILL LEAVE MUCH OF
THE EARLIER HPC BASED LONG RANGE IN PLACE WITH JUST SOME TWEAKS TO
IMPROVE COORDINATION. TO CHANGE IT TO GMOS AT THIS TIME WILL JUST
INCREASE THE FLIP FLOP FACTOR.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE REGION THROUGH SUNDAY.
TRICKY CALL AT ALL TAF SITES THROUGH AT LEAST 12Z/SUN...AS HIGHER
STRATUS DECK AS ERODED...LEAVING SKIES MAINLY CLEAR...AND WITH
LIGHT WINDS AND A SOMEWHAT MOIST BOUNDARY LAYER...MAY PROMOTE
PATCHY FOG AND/OR LOWER CLOUDS TO DEVELOP. HOWEVER...LATEST 11-3.9
IR SATELLITE INDICATES PREVIOUS STRATUS DECK EXPANDING BACK TO THE
W...AS WINDS AROUND 925-975 MB VEER INTO THE NE. BOTTOM LINE...LOW
CONFIDENCE ON WHETHER IFR CONDITIONS DEVELOP AT THE TAF SITES OVER
THE NEXT 3-6 HOURS...HIGHLY DEPENDENT ON THE HIGHER CLOUD DECK.
FOR NOW...HAVE INDICATED SEVERAL TEMPOS FOR IFR CONDITIONS...MOST
LIKELY AROUND 12Z...ESP AT KGFL AND KALB.
AFTER 12Z/SUN...ANY IFR CONDITIONS SHOULD LIFT INTO MVFR
CIGS...WHICH COULD LAST UNTIL 15Z-17Z. THEREAFTER...EXPECT VFR
CONDITIONS FOR THIS AFTERNOON INTO THIS EVENING. ADDITIONAL
MVFR/IFR VSBYS/CIGS MAY REDEVELOP TOWARD 06Z/MON.
WINDS WILL REMAIN LIGHT...MAINLY FROM THE N TO NE AT LESS THAN 5
KT THROUGH DAYBREAK...AND NE TO E AT 5-10 KT DURING SUNDAY. WINDS
WILL THEN BECOME LIGHT/VARIABLE SUNDAY NIGHT.
OUTLOOK...
SUN NITE...VFR...NO SIG WX.
MON-TUE...VFR-MVFR...CHC OF RAIN.
WED...VFR...CHC OF SHOWERS.
THU...MVFR/IFR...RAIN POSSIBLE LATE.
&&
.HYDROLOGY...
WITH DRY CONDITIONS EXPECTED TO LAST AT LEAST INTO MONDAY RIVERS
WILL CONTINUE RECEDE THROUGH MONDAY. THE NEXT THREAT OF RAIN WILL
BE LATE MONDAY INTO TUESDAY. CONSENSUS OF MODELS IS FOR 0.10 TO
0.30 INCHES MAINLY IN THE SOUTHEAST. THIS EVENT SHOULD HAVE MODEST
IMPACT ON RIVERS AND STREAMS. FURTHER OUT AN UNSETTLED PERIOD OF
WEATHER THURSDAY INTO THE WEEKEND COULD RESULT IN SIGNIFICANT
PRECIPITATION AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SNYDER
NEAR TERM...KL
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...KL
HYDROLOGY...SNYDER
000
FXUS61 KALY 220821
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
321 AM EST SUN NOV 22 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL COVER THE NORTHEAST TO START THE
WEEK. IT WILL SLIDE EAST INTO THE MARITIMES AND OFFSHORE LATE MONDAY.
OUR WEATHER WILL TURN UNSETTLED MUCH OF THE UPCOMING WEEK. THE FIRST
LOW PRESSURE AREA WILL MOVE NORTHEAST FROM THE CAROLINA COAST
OFFSHORE MONDAY NIGHT AND TUESDAY. THEN MIDWEEK A SERIES OF MUCH
STRONGER STORMS WILL MOVE THOUGH THE MIDWEST AND GREAT LAKES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MOISTURE TRAPPED BENEATH LOW LEVEL SUBSIDENCE INVERSION WILL KEEP
PATCHY LOW CLOUDS AROUND THROUGH AT LEAST LATE THIS MORNING. IN
FACT...WHERE SOME BREAKS HAVE DEVELOPED...CLOUDS MAY ACTUALLY
REDEVELOP AROUND OR JUST AFTER SUNRISE ONCE SHALLOW MIXING
DEVELOPS. EVENTUALLY...AS THE LOW LEVEL FLOW VEERS INTO A MORE NE
DIRECTION...SOME DOWNSLOPING OFF THE HIGHER TERRAIN TO OUR N/E
SHOULD ALLOW FOR MORE BREAKS IN THE CLOUDS TO DEVELOP THIS
AFTERNOON...ESP FROM THE HUDSON RIVER VALLEY EASTWARD. CLOUDS MAY
PERSIST LONGER...PERHAPS WELL INTO THE AFTERNOON...ACROSS WESTERN
PORTIONS OF THE REGION...FROM THE SW DACKS...WESTERN MOHAWK VALLEY
INTO THE SCHOHARIE VALLEY AND NE CATSKILLS.
AS FOR MAX TEMPS...GIVEN THE EXPECTATION FOR SHALLOW MIXING...MAINLY
TO 925-950 MB...WE EXPECT MAXES TO BE A BIT COOLER THAN SAT...ESP
GIVEN A SLIGHTLY COLDER START...ALONG WITH THE EXPECTATION FOR
CLOUDS THROUGH THE MORNING. SO...GENERALLY SIDED CLOSE TO THE COOLER
MET MOS...WITH MAXES GENERALLY REACHING AROUND 50 WITHIN MUCH OF THE
HUDSON RIVER VALLEY...EXCEPT LOWER/MID 50S ACROSS THE MID HUDSON
VALLEY...WITH MAINLY 40S ACROSS HIGHER ELEVATIONS WITHIN WESTERN NEW
ENGLAND AND WESTERN PORTIONS OF THE REGION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... PERIOD
STARTS WITH RIDGING AND SUBSIDENCE THROUGHOUT THE ATMOSPHERE WITH
572DM HIGH EVEN AT 500HPA. 500HPA TROF LINGERS SOUTH OF RGN FM
MASON DIXON LINE TO LONG IS NY WHILE IMPRESSIVE SFC HIGH DOMINATES
THE NORTHEAST QUARTER OF THE NATION AND IS CENTERED OVER THE
MARITIMES. WHILE THE DIRTY HIGH PHASE WITH MOISTURE TRAPPED UNDER
THE INVERSION WILL HAVE ENDED EARLY SUNDAY THE NEW GUIDANCE
SUGGESTS THE MOIST BOUNDARY LAYER REMAINS AND SHOWS MARINE LAYER
MOISTURE OR FOG/STRATUS CREEPING BACK UP THE HUDSON VALLEY EVEN AS
EARLY AS LATE SUNDAY NIGHT EARLY MONDAY MORNING. THE WITH ALL THE
MODELS AND STATISTICAL GUID KEEPING THE FLOW EAST TO NORTHEAST
BELOW THE INVERSION LAYER...WILL BRING CLOUDS INTO THE SOUTHEAST.
THE NAM IS THE ONLY LESS AGGRESSIVE MODEL WITH ADVECTING THIS
MARINE LAYER MOISTURE WHILE THE WRF/GEM/GFS SHOW IT BLO 900HPA.
MUCH LIKE LAST WEEK WHEN THIS SAME SCENARIO OCCURRED CLOUDS SHOULD
BARELY MAKE ALBANY MONDAY MORNING AND THESE MAY ERODE FOR A TIME.
FROM ALB N & W WILL STAY FAIR A GOOD PART OF THE DAY TILL BOUNDARY
LEVEL FLOW TURNS SE-S AND MOISTURE STREAMS NORTH. IN SOUTHEAST
LOOKING AT AREAS OF MORNING STRATUS AND FOG THAT MAY OR MAY NOT
BURN OFF BEFORE THE CLOUDS FROM NEXT SYSTEM OVERSPREAD THOSE
AREAS.
MARINE LAYER MOISTURE ADVECTION SHOULD BE WEAK TILL 500HPA TROF
THAT WAS LAYING DORMANT ACROSS THE MID ATLC BEGINS MOVES NORTH
INTO OUR REGION MONDAY. MODELS SUGGEST A COASTAL DEVELOPMENT BUT
ITS WELL OFFSHORE AND ITS MAIN IMPACT IS TO ENHANCE THE MARINE
LAYER INFLOW. THIS MOISTURE AND THE PASSAGE OF SEVERAL 500HPA
SHORT WAVES WILL PRODUCE CLOUDS ACROSS THE AREA AND AN INCR CHC
OF -RN AND DZ MONDAY NIGHT AND TUES MAINLY IN THE SOUTHEAST.
INITIALLY TUESDAY NIGHT THE SFC LOW DEPARTS WELL OFFSHORE. 500HPA
RIDGE REBUILDS ALONG THE SEABOARD. WELL TO OUR WEST THE STAGE IS
BEING SET FOR A COMPLEX PATTERN TO END THE WEEK. TUES NT WERE
STUCK WITH MORE RESIDUAL LOW LEVEL MOISTURE AND NOT MUCH MORE THAN
DRIZZLE AND CLOUDS.
MEANWHILE TUESDAY NIGHT TWO CUTOFFS WILL BE SETTING UP. ONE IN
THE MISSISSIPPI VALLEY THE OTHER IN SOUTH CENTRAL CANADA. LOOKING
AT THE 1.5PVU SFCS THE ORIGINS OF THESE SYSTEMS ARE THREE
PART. 1) JUST OFF THE BRITISH COLUMBIA ALASKA PANHANDLE
COAST...2) IN THE FAST FLOW IN THE CENTRAL PACIFIC NORTH OF
HAWAII AND 3) ALONG ALASKA`S BROOKS RANGE. OBVIOUSLY MANY
QUESTIONS REMAIN ABOUT THE PHASING PROCESS AND THE RESULTANT SFC
WEATHER. MORE IN THIS IN LONG TERM SECTION.
THROUGH TUESDAY NIGHT THERES A FAIR AMOUNT OF MODEL CONSISTENCY
EXCEPT WITH REGARD TO THE MAGNITUDE OF THE MARINE LAYER INFLOW
MONDAY AS DISCUSSED ABOVE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
THE LONG RANGE FORECAST PERIOD IS THE RESULT OF THE ORGANIZATION OF
TWO MAJOR CUT OFFS AND THEIR INTERACTION AND EVENTUAL MERGER. GIVEN
THE LOCATIONS OF THE VORTICITY THAT WILL GIVE RISE TO THIS SCENARIO
(GIVEN AT END OF SHORT TERM)...MUCH REMAINS UNCERTAIN AND SUBJECT
TO CHANGE BASED ON THE PHASING TIME...DEGREE...LOCATION AND THEN THE
ULTIMATE SFC RESPONSE.
THERE ARE SOME GENERAL THEMES IN MOST OF THE GUIDANCE. ONE CUT
OFF OVER THE MID WEST LIFTS NORTHEAST INTO THE RIDGE OVER THE
EASTERN SEABOARD WEDNESDAY. THE SECOND DIVES SOUTH OUT OF CENTRAL
CANADA. THEY DUMBBELL AROUND EACH OTHER AND MERGE BY THEN END OF
THE WEEK. HWVR POSITIONS RANGE FM CENTERED N OF YUL (GEM)..TO NJ
(GFS) TO OHIO (ECMWF).
WHAT IS MOST CONCRETE AT THIS POINT IS WEDNESDAY THE FIRST 500HPA
CUT OFF MOVES FM MIDWEST INTO GRT LAKES AND PUSHES AN OCCLUDED
FRONT INTO NYS LATE IN THE DAY. THE GFS/GEM AND ECMWF SHOW THIS
SCENARIO WITH THAT CANADIAN ABOUT 6 HOURS FASTER WITH PCPN. WILL
KEEP IT DRY IN THE MORNING WITH CHC POPS AFTN AND WED NIGHT.
THE TIMING ISSUES BECOME MORE ACUTE FROM THURSDAY ON. THURSDAY
THE GFS PUTS FCA IN DRY SLOT AHEAD OF NEXT FRONTAL SYSTEM PUSHING
ACROSS FCA. THE GEM/ECM BRING THE NEXT FRONTAL SYSTEM THROUGH.
IN SUMMARY THE LONG RANGE PERIOD GENERAL THEMES ARE FAIRLY
CLEAR...BUT TIMING IS ALL OVER. OTHER THAN WED WILL LEAVE MUCH OF
THE EARLIER HPC BASED LONG RANGE IN PLACE WITH JUST SOME TWEAKS TO
IMPROVE COORDINATION. TO CHANGE IT TO GMOS AT THIS TIME WILL JUST
INCREASE THE FLIP FLOP FACTOR.
&&
AVIATION /08Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE REGION THROUGH SUNDAY. TRICKY
CALL AT ALL TAF SITES THROUGH AT LEAST 12Z/SUN...AS HIGHER STRATUS
DECK AS ERODED...LEAVING SKIES MAINLY CLEAR...AND WITH LIGHT WINDS
AND A SOMEWHAT MOIST BOUNDARY LAYER...MAY PROMOTE PATCHY FOG
AND/OR LOWER CLOUDS TO DEVELOP. HOWEVER...LATEST 11-3.9 IR
SATELLITE INDICATES PREVIOUS STRATUS DECK EXPANDING BACK TO THE
W...AS WINDS AROUND 925-975 MB VEER INTO THE NE. BOTTOM LINE...LOW
CONFIDENCE ON WHETHER IFR CONDITIONS DEVELOP AT THE TAF SITES OVER
THE NEXT 3-6 HOURS...HIGHLY DEPENDENT ON THE HIGHER CLOUD DECK.
FOR NOW...HAVE INDICATED SEVERAL TEMPOS FOR IFR CONDITIONS...MOST
LIKELY AROUND 12Z...ESP AT KGFL AND KALB.
AFTER 12Z/SUN...ANY IFR CONDITIONS SHOULD LIFT INTO MVFR
CIGS...WHICH COULD LAST UNTIL 15Z-17Z. THEREAFTER...EXPECT VFR
CONDITIONS FOR THIS AFTERNOON INTO THIS EVENING. ADDITIONAL
MVFR/IFR VSBYS/CIGS MAY REDEVELOP TOWARD 06Z/MON.
WINDS WILL REMAIN LIGHT...MAINLY FROM THE N TO NE AT LESS THAN 5
KT THROUGH DAYBREAK...AND NE TO E AT 5-10 KT DURING SUNDAY. WINDS
WILL THEN BECOME LIGHT/VARIABLE SUNDAY NIGHT.
OUTLOOK...
SUN NITE...VFR...NO SIG WX.
MON-TUE...VFR-MVFR...CHC OF RAIN.
WED...VFR...CHC OF SHOWERS.
&&
.HYDROLOGY...
WITH DRY CONDITIONS EXPECTED TO LAST AT LEAST INTO MONDAY RIVERS
WILL CONTINUE RECEDE THROUGH MONDAY. THE NEXT THREAT OF RAIN WILL
BE LATE MONDAY INTO TUESDAY. CONSENSUS OF MODELS IS FOR 0.10 TO
0.70 INCHES MAINLY IN THE SOUTHEAST. BUT ALOT OF UNCERTAINTY
REMAINS WITH THE STORM TRACK AND AMOUNTS COULD VARY. THIS EVENT
SHOULD HAVE MODEST IMPACT ON RIVERS AND STREAMS. FURTHER OUT AN
UNSETTLED PERIOD OF WEATHER THURSDAY INTO THE WEEKEND COULD RESULT
IN SIGNIFICANT PRECIPITATION AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SNYDER
NEAR TERM...KL
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...KL
HYDROLOGY...SNYDER
000
FXUS61 KALY 220644
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
144 AM EST SUN NOV 22 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL COVER THE NORTHEAST TO START THE
WEEK. IT WILL SLIDE EAST INTO THE MARITIMES AND OFFSHORE LATE MONDAY.
OUR WEATHER WILL TURN UNSETTLED MUCH OF THE UPCOMING WEEK. THE FIRST
LOW PRESSURE AREA WILL MOVE NORTHEAST FROM THE CAROLINA COAST
OFFSHORE MONDAY NIGHT AND TUESDAY. THEN MIDWEEK A SERIES OF MUCH
STRONGER STORMS WILL MOVE THOUGH THE MIDWEST AND GREAT LAKES.
&&
.NEAR TERM /THROUGH TODAY/...
MOISTURE TRAPPED BENEATH LOW LEVEL SUBSIDENCE INVERSION WILL KEEP
PATCHY LOW CLOUDS AROUND THROUGH AT LEAST LATE THIS MORNING. IN
FACT...WHERE SOME BREAKS HAVE DEVELOPED...CLOUDS MAY ACTUALLY
REDEVELOP AROUND OR JUST AFTER SUNRISE ONCE SHALLOW MIXING
DEVELOPS. EVENTUALLY...AS THE LOW LEVEL FLOW VEERS INTO A MORE NE
DIRECTION...SOME DOWNSLOPING OFF THE HIGHER TERRAIN TO OUR N/E
SHOULD ALLOW FOR MORE BREAKS IN THE CLOUDS TO DEVELOP THIS
AFTERNOON...ESP FROM THE HUDSON RIVER VALLEY EASTWARD. CLOUDS MAY
PERSIST LONGER...PERHAPS WELL INTO THE AFTERNOON...ACROSS WESTERN
PORTIONS OF THE REGION...FROM THE SW DACKS...WESTERN MOHAWK VALLEY
INTO THE SCHOHARIE VALLEY AND NE CATSKILLS.
AS FOR MAX TEMPS...GIVEN THE EXPECTATION FOR SHALLOW MIXING...MAINLY
TO 925-950 MB...WE EXPECT MAXES TO BE A BIT COOLER THAN SAT...ESP
GIVEN A SLIGHTLY COLDER START...ALONG WITH THE EXPECTATION FOR
CLOUDS THROUGH THE MORNING. SO...GENERALLY SIDED CLOSE TO THE COOLER
MET MOS...WITH MAXES GENERALLY REACHING AROUND 50 WITHIN MUCH OF THE
HUDSON RIVER VALLEY...EXCEPT LOWER/MID 50S ACROSS THE MID HUDSON
VALLEY...WITH MAINLY 40S ACROSS HIGHER ELEVATIONS WITHIN WESTERN NEW
ENGLAND AND WESTERN PORTIONS OF THE REGION.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
PERIOD STARTS WITH RIDGING AND SUBSIDENCE THROUGHOUT THE ATMOSPHERE
WITH 572DM HIGH EVEN AT 500HPA. 500HPA TROF LINGERS SOUTH OF RGN
FM MASON DIXON LINE TO LONG IS NY WHILE IMPRESSIVE SFC HIGH
DOMINATES THE NORTHEAST QUARTER OF THE NATION AND IS CENTERED OVER
THE MARITIMES. WHILE THE DIRTY HIGH PHASE WITH MOISTURE TRAPPED
UNDER THE INVERSION WILL HAVE ENDED EARLY SUNDAY THE NEW GUIDANCE
SUGGESTS THE MOIST BOUNDARY LAYER REMAINS AND SHOWS MARINE LAYER
MOISTURE OR FOG/STRATUS CREEPING BACK UP THE HUDSON VALLEY EVEN AS
EARLY AS LATE SUNDAY NIGHT EARLY MONDAY MORNING. THE WITH ALL THE
MODELS AND STATISTICAL GUID KEEPING THE FLOW EAST TO NORTHEAST
BELOW THE INVERSION LAYER...WILL BRING CLOUDS INTO THE SOUTHEAST.
THE NAM IS THE ONLY LESS AGGRESSIVE MODEL WITH ADVECTING THIS
MARINE LAYER MOISTURE WHILE THE WRF/GEM/GFS SHOW IT BLO 900HPA.
MUCH LIKE LAST WEEK WHEN THIS SAME SCENARIO OCCURRED CLOUDS SHOULD
BARELY MAKE ALBANY MONDAY MORNING AND THESE MAY ERODE FOR A TIME.
FROM ALB N & W WILL STAY FAIR A GOOD PART OF THE DAY TILL BOUNDARY
LEVEL FLOW TURNS SE-S AND MOISTURE STREAMS NORTH. IN SOUTHEAST
LOOKING AT AREAS OF MORNING STRATUS AND FOG THAT MAY OR MAY NOT
BURN OFF BEFORE THE CLOUDS FROM NEXT SYSTEM OVERSPREAD THOSE
AREAS.
MARINE LAYER MOISTURE ADVECTION SHOULD BE WEAK TILL 500HPA TROF
THAT WAS LAYING DORMANT ACROSS THE MID ATLC BEGINS MOVES NORTH
INTO OUR REGION MONDAY. MODELS SUGGEST A COASTAL DEVELOPMENT BUT
ITS WELL OFFSHORE AND ITS MAIN IMPACT IS TO ENHANCE THE MARINE
LAYER INFLOW. THIS MOISTURE AND THE PASSAGE OF SEVERAL 500HPA
SHORT WAVES WILL PRODUCE CLOUDS ACROSS THE AREA AND AN INCR CHC
OF -RN AND DZ MONDAY NIGHT AND TUES MAINLY IN THE SOUTHEAST.
INITIALLY TUESDAY NIGHT THE SFC LOW DEPARTS WELL OFFSHORE. 500HPA
RIDGE REBUILDS ALONG THE SEABOARD. WELL TO OUR WEST THE STAGE IS
BEING SET FOR A COMPLEX PATTERN TO END THE WEEK. TUES NT WERE
STUCK WITH MORE RESIDUAL LOW LEVEL MOISTURE AND NOT MUCH MORE THAN
DRIZZLE AND CLOUDS.
MEANWHILE TUESDAY NIGHT TWO CUTOFFS WILL BE SETTING UP. ONE IN
THE MISSISSIPPI VALLEY THE OTHER IN SOUTH CENTRAL CANADA. LOOKING
AT THE 1.5PVU SFCS THE ORIGINS OF THESE SYSTEMS ARE THREE
PART. 1) JUST OFF THE BRITISH COLUMBIA ALASKA PANHANDLE
COAST...2) IN THE FAST FLOW IN THE CENTRAL PACIFIC NORTH OF
HAWAII AND 3) ALONG ALASKA`S BROOKS RANGE. OBVIOUSLY MANY
QUESTIONS REMAIN ABOUT THE PHASING PROCESS AND THE RESULTANT SFC
WEATHER. MORE IN THIS IN LONG TERM SECTION.
THROUGH TUESDAY NIGHT THERES A FAIR AMOUNT OF MODEL CONSISTENCY
EXCEPT WITH REGARD TO THE MAGNITUDE OF THE MARINE LAYER INFLOW
MONDAY AS DISCUSSED ABOVE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
MONDAY INTO MONDAY NIGHT THE LINGERING 500HPA TROF FROM THE MID
ATLC STATES PHASES WITH A TROF LIFTING NE FM GULF COAST STATES. STILL
CONSIDERABLE VARIATION IN THE PHASING AND THE SFC RESPONSE...BUT
GFS/ECMWF AND NAM PRODUCE A COASTAL LOW MONDAY NT THAT LIFTS NE.
THE MDL TRACKS ARE STILL QUITE VARIED. THE GFS/ECMWF KEEP FCA ON
PERIPHERY OF SYSTEM WITH THREAT OF ONLY LT RN IN SE FCA...THE NAM
A BIT MORE AGGRESSIVE WITH QPF AND FURTHER WEST. BOTTOM LINE WILL
INTRODUCE CHC POPS MON NT INTO TUES MAINLY IN SE HALF OF FCA.
ONCE THIS FIRST SYSTEM PASSES THERE`S AS MUCH AGREEMENT AS YOU
USUALLY GET IN THE EFP FOR THE REST OF THE PERIOD. THERE ARE FEW
SIGNIFICANT DIFFERENCES BWTN HPC...THE ECMWF THAT JUST CAME IN AND
THE GFS. WILL POPULATE WITH HPC GRIDS FOR EFP.
IT APPEARS THIS EXTENDED PERIOD WILL BE A GAME CHANGER. AFTER
TUESDAYS WEAK COASTAL DEPARTS A SERIES OF SHORT WAVES PHASE INTO A
DEEP AND LARGE 500HPA CUT OFF OVER THE MISSISSIPPI VALLEY AS
ANOTHER CUTOFF ORGANIZES OVER SOUTH CENTRAL CANADA. THESE SYSTEMS
INTERACT WITH EACH OTHER DURING THE EXTENDED PERIOD CREATING A
DUMBELLING ACTION AROUND EACH OTHER OVER THE GRTLKS..MIDWEST AND
UPR GRT PLAINS FOR MUCH OF THE WEEK TILL THEY PHASE INTO A MASSIVE
CUTOFF LOVER THE EASTERN SEABOARD TO END THE WEEK. THE MAIN STORM
TRACKS WILL PASS TO OUR WEST AT FIRST...WITH THE FINAL ONE A
COASTAL BY THE WEEKEND. THE RESULT WILL BE AN UNSETTLED PERIOD AS
WE HEAD INTO THE THANKSGIVING TRAVEL AND HOLIDAY PERIOD. THERE
WILL BE SEVERAL FRONTAL PASSAGES AND THEIR BOUTS OF PRECIPITATION.
TEMPS WILL REMAIN NR OR ABOVE NORMAL TILL THE END OF THE WEEK WHEN
IT WILL TURN NOTICEABLY COLDER.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE REGION THROUGH SUNDAY.
TRICKY CALL AT ALL TAF SITES THROUGH AT LEAST 12Z/SUN...AS HIGHER
STRATUS DECK AS ERODED...LEAVING SKIES MAINLY CLEAR...AND WITH
LIGHT WINDS AND A SOMEWHAT MOIST BOUNDARY LAYER...MAY PROMOTE
PATCHY FOG AND/OR LOWER CLOUDS TO DEVELOP. HOWEVER...LATEST
11-3.9 IR SATELLITE INDICATES PREVIOUS STRATUS DECK EXPANDING BACK
TO THE W...AS WINDS AROUND 925-975 MB VEER INTO THE NE. BOTTOM
LINE...LOW CONFIDENCE ON WHETHER IFR CONDITIONS DEVELOP AT THE TAF
SITES OVER THE NEXT 3-6 HOURS...HIGHLY DEPENDENT ON THE HIGHER
CLOUD DECK. FOR NOW...HAVE INDICATED SEVERAL TEMPOS FOR IFR
CONDITIONS...MOST LIKELY AROUND 12Z...ESP AT KGFL AND KALB.
AFTER 12Z/SUN...ANY IFR CONDITIONS SHOULD LIFT INTO MVFR
CIGS...WHICH COULD LAST UNTIL 15Z-17Z. THEREAFTER...EXPECT VFR
CONDITIONS FOR THIS AFTERNOON INTO THIS EVENING. ADDITIONAL
MVFR/IFR VSBYS/CIGS MAY REDEVELOP TOWARD 06Z/MON.
WINDS WILL REMAIN LIGHT...MAINLY FROM THE N TO NE AT LESS THAN 5
KT THROUGH DAYBREAK...AND NE TO E AT 5-10 KT DURING SUNDAY. WINDS
WILL THEN BECOME LIGHT/VARIABLE SUNDAY NIGHT.
OUTLOOK...
SUN NITE...VFR...NO SIG WX.
MON-TUE...VFR-MVFR...CHC OF RAIN.
WED...VFR...CHC OF SHOWERS.
&&
.HYDROLOGY...
WITH DRY CONDITIONS EXPECTED TO LAST AT LEAST INTO MONDAY RIVERS
WILL CONTINUE RECEDE THROUGH MONDAY. THE NEXT THREAT OF RAIN WILL
BE LATE MONDAY INTO TUESDAY. CONSENSUS OF MODELS IS FOR 0.10 TO
0.70 INCHES MAINLY IN THE SOUTHEAST. BUT ALOT OF UNCERTAINTY
REMAINS WITH THE STORM TRACK AND AMOUNTS COULD VARY. THIS EVENT
SHOULD HAVE MODEST IMPACT ON RIVERS AND STREAMS. FURTHER OUT AN
UNSETTLED PERIOD OF WEATHER THURSDAY INTO THE WEEKEND COULD RESULT
IN SIGNIFICANT PRECIPITATION AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SNYDER
NEAR TERM...KL
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...KL
HYDROLOGY...SNYDER
000
FXUS61 KALY 220532
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
1232 AM EST SUN NOV 22 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL COVER THE NORTHEAST TO START THE
WEEK. IT WILL SLIDE EAST INTO THE MARITIMES AND OFFSHORE LATE
MONDAY. CLOUDS WILL HANG IN OVERNIGHT WEST OF THE HUDSON VALLEY BUT
SKIES ARE EXPECTED TO CLEAR TOWARD DAYBREAK. MOSTLY FAIR WEATHER
MONDAY WILL BE FOLLOWED BY MORE UNSETTLED WEATHER LATER IN THE WEEK
AS A SERIES OF DISTURBANCES AFFECT THE REGION.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
SKIES HAVE CLEARED FROM THE HUDSON VALLEY EASTWARD EXCEPT FOR A
SMALL PATCH OF CLOUDS JUST WEST OF THE NORTHERN TACONICS ALONG AND
JUST WEST OF THE NY/VT/MA STATE LINE. TEMPERATURES ARE HOLDING
WARMER THAN PREVIOUSLY FORECAST SO HAVE UPDATED GRIDS USING A
BLEND OF THE MAV/MOS...RUC...AND LATEST OBS AND TRENDS. WITH
SKIES MOSTLY CLEAR OVER THE HUDSON VALLEY SOUTH OF ALBANY AND
THE EASTERN FRINGES OF THE CATSKILLS HAVE ALSO EXPANDED THE AREA
OF VALLEY FOG FARTHER SOUTH. ASIDE FROM GLENS FALLS...POUGHKEEPSIE...
AND MONTGOMERY...ALL WHICH HAVE PLUMMETED INTO THE MID 30S...TEMPS
ACROSS THE REGION ARE HANGING IN THE LOW AND MID 40S...EVEN OVER
SOME OF THE AREA WHERE SKIES HAVE CLEARED. HAVE UPDATED SKY
GRIDS TO REFLECT LATEST OBS AND TRENDS. LATEST SATELLITE IMAGES
SHOW LITTLE CHANGE IN THE AREA OF CLOUDS THAT COVER UPSTATE NEW
YORK WEST OF THE HUDSON VALLEY ALONG WITH ADJACENT PARTS OF PA...
LAKES ONTARIO AND ERIE...AND SOUTHERN ONTARIO.
***PREVIOUS NEAR TERM...ISSUED AT 245 PM TODAY...***
SURFACE HIGH IN THE GREAT LAKES AND OH VALLEY CONTINUES TO GRADUALLY
BUILD INTO THE REGION. WEST TO NORTHWEST FLOW ACROSS THE LAKES AND
AN INVERSION AT THE BOUNDARY LAYER HAS RESULTED IN WIDESPREAD CLOUD
COVER. HOWEVER...AREAS IN LEE OF THE EASTERN CATSKILLS...BERKSHIRES
AND SOUTHERN GREEN MOUNTAINS HAVE SEEN RELATIVELY LITTLE CLOUD COVER
DUE TO DOWNSLOPE.
RECENT SATELLITE TRENDS ARE CONSISTENT WITH TRENDS SEEN IN
GUIDANCE...WITH CLEARING AND DRYING BEGINNING TO WORK SOUTH FROM
NEAR THE CANADIAN BORDER. THIS CLEARING AND DRYING WILL BUILD SOUTH
THROUGH THE EVENING AND NIGHT...BUT THERE IS SOME QUESTION ABOUT
HOW FAR WEST THE CLEARING WILL GET...DUE TO PROXIMITY TO LAKE
ONTARIO. FOR AREAS AROUND AND EAST OF THE HUDSON VALLEY...CLEARING
SHOULD SPREAD ACROSS THE REGION BY THE EARLY MORNING HOURS. AREAS
OF THE WESTERN MOHAWK VALLEY TO SCHOHARIE VALLEY AND PARTS OF THE
CATSKILLS MAY BE A BIT SLOWER TO CLEAR. STILL...BY SUNRISE...
SUGGESTING ALL AREAS WILL CLEAR. WITH AT LEAST A COUPLE/FEW HOURS
OF CLEARING BEFORE SUNRISE...TEMPERATURES SHOULD FALL TO NEAR
GUIDANCE LEVELS...EVEN THOUGH TEMPERATURES WILL NOT FALL MUCH UNTIL
CLEARING OCCURS.
UPSTREAM SURFACE DEW POINTS NOT TOO DRY...SO LOW TEMPERATURES SHOULD
NOT BE MUCH BELOW GUIDANCE IN AREAS THAT SEE THE LONGEST PERIOD OF
CLEARING...AND MAYBE A BIT ABOVE GUIDANCE WHERE CLEARING IS MOST
DELAYED. MOST TEMPERATURE BUST POTENTIAL TONIGHT LOOKS TO BE IN THE
WESTERN MOHAWK VALLEY...SCHOHARIE VALLEY AND PARTS OF THE
CATSKILLS...WHERE TIMING OF CLEARING IN QUESTION.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM MONDAY/...
RATHER IMPRESSIVE RIDGE OVER RGN FOR THIS PERIOD AT SFC AND ALOFT.
THE 500HPA SHORT WAVE AXIS (FM W MD TO CAPE COD) WILL BE EXITING
THE RGN AT START OF THE PERIOD AND TAKING WITH IT MOST OF THE
FORCING THAT RESULTED IN THE CLOUDS THAT WERE TRAPPED UNDER THE
INVERSION. WRF ALSO SHOWS DRYING AND DRY AIR ADVECTION JUST PRIOR
TO THIS PERIOD. SO SUNDAY SHOULD BE A SUNNY DAY WITH ABV NORMAL
TEMPS AND ANY RESIDUAL CLOUDS WILL GO QUICKLY.
FOR THE MOST PART WE HAVE MODEL CONSISTENCY (ECMWF/GEM/GFS/NAM)
FOR SYSTEM PLACEMENT AND TIMING THROUGH MONDAY. THE EXCEPTION IS
THE NAM NOW PUSHES THREAT OF RAIN INTO SE FCA LATE MONDAY...ABOUT
3-6 HOURS FASTER THAN REST OF THE CROWD. BUT THE CONSENSUS
REMAINS FOR A PARTLY SUNNY AND DRY DAY IN MOST OF THE AREA WITH
JUST CHC POPS ALONG THE SOUTHERN PERIPHERAL COUNTIES. SO THERE
SHOULD BE LITTLE CHANGE IN THE FORECAST.
THE OTHER DISCONTINUITY IS THE MAV AND MET TEMPS ARE ABOUT 5-10
DEGREES APART SUNDAY...THE MET BEING THE COLD ONE. THIS IN SPITE
OF BOTH MODELS INDICATING SIMILAR SENSIBLE WEATHER (SUNNY..LIGHT
WINDS..UNDER HIGH), AND HAVING ABOUT THE SAME 925 HPA FORECASTED
TEMPS (3-5C)AS WELL. THIS DIFFERENCE IN THE MET/MAV IS REFLECTED
IN THEIR MODEL SOUNDINGS AND PARTICULARLY AROUND MAX TEMP TIME @
18UTC. WHILE THE NEW NAM PHYSICS HAVE GENERALLY BEEN BETTER SINCE
THE UPGRADE SOMETHING SEEMS SQUIRRELLY IN THE MET TEMPS SUNDAY.
TODAY SO FAR WHERES THERE NO SUN TEMPS ARE STILL MID 40S TO AROUND
50...AND WELL INTO THE 50S WHERE THE SUN IS SHINING. COULD JUST
BLEND THE TWO...BUT GIVEN THE COMPARISON TO TODAY..FCST WILL GO
WITH THE MAV TEMPS
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MONDAY INTO MONDAY NIGHT THE LINGERING 500HPA TROF FROM THE MID
ATLC STATES PHASES WITH A TROF LIFTING NE FM GULF COAST STATES. STILL
CONSIDERABLE VARIATION IN THE PHASING AND THE SFC RESPONSE...BUT
GFS/ECMWF AND NAM PRODUCE A COASTAL LOW MONDAY NT THAT LIFTS NE.
THE MDL TRACKS ARE STILL QUITE VARIED. THE GFS/ECMWF KEEP FCA ON
PERIPHERY OF SYSTEM WITH THREAT OF ONLY LT RN IN SE FCA...THE NAM
A BIT MORE AGGRESSIVE WITH QPF AND FURTHER WEST. BOTTOM LINE WILL
INTRODUCE CHC POPS MON NT INTO TUES MAINLY IN SE HALF OF FCA.
ONCE THIS FIRST SYSTEM PASSES THERE`S AS MUCH AGREEMENT AS YOU
USUALLY GET IN THE EFP FOR THE REST OF THE PERIOD. THERE ARE FEW
SIGNIFICANT DIFFERENCES BWTN HPC...THE ECMWF THAT JUST CAME IN AND
THE GFS. WILL POPULATE WITH HPC GRIDS FOR EFP.
IT APPEARS THIS EXTENDED PERIOD WILL BE A GAME CHANGER. AFTER
TUESDAYS WEAK COASTAL DEPARTS A SERIES OF SHORT WAVES PHASE INTO A
DEEP AND LARGE 500HPA CUT OFF OVER THE MISSISSIPPI VALLEY AS
ANOTHER CUTOFF ORGANIZES OVER SOUTH CENTRAL CANADA. THESE SYSTEMS
INTERACT WITH EACH OTHER DURING THE EXTENDED PERIOD CREATING A
DUMBELLING ACTION AROUND EACH OTHER OVER THE GRTLKS..MIDWEST AND
UPR GRT PLAINS FOR MUCH OF THE WEEK TILL THEY PHASE INTO A MASSIVE
CUTOFF LOVER THE EASTERN SEABOARD TO END THE WEEK. THE MAIN STORM
TRACKS WILL PASS TO OUR WEST AT FIRST...WITH THE FINAL ONE A
COASTAL BY THE WEEKEND. THE RESULT WILL BE AN UNSETTLED PERIOD AS
WE HEAD INTO THE THANKSGIVING TRAVEL AND HOLIDAY PERIOD. THERE
WILL BE SEVERAL FRONTAL PASSAGES AND THEIR BOUTS OF PRECIPITATION.
TEMPS WILL REMAIN NR OR ABOVE NORMAL TILL THE END OF THE WEEK WHEN
IT WILL TURN NOTICEABLY COLDER.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE REGION THROUGH SUNDAY.
TRICKY CALL AT ALL TAF SITES THROUGH AT LEAST 12Z/SUN...AS HIGHER
STRATUS DECK AS ERODED...LEAVING SKIES MAINLY CLEAR...AND WITH
LIGHT WINDS AND A SOMEWHAT MOIST BOUNDARY LAYER...MAY PROMOTE
PATCHY FOG AND/OR LOWER CLOUDS TO DEVELOP. HOWEVER...LATEST
11-3.9 IR SATELLITE INDICATES PREVIOUS STRATUS DECK EXPANDING BACK
TO THE W...AS WINDS AROUND 925-975 MB VEER INTO THE NE. BOTTOM
LINE...LOW CONFIDENCE ON WHETHER IFR CONDITIONS DEVELOP AT THE TAF
SITES OVER THE NEXT 3-6 HOURS...HIGHLY DEPENDENT ON THE HIGHER
CLOUD DECK. FOR NOW...HAVE INDICATED SEVERAL TEMPOS FOR IFR
CONDITIONS...MOST LIKELY AROUND 12Z...ESP AT KGFL AND KALB.
AFTER 12Z/SUN...ANY IFR CONDITIONS SHOULD LIFT INTO MVFR
CIGS...WHICH COULD LAST UNTIL 15Z-17Z. THEREAFTER...EXPECT VFR
CONDITIONS FOR THIS AFTERNOON INTO THIS EVENING. ADDITIONAL
MVFR/IFR VSBYS/CIGS MAY REDEVELOP TOWARD 06Z/MON.
WINDS WILL REMAIN LIGHT...MAINLY FROM THE N TO NE AT LESS THAN 5
KT THROUGH DAYBREAK...AND NE TO E AT 5-10 KT DURING SUNDAY. WINDS
WILL THEN BECOME LIGHT/VARIABLE SUNDAY NIGHT.
OUTLOOK...
SUN NITE...VFR...NO SIG WX.
MON-TUE...VFR-MVFR...CHC OF RAIN.
WED...VFR...CHC OF SHOWERS.
&&
.HYDROLOGY...
WITH DRY CONDITIONS EXPECTED TO LAST AT LEAST INTO MONDAY RIVERS
WILL CONTINUE RECEDE THROUGH MONDAY. THE NEXT THREAT OF RAIN WILL
BE LATE MONDAY INTO TUESDAY. CONSENSUS OF MODELS IS FOR 0.10 TO
0.70 INCHES MAINLY IN THE SOUTHEAST. BUT ALOT OF UNCERTAINTY
REMAINS WITH THE STORM TRACK AND AMOUNTS COULD VARY. THIS EVENT
SHOULD HAVE MODEST IMPACT ON RIVERS AND STREAMS. FURTHER OUT AN
UNSETTLED PERIOD OF WEATHER THURSDAY INTO THE WEEKEND COULD RESULT
IN SIGNIFICANT PRECIPITATION AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SNYDER
NEAR TERM...RCK
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...KL
HYDROLOGY...SNYDER
000
FXUS61 KOKX 220527
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1227 AM EST SUN NOV 22 2009
.SYNOPSIS...
HIGH PRESSURE BUILDS ACROSS EASTERN CANADA...AND INTO THE
MARITIMES THOROUGH MONDAY. AN AREA OF LOW PRESSURE WILL DEVELOP
OFF THE SOUTHEAST US COAST SUNDAY...THEN MOVE UP COAST
MONDAY...PASSING SOUTH AND EAST OF LONG ISLAND THROUGH TUESDAY. WEAK
HIGH PRESSURE BUILDS IN FROM THE NORTH WEDNESDAY. ANOTHER STORM
SYSTEM MAY IMPACT THE TRI-STATE TO CLOSE THE UPCOMING WORK WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
MOSTLY CLEAR SKIES EXPECTED AS WINDS DIMINISH. THIS COMBINATION
WILL RESULT IN DECENT IF NOT IDEAL RADIATIONAL COOLING FOR AT
LEAST A FEW HOURS TONIGHT. FORECAST LOWS...AND DEWPOINTS APPROACH
THE MID 30S IN SPOTS...SO EARLY MORNING FOG IS A POSSIBILITY. THIS
IS NOT IN THE GRIDS AT THIS POINT GIVEN THAT DECOUPLING SHOULD
ONLY LAST A FEW HOURS AS NE WINDS PICK UP A BIT.
UNDERCUT MOS IN GENERAL IN THE NORMALLY COOLER SPOTS ACROSS
ORANGE/PUTNAM COUNTY AND THE PINE BARRENS OF LI. PERSISTENCE AND
MOS VERY CLOSE ELSEWHERE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/...
DEEP LAYER RIDGE PASSES NORTH OF THE CWA SUNDAY...ALLOWING
EASTERLY FLOW ON THE SOUTH SIDE TO INCREASE. ALL IN ALL A DECENT
DAY WITH HIGHS NEAR OR SLIGHTLY BELOW CLIMATOLOGICAL NORMS WITH
EAST WINDS.
TRICKY TEMP FORECAST SUNDAY NIGHT...AS COLD AIR DAMMING AND LOW
LEVEL COLD AIR ADVECTION CONTINUE FROM THE NORTH AND EAST. THERE
MAY AGAIN BE A PERIOD OF DECOUPLING...THUS FORECAST LOW TEMPS ARE
EXPECTED TO END UP CLOSE TO TONIGHT`S. THIS PERIOD IS PERHAPS THE
LOWEST CONFIDENCE TEMP FORECAST OF THE SHORT TERM. IF SURFACE
WINDS STAY UP...AND INCREASING MOISTURE FROM A DEVELOPING SURFACE
LOW GET HERE EARLIER THAN EXPECTED...LOWS WILL BE MUCH WARMER THAN
FORECAST.
MODEL SOLUTIONS STILL DIVERGE ON THE TRACK AND INTENSITY OF A
DIFFUSE COASTAL LOW...BUT THE WIND FIELDS ARE BIT MORE ALIGNED.
PRECIP EXPECTED TO HOLD OFF UNTIL MONDAY NIGHT...ALTHOUGH A BRIEF
PERIOD OF LIGHT OVERRUNNING RAIN POSSIBLE MONDAY AFTERNOON.
INCREASED POP TO LIKELY FOR ABOUT THE EASTERN TWO THIRDS OF THE
CWA TUESDAY MORNING...BUT THIS ULTIMATELY DEPENDS ON IF THE LOW
CENTER PASSES CLOSE ENOUGH TO PUT THE AREA IN THE BEST LIFT. THE
NAM CONTINUES TO BE THE MOST ROBUST IN TERMS OF QPF...BUT THE 18Z
RUN HAS BACKED OFF FROM ITS 1 TO 1.5 INCH FORECAST EARLIER TODAY.
LIGHT RAIN...PRIMARILY WRAP AROUND...POSSIBLE INTO TUESDAY NIGHT.
NOT A WHOLE LOT OF TEMP VARIATION MONDAY NIGHT THROUGH TUESDAY
NIGHT...ESPECIALLY NEAR THE COAST.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
LOW PRESSURE DEPARTS THE REGION TUESDAY NIGHT WITH CHANCE POPS
FOR -RA ENDING. SOUTHWEST FLOW ALOFT DEVELOPS WEDNESDAY AS H5 LOW
DROPS INTO THE OHIO VALLEY. H3 JET PRODUCES SOME LIFT...BUT
FORCING OTHERWISE IS WEAK AS EVIDENCED BY THE TIME HEIGHTS. WITH
MARGINAL MOISTURE...ONLY LIGHT PRECIPITATION EXPECTED AT THIS TIME.
A LULL SETTLES IN WEDNESDAY NIGHT INTO THURSDAY...THEN THE FOCUS SHIFTS
TO LATE THURSDAY AND FRIDAY. ANOTHER H5 LOW DROPS INTO THE OHIO VALLEY
WITH A COMPLEX REFLECTION AT THE SURFACE. MODELS HINT AT LOW
PRESSURE DEVELOPING ALONG THE NORTHERN GULF COAST AND TRACKING
NORTHEASTWARD OFF THE ATLANTIC COAST...WITH A SECOND LOW
DEVELOPING OVER THE EASTERN GREAT LAKES. ALL THOUGH THERE IS A
SPREAD IN THE MODEL SOLUTIONS...IT APPEARS A SHOT OF RA ON TRACK
DURING THE PERIOD. MAIN ISSUE MAY TURN OUT TO BE THE WIND IF THE
12Z GFS/ECMWF SOLUTIONS ARE CLOSE AND A 980 MB LOW OCCLUDES OVER
NORTHERN NEW ENGLAND SATURDAY MORNING.
&&
.AVIATION /05Z SUNDAY THROUGH THURSDAY/...
NORTHERLY WINDS 5 TO 10 KT OVERNIGHT WILL VEER NORTHEAST DURING
THE DAY TIME AS HIGH PRESSURE SETTLES OVER SOUTHEASTERN CANADA. TOWARD
SUNRISE...A FEW TERMINAL SITES COULD SEE SOME RADIATION FOG...MVFR
VISIBILITIES IF WINDS DECOUPLE (KSWF/KGON)...BUT CONFIDENCE LOW
TO MODERATE IN THIS HAPPENING. NYC METRO WILL BE OK DUE TO AMPLE
MIXING/HEAT ISLAND.
OVERALL...VFR TODAY IN NORTH TO NORTHEAST FLOW. BETTER CHANCE FOR
MVFR CEILINGS/VISIBILITIES SUNDAY NIGHT IN NORTHEAST FLOW.
OUTLOOK 06Z MONDAY THROUGH THURSDAY...
SUNDAY NIGHT...POSSIBLE SUB VFR.
MONDAY...SUB-VFR POSSIBLE.
MONDAY NIGHT-TUESDAY...SUB-VFR LIKELY.
TUESDAY NIGHT-WEDNESDAY...BECOMING VFR.
THURSDAY...SUB-VFR POSSIBLE.
&&
.MARINE...
NORTHERLY FLOW BECOMES NORTHEAST OVERNIGHT...AS HIGH PRESSURE
SETTLES INTO EASTERN CANADA. THE PRESSURE GRADIENT STRENGTHENS
THROUGH SUNDAY EVENING WITH LOWERING PRESSURE TO THE SOUTH. SMALL
CRAFT CONDITIONS EXPECTED TO BEGIN ON OCEAN WATERS SUNDAY EVENING.
EXPECT WINDS TO INCREASE FROM SOUTH TO NORTH...AND IT IS POSSIBLE
THE THE WATERS RIGHT ALONG THE COAST OF LONG ISLAND WILL NOT SEE
25 KTS UNTIL MONDAY MORNING.
SMALL CRAFT WIND CONDITIONS...WITH A FEW GUSTS POSSIBLY
APPROACHING GALE FORCE MONDAY THROUGH TUESDAY.
SCA SEAS ON THE OCEAN LINGER TUESDAY NIGHT INTO WEDNESDAY...THEN BEGIN
TO SUBSIDE AS LOW PRESSURE WEAKENS NORTH OF THE COASTAL WATERS. A
COMPLEX LOW PRESSURE SYSTEM WILL THEN IMPACT THE WATERS FROM LATE
THURSDAY INTO FRIDAY. DEPENDING ON THE EXACT TRACK AND INTENSITY OF
THE SYSTEM...GALES MAY BE POSSIBLE TO CLOSE THE UPCOMING WORK WEEK.
&&
.HYDROLOGY...
DRY THROUGH MONDAY MORNING. A QUARTER TO A HALF AN INCH OF
RAINFALL IS POSSIBLE MONDAY AFTERNOON THROUGH WEDNESDAY. MORE
PRECIPITATION IS EXPECTED TOWARDS THE END OF NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 PM EST MONDAY
FOR ANZ350-353-355.
&&
$$
SYNOPSIS...BS
NEAR TERM...PW/BS
SHORT TERM...BS
LONG TERM...JMC
AVIATION...PW
MARINE...BG/JMC
HYDROLOGY...BS
000
FXUS61 KALY 220307
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
1005 PM EST SAT NOV 21 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL COVER THE NORTHEAST TO START THE
WEEK. IT WILL SLIDE EAST INTO THE MARITIMES AND OFFSHORE LATE
MONDAY. CLOUDS WILL HANG IN OVERNIGHT WEST OF THE HUDSON VALLEY BUT
SKIES ARE EXPECTED TO CLEAR TOWARD DAYBREAK. MOSTLY FAIR WEATHER
MONDAY WILL BE FOLLOWED BY MORE UNSETTLED WEATHER LATER IN THE WEEK
AS A SERIES OF DISTURBANCES AFFECT THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
SKIES HAVE CLEARED FROM THE HUDSON VALLEY EASTWARD EXCEPT FOR A
SMALL PATCH OF CLOUDS JUST WEST OF THE NORTHERN TACONICS ALONG AND
JUST WEST OF THE NY/VT/MA STATE LINE. TEMPERATURES ARE HOLDING
WARMER THAN PREVIOUSLY FORECAST SO HAVE UPDATED GRIDS USING A
BLEND OF THE MAV/MOS...RUC...AND LATEST OBS AND TRENDS. WITH
SKIES MOSTLY CLEAR OVER THE HUDSON VALLEY SOUTH OF ALBANY AND
THE EASTERN FRINGES OF THE CATSKILLS HAVE ALSO EXPANDED THE AREA
OF VALLEY FOG FARTHER SOUTH. ASIDE FROM GLENS FALLS...POUGHKEEPSIE...
AND MONTGOMERY...ALL WHICH HAVE PLUMMETED INTO THE MID 30S...TEMPS
ACROSS THE REGION ARE HANGING IN THE LOW AND MID 40S...EVEN OVER
SOME OF THE AREA WHERE SKIES HAVE CLEARED. HAVE UPDATED SKY
GRIDS TO REFLECT LATEST OBS AND TRENDS. LATEST SATELLITE IMAGES
SHOW LITTLE CHANGE IN THE AREA OF CLOUDS THAT COVER UPSTATE NEW
YORK WEST OF THE HUDSON VALLEY ALONG WITH ADJACENT PARTS OF PA...
LAKES ONTARIO AND ERIE...AND SOUTHERN ONTARIO.
***PREVIOUS NEAR TERM...ISSUED AT 245 PM TODAY...***
SURFACE HIGH IN THE GREAT LAKES AND OH VALLEY CONTINUES TO GRADUALLY
BUILD INTO THE REGION. WEST TO NORTHWEST FLOW ACROSS THE LAKES AND
AN INVERSION AT THE BOUNDARY LAYER HAS RESULTED IN WIDESPREAD CLOUD
COVER. HOWEVER...AREAS IN LEE OF THE EASTERN CATSKILLS...BERKSHIRES
AND SOUTHERN GREEN MOUNTAINS HAVE SEEN RELATIVELY LITTLE CLOUD COVER
DUE TO DOWNSLOPE.
RECENT SATELLITE TRENDS ARE CONSISTENT WITH TRENDS SEEN IN
GUIDANCE...WITH CLEARING AND DRYING BEGINNING TO WORK SOUTH FROM
NEAR THE CANADIAN BORDER. THIS CLEARING AND DRYING WILL BUILD SOUTH
THROUGH THE EVENING AND NIGHT...BUT THERE IS SOME QUESTION ABOUT
HOW FAR WEST THE CLEARING WILL GET...DUE TO PROXIMITY TO LAKE
ONTARIO. FOR AREAS AROUND AND EAST OF THE HUDSON VALLEY...CLEARING
SHOULD SPREAD ACROSS THE REGION BY THE EARLY MORNING HOURS. AREAS
OF THE WESTERN MOHAWK VALLEY TO SCHOHARIE VALLEY AND PARTS OF THE
CATSKILLS MAY BE A BIT SLOWER TO CLEAR. STILL...BY SUNRISE...
SUGGESTING ALL AREAS WILL CLEAR. WITH AT LEAST A COUPLE/FEW HOURS
OF CLEARING BEFORE SUNRISE...TEMPERATURES SHOULD FALL TO NEAR
GUIDANCE LEVELS...EVEN THOUGH TEMPERATURES WILL NOT FALL MUCH UNTIL
CLEARING OCCURS.
UPSTREAM SURFACE DEW POINTS NOT TOO DRY...SO LOW TEMPERATURES SHOULD
NOT BE MUCH BELOW GUIDANCE IN AREAS THAT SEE THE LONGEST PERIOD OF
CLEARING...AND MAYBE A BIT ABOVE GUIDANCE WHERE CLEARING IS MOST
DELAYED. MOST TEMPERATURE BUST POTENTIAL TONIGHT LOOKS TO BE IN THE
WESTERN MOHAWK VALLEY...SCHOHARIE VALLEY AND PARTS OF THE
CATSKILLS...WHERE TIMING OF CLEARING IN QUESTION.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
RATHER IMPRESSIVE RIDGE OVER RGN FOR THIS PERIOD AT SFC AND ALOFT.
THE 500HPA SHORT WAVE AXIS (FM W MD TO CAPE COD) WILL BE EXITING
THE RGN AT START OF THE PERIOD AND TAKING WITH IT MOST OF THE
FORCING THAT RESULTED IN THE CLOUDS THAT WERE TRAPPED UNDER THE
INVERSION. WRF ALSO SHOWS DRYING AND DRY AIR ADVECTION JUST PRIOR
TO THIS PERIOD. SO SUNDAY SHOULD BE A SUNNY DAY WITH ABV NORMAL
TEMPS AND ANY RESIDUAL CLOUDS WILL GO QUICKLY.
FOR THE MOST PART WE HAVE MODEL CONSISTENCY (ECMWF/GEM/GFS/NAM)
FOR SYSTEM PLACEMENT AND TIMING THROUGH MONDAY. THE EXCEPTION IS
THE NAM NOW PUSHES THREAT OF RAIN INTO SE FCA LATE MONDAY...ABOUT
3-6 HOURS FASTER THAN REST OF THE CROWD. BUT THE CONSENSUS
REMAINS FOR A PARTLY SUNNY AND DRY DAY IN MOST OF THE AREA WITH
JUST CHC POPS ALONG THE SOUTHERN PERIPHERAL COUNTIES. SO THERE
SHOULD BE LITTLE CHANGE IN THE FORECAST.
THE OTHER DISCONTINUITY IS THE MAV AND MET TEMPS ARE ABOUT 5-10
DEGREES APART SUNDAY...THE MET BEING THE COLD ONE. THIS IN SPITE
OF BOTH MODELS INDICATING SIMILAR SENSIBLE WEATHER (SUNNY..LIGHT
WINDS..UNDER HIGH), AND HAVING ABOUT THE SAME 925 HPA FORECASTED
TEMPS (3-5C)AS WELL. THIS DIFFERENCE IN THE MET/MAV IS REFLECTED
IN THEIR MODEL SOUNDINGS AND PARTICULARLY AROUND MAX TEMP TIME @
18UTC. WHILE THE NEW NAM PHYSICS HAVE GENERALLY BEEN BETTER SINCE
THE UPGRADE SOMETHING SEEMS SQUIRRELLY IN THE MET TEMPS SUNDAY.
TODAY SO FAR WHERES THERE NO SUN TEMPS ARE STILL MID 40S TO AROUND
50...AND WELL INTO THE 50S WHERE THE SUN IS SHINING. COULD JUST
BLEND THE TWO...BUT GIVEN THE COMPARISON TO TODAY..FCST WILL GO
WITH THE MAV TEMPS
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MONDAY INTO MONDAY NIGHT THE LINGERING 500HPA TROF FROM THE MID
ATLC STATES PHASES WITH A TROF LIFTING NE FM GULF COAST STATES. STILL
CONSIDERABLE VARIATION IN THE PHASING AND THE SFC RESPONSE...BUT
GFS/ECMWF AND NAM PRODUCE A COASTAL LOW MONDAY NT THAT LIFTS NE.
THE MDL TRACKS ARE STILL QUITE VARIED. THE GFS/ECMWF KEEP FCA ON
PERIPHERY OF SYSTEM WITH THREAT OF ONLY LT RN IN SE FCA...THE NAM
A BIT MORE AGGRESSIVE WITH QPF AND FURTHER WEST. BOTTOM LINE WILL
INTRODUCE CHC POPS MON NT INTO TUES MAINLY IN SE HALF OF FCA.
ONCE THIS FIRST SYSTEM PASSES THERE`S AS MUCH AGREEMENT AS YOU
USUALLY GET IN THE EFP FOR THE REST OF THE PERIOD. THERE ARE FEW
SIGNIFICANT DIFFERENCES BWTN HPC...THE ECMWF THAT JUST CAME IN AND
THE GFS. WILL POPULATE WITH HPC GRIDS FOR EFP.
IT APPEARS THIS EXTENDED PERIOD WILL BE A GAME CHANGER. AFTER
TUESDAYS WEAK COASTAL DEPARTS A SERIES OF SHORT WAVES PHASE INTO A
DEEP AND LARGE 500HPA CUT OFF OVER THE MISSISSIPPI VALLEY AS
ANOTHER CUTOFF ORGANIZES OVER SOUTH CENTRAL CANADA. THESE SYSTEMS
INTERACT WITH EACH OTHER DURING THE EXTENDED PERIOD CREATING A
DUMBELLING ACTION AROUND EACH OTHER OVER THE GRTLKS..MIDWEST AND
UPR GRT PLAINS FOR MUCH OF THE WEEK TILL THEY PHASE INTO A MASSIVE
CUTOFF LOVER THE EASTERN SEABOARD TO END THE WEEK. THE MAIN STORM
TRACKS WILL PASS TO OUR WEST AT FIRST...WITH THE FINAL ONE A
COASTAL BY THE WEEKEND. THE RESULT WILL BE AN UNSETTLED PERIOD AS
WE HEAD INTO THE THANKSGIVING TRAVEL AND HOLIDAY PERIOD. THERE
WILL BE SEVERAL FRONTAL PASSAGES AND THEIR BOUTS OF PRECIPITATION.
TEMPS WILL REMAIN NR OR ABOVE NORMAL TILL THE END OF THE WEEK WHEN
IT WILL TURN NOTICEABLY COLDER.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE REGION SATURDAY THROUGH
SUNDAY.
MUCH OF THE FORECAST AREA WEST OF THE HUDSON VALLEY WAS COVERED
BY A DECK OF LOW STRATUS THAT WAS 2500-3500 FT ASL...WHICH HAD
RESULTED IN MVFR CIGS AT KALB FOR A WHILE THIS AFTERNOON.
HOWEVER THESE CLOUDS HAVE CLEARED OUT OF MOST OF THE HUDSON
VALLEY AND AT 7PM...00Z...SKIES WERE CLEAR AT KALB...KGFL...AND
KPOU. THERE WAS A SMALL AREA OF LOW CLOUDS EAST OF ALBANY WHICH
HAS RESULTED IN A MVFR CIG AT KPSF...AND AREAS OF IFR CIGS MAY
BE EXPECTD ACROSS THE TACONIC RIDGE EAST OF THE HUDSON VALLEY
AND ALSO OVER HIGHER ELEVS OF THE CATSKILLS AND ADIRONDACKS
WEST OF THE HUDSON VALLEY.
THE CLEARING SKIES...ALONG WITH DIMINISHING WINDS...HAS BROUGHT
ABOUT ANOTHER COMPLICATION...THAT BEING THE POSSIBILITY OF
RADIATION FOG. TEMPERATURES ARE EXPECTED TO DROP THE NEXT FEW
HOURS WITH RADIATIONAL COOLING AND ARE LIKELY TO GET CLOSE TO THE
DEWPOINT RIGHT SHORTLY BEFORE MIDNIGHT. WE HAVE FORECAST MVFR
VISIBILITY AT KGFL STARTING AT 04Z...WITH IFR IN FOG POSSIBLE BY
05Z...AND IFR CIG AND VISBY LIKELY AFTER 08Z. A LIGHT NORTH WIND OFF
THE MOHAWK RIVER WILL PROBABLY RESULT IN MVFR FOG STARTING AROUND
07Z. AT THIS POINT ...WITH A LIGHT NORTHWESTERLY FLOW...WE ARE
EXPECTING KPOU TO REMAIN VFR WITH 6 MILES IN LIGHT FOG.
WINDS AT KALB WILL TURN NORTH AROUND 3 KTS LATER THIS EVENING
AND WILL BE CALM AT KGFL AND KPOU.
FOR SUNDAY...FOG AND LOW CLOUDS WILL BURN OFF AND MIX OUT 1 TO
2 HOURS AFTER SUNRISE. AFTER THAT...A BEAUTIFUL VFR DAY WITH
MOSTLY CLEAR SKIES...AND LIGHT NORTH/NORTHEASTERLY WINDS.
OUTLOOK...
SUN NITE...VFR...NO SIG WX.
MON-TUE...VFR-MVFR...CHC OF RAIN.
WED...VFR...CHC OF SHOWERS.
&&
.HYDROLOGY...
WITH DRY CONDITIONS EXPECTED TO LAST AT LEAST INTO MONDAY RIVERS
WILL CONTINUE RECEDE THROUGH MONDAY. THE NEXT THREAT OF RAIN WILL
BE LATE MONDAY INTO TUESDAY. CONSENSUS OF MODELS IS FOR 0.10 TO
0.70 INCHES MAINLY IN THE SOUTHEAST. BUT ALOT OF UNCERTAINTY
REMAINS WITH THE STORM TRACK AND AMOUNTS COULD VARY. THIS EVENT
SHOULD HAVE MODEST IMPACT ON RIVERS AND STREAMS. FURTHER OUT AN
UNSETTLED PERIOD OF WEATHER THURSDAY INTO THE WEEKEND COULD RESULT
IN SIGNIFICANT PRECIPITATION AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...RCK
NEAR TERM...RCK/NAS
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...RCK
HYDROLOGY...SNYDER
000
FXUS61 KALY 220014
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
705 PM EST SAT NOV 21 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL COVER THE NORTHEAST...SLIDING
OFF INTO CANADIAN MARITIMES LATE MONDAY. CLOUDS OVER THE REGION
WILL DIMINISH WITH GENERALLY CLEAR SKIES SUNDAY INTO MONDAY. OUR
WEATHER WILL TURN UNSETTLED MUCH OF THE UPCOMING WEEK. FIRST A LOW
PRESSURE AREA WILL MOVE NORTHEAST FROM THE CAROLINA COAST MONDAY
NIGHT AND TUESDAY. THEN MIDWEEK A SERIES OF MUCH STRONGER STORMS
WILL MOVE THOUGH THE MIDWEST AND GREAT LAKES.
&&
.NEAR TERM /THROUGH TONIGHT/...
SKIES HAVE CLEARED FROM THE HUDSON VALLEY EASTWARD EXCEPT FOR A
SMALL PATCH OF CLOUDS JUST WEST OF THE NORTHERN TACONICS ALONG
AND JUST WEST OF THE NY/VT/MA STATE LINE. WILL BE MAKING SOME
MINOR CHANGES IN THE GRIDS BUT FOR THE MOST PART THE FORECAST
IS IN GOOD SHAPE. TEMPERATURES WERE MOSTLY IN THE LOW TO MID
40S. LATEST SATELLITE IMAGES SHOW LITTLE CHANGE IN THE AREA
OF CLOUDS THAT COVER UPSTATE NEW YORK WEST OF THE HUDSON
VALLEY ALONG WITH ADJACENT PARTS OF PA...LAKES ONTARIO AND
ERIE...AND SOUTHERN ONTARIO.
***PREVIOUS NEAR TERM...ISSUED AT 245 PM TODAY...***
SURFACE HIGH IN THE GREAT LAKES AND OH VALLEY CONTINUES TO GRADUALLY
BUILD INTO THE REGION. WEST TO NORTHWEST FLOW ACROSS THE LAKES AND
AN INVERSION AT THE BOUNDARY LAYER HAS RESULTED IN WIDESPREAD CLOUD
COVER. HOWEVER...AREAS IN LEE OF THE EASTERN CATSKILLS...BERKSHIRES
AND SOUTHERN GREEN MOUNTAINS HAVE SEEN RELATIVELY LITTLE CLOUD COVER
DUE TO DOWNSLOPE.
RECENT SATELLITE TRENDS ARE CONSISTENT WITH TRENDS SEEN IN
GUIDANCE...WITH CLEARING AND DRYING BEGINNING TO WORK SOUTH FROM
NEAR THE CANADIAN BORDER. THIS CLEARING AND DRYING WILL BUILD SOUTH
THROUGH THE EVENING AND NIGHT...BUT THERE IS SOME QUESTION ABOUT
HOW FAR WEST THE CLEARING WILL GET...DUE TO PROXIMITY TO LAKE
ONTARIO. FOR AREAS AROUND AND EAST OF THE HUDSON VALLEY...CLEARING
SHOULD SPREAD ACROSS THE REGION BY THE EARLY MORNING HOURS. AREAS
OF THE WESTERN MOHAWK VALLEY TO SCHOHARIE VALLEY AND PARTS OF THE
CATSKILLS MAY BE A BIT SLOWER TO CLEAR. STILL...BY SUNRISE...
SUGGESTING ALL AREAS WILL CLEAR. WITH AT LEAST A COUPLE/FEW HOURS
OF CLEARING BEFORE SUNRISE...TEMPERATURES SHOULD FALL TO NEAR
GUIDANCE LEVELS...EVEN THOUGH TEMPERATURES WILL NOT FALL MUCH UNTIL
CLEARING OCCURS.
UPSTREAM SURFACE DEW POINTS NOT TOO DRY...SO LOW TEMPERATURES SHOULD
NOT BE MUCH BELOW GUIDANCE IN AREAS THAT SEE THE LONGEST PERIOD OF
CLEARING...AND MAYBE A BIT ABOVE GUIDANCE WHERE CLEARING IS MOST
DELAYED. MOST TEMPERATURE BUST POTENTIAL TONIGHT LOOKS TO BE IN THE
WESTERN MOHAWK VALLEY...SCHOHARIE VALLEY AND PARTS OF THE
CATSKILLS...WHERE TIMING OF CLEARING IN QUESTION.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
RATHER IMPRESSIVE RIDGE OVER RGN FOR THIS PERIOD AT SFC AND ALOFT.
THE 500HPA SHORT WAVE AXIS (FM W MD TO CAPE COD) WILL BE EXITING
THE RGN AT START OF THE PERIOD AND TAKING WITH IT MOST OF THE
FORCING THAT RESULTED IN THE CLOUDS THAT WERE TRAPPED UNDER THE
INVERSION. WRF ALSO SHOWS DRYING AND DRY AIR ADVECTION JUST PRIOR
TO THIS PERIOD. SO SUNDAY SHOULD BE A SUNNY DAY WITH ABV NORMAL
TEMPS AND ANY RESIDUAL CLOUDS WILL GO QUICKLY.
FOR THE MOST PART WE HAVE MODEL CONSISTENCY (ECMWF/GEM/GFS/NAM)
FOR SYSTEM PLACEMENT AND TIMING THROUGH MONDAY. THE EXCEPTION IS
THE NAM NOW PUSHES THREAT OF RAIN INTO SE FCA LATE MONDAY...ABOUT
3-6 HOURS FASTER THAN REST OF THE CROWD. BUT THE CONSENSUS
REMAINS FOR A PARTLY SUNNY AND DRY DAY IN MOST OF THE AREA WITH
JUST CHC POPS ALONG THE SOUTHERN PERIPHERAL COUNTIES. SO THERE
SHOULD BE LITTLE CHANGE IN THE FORECAST.
THE OTHER DISCONTINUITY IS THE MAV AND MET TEMPS ARE ABOUT 5-10
DEGREES APART SUNDAY...THE MET BEING THE COLD ONE. THIS IN SPITE
OF BOTH MODELS INDICATING SIMILAR SENSIBLE WEATHER (SUNNY..LIGHT
WINDS..UNDER HIGH), AND HAVING ABOUT THE SAME 925 HPA FORECASTED
TEMPS (3-5C)AS WELL. THIS DIFFERENCE IN THE MET/MAV IS REFLECTED
IN THEIR MODEL SOUNDINGS AND PARTICULARLY AROUND MAX TEMP TIME @
18UTC. WHILE THE NEW NAM PHYSICS HAVE GENERALLY BEEN BETTER SINCE
THE UPGRADE SOMETHING SEEMS SQUIRRELLY IN THE MET TEMPS SUNDAY.
TODAY SO FAR WHERES THERE NO SUN TEMPS ARE STILL MID 40S TO AROUND
50...AND WELL INTO THE 50S WHERE THE SUN IS SHINING. COULD JUST
BLEND THE TWO...BUT GIVEN THE COMPARISON TO TODAY..FCST WILL GO
WITH THE MAV TEMPS
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MONDAY INTO MONDAY NIGHT THE LINGERING 500HPA TROF FROM THE MID
ATLC STATES PHASES WITH A TROF LIFTING NE FM GULF COAST STATES. STILL
CONSIDERABLE VARIATION IN THE PHASING AND THE SFC RESPONSE...BUT
GFS/ECMWF AND NAM PRODUCE A COASTAL LOW MONDAY NT THAT LIFTS NE.
THE MDL TRACKS ARE STILL QUITE VARIED. THE GFS/ECMWF KEEP FCA ON
PERIPHERY OF SYSTEM WITH THREAT OF ONLY LT RN IN SE FCA...THE NAM
A BIT MORE AGGRESSIVE WITH QPF AND FURTHER WEST. BOTTOM LINE WILL
INTRODUCE CHC POPS MON NT INTO TUES MAINLY IN SE HALF OF FCA.
ONCE THIS FIRST SYSTEM PASSES THERE`S AS MUCH AGREEMENT AS YOU
USUALLY GET IN THE EFP FOR THE REST OF THE PERIOD. THERE ARE FEW
SIGNIFICANT DIFFERENCES BWTN HPC...THE ECMWF THAT JUST CAME IN AND
THE GFS. WILL POPULATE WITH HPC GRIDS FOR EFP.
IT APPEARS THIS EXTENDED PERIOD WILL BE A GAME CHANGER. AFTER
TUESDAYS WEAK COASTAL DEPARTS A SERIES OF SHORT WAVES PHASE INTO A
DEEP AND LARGE 500HPA CUT OFF OVER THE MISSISSIPPI VALLEY AS
ANOTHER CUTOFF ORGANIZES OVER SOUTH CENTRAL CANADA. THESE SYSTEMS
INTERACT WITH EACH OTHER DURING THE EXTENDED PERIOD CREATING A
DUMBELLING ACTION AROUND EACH OTHER OVER THE GRTLKS..MIDWEST AND
UPR GRT PLAINS FOR MUCH OF THE WEEK TILL THEY PHASE INTO A MASSIVE
CUTOFF LOVER THE EASTERN SEABOARD TO END THE WEEK. THE MAIN STORM
TRACKS WILL PASS TO OUR WEST AT FIRST...WITH THE FINAL ONE A
COASTAL BY THE WEEKEND. THE RESULT WILL BE AN UNSETTLED PERIOD AS
WE HEAD INTO THE THANKSGIVING TRAVEL AND HOLIDAY PERIOD. THERE
WILL BE SEVERAL FRONTAL PASSAGES AND THEIR BOUTS OF PRECIPITATION.
TEMPS WILL REMAIN NR OR ABOVE NORMAL TILL THE END OF THE WEEK WHEN
IT WILL TURN NOTICEABLY COLDER.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE REGION SATURDAY THROUGH
SUNDAY.
MUCH OF THE FORECAST AREA WEST OF THE HUDSON VALLEY WAS COVERED
BY A DECK OF LOW STRATUS THAT WAS 2500-3500 FT ASL...WHICH HAD
RESULTED IN MVFR CIGS AT KALB FOR A WHILE THIS AFTERNOON.
HOWEVER THESE CLOUDS HAVE CLEARED OUT OF MOST OF THE HUDSON
VALLEY AND AT 7PM...00Z...SKIES WERE CLEAR AT KALB...KGFL...AND
KPOU. THERE WAS A SMALL AREA OF LOW CLOUDS EAST OF ALBANY WHICH
HAS RESULTED IN A MVFR CIG AT KPSF...AND AREAS OF IFR CIGS MAY
BE EXPECTD ACROSS THE TACONIC RIDGE EAST OF THE HUDSON VALLEY
AND ALSO OVER HIGHER ELEVS OF THE CATSKILLS AND ADIRONDACKS
WEST OF THE HUDSON VALLEY.
THE CLEARING SKIES...ALONG WITH DIMINISHING WINDS...HAS BROUGHT
ABOUT ANOTHER COMPLICATION...THAT BEING THE POSSIBILITY OF
RADIATION FOG. TEMPERATURES ARE EXPECTED TO DROP THE NEXT FEW
HOURS WITH RADIATIONAL COOLING AND ARE LIKELY TO GET CLOSE TO THE
DEWPOINT RIGHT SHORTLY BEFORE MIDNIGHT. WE HAVE FORECAST MVFR
VISIBILITY AT KGFL STARTING AT 04Z...WITH IFR IN FOG POSSIBLE BY
05Z...AND IFR CIG AND VISBY LIKELY AFTER 08Z. A LIGHT NORTH WIND OFF
THE MOHAWK RIVER WILL PROBABLY RESULT IN MVFR FOG STARTING AROUND
07Z. AT THIS POINT ...WITH A LIGHT NORTHWESTERLY FLOW...WE ARE
EXPECTING KPOU TO REMAIN VFR WITH 6 MILES IN LIGHT FOG.
WINDS AT KALB WILL TURN NORTH AROUND 3 KTS LATER THIS EVENING
AND WILL BE CALM AT KGFL AND KPOU.
FOR SUNDAY...FOG AND LOW CLOUDS WILL BURN OFF AND MIX OUT 1 TO
2 HOURS AFTER SUNRISE. AFTER THAT...A BEAUTIFUL VFR DAY WITH
MOSTLY CLEAR SKIES...AND LIGHT NORTH/NORTHEASTERLY WINDS.
OUTLOOK...
SUN NITE...VFR...NO SIG WX.
MON-TUE...VFR-MVFR...CHC OF RAIN.
WED...VFR...CHC OF SHOWERS.
&&
.HYDROLOGY...
WITH DRY CONDITIONS EXPECTED TO LAST AT LEAST INTO MONDAY RIVERS
WILL CONTINUE RECEDE THROUGH MONDAY. THE NEXT THREAT OF RAIN WILL
BE LATE MONDAY INTO TUESDAY. CONSENSUS OF MODELS IS FOR 0.10 TO
0.70 INCHES MAINLY IN THE SOUTHEAST. BUT ALOT OF UNCERTAINTY
REMAINS WITH THE STORM TRACK AND AMOUNTS COULD VARY. THIS EVENT
SHOULD HAVE MODEST IMPACT ON RIVERS AND STREAMS. FURTHER OUT AN
UNSETTLED PERIOD OF WEATHER THURSDAY INTO THE WEEKEND COULD RESULT
IN SIGNIFICANT PRECIPITATION AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SNYDER
NEAR TERM...NAS
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...RCK
HYDROLOGY...SNYDER
000
FXUS61 KBOX 212352
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
652 PM EST SAT NOV 21 2009
.SYNOPSIS...
HIGH PRESSURE WILL MOVE FROM THE GREAT LAKES INTO SOUTHEAST CANADA
TONIGHT...THEN MOVE EAST OF NOVA SCOTIA MONDAY. LOW PRESSURE WILL
BRING RAIN TO THE REGION LATE MONDAY INTO TUESDAY. WEAK HIGH PRESSURE
WILL TEMPORARILY BUILD INTO THE REGION WEDNESDAY NIGHT AND
THANKSGIVING DAY...BEFORE ANOTHER LOW PRESSURE THREATENS THE REGION
WITH MORE RAIN VERY LATE THANKSGIVING NIGHT AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
SKIES HAVE BECOME CLEAR ACROSS THE VAST MAJORITY OF SOUTHERN NEW
ENGLAND...WITH JUST SOME LEFT OVER HIGH CLOUDS ACROSS THE
CAPE/ISLANDS EARLY THIS EVENING. SKIES SHOULD GENERALLY REMAIN
MOSTLY CLEAR OVERNIGHT WITH LIGHT WINDS. THIS WILL RESULT IN A GOOD
NIGHT OF RADIATIONAL COOLING.
TEMPERATURES ALREADY RUNNING A FEW DEGREES BELOW GUIDANCE VALUES EARLY
THIS EVENING...SO HAVE UNDERCUT GUIDANCE A BIT OVERNIGHT. LOWS
SHOULD FALL WELL DOWN INTO THE 30S ACROSS MOST OF THE REGION...WITH
EVEN SOME UPPER 20S POSSIBLE ACROSS THE NORMALLY COLDEST SPOTS
MAINLY IN SOUTHWEST NH/NORTHWEST MA. THE WARM SPOT SHOULD BE THE
URBAN HEAT ISLAND OF BOSTON WITH LOWS AROUND 40 TO THE LOWER 40S.
ISOLATED PATCHY GROUND FOG WILL LIKELY DEVELOP LATE IN THE TYPICALLY
PRONE LOCATIONS...ESPECIALLY ACROSS SOUTHWEST NH/NORTHWEST MA.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
HIGH PRESSURE REMAINS ACROSS NORTHERN NEW ENGLAND AND SOUTHEAST
CANADA. THIS SHOULD MEAN ANOTHER MOSTLY SUNNY DAY...BUT THIS TIME
WITH ONSHORE WINDS BY AFTERNOON. THESE ONSHORE WINDS COULD LEAD
MARINE STRATUS LATE IN THE DAY INTO SUNDAY NIGHT...PARTICULARLY SOUTH
AND EAST OF I-95 IN MA AND RI. GIVEN THE EXPECTED TIMING OF THE WIND
SHIFT THOUGH...THINKING THIS MAY BE MORE OF A CONCERN SUNDAY NIGHT.
MOS TEMPERATURES LOOK REASONABLE ONCE AGAIN...SO USED A BLEND OF THE
MAV/MET GUIDANCE.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
MONDAY AND TUESDAY...
PLENTY OF UNCERTAINTY REMAINS BUT CONFIDENCE IS GROWING THAT AT
LEAST SOME RAIN WILL AFFECT THE REGION LATER MONDAY INTO TUESDAY.
THE MAIN DILEMMA IS HOW CLOSE TO THE COAST A WAVE OF LOW PRESSURE
TRACKS AND ALSO ITS INTENSITY. HOWEVER...LATEST MODELS ALONG WITH
SREF ENSEMBLES SUGGEST THAT EVEN IF THE SOUTHERN AND WEAKEST
SOLUTIONS VERIFY THERE WILL LIKELY BE AT LEAST SOME RAIN WITH
PERSISTENT ONSHORE FLOW.
THE MAIN QUESTION IS WILL A PERIOD OF HEAVIER RAIN EFFECT PORTIONS
OF THE REGION. THE GEM/NAM CERTAINLY SHOW THIS POTENTIAL...WHILE
THE GFS/UKMET ARE MUCH FURTHER SOUTH SUGGESTING MAINLY
RAIN/DRIZZLE. THE ECMWF IS NOT AS EXTREME AS THE VERY WET GEM/NAM
BUT IT DOES LEAN IN MORE OF THEIR DIRECTION. THEREFORE...WE WILL
LEAN IN THE ECMWF/S DIRECTION FOR NOW ESPECIALLY CONSIDERING ITS
TRACK RECORD IN THIS TIMEFRAME. WILL RUN WITH A PERIOD OF LIKELY POPS
ACROSS THE ENTIRE REGION MONDAY NIGHT/TUESDAY. A PERIOD OF HEAVY
RAIN IS POSSIBLE DEPENDING ON HOW CLOSE TO THE COAST THE WAVE OF LOW
PRESSURE TRACKS. THE BEST CHANCE FOR HEAVY RAIN WILL BE ACROSS THE
SOUTHERN AND EASTERN SECTIONS. IN FACT...LATER SHIFTS MAY HAVE TO
INCREASE POPS INTO CATEGORICAL LEVELS FOR SOME OF THE REGION.
DESPITE PERSISTENT ONSHORE FLOW MONDAY/TUESDAY...ASTRONOMICAL TIDES
ARE LOW AND THE SYSTEM DOES NOT APPEAR INTENSE ENOUGH TO RESULT IN
ANY COASTAL FLOODING. HOWEVER...MINOR BEACH EROSION CERTAINLY IS
POSSIBLE.
AS FOR TEMPERATURES...CONFIDENCE IS HIGH THAT IT WILL BE RATHER COOL
AND RAW DURING THE AFTERNOON. HIGHS MAINLY IN THE UPPER 40S AND THE
LOWER 50S WITH THE ONSHORE FLOW. CONFIDENCE IS ALSO HIGH THAT WHAT
EVER FALLS WILL BE IN THE LIQUID VARIETY. LOW TEMPERATURES SHOULD
REMAIN IN THE 40 TO 45 DEGREE RANGE ACROSS MOST OF THE REGION.
WEDNESDAY...
LOW CONFIDENCE FORECAST OVER THIS TIME...BUT THE STEADIEST
PRECIPITATION WILL LIKELY BE OVER. HOWEVER...WILL CONTINUE WITH THE
CHANCE OF A FEW SHOWERS WITH WAVE OF LOW PRESSURE STILL SPINNING OFF
THE COAST. PRECIPITATION CHANCES MAY DIMINISH LATER WEDNESDAY
AFTERNOON AND EVENING AS DRIER AIR WORKS INTO THE REGION FROM THE
WEST AND THE LOW FINALLY PULLS AWAY. HIGHS SHOULD MAINLY BE IN THE
UPPER 40S TO MID 50S ACROSS THE REGION.
WEDNESDAY NIGHT THROUGH FRIDAY...
ALTHOUGH THE TIMING CAN CERTAINLY CHANGE SINCE WE ARE STILL 5 TO 6
DAYS OUT...AT THIS TIME IT APPEARS THAT MOST OF WEDNESDAY NIGHT
THANKSGIVING DAY MAY TURN OUT DRY. A WEAK RIDGE OF HIGH PRESSURE
LOOKS TO TEMPORARILY BUILD INTO THE REGION WEDNESDAY NIGHT AND
THANKSGIVING DAY.
HOWEVER...A VIGOROUS TROUGH DEVELOPING OVER THE GREAT LAKES MAY
ALLOW ANOTHER LOW PRESSURE SYSTEM TO AFFECT THE REGION LATE
THANKSGIVING NIGHT INTO FRIDAY. AGAIN...TIMING AND FORECASTS ARE
SUBJECT TO SIGNIFICANT ERRORS THIS FAR IN ADVANCE. HOWEVER...THIS MAY
BRING MORE RAIN TO THE REGION. TEMPERATURE PROFILES CONTINUE TO
LOOK TOO WARM SUPPORT ANY FROZEN PRECIPITATION EVEN IN THE DISTANT
INTERIOR FOR MOST OF THE POTENTIAL EVENT.
SATURDAY...
BLUSTERY AND CHILLY WEATHER LOOKS TO BE FILTERED INTO THE REGION
BEHIND THE SYSTEM. MUCH OF THE DAY WILL BE DRY...BUT CAN NOT RULE
OUT A FEW SPRINKLES/PASSING RAIN SHOWER SO WILL RUN WITH A SLIGHT
CHANCE. ITS NOT OUT OF THE QUESTION THAT A FEW WET SNOWFLAKES FALL
ACROSS THE INTERIOR HIGH TERRAIN BUT IT DOES NOT APPEAR TO BE A BIG
DEAL.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
TONIGHT...VFR. THERE IS A LOW PROBABILITY THAT BRIEF MVFR
VISIBILITIES IN PATCHY GROUND FOG COULD AFFECT THE BAF/BDL TERMINALS
FOR A FEW HOURS AFTER MIDNIGHT.
SUNDAY...VFR. MAY SEE PATCHY VFR TO LOCAL MVFR CIGS ALONG THE COAST
DURING THE LATE MORNING AND AFTERNOON.
SUNDAY NIGHT...VFR MOST LOCATIONS. GREATER RISK OF MVFR CIGS ALONG
THE EAST COAST AND SOUTH AND EAST OF A LINE FROM KBOS-KPVD.
CONFIDENCE ON THIS IS NOT HIGH AT THIS TIME.
OUTLOOK /MONDAY THROUGH THURSDAY/...
MONDAY AND TUESDAY...MVFR-IFR CONDITIONS IN LOW CLOUDS AND RAIN WILL
OVERSPREAD THE REGION FROM SOUTH TO NORTH SOMETIME ON MONDAY AND
PERSIST INTO TUESDAY.
WEDNESDAY...LOW CONFIDENCE FORECAST BUT MVFR-IFR CONDITIONS MAY
LINGER IN LOW CLOUDS/RAIN SHOWERS FOR A TIME.
WEDNESDAY NIGHT AND THANKSGIVING...MAINLY VFR BUT CONDITIONS MAY
DETERIORATE LATE THANKSGIVING NIGHT.
&&
.MARINE...
HIGH PRES BUILDING N OF THE WATERS TONIGHT. WINDS GRADUALLY SHIFTING
N TONIGHT...THEN NE SUNDAY INTO SUNDAY NIGHT. SEAS BELOW 5 FT TONIGHT
INTO EARLY SUNDAY. DO EXPECT SEAS TO BUILD OVER 5 FT ACROSS THE OUTER
COASTAL WATERS SUNDAY AFTERNOON INTO SUNDAY NIGHT ONCE NE WINDS GET
ESTABLISHED. THERE IS STILL A QUESTION ABOUT STRENGTH OF THESE
WINDS...WHICH WILL BE ENTIRELY DEPENDENT UPON THE APPROACH OF A LOW
PRESSURE FROM THE MID ATLANTIC COAST. BASED UPON THE BUILDING
SEAS...WILL HOIST A SMALL CRAFT ADVISORY FOR THE OUTER COASTAL
WATERS.
OUTLOOK /MONDAY THROUGH THURSDAY/...
MONDAY THROUGH WEDNESDAY...CANADIAN HIGH PRESSURE WITH LOW PRESSURE
TO THE SOUTH WILL CREATE A PERSISTENT NORTHEAST FLOW AND GOOD
GRADIENT. THIS WILL RESULT IN SCA ACROSS MOST OF OUR WATERS OVER THIS
TIME. SEAS MAY BUILD TO BETWEEN 7 AND 12 FEET ACROSS THE
OUTER-WATERS. THERE IS A LOW PROBABILITY OF A BRIEF MARGINAL GALE
AT SOME POINT.
THANKSGIVING...WINDS SHOULD TEMPORARILY DIMINISH AS WEAK RIDGE OF HIGH
PRESSURE BUILDS IN DURING THE DAY. HOWEVER...SEAS WILL LIKELY
REMAIN ABOVE SCA THRESHOLDS ACROSS THE OUTER-WATERS. WINDS AND SEAS
MAY ONCE AGAIN INCREASE VERY LATE THANKSGIVING NIGHT IN ADVANCE OF
OUR NEXT POSSIBLE SYSTEM
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 9 AM SUNDAY TO 6 AM EST MONDAY FOR
ANZ250-254.
SMALL CRAFT ADVISORY FROM NOON SUNDAY TO 6 AM EST MONDAY FOR
ANZ255.
SMALL CRAFT ADVISORY FROM 3 PM SUNDAY TO 6 AM EST MONDAY FOR
ANZ256.
&&
$$
SYNOPSIS...BELK/FRANK
NEAR TERM...FRANK
SHORT TERM...BELK
LONG TERM...FRANK
AVIATION...BELK/FRANK
MARINE...BELK/FRANK
000
FXUS61 KOKX 212341
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
641 PM EST SAT NOV 21 2009
.SYNOPSIS...
HIGH PRESSURE BUILDS ACROSS EASTERN CANADA...AND INTO THE
MARITIMES THOROUGH MONDAY. AN AREA OF LOW PRESSURE WILL DEVELOP
OFF THE SOUTHEAST US COAST SUNDAY...THEN MOVE UP COAST
MONDAY...PASSING SOUTH AND EAST OF LONG ISLAND THROUGH TUESDAY. WEAK
HIGH PRESSURE BUILDS IN FROM THE NORTH WEDNESDAY. ANOTHER STORM
SYSTEM MAY IMPACT THE TRI- STATE TO CLOSE THE UPCOMING WORK WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
MOSTLY CLEAR SKIES EXPECTED AS WINDS DIMINISH. THIS COMBINATION
WILL RESULT IN DECENT IF NOT IDEAL RADIATIONAL COOLING FOR AT
LEAST A FEW HOURS TONIGHT. FORECAST LOWS...AND DEWPOINTS APPROACH
THE MID 30S IN SPOTS...SO EARLY MORNING FOG IS A POSSIBILITY. THIS
IS NOT IN THE GRIDS AT THIS POINT GIVEN THAT DECOUPLING SHOULD
ONLY LAST A FEW HOURS AS NE WINDS PICK UP A BIT.
UNDERCUT MOS IN GENERAL IN THE NORMALLY COOLER SPOTS ACROSS
ORANGE/PUTNAM COUNTY AND THE PINE BARRENS OF LI. PERSISTENCE AND
MOS VERY CLOSE ELSEWHERE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/...
DEEP LAYER RIDGE PASSES NORTH OF THE CWA SUNDAY...ALLOWING
EASTERLY FLOW ON THE SOUTH SIDE TO INCREASE. ALL IN ALL A DECENT
DAY WITH HIGHS NEAR OR SLIGHTLY BELOW CLIMATOLOGICAL NORMS WITH
EAST WINDS.
TRICKY TEMP FORECAST SUNDAY NIGHT...AS COLD AIR DAMMING AND LOW
LEVEL COLD AIR ADVECTION CONTINUE FROM THE NORTH AND EAST. THERE
MAY AGAIN BE A PERIOD OF DECOUPLING...THUS FORECAST LOW TEMPS ARE
EXPECTED TO END UP CLOSE TO TONIGHT`S. THIS PERIOD IS PERHAPS THE
LOWEST CONFIDENCE TEMP FORECAST OF THE SHORT TERM. IF SURFACE
WINDS STAY UP...AND INCREASING MOISTURE FROM A DEVELOPING SURFACE
LOW GET HERE EARLIER THAN EXPECTED...LOWS WILL BE MUCH WARMER THAN
FORECAST.
MODEL SOLUTIONS STILL DIVERGE ON THE TRACK AND INTENSITY OF A
DIFFUSE COASTAL LOW...BUT THE WIND FIELDS ARE BIT MORE ALIGNED.
PRECIP EXPECTED TO HOLD OFF UNTIL MONDAY NIGHT...ALTHOUGH A BRIEF
PERIOD OF LIGHT OVERRUNNING RAIN POSSIBLE MONDAY AFTERNOON.
INCREASED POP TO LIKELY FOR ABOUT THE EASTERN TWO THIRDS OF THE
CWA TUESDAY MORNING...BUT THIS ULTIMATELY DEPENDS ON IF THE LOW
CENTER PASSES CLOSE ENOUGH TO PUT THE AREA IN THE BEST LIFT. THE
NAM CONTINUES TO BE THE MOST ROBUST IN TERMS OF QPF...BUT THE 18Z
RUN HAS BACKED OFF FROM ITS 1 TO 1.5 INCH FORECAST EARLIER TODAY.
LIGHT RAIN...PRIMARILY WRAP AROUND...POSSIBLE INTO TUESDAY NIGHT.
NOT A WHOLE LOT OF TEMP VARIATION MONDAY NIGHT THROUGH TUESDAY
NIGHT...ESPECIALLY NEAR THE COAST.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
LOW PRES DEPARTS THE REGION TUE NGT WITH CHC POPS FOR -RA ENDING.
SW FLOW ALOFT DEVELOPS WED AS H5 LOW DROPS INTO THE OH VALLEY. H3
JET PRODUCES SOME LIFT...BUT FORCING OTHERWISE IS WEAK AS
EVIDENCED BY THE TIME HEIGHTS. WITH MRGNL MOISTURE...ONLY LGT PCPN
EXPECTED ATTM. A LULL SETTLES IN WED NGT INTO THU...THEN THE FOCUS
SHIFTS TO LATE THU AND FRI. ANOTHER H5 LOW DROPS INTO THE OH
VALLEY WITH A COMPLEX REFLECTION AT THE SFC. MODELS HINT AT LOW
PRES DEVELOPING ALONG THE NRN GULF COAST AND TRACKING NEWD OFF THE
ATLANTIC COAST...WITH A SECOND LOW DEVELOPING OVER THE ERN GREAT
LAKES. ALTHO THERE IS A SPREAD IN THE MODEL SOLNS...IT APPEARS A
SHOT OF RA ON TRACK DURING THE PERIOD. MAIN ISSUE MAY TURN OUT TO
BE THE WIND IF THE 12Z GFS/ECMWF SOLNS ARE CLOSE AND A 980S LOW
OCCLUDES OVER NRN NEW ENGLAND SAT MRNG.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
WINDS INITIALLY AROUND 10 KTS AT A FEW LOCALES IN AND AROUND NYC
METRO THIS EVENING. OTHERWISE...NW FLOW UNDER 10 KT SHOULD VEER N
OVERNIGHT. WINDS THEN TURN NE WITH SPEEDS INCREASING TO AROUND 10
KT...HIGHER AT NYC/COASTAL TERMINALS...TOWARD OR JUST AFTER
DAYBREAK SUNDAY MORNING AS HIGH PRESSURE OVER THE THE OH VALLEY
BUILDS NE INTO NEW ENGLAND. RADIATION FOG WITH MVFR CONDITIONS MAY
OCCUR...ALTHOUGH CONFIDENCE IN THIS HAPPENING IS LOW...LATE
TONIGHT AT KSWF AND KGON. WILL HAVE TO MONITOR OTHER TERMINALS
OUTSIDE THE NYC URBAN HEAT ISLAND FOR THIS POSSIBILITY CLOSE
TO/JUST AFTER SUNRISE.
VFR THROUGH THE DAY SUNDAY WITH NE WINDS 9 TO 12 KTS.
OUTLOOK 00Z MONDAY THROUGH THU...
SUNDAY NIGHT...VFR.
MON...SUB-VFR POSSIBLE.
MON NIGHT-TUE...SUB-VFR LIKELY.
TUE NIGHT-WED...BECOMING VFR.
THU...SUB-VFR POSSIBLE.
&&
.MARINE...
NORTHERLY FLOW BECOMES NORTHEAST OVERNIGHT...AS HIGH PRESSURE
SETTLES INTO EASTERN CANADA. THE PRESSURE GRADIENT STRENGTHENS
THROUGH SUNDAY EVENING WITH LOWERING PRESSURE TO THE SOUTH. SMALL
CRAFT CONDITIONS EXPECTED TO BEGIN ON OCEAN WATERS SUNDAY EVENING.
EXPECT WINDS TO INCREASE FROM SOUTH TO NORTH...AND IT IS POSSIBLE
THE THE WATERS RIGHT ALONG THE COAST OF LONG ISLAND WILL NOT SEE
25 KTS UNTIL MONDAY MORNING.
SMALL CRAFT WIND CONDITIONS...WITH A FEW GUSTS POSSIBLY
APPROACHING GALE FORCE MONDAY THROUGH TUESDAY.
SCA SEAS ON THE OCEAN LINGER TUE NGT INTO WED...THEN BEGIN TO
SUBSIDE AS LOW PRES WEAKENS N OF THE COASTAL WATERS. A COMPLEX LOW
PRES SYSTEM WILL THEN IMPACT THE WATERS LATE THU INTO FRI. DEPENDING
ON THE EXACT TRACK AND INTENSITY OF THE SYSTEM...GALES MAY BE
POSSIBLE DURING THE PERIOD.
&&
.HYDROLOGY...
DRY THROUGH MONDAY MORNING. A QUARTER TO A HALF AN INCH OF
RAINFALL IS POSSIBLE MONDAY AFTERNOON THROUGH WEDNESDAY. MORE
PRECIPITATION IS EXPECTED TOWARDS THE END OF NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM SUNDAY TO 6 PM EST MONDAY FOR
ANZ350-353-355.
&&
$$
SYNOPSIS...BS
NEAR TERM...BS/PW
SHORT TERM...BS
LONG TERM...JMC
AVIATION...PW
MARINE...BG/JMC
HYDROLOGY...BS
000
FXUS61 KOKX 212116
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
416 PM EST SAT NOV 21 2009
.SYNOPSIS...
HIGH PRESSURE BUILDS ACROSS EASTERN CANADA...AND INTO THE
MARITIMES THOROUGH MONDAY. AN AREA OF LOW PRESSURE WILL DEVELOP
OFF THE SOUTHEAST US COAST SUNDAY...THEN MOVE UP COAST
MONDAY...PASSING SOUTH AND EAST OF LONG ISLAND THROUGH TUESDAY. WEAK HIGH
PRESSURE BUILDS IN FROM THE NORTH WEDNESDAY. ANOTHER STORM SYSTEM
MAY IMPACT THE TRI- STATE TO CLOSE THE UPCOMING WORK WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
MOSTLY SUNNY THIS AFTERNOON. SOLID SC/ST WEST OF THE CWA IS DRYING
SHARPLY DUE TO DOWNSLOPING OFF HIGHER TERRAIN. DECENT RADIATIONAL
COOLING FOR AT LEAST A FEW HOURS TONIGHT. FORECAST LOWS...AND
DEWPOINTS APPROACH THE MID 30S IN SPOTS...SO EARLY MORNING FOG IS
A POSSIBILITY. THIS IS NOT IN THE GRIDS AT THIS POINT GIVEN THAT
DECOUPLING SHOULD ONLY LAST A FEW HOURS AS NE WINDS PICK UP A BIT.
UNDERCUT MOS IN GENERAL IN THE NORMALLY COOLER SPOTS ACROSS
ORANGE/PUTNAM COUNTY AND THE PINE BARRENS OF LI. PERSISTENCE AND
MOS VERY CLOSE ELSEWHERE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/... DEEP LAYER
RIDGE PASSES NORTH OF THE CWA SUNDAY...ALLOWING EASTERLY FLOW ON
THE SOUTH SIDE TO INCREASE. ALL IN ALL A DECENT DAY WITH HIGHS
NEAR OR SLIGHTLY BELOW CLIMATOLOGICAL NORMS WITH EAST WINDS.
TRICKY TEMP FORECAST SUNDAY NIGHT...AS COLD AIR DAMMING AND LOW
LEVEL COLD AIR ADVECTION CONTINUE FROM THE NORTH AND EAST. THERE
MAY AGAIN BE A PERIOD OF DECOUPLING...THUS FORECAST LOW TEMPS ARE
EXPECTED TO END UP CLOSE TO TONIGHT`S. THIS PERIOD IS PERHAPS THE
LOWEST CONFIDENCE TEMP FORECAST OF THE SHORT TERM. IF SURFACE
WINDS STAY UP...AND INCREASING MOISTURE FROM A DEVELOPING SURFACE
LOW GET HERE EARLIER THAN EXPECTED...LOWS WILL BE MUCH WARMER THAN
FORECAST.
MODEL SOLUTIONS STILL DIVERGE ON THE TRACK AND INTENSITY OF A
DIFFUSE COASTAL LOW...BUT THE WIND FIELDS ARE BIT MORE ALIGNED.
PRECIP EXPECTED TO HOLD OFF UNTIL MONDAY NIGHT...ALTHOUGH A BRIEF
PERIOD OF LIGHT OVERRUNNING RAIN POSSIBLE MONDAY AFTERNOON.
INCREASED POP TO LIKELY FOR ABOUT THE EASTERN TWO THIRDS OF THE
CWA TUESDAY MORNING...BUT THIS ULTIMATELY DEPENDS ON IF THE LOW
CENTER PASSES CLOSE ENOUGH TO PUT THE AREA IN THE BEST LIFT. THE
NAM CONTINUES TO BE THE MOST ROBUST IN TERMS OF QPF...BUT THE 18Z
RUN HAS BACKED OFF FROM ITS 1 TO 1.5 INCH FORECAST EARLIER TODAY.
LIGHT RAIN...PRIMARILY WRAP AROUND...POSSIBLE INTO TUESDAY NIGHT.
NOT A WHOLE LOT OF TEMP VARIATION MONDAY NIGHT THROUGH TUESDAY
NIGHT...ESPECIALLY NEAR THE COAST.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... LOW PRES DEPARTS
THE REGION TUE NGT WITH CHC POPS FOR -RA ENDING. SW FLOW ALOFT
DEVELOPS WED AS H5 LOW DROPS INTO THE OH VALLEY. H3 JET PRODUCES
SOME LIFT...BUT FORCING OTHERWISE IS WEAK AS EVIDENCED BY THE TIME
HEIGHTS. WITH MRGNL MOISTURE...ONLY LGT PCPN EXPECTED ATTM. A LULL
SETTLES IN WED NGT INTO THU...THEN THE FOCUS SHIFTS TO LATE THU
AND FRI. ANOTHER H5 LOW DROPS INTO THE OH VALLEY WITH A COMPLEX
REFLECTION AT THE SFC. MODELS HINT AT LOW PRES DEVELOPING ALONG
THE NRN GULF COAST AND TRACKING NEWD OFF THE ATLANTIC COAST...WITH
A SECOND LOW DEVELOPING OVER THE ERN GREAT LAKES. ALTHO THERE IS A
SPREAD IN THE MODEL SOLNS...IT APPEARS A SHOT OF RA ON TRACK
DURING THE PERIOD. MAIN ISSUE MAY TURN OUT TO BE THE WIND IF THE
12Z GFS/ECMWF SOLNS ARE CLOSE AND A 980S LOW OCCLUDES OVER NRN NEW
ENGLAND SAT MRNG.
&&
.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
NW FLOW UNDER 10 KT SHOULD VEER N TONIGHT...AND THEN NE WITH SPEEDS
INCREASING TO AROUND 10 KT...HIGHER AT NYC/COASTAL TERMINALS...
TOWARD OR JUST AFTER DAYBREAK SUNDAY MORNING AS HIGH PRESSURE OVER
THE THE OH VALLEY BUILDS NE INTO NEW ENGLAND. RADIATION FOG WITH
MVFR CONDITIONS MAY IS LIKELY LATE TONIGHT AT KSWF AND KGON...AND
WILL HAVE TO MONITOR OTHER TERMINALS OUTSIDE THE NYC URBAN HEAT
ISLAND FOR THIS POSSIBILITY CLOSE TO/JUST AFTER SUNRISE.
OUTLOOK 18Z SUNDAY THROUGH THU...
SUNDAY AFTERNOON/NIGHT...VFR.
MON...SUB-VFR POSSIBLE.
MON NIGHT-TUE...SUB-VFR LIKELY.
TUE NIGHT-WED...BECOMING VFR.
THU...SUB-VFR POSSIBLE.
&&
.MARINE...
LIGHT NORTHERLY FLOW BECOMES NORTHEAST OVERNIGHT...AS HIGH
PRESSURE SETTLES INTO EASTERN CANADA. THE PRESSURE GRADIENT
STRENGTHENS THROUGH SUNDAY EVENING WITH LOWERING PRESSURE TO THE
SOUTH. SMALL CRAFT CONDITIONS EXPECTED TO BEGIN ON OCEAN WATERS
SUNDAY EVENING. EXPECT WINDS TO INCREASE FROM SOUTH TO NORTH...AND
IT IS POSSIBLE THE THE WATERS RIGHT ALONG THE COAST OF LONG ISLAND
WILL NOT SEE 25 KTS UNTIL MONDAY MORNING.
SMALL CRAFT WIND CONDITIONS...WITH A FEW GUSTS POSSIBLY
APPROACHING GALE FORCE MONDAY THROUGH TUESDAY.
SCA SEAS ON THE OCEAN LINGER TUE NGT INTO WED...THEN BEGIN TO
SUBSIDE AS LOW PRES WEAKENS N OF THE COASTAL WATERS. A COMPLEX LOW
PRES SYSTEM WILL THEN IMPACT THE WATERS LATE THU INTO FRI. DEPENDING
ON THE EXACT TRACK AND INTENSITY OF THE SYSTEM...GALES MAY BE
POSSIBLE DURING THE PERIOD.
&&
.HYDROLOGY...
DRY THROUGH MONDAY MORNING. A QUARTER TO A HALF AN INCH OF
RAINFALL IS POSSIBLE MONDAY AFTERNOON THROUGH WEDNESDAY. MORE
PRECIPITATION IS EXPECTED TOWARDS THE END OF NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM SUNDAY TO 6 PM EST MONDAY FOR
ANZ350-353-355.
&&
$$
SYNOPSIS...BS
NEAR TERM...BS
SHORT TERM...BS
LONG TERM...JMC
AVIATION...BG
MARINE...BG/JMC
HYDROLOGY...BS
000
FXUS61 KBOX 212027
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
327 PM EST SAT NOV 21 2009
.SYNOPSIS...
HIGH PRESSURE WILL MOVE FROM THE GREAT LAKES INTO SOUTHEAST CANADA
TONIGHT...THEN MOVE EAST OF NOVA SCOTIA MONDAY. LOW PRESSURE WILL
BRING RAIN TO THE REGION LATE MONDAY INTO TUESDAY. WEAK HIGH PRESSURE
WILL TEMPORARILY BUILD INTO THE REGION WEDNESDAY NIGHT AND
THANKSGIVING DAY...BEFORE ANOTHER LOW PRESSURE THREATENS THE REGION
WITH MORE RAIN VERY LATE THANKSGIVING NIGHT AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
HIGH CLOUDS CONTINUE TO STREAM ACROSS SOUTHERN NEW ENGLAND...WITH
THE THICKEST CLOUDS NOW ACROSS CAPE COD AND THE ISLANDS. FARTHER
WEST...PLENTY OF CLOUDS FROM THE GREAT LAKES BANKED UP AGAINST THE
WEST SLOPES OF THE BERKSHIRES. WITH WINDS SHIFTING TO THE NORTH AND
REMAINING FAIRLY LIGHT...DO NOT EXPECT THESE CLOUDS TO SPILL OVER THE
BERKSHIRES INTO SOUTHERN NEW ENGLAND.
USED A BLEND OF MOS GUIDANCE FOR TEMPERATURES TONIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
HIGH PRESSURE REMAINS ACROSS NORTHERN NEW ENGLAND AND SOUTHEAST
CANADA. THIS SHOULD MEAN ANOTHER MOSTLY SUNNY DAY...BUT THIS TIME
WITH ONSHORE WINDS BY AFTERNOON. THESE ONSHORE WINDS COULD LEAD
MARINE STRATUS LATE IN THE DAY INTO SUNDAY NIGHT...PARTICULARLY SOUTH
AND EAST OF I-95 IN MA AND RI. GIVEN THE EXPECTED TIMING OF THE WIND
SHIFT THOUGH...THINKING THIS MAY BE MORE OF A CONCERN SUNDAY NIGHT.
MOS TEMPERATURES LOOK REASONABLE ONCE AGAIN...SO USED A BLEND OF THE
MAV/MET GUIDANCE.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
MONDAY AND TUESDAY...
PLENTY OF UNCERTAINTY REMAINS BUT CONFIDENCE IS GROWING THAT AT
LEAST SOME RAIN WILL AFFECT THE REGION LATER MONDAY INTO TUESDAY.
THE MAIN DILEMMA IS HOW CLOSE TO THE COAST A WAVE OF LOW PRESSURE
TRACKS AND ALSO ITS INTENSITY. HOWEVER...LATEST MODELS ALONG WITH
SREF ENSEMBLES SUGGEST THAT EVEN IF THE SOUTHERN AND WEAKEST
SOLUTIONS VERIFY THERE WILL LIKELY BE AT LEAST SOME RAIN WITH
PERSISTENT ONSHORE FLOW.
THE MAIN QUESTION IS WILL A PERIOD OF HEAVIER RAIN EFFECT PORTIONS
OF THE REGION. THE GEM/NAM CERTAINLY SHOW THIS POTENTIAL...WHILE
THE GFS/UKMET ARE MUCH FURTHER SOUTH SUGGESTING MAINLY
RAIN/DRIZZLE. THE ECMWF IS NOT AS EXTREME AS THE VERY WET GEM/NAM
BUT IT DOES LEAN IN MORE OF THEIR DIRECTION. THEREFORE...WE WILL
LEAN IN THE ECMWF/S DIRECTION FOR NOW ESPECIALLY CONSIDERING ITS
TRACK RECORD IN THIS TIMEFRAME. WILL RUN WITH A PERIOD OF LIKELY POPS
ACROSS THE ENTIRE REGION MONDAY NIGHT/TUESDAY. A PERIOD OF HEAVY
RAIN IS POSSIBLE DEPENDING ON HOW CLOSE TO THE COAST THE WAVE OF LOW
PRESSURE TRACKS. THE BEST CHANCE FOR HEAVY RAIN WILL BE ACROSS THE
SOUTHERN AND EASTERN SECTIONS. IN FACT...LATER SHIFTS MAY HAVE TO
INCREASE POPS INTO CATEGORICAL LEVELS FOR SOME OF THE REGION.
DESPITE PERSISTENT ONSHORE FLOW MONDAY/TUESDAY...ASTRONOMICAL TIDES
ARE LOW AND THE SYSTEM DOES NOT APPEAR INTENSE ENOUGH TO RESULT IN
ANY COASTAL FLOODING. HOWEVER...MINOR BEACH EROSION CERTAINLY IS
POSSIBLE.
AS FOR TEMPERATURES...CONFIDENCE IS HIGH THAT IT WILL BE RATHER COOL
AND RAW DURING THE AFTERNOON. HIGHS MAINLY IN THE UPPER 40S AND THE
LOWER 50S WITH THE ONSHORE FLOW. CONFIDENCE IS ALSO HIGH THAT WHAT
EVER FALLS WILL BE IN THE LIQUID VARIETY. LOW TEMPERATURES SHOULD
REMAIN IN THE 40 TO 45 DEGREE RANGE ACROSS MOST OF THE REGION.
WEDNESDAY...
LOW CONFIDENCE FORECAST OVER THIS TIME...BUT THE STEADIEST
PRECIPITATION WILL LIKELY BE OVER. HOWEVER...WILL CONTINUE WITH THE
CHANCE OF A FEW SHOWERS WITH WAVE OF LOW PRESSURE STILL SPINNING OFF
THE COAST. PRECIPITATION CHANCES MAY DIMINISH LATER WEDNESDAY
AFTERNOON AND EVENING AS DRIER AIR WORKS INTO THE REGION FROM THE
WEST AND THE LOW FINALLY PULLS AWAY. HIGHS SHOULD MAINLY BE IN THE
UPPER 40S TO MID 50S ACROSS THE REGION.
WEDNESDAY NIGHT THROUGH FRIDAY...
ALTHOUGH THE TIMING CAN CERTAINLY CHANGE SINCE WE ARE STILL 5 TO 6
DAYS OUT...AT THIS TIME IT APPEARS THAT MOST OF WEDNESDAY NIGHT
THANKSGIVING DAY MAY TURN OUT DRY. A WEAK RIDGE OF HIGH PRESSURE
LOOKS TO TEMPORARILY BUILD INTO THE REGION WEDNESDAY NIGHT AND
THANKSGIVING DAY.
HOWEVER...A VIGOROUS TROUGH DEVELOPING OVER THE GREAT LAKES MAY
ALLOW ANOTHER LOW PRESSURE SYSTEM TO AFFECT THE REGION LATE
THANKSGIVING NIGHT INTO FRIDAY. AGAIN...TIMING AND FORECASTS ARE
SUBJECT TO SIGNIFICANT ERRORS THIS FAR IN ADVANCE. HOWEVER...THIS MAY
BRING MORE RAIN TO THE REGION. TEMPERATURE PROFILES CONTINUE TO
LOOK TOO WARM SUPPORT ANY FROZEN PRECIPITATION EVEN IN THE DISTANT
INTERIOR FOR MOST OF THE POTENTIAL EVENT.
SATURDAY...
BLUSTERY AND CHILLY WEATHER LOOKS TO BE FILTERED INTO THE REGION
BEHIND THE SYSTEM. MUCH OF THE DAY WILL BE DRY...BUT CAN NOT RULE
OUT A FEW SPRINKLES/PASSING RAIN SHOWER SO WILL RUN WITH A SLIGHT
CHANCE. ITS NOT OUT OF THE QUESTION THAT A FEW WET SNOWFLAKES FALL
ACROSS THE INTERIOR HIGH TERRAIN BUT IT DOES NOT APPEAR TO BE A BIG
DEAL.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
TONIGHT...VFR. PATCHY FOG WITH BRIEF MVFR CIGS/VSBYS LATE AT NIGHT
IN THE NORMALLY SUSCEPTIBLE VALLEYS.
SUNDAY...VFR. MAY SEE PATCHY VFR TO LOCAL MVFR CIGS ALONG THE COAST
DURING THE LATE MORNING AND AFTERNOON.
SUNDAY NIGHT...VFR MOST LOCATIONS. GREATER RISK OF MVFR CIGS ALONG
THE EAST COAST AND SOUTH AND EAST OF A LINE FROM KBOS-KPVD.
CONFIDENCE ON THIS IS NOT HIGH AT THIS TIME.
OUTLOOK /MONDAY THROUGH THURSDAY/...
MONDAY AND TUESDAY...MVFR-IFR CONDITIONS IN LOW CLOUDS AND RAIN WILL
OVERSPREAD THE REGION FROM SOUTH TO NORTH SOMETIME ON MONDAY AND
PERSIST INTO TUESDAY.
WEDNESDAY...LOW CONFIDENCE FORECAST BUT MVFR-IFR CONDITIONS MAY
LINGER IN LOW CLOUDS/RAIN SHOWERS FOR A TIME.
WEDNESDAY NIGHT AND THANKSGIVING...MAINLY VFR BUT CONDITIONS MAY
DETERIORATE LATE THANKSGIVING NIGHT.
&&
.MARINE...
HIGH PRES BUILDING N OF THE WATERS TONIGHT. WINDS GRADUALLY SHIFTING
N TONIGHT...THEN NE SUNDAY INTO SUNDAY NIGHT. SEAS BELOW 5 FT TONIGHT
INTO EARLY SUNDAY. DO EXPECT SEAS TO BUILD OVER 5 FT ACROSS THE OUTER
COASTAL WATERS SUNDAY AFTERNOON INTO SUNDAY NIGHT ONCE NE WINDS GET
ESTABLISHED. THERE IS STILL A QUESTION ABOUT STRENGTH OF THESE
WINDS...WHICH WILL BE ENTIRELY DEPENDENT UPON THE APPROACH OF A LOW
PRESSURE FROM THE MID ATLANTIC COAST. BASED UPON THE BUILDING
SEAS...WILL HOIST A SMALL CRAFT ADVISORY FOR THE OUTER COASTAL
WATERS.
OUTLOOK /MONDAY THROUGH THURSDAY/...
MONDAY THROUGH WEDNESDAY...CANADIAN HIGH PRESSURE WITH LOW PRESSURE
TO THE SOUTH WILL CREATE A PERSISTENT NORTHEAST FLOW AND GOOD
GRADIENT. THIS WILL RESULT IN SCA ACROSS MOST OF OUR WATERS OVER THIS
TIME. SEAS MAY BUILD TO BETWEEN 7 AND 12 FEET ACROSS THE
OUTER-WATERS. THERE IS A LOW PROBABILITY OF A BRIEF MARGINAL GALE
AT SOME POINT.
THANKSGIVING...WINDS SHOULD TEMPORARILY DIMINISH AS WEAK RIDGE OF HIGH
PRESSURE BUILDS IN DURING THE DAY. HOWEVER...SEAS WILL LIKELY
REMAIN ABOVE SCA THRESHOLDS ACROSS THE OUTER-WATERS. WINDS AND SEAS
MAY ONCE AGAIN INCREASE VERY LATE THANKSGIVING NIGHT IN ADVANCE OF
OUR NEXT POSSIBLE SYSTEM
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 9 AM SUNDAY TO 6 AM EST MONDAY FOR
ANZ250-254.
SMALL CRAFT ADVISORY FROM NOON SUNDAY TO 6 AM EST MONDAY FOR
ANZ255.
SMALL CRAFT ADVISORY FROM 3 PM SUNDAY TO 6 AM EST MONDAY FOR
ANZ256.
&&
$$
SYNOPSIS...BELK/FRANK
NEAR TERM...BELK
SHORT TERM...BELK
LONG TERM...FRANK
AVIATION...BELK/FRANK
MARINE...BELK/FRANK
000
FXUS61 KALY 211946
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
246 PM EST SAT NOV 21 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL COVER THE NORTHEAST...SLIDING
OFF INTO CANADIAN MARITIMES LATE MONDAY. CLOUDS OVER THE REGION
WILL DIMINISH WITH GENERALLY CLEAR SKIES SUNDAY INTO MONDAY. OUR
WEATHER WILL TURN UNSETTLED MUCH OF THE UPCOMING WEEK. FIRST A LOW
PRESSURE AREA WILL MOVE NORTHEAST FROM THE CAROLINA COAST MONDAY
NIGHT AND TUESDAY. THEN MIDWEEK A SERIES OF MUCH STRONGER STORMS
WILL MOVE THOUGH THE MIDWEST AND GREAT LAKES.
&&
.NEAR TERM /THROUGH TONIGHT/...
SURFACE HIGH IN THE GREAT LAKES AND OH VALLEY CONTINUES TO
GRADUALLY BUILD INTO THE REGION. WEST TO NORTHWEST FLOW ACROSS THE
LAKES AND AN INVERSION AT THE BOUNDARY LAYER HAS RESULTED IN
WIDESPREAD CLOUD COVER. HOWEVER...AREAS IN LEE OF THE EASTERN
CATSKILLS...BERKSHIRES AND SOUTHERN GREEN MOUNTAINS HAVE SEEN
RELATIVELY LITTLE CLOUD COVER DUE TO DOWNSLOPE.
RECENT SATELLITE TRENDS ARE CONSISTENT WITH TRENDS SEEN IN
GUIDANCE...WITH CLEARING AND DRYING BEGINNING TO WORK SOUTH FROM
NEAR THE CANADIAN BORDER. THIS CLEARING AND DRYING WILL BUILD SOUTH
THROUGH THE EVENING AND NIGHT...BUT THERE IS SOME QUESTION ABOUT
HOW FAR WEST THE CLEARING WILL GET...DUE TO PROXIMITY TO LAKE
ONTARIO. FOR AREAS AROUND AND EAST OF THE HUDSON VALLEY...CLEARING
SHOULD SPREAD ACROSS THE REGION BY THE EARLY MORNING HOURS. AREAS
OF THE WESTERN MOHAWK VALLEY TO SCHOHARIE VALLEY AND PARTS OF THE
CATSKILLS MAY BE A BIT SLOWER TO CLEAR. STILL...BY SUNRISE...
SUGGESTING ALL AREAS WILL CLEAR. WITH AT LEAST A COUPLE/FEW HOURS
OF CLEARING BEFORE SUNRISE...TEMPERATURES SHOULD FALL TO NEAR
GUIDANCE LEVELS...EVEN THOUGH TEMPERATURES WILL NOT FALL MUCH UNTIL
CLEARING OCCURS.
UPSTREAM SURFACE DEW POINTS NOT TOO DRY...SO LOW TEMPERATURES SHOULD
NOT BE MUCH BELOW GUIDANCE IN AREAS THAT SEE THE LONGEST PERIOD OF
CLEARING...AND MAYBE A BIT ABOVE GUIDANCE WHERE CLEARING IS MOST
DELAYED. MOST TEMPERATURE BUST POTENTIAL TONIGHT LOOKS TO BE IN THE
WESTERN MOHAWK VALLEY...SCHOHARIE VALLEY AND PARTS OF THE
CATSKILLS...WHERE TIMING OF CLEARING IN QUESTION.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
RATHER IMPRESSIVE RIDGE OVER RGN FOR THIS PERIOD AT SFC AND ALOFT.
THE 500HPA SHORT WAVE AXIS (FM W MD TO CAPE COD) WILL BE EXITING
THE RGN AT START OF THE PERIOD AND TAKING WITH IT MOST OF THE
FORCING THAT RESULTED IN THE CLOUDS THAT WERE TRAPPED UNDER THE
INVERSION. WRF ALSO SHOWS DRYING AND DRY AIR ADVECTION JUST PRIOR
TO THIS PERIOD. SO SUNDAY SHOULD BE A SUNNY DAY WITH ABV NORMAL
TEMPS AND ANY RESIDUAL CLOUDS WILL GO QUICKLY.
FOR THE MOST PART WE HAVE MODEL CONSISTENCY (ECMWF/GEM/GFS/NAM)
FOR SYSTEM PLACEMENT AND TIMING THROUGH MONDAY. THE EXCEPTION IS
THE NAM NOW PUSHES THREAT OF RAIN INTO SE FCA LATE MONDAY...ABOUT
3-6 HOURS FASTER THAN REST OF THE CROWD. BUT THE CONSENSUS
REMAINS FOR A PARTLY SUNNY AND DRY DAY IN MOST OF THE AREA WITH
JUST CHC POPS ALONG THE SOUTHERN PERIPHERAL COUNTIES. SO THERE
SHOULD BE LITTLE CHANGE IN THE FORECAST.
THE OTHER DISCONTINUITY IS THE MAV AND MET TEMPS ARE ABOUT 5-10
DEGREES APART SUNDAY...THE MET BEING THE COLD ONE. THIS IN SPITE
OF BOTH MODELS INDICATING SIMILAR SENSIBLE WEATHER (SUNNY..LIGHT
WINDS..UNDER HIGH), AND HAVING ABOUT THE SAME 925 HPA FORECASTED
TEMPS (3-5C)AS WELL. THIS DIFFERENCE IN THE MET/MAV IS REFLECTED
IN THEIR MODEL SOUNDINGS AND PARTICULARLY AROUND MAX TEMP TIME @
18UTC. WHILE THE NEW NAM PHYSICS HAVE GENERALLY BEEN BETTER SINCE
THE UPGRADE SOMETHING SEEMS SQUIRRELLY IN THE MET TEMPS SUNDAY.
TODAY SO FAR WHERES THERE NO SUN TEMPS ARE STILL MID 40S TO AROUND
50...AND WELL INTO THE 50S WHERE THE SUN IS SHINING. COULD JUST
BLEND THE TWO...BUT GIVEN THE COMPARISON TO TODAY..FCST WILL GO
WITH THE MAV TEMPS
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MONDAY INTO MONDAY NIGHT THE LINGERING 500HPA TROF FROM THE MID
ATLC STATES PHASES WITH A TROF LIFTING NE FM GULF COAST STATES. STILL
CONSIDERABLE VARIATION IN THE PHASING AND THE SFC RESPONSE...BUT
GFS/ECMWF AND NAM PRODUCE A COASTAL LOW MONDAY NT THAT LIFTS NE.
THE MDL TRACKS ARE STILL QUITE VARIED. THE GFS/ECMWF KEEP FCA ON
PERIPHERY OF SYSTEM WITH THREAT OF ONLY LT RN IN SE FCA...THE NAM
A BIT MORE AGGRESSIVE WITH QPF AND FURTHER WEST. BOTTOM LINE WILL
INTRODUCE CHC POPS MON NT INTO TUES MAINLY IN SE HALF OF FCA.
ONCE THIS FIRST SYSTEM PASSES THERE`S AS MUCH AGREEMENT AS YOU
USUALLY GET IN THE EFP FOR THE REST OF THE PERIOD. THERE ARE FEW
SIGNIFICANT DIFFERENCES BWTN HPC...THE ECMWF THAT JUST CAME IN AND
THE GFS. WILL POPULATE WITH HPC GRIDS FOR EFP.
IT APPEARS THIS EXTENDED PERIOD WILL BE A GAME CHANGER. AFTER
TUESDAYS WEAK COASTAL DEPARTS A SERIES OF SHORT WAVES PHASE INTO A
DEEP AND LARGE 500HPA CUT OFF OVER THE MISSISSIPPI VALLEY AS
ANOTHER CUTOFF ORGANIZES OVER SOUTH CENTRAL CANADA. THESE SYSTEMS
INTERACT WITH EACH OTHER DURING THE EXTENDED PERIOD CREATING A
DUMBELLING ACTION AROUND EACH OTHER OVER THE GRTLKS..MIDWEST AND
UPR GRT PLAINS FOR MUCH OF THE WEEK TILL THEY PHASE INTO A MASSIVE
CUTOFF LOVER THE EASTERN SEABOARD TO END THE WEEK. THE MAIN STORM
TRACKS WILL PASS TO OUR WEST AT FIRST...WITH THE FINAL ONE A
COASTAL BY THE WEEKEND. THE RESULT WILL BE AN UNSETTLED PERIOD AS
WE HEAD INTO THE THANKSGIVING TRAVEL AND HOLIDAY PERIOD. THERE
WILL BE SEVERAL FRONTAL PASSAGES AND THEIR BOUTS OF PRECIPITATION.
TEMPS WILL REMAIN NR OR ABOVE NORMAL TILL THE END OF THE WEEK WHEN
IT WILL TURN NOTICEABLY COLDER.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE REGION SATURDAY THROUGH
SUNDAY.
TODAY...MVFR LEVEL CLOUDS HAVE DEVELOPED AT KGFL AND KALB EARLY THIS
MORNING...AND WILL LIKELY CONTINUE THROUGH AT LEAST 15Z...BEFORE
RISING TO VFR LEVELS. HOWEVER...THERE IS SOME POSSIBILITY OF MVFR
CIGS PERSISTING EVEN LONGER. AT KPOU...EXPECT VFR CONDITIONS THROUGH
AT LEAST EARLY TONIGHT.
TONIGHT...CONFIDENCE DECREASING ON WHETHER ADDITIONAL LOW CLOUDS
REDEVELOP LATER TONIGHT...OR SKIES REMAIN CLEAR WITH PATCHY GROUND
FOG DEVELOPMENT. LATEST MODEL GUIDANCE HINTS AT POSSIBLE MVFR/IFR
CIGS DEVELOPING AT KGFL AND KALB AFTER 06Z/SUN. AT THIS TIME...DUE
TO LINGERING UNCERTAINTY...WE HAVE INDICATED FEW-SCT CLOUDS BELOW
1000 FT AGL AT KGFL AND KALB AFTER 08Z/SUN...BUT SHOULD MOISTENING
TRENDS CONTINUE IN MODEL GUIDANCE...WE MAY NEED TO CONSIDER SOME IFR
CIGS LATER TONIGHT AT THESE TERMINALS. AT KPOU...CONDITIONS SHOULD
REMAIN VFR...WITH PERHAPS SOME MVFR VSBYS DEVELOPING LATE DUE TO
PATCHY GROUND FOG.
WINDS WILL REMAIN FROM THE W TO NW AT 5-10 KT TODAY...BECOMING
LIGHT/VARIABLE TONIGHT. SOME GUSTINESS IS POSSIBLE THROUGH SAT
MORNING...ESP AT KALB...POSSIBLY REACHING 15-20 KT. IN ADDITION...AT
KGFL...SOME VARIATIONS IN WIND DIRECTION IS POSSIBLE THIS AFTERNOON
DUE TO LOCALIZED TOPOGRAPHICAL EFFECTS.
OUTLOOK...
SUN...VFR...NO SIG WX.
MON-TUE...VFR-MVFR...CHC OF RAIN.
WED...VFR...CHC OF SHOWERS.
&&
.HYDROLOGY...
WITH DRY CONDITIONS EXPECTED TO LAST AT LEAST INTO MONDAY RIVERS
WILL CONTINUE RECEDE THROUGH MONDAY. THE NEXT THREAT OF RAIN WILL
BE LATE MONDAY INTO TUESDAY. CONSENSUS OF MODELS IS FOR 0.10 TO
0.70 INCHES MAINLY IN THE SOUTHEAST. BUT ALOT OF UNCERTAINTY
REMAINS WITH THE STORM TRACK AND AMOUNTS COULD VARY. THIS EVENT
SHOULD HAVE MODEST IMPACT ON RIVERS AND STREAMS. FURTHER OUT AN
UNSETTLED PERIOD OF WEATHER THURSDAY INTO THE WEEKEND COULD RESULT
IN SIGNIFICANT PRECIPITATION AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SNYDER
NEAR TERM...NAS
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...NAS
HYDROLOGY...SNYDER
000
FXUS61 KBOX 211856
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
156 PM EST SAT NOV 21 2009
.SYNOPSIS...
HIGH PRESSURE WILL MOVE FROM THE GREAT LAKES INTO SOUTHEAST CANADA
TONIGHT...THEN MOVE EAST OF NOVA SCOTIA MONDAY. A WEAK LOW PRESSURE
WILL APPROACH SOUTHERN NEW ENGLAND FROM THE SOUTH MONDAY NIGHT AND
TUESDAY. WEAK HIGH PRESSURE WILL PROBABLY RESULT IN A DRY
THANKSGIVING...BEFORE A POSSIBLE COASTAL STORM ON FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH CLOUDS CONTINUE TO STREAM ACROSS SOUTHERN NEW ENGLAND...WITH
THE THICKEST CLOUDS NOW ACROSS CAPE COD AND THE ISLANDS. FARTHER
WEST...PLENTY OF CLOUDS FROM THE GREAT LAKES BANKED UP AGAINST THE
WEST SLOPES OF THE BERKSHIRES. WITH WINDS SHIFTING TO THE NORTH AND
REMAINING FAIRLY LIGHT...DO NOT EXPECT THESE CLOUDS TO SPILL OVER THE
BERKSHIRES INTO SOUTHERN NEW ENGLAND.
USED A BLEND OF MOS GUIDANCE FOR TEMPERATURES TONIGHT.
&&
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
HIGH PRESSURE REMAINS ACROSS NORTHERN NEW ENGLAND AND SOUTHEAST
CANADA. THIS SHOULD MEAN ANOTHER MOSTLY SUNNY DAY...BUT THIS TIME
WITH ONSHORE WINDS BY AFTERNOON. THESE ONSHORE WINDS COULD LEAD
MARINE STRATUS LATE IN THE DAY INTO SUNDAY NIGHT...PARTICULARLY SOUTH
AND EAST OF I-95 IN MA AND RI. GIVEN THE EXPECTED TIMING OF THE WIND
SHIFT THOUGH...THINKING THIS MAY BE MORE OF A CONCERN SUNDAY NIGHT.
MOS TEMPERATURES LOOK REASONABLE ONCE AGAIN...SO USED A BLEND OF THE
MAV/MET GUIDANCE.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
CONFIDENCE IS BELOW AVERAGE DURING THIS PERIOD DUE TO SPREAD IN
MODEL SOLUTIONS AS WELL AS SOME RUN TO RUN DISCONTINUITY.
SEEING TENDENCY FOR VARIOUS MEDIUM RANGE MODELS TO PROJECT
MEASURABLE RAIN FOR MON NIGHT THRU TUE...AND THIS IS SUPPORTED BY
SREF PROBABILITIES. NOTICED THAT 00Z ECMWF IS WETTER THAN ITS PRIOR
RUN. THERE ARE TIMING AND QPF VARIATIONS AMONG THE MODELS.
THUS...HAVE NOT TRIED TO BE TOO PRECISE ON TIMING OF ONSET AND
ENDING OF POPS AND HAVE CAPPED AT HIGH CHANCE FOR NOW. SUSPECT MOST
LOCATIONS WILL GET MEASURABLE SOMETIME IN THE MON NIGHT TO TUE NIGHT
TIME FRAME BUT CANNOT PIN THE TIMING DOWN ANY BETTER. THE GLOBAL GEM
STILL LOOKS TOO ROBUST GIVEN THAT THIS SYSTEM IS ASSOCIATED WITH A
DAMPENING SHORT WAVE TROF MOVING INTO THE LONG WAVE RIDGE POSITION.
HOWEVER...AS WEAK AS SYSTEM IS...DOES LOOK LIKE DECENT OVERRUNNING
WITH A SUBTROPICAL MOISTURE SOURCE. AS FAR AS TIMING...AM SUSPICIOUS
THAT DRY LOW LEVEL AIR ASSOCIATED WITH MODERATELY STRONG HIGH PRES
CENTERED OVER NOVA SCOTIA AT THE OUTSET MAY DELAY THE SPREAD OF RAIN
INTO SOUTHWEST NH AND NORTHEAST MA MON NIGHT.
WED IS A LITTLE COMPLICATED WITH VIGOROUS NEGATIVE TILT SHORT WAVE
TROF ROTATING THROUGH THE GREAT LAKES. SOUTHERN NEW ENGLAND IS
FAIRLY WELL EAST OF SIGNIFICANT DYNAMICS. GFS DEPICTS SE FLOW THAT
COULD IN ITSELF CONTRIBUTE TO LOW CLOUDS AND DRIZZLE WHEREAS THE
ECMWF SHOWS LESS RH AND FLAT GRADIENT AMIDST WEAK SURFACE RIDGE.
HAVE GONE WITH SLIGHT CHANCE TO CHANCE POPS. TEMPERATURES MAY BE
TRICKY FOR WED GIVEN WARM AIR MASS ALOFT WITH 8+C 850 MB
TEMPERATURES BUT INVERSION MAY PREVENT REALIZING THE RELATIVE WARMTH
AT THE SURFACE. IF GET ENOUGH SUN...THEN WED MAX TEMPERATURES MAY
END UP CONSIDERABLY HIGHER THAN CURRENTLY FORECAST.
THANKSGIVING DAY CURRENTLY LOOKS DRY WITH PERHAPS A SUNNY START
BEFORE INCREASING CLOUDS DURING THE AFTERNOON AHEAD OF THE NEXT
SYSTEM. A VIGOROUS SHORT WAVE TROF HELPS INITIATE A COASTAL LOW BUT
AGAIN MEDIUM MODELS NOT IN GOOD AGREEMENT IN HANDLING THIS SYSTEM
WITH REGARD TO INTENSITY AND TRACK. HAVE GONE WITH CHC POPS THU
NIGHT AND FRI. AIR MASS MAY COOL SUFFICIENTLY TOWARD BACK PART OF
STORM TO CAUSE PTYPE UNCERTAINTY. POTENTIAL FOR RAIN TO MIX WITH OR
CHANGE TO SNOW OVER THE HIGHER ELEVATIONS OF OUR NW ZONES ON FRI BUT
CONFIDENCE OF THIS ACTUALLY OCCURRING IS CURRENTLY LOW.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
TONIGHT...VFR. PATCHY FOG WITH BRIEF MVFR CIGS/VSBYS LATE AT NIGHT
IN THE NORMALLY SUSCEPTIBLE VALLEYS.
SUNDAY...VFR. MAY SEE PATCHY VFR TO LOCAL MVFR CIGS ALONG THE COAST
DURING THE LATE MORNING AND AFTERNOON.
SUNDAY NIGHT...VFR MOST LOCATIONS. GREATER RISK OF MVFR CIGS ALONG
THE EAST COAST AND SOUTH AND EAST OF A LINE FROM KBOS-KPVD.
CONFIDENCE ON THIS IS NOT HIGH AT THIS TIME.
OUTLOOK /MONDAY THROUGH WEDNESDAY/...
MON THRU WED...VFR MON BECOMING MVFR WITH AREAS IFR IN RAIN AND FOG
MON NIGHT THROUGH TUE NIGHT. MVFR CIGS MAY PERSIST INTO WED.
&&
.MARINE...
HIGH PRES BUILDING N OF THE WATERS TONIGHT. WINDS GRADUALLY SHIFTING
N TONIGHT...THEN NE SUNDAY INTO SUNDAY NIGHT. SEAS BELOW 5 FT TONIGHT
INTO EARLY SUNDAY. DO EXPECT SEAS TO BUILD OVER 5 FT ACROSS THE OUTER
COASTAL WATERS SUNDAY AFTERNOON INTO SUNDAY NIGHT ONCE NE WINDS GET
ESTABLISHED. THERE IS STILL A QUESTION ABOUT STRENGTH OF THESE
WINDS...WHICH WILL BE ENTIRELY DEPENDENT UPON THE APPROACH OF A LOW
PRESSURE FROM THE MID ATLANTIC COAST.
OUTLOOK /MONDAY THROUGH WEDNESDAY/...
PERSISTENT E GRADIENT WITH CONSIDERABLE FETCH WILL LIKELY KEEP SEAS
NEAR OR ABOVE 5 FT EXPOSED COASTAL WATERS MON NIGHT THRU WED MORNING AND
MAY BE STRONG ENOUGH TO MEET SCA WIND THRESHOLDS OVER MOST OF WATERS.
RESPITE LIKELY LATE WED THRU THU BEFORE RISK OF POTENT COASTAL LOW PRES
SYSTEM TOWARD END OF WEEK.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...BELK/THOMPSON
NEAR TERM...BELK
SHORT TERM...BELK
LONG TERM...THOMPSON
AVIATION...BELK/THOMPSON
MARINE...BELK/THOMPSON
000
FXUS61 KALY 211829
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
129 PM EST SAT NOV 21 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL COVER THE NORTHEAST...SLIDING
OFF INTO CANADIAN MARITIMES LATE MONDAY. CLOUDS OVER THE REGION
WILL DIMINISH WITH GENERALLY CLEAR SKIES SUNDAY INTO MONDAY. OUR
WEATHER WILL TURN UNSETTLED MUCH OF THE UPCOMING WEEK. FIRST A LOW
PRESSURE AREA WILL MOVE NORTHEAST FROM THE CAROLINA COAST MONDAY
NIGHT AND TUESDAY. THEN MIDWEEK A SERIES OF MUCH STRONGER STORMS
WILL MOVE THOUGH THE MIDWEST AND GREAT LAKES.
&&
.NEAR TERM /THROUGH TONIGHT/...
SURFACE HIGH IN THE GREAT LAKES AND OH VALLEY CONTINUES TO
GRADUALLY BUILD INTO THE REGION. WEST TO NORTHWEST FLOW ACROSS THE
LAKES AND AN INVERSION AT THE BOUNDARY LAYER HAS RESULTED IN
WIDESPREAD CLOUD COVER. HOWEVER...AREAS IN LEE OF THE EASTERN
CATSKILLS...BERKSHIRES AND SOUTHERN GREEN MOUNTAINS HAVE SEEN
RELATIVELY LITTLE CLOUD COVER DUE TO DOWNSLOPE.
RECENT SATELLITE TRENDS ARE CONSISTENT WITH TRENDS SEEN IN
GUIDANCE...WITH CLEARING AND DRYING BEGINNING TO WORK SOUTH FROM
NEAR THE CANADIAN BORDER. THIS CLEARING AND DRYING WILL BUILD SOUTH
THROUGH THE EVENING AND NIGHT...BUT THERE IS SOME QUESTION ABOUT
HOW FAR WEST THE CLEARING WILL GET...DUE TO PROXIMITY TO LAKE
ONTARIO. FOR AREAS AROUND AND EAST OF THE HUDSON VALLEY...CLEARING
SHOULD SPREAD ACROSS THE REGION BY THE EARLY MORNING HOURS. AREAS
OF THE WESTERN MOHAWK VALLEY TO SCHOHARIE VALLEY AND PARTS OF THE
CATSKILLS MAY BE A BIT SLOWER TO CLEAR. STILL...BY SUNRISE...
SUGGESTING ALL AREAS WILL CLEAR. WITH AT LEAST A COUPLE/FEW HOURS
OF CLEARING BEFORE SUNRISE...TEMPERATURES SHOULD FALL TO NEAR
GUIDANCE LEVELS...EVEN THOUGH TEMPERATURES WILL NOT FALL MUCH UNTIL
CLEARING OCCURS.
UPSTREAM SURFACE DEW POINTS NOT TOO DRY...SO LOW TEMPERATURES SHOULD
NOT BE MUCH BELOW GUIDANCE IN AREAS THAT SEE THE LONGEST PERIOD OF
CLEARING...AND MAYBE A BIT ABOVE GUIDANCE WHERE CLEARING IS MOST
DELAYED. MOST TEMPERATURE BUST POTENTIAL TONIGHT LOOKS TO BE IN THE
WESTERN MOHAWK VALLEY...SCHOHARIE VALLEY AND PARTS OF THE
CATSKILLS...WHERE TIMING OF CLEARING IN QUESTION.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
RATHER IMPRESSIVE RIDGE OVER RGN FOR THIS PERIOD AT SFC AND ALOFT.
THE 500HPA SHORT WAVE AXIS (FM W MD TO CAPE COD) WILL BE EXITING
THE RGN AT START OF THE PERIOD AND TAKING WITH IT MOST OF THE
FORCING THAT RESULTED IN THE CLOUDS THAT WERE TRAPPED UNDER THE
INVERSION. WRF ALSO SHOWS DRYING AND DRY AIR ADVECTION JUST PRIOR
TO THIS PERIOD. SO SUNDAY SHOULD BE A SUNNY DAY WITH ABV NORMAL
TEMPS AND ANY RESIDUAL CLOUDS WILL GO QUICKLY.
FOR THE MOST PART WE HAVE MODEL CONSISTENCY (ECMWF/GEM/GFS/NAM)
FOR SYSTEM PLACEMENT AND TIMING THROUGH MONDAY. THE EXCEPTION IS
THE NAM NOW PUSHES THREAT OF RAIN INTO SE FCA LATE MONDAY...ABOUT
3-6 HOURS FASTER THAN REST OF THE CROWD. BUT THE CONSENSUS
REMAINS FOR A PARTLY SUNNY AND DRY DAY IN MOST OF THE AREA WITH
JUST CHC POPS ALONG THE SOUTHERN PERIPHERAL COUNTIES. SO THERE
SHOULD BE LITTLE CHANGE IN THE FORECAST.
THE OTHER DISCONTINUITY IS THE MAV AND MET TEMPS ARE ABOUT 5-10
DEGREES APART SUNDAY...THE MET BEING THE COLD ONE. THIS IN SPITE
OF BOTH MODELS INDICATING SIMILAR SENSIBLE WEATHER (SUNNY..LIGHT
WINDS..UNDER HIGH), AND HAVING ABOUT THE SAME 925 HPA FORECASTED
TEMPS (3-5C)AS WELL. THIS DIFFERENCE IN THE MET/MAV IS REFLECTED
IN THEIR MODEL SOUNDINGS AND PARTICULARLY AROUND MAX TEMP TIME @
18UTC. WHILE THE NEW NAM PHYSICS HAVE GENERALLY BEEN BETTER SINCE
THE UPGRADE SOMETHING SEEMS SQUIRRELLY IN THE MET TEMPS SUNDAY.
TODAY SO FAR WHERES THERE NO SUN TEMPS ARE STILL MID 40S TO AROUND
50...AND WELL INTO THE 50S WHERE THE SUN IS SHINING. COULD JUST
BLEND THE TWO...BUT GIVEN THE COMPARISON TO TODAY..FCST WILL GO
WITH THE MAV TEMPS
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MON NT-TUE...STILL QUITE A BIT OF UNCERTAINTY REGARDING NEXT
SYSTEM...CURRENTLY DEVELOPING ALONG THE WESTERN GULF COAST. THE
GENERAL TREND IN THE MODELS OVER THE LAST 24 HOURS HAS BEEN
WEAKER...AND FURTHER S/E WITH THE TRACK. THE 00Z/21 GEM IS MOST
AGGRESSIVE WITH THIS FEATURE...TRACKING IT OFF THE NEW ENGLAND
COAST...BUT STILL FAR ENOUGH WEST TO BRING AT LEAST SOME LIGHT RAIN
TO THE S/E HALF OF REGION. THE 00Z/21 GFS IS A BIT FURTHER
S/E...WHILE THE 00Z/21 ECMWF AND AT LEAST HALF OF THE MREFS KEEP
MOST PRECIP OUT OF OUR REGION...JUST CLIPPING FAR SE AREAS LATE MON
NT INTO EARLY TUE. BASED ON THIS LINGERING UNCERTAINTY...HAVE
INDICATED ONLY SLIGHT CHC TO LOW CHC POPS FOR RAIN ACROSS SOUTHERN
HALF OF REGION...WHILE KEEPING NORTHERN AREAS DRY. AS FOR
TEMPS...GENERALLY FOLLOWED CLOSE TO GMOS...WITH MINS MAINLY IN THE
30S...AND TUE MAXES MAINLY IN THE UPPER 40S TO LOWER 50S. SHOULD THE
CLOUDS/PRECIP EXTEND FURTHER N/W...EVEN COOLER MAXES ARE POSSIBLE.
TUE NT-WED...WILL INDICATE DRY CONDITIONS DURING THIS PERIOD...AS
MOST MODELS HINT AT SHORTWAVE RIDGING BUILDING INTO THE REGION.
HOWEVER...BY LATE WED...ENERGY AND WARM ADVECTION APPROACHING FROM
THE W MAY LEAD TO SOME RAIN BY LATE WED. THUS...HAVE INDICATED SOME
SLIGHT CHC TO LOW CHC POPS ACROSS SW AREAS FOR LATE WED.
OTHERWISE...EXPECT MAX TEMPS TO RANGE FROM THE MID 40S ACROSS FAR
NORTHERN AREAS...TO THE LOWER/MID 50S ACROSS CENTRAL AND SOUTHERN
AREAS...WITH OVERNIGHT MINS TUE NT MAINLY IN THE MID/UPPER 30S.
WED NT-FRI...MODELS HINT AT ADDITIONAL PRECIP DURING THIS
PERIOD...ALTHOUGH DIFFER ON THE EXACT TRIGGERING MECHANISMS. THE
00Z/GFS HINTS AT A FASTER WAVE MOVING THROUGH LATE WED INTO WED NT
WITH RAIN...WHILE MOST MREF MEMBERS...AND THE ECMWF DEPICT A
SLIGHTLY SLOWER UPPER LEVEL SYSTEM DEVELOPING ACROSS THE GREAT
LAKES...WHILE ANOTHER SFC LOW DEVELOPS ALONG THE SE COAST AND TRACKS
NNE. AT THE VERY LEAST...WILL INDICATE CHC POPS DURING THIS PERIOD
FOR RAIN...ALTHOUGH SOME WET SNOW COULD BE MIXED IN ACROSS HIGHER
ELEVATIONS EARLY THU. THEN...AS MID/UPPER LEVEL CONTINUE TO
COOL...WE EXPECT ANY RAIN TO GRADUALLY MIX WITH/CHANGE TO SNOW
ACROSS HIGHER ELEVATIONS BY LATE THU...AND PERHAPS WITHIN VALLEYS BY
THU NT OR EARLY FRI. WHETHER THIS PRECIPITATION IS WIDESPREAD AND
STEADY...OR MORE SCATTERED AND SHOWERY IS STILL UNCERTAIN...BUT
THERE IS AT LEAST SOME POSSIBILITY FOR PORTIONS OF THE REGION TO
RECEIVE MEASURABLE SNOW SOMETIME DURING THIS PERIOD. FOR
TEMPS...EXPECT MINS WED NT TO MAINLY BE IN THE 30S...WITH THU MAXES
MAINLY IN THE 30S FOR HIGHER ELEVATIONS...AND 40S FOR VALLEYS. FOR
THU NT...EXPECT MINS TO FALL INTO THE 20S FOR HIGHER
ELEVATIONS...AND LOWER/MID 30S FOR THE VALLEYS...WITH FRI MAXES
RANGING FROM THE LOWER/MID 30S ACROSS HIGHER ELEVATIONS...TO THE
UPPER 30S/LOWER 40S WITHIN THE VALLEYS. IT MAY ALSO BECOME QUITE
WINDY BY FRI...DEPENDING ON THE EVOLUTION AND TRACK OF ANY SFC LOW
PASSING TO OUR E OR NE.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE REGION SATURDAY THROUGH
SUNDAY.
TODAY...MVFR LEVEL CLOUDS HAVE DEVELOPED AT KGFL AND KALB EARLY THIS
MORNING...AND WILL LIKELY CONTINUE THROUGH AT LEAST 15Z...BEFORE
RISING TO VFR LEVELS. HOWEVER...THERE IS SOME POSSIBILITY OF MVFR
CIGS PERSISTING EVEN LONGER. AT KPOU...EXPECT VFR CONDITIONS THROUGH
AT LEAST EARLY TONIGHT.
TONIGHT...CONFIDENCE DECREASING ON WHETHER ADDITIONAL LOW CLOUDS
REDEVELOP LATER TONIGHT...OR SKIES REMAIN CLEAR WITH PATCHY GROUND
FOG DEVELOPMENT. LATEST MODEL GUIDANCE HINTS AT POSSIBLE MVFR/IFR
CIGS DEVELOPING AT KGFL AND KALB AFTER 06Z/SUN. AT THIS TIME...DUE
TO LINGERING UNCERTAINTY...WE HAVE INDICATED FEW-SCT CLOUDS BELOW
1000 FT AGL AT KGFL AND KALB AFTER 08Z/SUN...BUT SHOULD MOISTENING
TRENDS CONTINUE IN MODEL GUIDANCE...WE MAY NEED TO CONSIDER SOME IFR
CIGS LATER TONIGHT AT THESE TERMINALS. AT KPOU...CONDITIONS SHOULD
REMAIN VFR...WITH PERHAPS SOME MVFR VSBYS DEVELOPING LATE DUE TO
PATCHY GROUND FOG.
WINDS WILL REMAIN FROM THE W TO NW AT 5-10 KT TODAY...BECOMING
LIGHT/VARIABLE TONIGHT. SOME GUSTINESS IS POSSIBLE THROUGH SAT
MORNING...ESP AT KALB...POSSIBLY REACHING 15-20 KT. IN ADDITION...AT
KGFL...SOME VARIATIONS IN WIND DIRECTION IS POSSIBLE THIS AFTERNOON
DUE TO LOCALIZED TOPOGRAPHICAL EFFECTS.
OUTLOOK...
SUN...VFR...NO SIG WX.
MON-TUE...VFR-MVFR...CHC OF RAIN.
WED...VFR...CHC OF SHOWERS.
&&
.HYDROLOGY...
WITH DRY CONDITIONS EXPECTED TO LAST AT LEAST INTO MONDAY RIVERS
WILL CONTINUE RECEDE THROUGH MONDAY. THE NEXT THREAT OF RAIN WILL
BE LATE MONDAY INTO TUESDAY. CONSENSUS OF MODELS IS FOR 0.10 TO
0.70 INCHES MAINLY IN THE SOUTHEAST. BUT ALOT OF UNCERTAINTY
REMAINS WITH THE STORM TRACK AND AMOUNTS COULD VARY. THIS EVENT
SHOULD HAVE MODEST IMPACT ON RIVERS AND STREAMS. FURTHER OUT AN
UNSETTLED PERIOD OF WEATHER THURSDAY INTO THE WEEKEND COULD RESULT
IN SIGNIFICANT PRECIPITATION AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SNYDER
NEAR TERM...NAS
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...NAS
HYDROLOGY...SNYDER
000
FXUS61 KOKX 211811
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
111 PM EST SAT NOV 21 2009
.SYNOPSIS...
HIGH PRESSURE SLOWLY BUILDS INTO THE NORTHEASTERN UNITED STATES
THROUGH SUNDAY...THEN SLOWLY RETREATS INTO THE CANADIAN MARITIME
PROVINCES THROUGH EARLY NEXT WEEK. MEANWHILE...AN AREA OF LOW
PRESSURE WILL MOVE UP THE SOUTHEAST COAST MONDAY...THEN CONTINUE
NORTHEAST TO A POSITION EAST OF CAPE COD BY WEDNESDAY MORNING.
WEAK HIGH PRESSURE BUILDS IN FROM THE NORTH WEDNESDAY. ANOTHER
STORM SYSTEM WILL THEN IMPACT THE TRI-STATE TO CLOSE THE UPCOMING
WORK WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH CLOUDS THINNING EARLY THIS AFTERNOON. LOW ST/SC OVER CENTRAL
NY/PA IS DRYING UP NICELY. THIS IS RESULTING IN MOSTLY CLOUDY
SKIES. THE FORECAST REMAINS GENERALLY UNCHANGED EXCEPT FOR A MINOR
TWEAK TO CLOUD COVER (GENERALLY DOWNWARD). TEMPS APPROACHING
AFTERNOON HIGHS AT THIS TIME...WITH NO FURTHER UPDATES PLANNED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
RIDGING BUILDING IN FROM 700 HPA TO THE SURFACE SHOULD CREATE
ENOUGH SUBSIDENCE FOR MAINLY CLEAR SKY CONDITIONS TONIGHT...AND
ALLOW FOR DECOUPLING OF THE BOUNDARY LAYER TO PRODUCE LIGHT WINDS
AT THE SURFACE. AS A RESULT SHOULD HAVE DECENT RADIATIONAL
COOLING TONIGHT...WITH LOWS IN THE 30S (AROUND 40-MID 40S NYC
METRO). THESE VALUES ARE NEAR NORMAL...EXCEPT 3-5 DEGREES ABOVE
NORMAL IN THE NYC METRO AND FOLLOWED COOLER MET GUIDANCE (MAV TOO
WARM GIVEN EXPECTED RADIATIONAL COOLING AND RELATIVELY SHALLOW
NATURE OF COLD AIR MOVING IN).
DEEP LAYER RIDGING BUILDS IN SUNDAY...LIMITING MIXING TO AROUND
950 HPA AND MINIMIZING ANY CLOUD COVER. SO EVEN WITH ABUNDANT
SUNSHINE...WILL ONLY HAVE HIGHS AROUND 50 - OR NEAR NORMAL FOR
THIS TIME OF YEAR).
RIDGE AXIS SLIDES OFFSHORE SUNDAY NIGHT...ALLOWING FOR ONSHORE
FLOW TO SET UP...BUT DAMMING SURFACE HIGH WILL CONTINUE LOW LEVEL
COLD ADVECTION...AS A RESULT WILL END UP SEEING LOWS A COUPLE OF
DEGREES COOLER THAN TONIGHT (ONCE AGAIN USED COOLER MET
GUIDANCE).
GFS AND ECMWF HAVE A FLATTER BASE TO THE SURFACE RIDGE THAN DO
THE NAM/CMC GGEM MONDAY-MONDAY NIGHT. THIS DIFFERENCE ALLOWS FOR
LOW LEVEL MOISTURE TO GET FURTHER INLAND IN THE GFS/ECMWF THAN IN
THE NAM/GGEM. THE SREF SUPPORTS THE STRUCTURE OF THE GFS/ECMWF SO
HAVE OPTED FOR A GFS/ECMWF BLEND FOR THE REMAINDER OF THE SHORT
TERM.
WITH OVER RUNNING SETTING UP ACROSS THE ENTIRE TRI-STATE MONDAY
AFTERNOON BRING CHANCE POPS TO ALL AREAS BY LATE AFTERNOON AND
CONTINUE MONDAY NIGHT. BETTER CHANCE OF RAIN MONDAY NIGHT WITH
500 AND 700 HPA SHORTWAVES CROSSING THE AREA AS WELL. FOR
TEMPERATURES USED MET/MAV BLEND MONDAY AND MEX/MEX ENSEMBLE MEAN
BLEND MONDAY NIGHT...WITH HIGHS NEAR NORMAL ON MONDAY AND 4-8
DEGREES ABOVE NORMAL MONDAY NIGHT (CLOUD COVER/RAIN LIMITING
DIURNAL RANGE).
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
LOW CONFIDENCE FORECAST IN THE EXTENDED WITH ALL THE MODELS
SHOWING SOMETHING DIFFERENT. GGEM IS MOST PROGRESSIVE WITH
COASTAL LOW FOR TUESDAY...GEFS SLOWEST AND MOST SUPPRESSED TO THE
SOUTH (LIKE YESTERDAY/S 12Z ECMWF) AND GFS AND ECMWF IN BETWEEN
(WITH ECMWF MORE PROGRESSIVE THAN THE GFS).
FOR THE NEXT SYSTEM MOVING THROUGH THE GREAT LAKES INTO THE
NORTHEAST DURING THE MIDDLE TO LATE PART OF NEXT WEEK. THE GFS
MAINTAINS TWO DISTINCT CUTOFF LOWS (ACTUALLY LINKING THE FIRST
ONE WHICH IT HAS PASSING TO OUR NW WEDNESDAY WITH THE DEPARTING
STORM SYSTEM EARLY THIS WEEK)...WHILE THE ECMWF ABSORBS THE
SECOND CHUNK OF UPPER LEVEL ENERGY INTO THE FIRST CUTOFF LOW WITH
THIS LOW SLOWLY CROSSING THE NE LATE NEXT WEEK. THE GGEM
MAINTAINS TWO DISTINCT CIRCULATIONS WITHOUT ANY PHASING...BUT
DOES SUGGEST BY LOOKING AT THE INDIVIDUAL SYSTEMS THAT THE ECMWF
SOLUTION IS PLAUSIBLE. FOR NOW HAVE OPTED FOR A GFS/ECMWF BLEND
IN THE EXTENDED...BUT AS NOTED IN THE FIRST SENTENCE OF THE FIRST
PARAGRAPH...THIS IS A LOW CONFIDENCE FORECAST...SO EXPECT
CHANGES.
APPEARS FOR NOW THAT RAIN WILL LINGER INTO TUESDAY...THEN TAPER
OFF TUESDAY EVENING AS COASTAL LOW DEPARTS (CHANCE POPS TUESDAY
AND SLIGHT CHANCE POPS TUESDAY NIGHT). WHILE THERE IS SOME
SUGGESTION WEDNESDAY WILL END UP DRY WITH HIGH PRESSURE BUILDING
IN...IF GFS ENDS UP BEING RIGHT....COULD SEE SOME LIGHT SHOWERS
WEDNESDAY...SO SLIGHT CHANCE POPS. ON THE FLIP SIDE...GFS WOULD
HAVE THINGS DRY WEDNESDAY NIGHT/THURSDAY...BUT ECMWF BRINGS IN
PRECIPITATION AHEAD OF CONSOLIDATED CUTOFF...SO HAVE SLIGHT
CHANCE POPS BOTH PERIODS. BOTH MODELS SUGGEST RAIN FROM CUTOFF
LOW THURSDAY NIGHT/FRIDAY (POSSIBLY MIXED WITH/CHANGING TO SNOW
N/W OF NYC DEPENDING ON EXACT TRACK OF CUTOFF LOW AND HOW MUCH
LOW LEVEL COLD AIR ACTUALLY ENDS UP MOVING IN WITH IT)...SO
CHANCE POPS.
FOR TEMPERATURES USED A MEX/MEX ENSEMBLE MEAN BLEND WITH THE HIGH
MEMBER OF THE MEX ENSEMBLE MEAN BLENDED IN WEDNESDAY NIGHT-
THURSDAY NIGHT TO REFLECT WARMER ECMWF SOLUTION AT THOSE TIMES.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
NW FLOW UNDER 10 KT SHOULD VEER N TONIGHT...AND THEN NE WITH SPEEDS
INCREASING TO AROUND 10 KT...HIGHER AT NYC/COASTAL TERMINALS...
TOWARD OR JUST AFTER DAYBREAK SUNDAY MORNING AS HIGH PRESSURE OVER
THE THE OH VALLEY BUILDS NE INTO NEW ENGLAND. RADIATION FOG WITH
MVFR CONDITIONS MAY IS LIKELY LATE TONIGHT AT KSWF AND KGON...AND
WILL HAVE TO MONITOR OTHER TERMINALS OUTSIDE THE NYC URBAN HEAT
ISLAND FOR THIS POSSIBILITY CLOSE TO/JUST AFTER SUNRISE.
OUTLOOK 18Z SUNDAY THROUGH THU...
SUNDAY AFTERNOON/NIGHT...VFR.
MON...SUB-VFR POSSIBLE.
MON NIGHT-TUE...SUB-VFR LIKELY.
TUE NIGHT-WED...BECOMING VFR.
THU...SUB-VFR POSSIBLE.
&&
.MARINE...
HIGH PRESSURE BUILDING INTO THE AREA WATERS TODAY RESULTS IN WEST
TO NORTHWEST WINDS. WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS. THE HIGH BUILDS INTO SOUTHEASTERN CANADA AND
NORTHERN NEW ENGLAND TONIGHT AND SUNDAY AND STRENGTHENS. WINDS
SHIFT TO THE NORTH THE TO THE NORTHEAST. SUNDAY NIGHT AND MONDAY
THE HIGH CONTINUES TO STRENGTHEN...THERE IS ALSO THE POTENTIAL
FOR A COASTAL LOW TO MOVE INTO THE HIGH. THIS WILL INCREASE THE
WINDS...GUSTS...AND SEAS ACROSS THE AREA WITH SMALL CRAFT
CONDITIONS BECOMING LIKELY BY SUNDAY NIGHT. WINDS COULD DROP
BELOW SMALL CRAFT LEVELS TUESDAY AS THE FORECAST WATERS ARE
BETWEEN TWO LOW PRESSURE SYSTEMS. ANOTHER LOW MAY APPROACH FROM
THE WEST DURING TUESDAY AND INTO WEDNESDAY. THERE IS SOME
UNCERTAINTY TO THE TRACK AND TIMING OF THE LOW AT THIS TIME. SEAS
ON THE OCEAN WILL LIKELY REMAIN AT SMALL CRAFT LEVELS INTO
WEDNESDAY.
&&
.HYDROLOGY...
DRY THROUGH MONDAY MORNING. A QUARTER TO A HALF AN INCH OF
RAINFALL IS POSSIBLE MONDAY EVENING THROUGH TUESDAY WITH
LOCALLY HIGHER AMOUNTS WITHIN THE REASONABLE REALM OF
POSSIBILITIES. MORE PRECIPITATION IS EXPECTED TOWARDS THE END OF
NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...BS
NEAR TERM...BS
SHORT TERM...PFM
LONG TERM...PFM
AVIATION...MET
MARINE...BG/PFM
HYDROLOGY...BG/PFM
000
FXUS61 KALY 211736
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
1236 PM EST SAT NOV 21 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL BUILD INTO NEW YORK
AND NEW ENGLAND THROUGH SUNDAY AND THEN LIFT NORTHEAST INTO THE
CANADIAN MARITIMES ON MONDAY. A LOW PRESSURE SYSTEM WILL THEN START
TO LIFT NORTHEAST FROM THE CAROLINA COAST MONDAY MORNING...AND PASS
SOUTHEAST OF LONG ISLAND TUESDAY MORNING...BRINGING UNSETTLED
WEATHER TO MUCH OF OUR REGION STARTING LATE MONDAY OR MONDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CLOUDS CONTINUE TO SPREAD ACROSS THE REGION AS LAKE EFFECT
MOISTURE GETS TRAPPED BENEATH A BOUNDARY LAYER INVERSION. AREAS
EAST OF THE SOUTHERN GREEN MOUNTAINS AND BERKSHIRES...WHERE SOME
DOWNSLOPE IS OCCURRING...ARE REMAINING PARTLY TO MOSTLY SUNNY.
INCREASING SKY COVER FOR MANY AREAS THIS AFTERNOON...BUT SOME
HINTS IN LATEST GUIDANCE THAT SOME AREAS MAY SEE THE CLOUDS BREAK
UP TO SOME DEGREE. SO...GOING MOSTLY CLOUDY IN MANY AREAS. BASED
ON CURRENT TEMPERATURES AND AREA 12Z SOUNDINGS...CURRENT MAX
TEMPERATURES LOOK IN THE BALL PARK. EVERYTHING ELSE UNTOUCHED.
PREV AFD BELOW...
CLOUDS WILL SLOWLY SHRINK ACROSS FA THIS
MORNING AS STRATO CU ASSOCIATED WITH UPPER LEVEL TROUGH SLIDE
THROUGH FA. LAKE RESPONSE HAS BEEN WEAK AT BEST AND WITH AIRMASS
NOT BEING VERY COLD EXPECT THAT LAKE INDUCED CLOUDS WILL ONLY
LINGER ACROSS PORTIONS OF WESTERN ADIRONDACKS AND MOHAWK VALLEY
INTO EARLY THIS AFTERNOON AND THEN START TO DISSIPATE. WILL KEEP
FORECAST DRY TODAY AND HAVE TEMPS IN MOST AREAS A FEW DEGREES
BELOW YESTERDAY WITH HIGHS GENERALLY IN THE MID 40S TO MID 50S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
RIDGE OF HIGH PRESSURE WILL BE CENTERED OVER FA LATE TONIGHT INTO
EARLY SUNDAY AND THEN START TO LIFT NORTHEAST INTO CANADA. THIS
WILL RESULT IN MAINLY CLEAR SKIES WITH SEASONABLE TEMPS TONIGHT
WITH LOWS IN THE MID 20S TO MID 30S.
ON SUNDAY EXPECT THAT TEMPS MAYBE A FEW DEGREES COOLER IN THE
VALLEYS THAN TODAY AS DESPITE NEARLY FULL SUN...ORIENTATION OF
HIGH WILL RESULT IN A WEAK LOW LEVEL EASTERLY FLOW AND MIXING WILL
BE POOR ONLY UP TO 925 MB. HIGHS ON SUNDAY IN THE UPPER 40S TO
LOWER 50S.
ON SUNDAY NIGHT EXPECT MAINLY CLEAR SKIES IN THE EVENING AND THEN
PARTLY CLOUDY CONDITIONS LATE AS HIGH CLOUDS START TO LIFT
NORTHWARD AHEAD OF NEXT SYSTEM. LOWS SHOULD BE SIMILAR TO SATURDAY
NIGHT IN THE MID 20S TO LOWER 30S.
MONDAY LOOKS TO BE THE TRANSITION DAY WITH UNCERTAINTY STILL ON
EXACT TRACK AND ORIENTATION OF PCPN SHIELD...GEM APPEARS TO BE
THE FASTEST AND WETTEST WITH NAM NOT FAR BEHIND AS BOTH HAVE
LEADING EDGE OF PCPN SHIELD AT LEAST NORTH OF I90 BEFORE 00Z TUE AND
QPF AMOUNTS OF A TENTH TO A QUARTER OF AN INCH ACROSS FA. WHILE GFS
AND ECMWF SIGNIFICANTLY SLOWER WITH ONLY LIGHT RAIN AND A FEW
HUNDREDTHS OF AN INCH OF QPF INTO SE THIRD OF FA BEFORE 00Z TUE.
FOR NOW WILL KEEP FORECAST DRY WITH INCREASING CLOUDS ON MONDAY
MORNING AND THEN HAVE SLIGHT CHANCE TO CHANCE POPS SOUTH OF I90
MONDAY AFTERNOON. HIGH TEMPS ON MONDAY EXPECTED TO BE IN THE MID
TO UPPER 40S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MON NT-TUE...STILL QUITE A BIT OF UNCERTAINTY REGARDING NEXT
SYSTEM...CURRENTLY DEVELOPING ALONG THE WESTERN GULF COAST. THE
GENERAL TREND IN THE MODELS OVER THE LAST 24 HOURS HAS BEEN
WEAKER...AND FURTHER S/E WITH THE TRACK. THE 00Z/21 GEM IS MOST
AGGRESSIVE WITH THIS FEATURE...TRACKING IT OFF THE NEW ENGLAND
COAST...BUT STILL FAR ENOUGH WEST TO BRING AT LEAST SOME LIGHT RAIN
TO THE S/E HALF OF REGION. THE 00Z/21 GFS IS A BIT FURTHER
S/E...WHILE THE 00Z/21 ECMWF AND AT LEAST HALF OF THE MREFS KEEP
MOST PRECIP OUT OF OUR REGION...JUST CLIPPING FAR SE AREAS LATE MON
NT INTO EARLY TUE. BASED ON THIS LINGERING UNCERTAINTY...HAVE
INDICATED ONLY SLIGHT CHC TO LOW CHC POPS FOR RAIN ACROSS SOUTHERN
HALF OF REGION...WHILE KEEPING NORTHERN AREAS DRY. AS FOR
TEMPS...GENERALLY FOLLOWED CLOSE TO GMOS...WITH MINS MAINLY IN THE
30S...AND TUE MAXES MAINLY IN THE UPPER 40S TO LOWER 50S. SHOULD THE
CLOUDS/PRECIP EXTEND FURTHER N/W...EVEN COOLER MAXES ARE POSSIBLE.
TUE NT-WED...WILL INDICATE DRY CONDITIONS DURING THIS PERIOD...AS
MOST MODELS HINT AT SHORTWAVE RIDGING BUILDING INTO THE REGION.
HOWEVER...BY LATE WED...ENERGY AND WARM ADVECTION APPROACHING FROM
THE W MAY LEAD TO SOME RAIN BY LATE WED. THUS...HAVE INDICATED SOME
SLIGHT CHC TO LOW CHC POPS ACROSS SW AREAS FOR LATE WED.
OTHERWISE...EXPECT MAX TEMPS TO RANGE FROM THE MID 40S ACROSS FAR
NORTHERN AREAS...TO THE LOWER/MID 50S ACROSS CENTRAL AND SOUTHERN
AREAS...WITH OVERNIGHT MINS TUE NT MAINLY IN THE MID/UPPER 30S.
WED NT-FRI...MODELS HINT AT ADDITIONAL PRECIP DURING THIS
PERIOD...ALTHOUGH DIFFER ON THE EXACT TRIGGERING MECHANISMS. THE
00Z/GFS HINTS AT A FASTER WAVE MOVING THROUGH LATE WED INTO WED NT
WITH RAIN...WHILE MOST MREF MEMBERS...AND THE ECMWF DEPICT A
SLIGHTLY SLOWER UPPER LEVEL SYSTEM DEVELOPING ACROSS THE GREAT
LAKES...WHILE ANOTHER SFC LOW DEVELOPS ALONG THE SE COAST AND TRACKS
NNE. AT THE VERY LEAST...WILL INDICATE CHC POPS DURING THIS PERIOD
FOR RAIN...ALTHOUGH SOME WET SNOW COULD BE MIXED IN ACROSS HIGHER
ELEVATIONS EARLY THU. THEN...AS MID/UPPER LEVEL CONTINUE TO
COOL...WE EXPECT ANY RAIN TO GRADUALLY MIX WITH/CHANGE TO SNOW
ACROSS HIGHER ELEVATIONS BY LATE THU...AND PERHAPS WITHIN VALLEYS BY
THU NT OR EARLY FRI. WHETHER THIS PRECIPITATION IS WIDESPREAD AND
STEADY...OR MORE SCATTERED AND SHOWERY IS STILL UNCERTAIN...BUT
THERE IS AT LEAST SOME POSSIBILITY FOR PORTIONS OF THE REGION TO
RECEIVE MEASURABLE SNOW SOMETIME DURING THIS PERIOD. FOR
TEMPS...EXPECT MINS WED NT TO MAINLY BE IN THE 30S...WITH THU MAXES
MAINLY IN THE 30S FOR HIGHER ELEVATIONS...AND 40S FOR VALLEYS. FOR
THU NT...EXPECT MINS TO FALL INTO THE 20S FOR HIGHER
ELEVATIONS...AND LOWER/MID 30S FOR THE VALLEYS...WITH FRI MAXES
RANGING FROM THE LOWER/MID 30S ACROSS HIGHER ELEVATIONS...TO THE
UPPER 30S/LOWER 40S WITHIN THE VALLEYS. IT MAY ALSO BECOME QUITE
WINDY BY FRI...DEPENDING ON THE EVOLUTION AND TRACK OF ANY SFC LOW
PASSING TO OUR E OR NE.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE REGION SATURDAY THROUGH
SUNDAY.
THE REST OF THIS AFTERNOON...MVFR/VFR CLOUD COVER WILL PREVAIL AT
ALB AND GFL AS MOISTURE OFF THE GREAT LAKES IS TRAPPED BELOW AN
INVERSION. THE EDGE OF THE CLOUDS WILL REMAIN NORTH OF KPOU...SO
JUST SCATTERED CLOUDS ABOVE 3000 FEET AT BEST. WINDS WILL BE
NORTHWEST AT KGFL...KALB AND KPOU AT 10 KT OR LESS.
TONIGHT...HIGH PRESSURE GRADUALLY BUILDS IN...AND BASED ON
SATELLITE TRENDS...CLEARING WILL BUILD FROM NORTH TO SOUTH THROUGH
THE NIGHT. CLEARING SHOULD BE AROUND 04Z AT GFL...AND 06Z AT KALB.
ONCE THE SKY SLEARS...AND WINDS REMAIN LIGHT...SOME PATCHY DENSE
FOG COULD FORM...ESPECIALLY AROUND KGFL...THROUGH SUNRISE.
WINDS WILL BE NEARLY CALM...BUT IN SOME AREAS LIGHT NORTH TO
NORTHWEST AT 5 KT OR LESS.
OUTLOOK...
SUN...VFR...NO SIG WX.
MON-TUE...VFR-MVFR...CHC OF RAIN.
WED-THU...VFR...CHC OF SHOWERS.
&&
.HYDROLOGY...
MOST RIVERS HAVE CRESTED AND ARE STARTING TO RECEDE OR WILL CREST
IN THE NEXT SEVERAL HOURS. RISES FROM THE RAIN THAT FELL THURSDAY
NIGHT INTO FRIDAY MORNING WERE GENERALLY 1 TO 2 FEET. AS HIGH
PRESSURE CONTINUES TO BUILD INTO THE REGION OVER THE
WEEKEND...WATER LEVELS WILL CONTINUE TO RECEDE IN MOST AREAS
THROUGH AT LEAST MONDAY. THE NEXT CHANCE FOR RAIN WILL BE LATE
MONDAY INTO TUESDAY MORNING...BUT ALLOT OF UNCERTAINTY EXISTS AT
THIS TIME WITH STORM TRACK AND QPF AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
AVIATION...NAS
000
FXUS61 KALY 211555
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
1055 AM EST SAT NOV 21 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL BUILD INTO NEW YORK
AND NEW ENGLAND THROUGH SUNDAY AND THEN LIFT NORTHEAST INTO THE
CANADIAN MARITIMES ON MONDAY. A LOW PRESSURE SYSTEM WILL THEN START
TO LIFT NORTHEAST FROM THE CAROLINA COAST MONDAY MORNING...AND PASS
SOUTHEAST OF LONG ISLAND TUESDAY MORNING...BRINGING UNSETTLED
WEATHER TO MUCH OF OUR REGION STARTING LATE MONDAY OR MONDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CLOUDS CONTINUE TO SPREAD ACROSS THE REGION AS LAKE EFFECT
MOISTURE GETS TRAPPED BENEATH A BOUNDARY LAYER INVERSION. AREAS
EAST OF THE SOUTHERN GREEN MOUNTAINS AND BERKSHIRES...WHERE SOME
DOWNSLOPE IS OCCURRING...ARE REMAINING PARTLY TO MOSTLY SUNNY.
INCREASING SKY COVER FOR MANY AREAS THIS AFTERNOON...BUT SOME
HINTS IN LATEST GUIDANCE THAT SOME AREAS MAY SEE THE CLOUDS BREAK
UP TO SOME DEGREE. SO...GOING MOSTLY CLOUDY IN MANY AREAS. BASED
ON CURRENT TEMPERATURES AND AREA 12Z SOUNDINGS...CURRENT MAX
TEMPERATURES LOOK IN THE BALL PARK. EVERYTHING ELSE UNTOUCHED.
PREV AFD BELOW...
CLOUDS WILL SLOWLY SHRINK ACROSS FA THIS
MORNING AS STRATO CU ASSOCIATED WITH UPPER LEVEL TROUGH SLIDE
THROUGH FA. LAKE RESPONSE HAS BEEN WEAK AT BEST AND WITH AIRMASS
NOT BEING VERY COLD EXPECT THAT LAKE INDUCED CLOUDS WILL ONLY
LINGER ACROSS PORTIONS OF WESTERN ADIRONDACKS AND MOHAWK VALLEY
INTO EARLY THIS AFTERNOON AND THEN START TO DISSIPATE. WILL KEEP
FORECAST DRY TODAY AND HAVE TEMPS IN MOST AREAS A FEW DEGREES
BELOW YESTERDAY WITH HIGHS GENERALLY IN THE MID 40S TO MID 50S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
RIDGE OF HIGH PRESSURE WILL BE CENTERED OVER FA LATE TONIGHT INTO
EARLY SUNDAY AND THEN START TO LIFT NORTHEAST INTO CANADA. THIS
WILL RESULT IN MAINLY CLEAR SKIES WITH SEASONABLE TEMPS TONIGHT
WITH LOWS IN THE MID 20S TO MID 30S.
ON SUNDAY EXPECT THAT TEMPS MAYBE A FEW DEGREES COOLER IN THE
VALLEYS THAN TODAY AS DESPITE NEARLY FULL SUN...ORIENTATION OF
HIGH WILL RESULT IN A WEAK LOW LEVEL EASTERLY FLOW AND MIXING WILL
BE POOR ONLY UP TO 925 MB. HIGHS ON SUNDAY IN THE UPPER 40S TO
LOWER 50S.
ON SUNDAY NIGHT EXPECT MAINLY CLEAR SKIES IN THE EVENING AND THEN
PARTLY CLOUDY CONDITIONS LATE AS HIGH CLOUDS START TO LIFT
NORTHWARD AHEAD OF NEXT SYSTEM. LOWS SHOULD BE SIMILAR TO SATURDAY
NIGHT IN THE MID 20S TO LOWER 30S.
MONDAY LOOKS TO BE THE TRANSITION DAY WITH UNCERTAINTY STILL ON
EXACT TRACK AND ORIENTATION OF PCPN SHIELD...GEM APPEARS TO BE
THE FASTEST AND WETTEST WITH NAM NOT FAR BEHIND AS BOTH HAVE
LEADING EDGE OF PCPN SHIELD AT LEAST NORTH OF I90 BEFORE 00Z TUE AND
QPF AMOUNTS OF A TENTH TO A QUARTER OF AN INCH ACROSS FA. WHILE GFS
AND ECMWF SIGNIFICANTLY SLOWER WITH ONLY LIGHT RAIN AND A FEW
HUNDREDTHS OF AN INCH OF QPF INTO SE THIRD OF FA BEFORE 00Z TUE.
FOR NOW WILL KEEP FORECAST DRY WITH INCREASING CLOUDS ON MONDAY
MORNING AND THEN HAVE SLIGHT CHANCE TO CHANCE POPS SOUTH OF I90
MONDAY AFTERNOON. HIGH TEMPS ON MONDAY EXPECTED TO BE IN THE MID
TO UPPER 40S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MON NT-TUE...STILL QUITE A BIT OF UNCERTAINTY REGARDING NEXT
SYSTEM...CURRENTLY DEVELOPING ALONG THE WESTERN GULF COAST. THE
GENERAL TREND IN THE MODELS OVER THE LAST 24 HOURS HAS BEEN
WEAKER...AND FURTHER S/E WITH THE TRACK. THE 00Z/21 GEM IS MOST
AGGRESSIVE WITH THIS FEATURE...TRACKING IT OFF THE NEW ENGLAND
COAST...BUT STILL FAR ENOUGH WEST TO BRING AT LEAST SOME LIGHT RAIN
TO THE S/E HALF OF REGION. THE 00Z/21 GFS IS A BIT FURTHER
S/E...WHILE THE 00Z/21 ECMWF AND AT LEAST HALF OF THE MREFS KEEP
MOST PRECIP OUT OF OUR REGION...JUST CLIPPING FAR SE AREAS LATE MON
NT INTO EARLY TUE. BASED ON THIS LINGERING UNCERTAINTY...HAVE
INDICATED ONLY SLIGHT CHC TO LOW CHC POPS FOR RAIN ACROSS SOUTHERN
HALF OF REGION...WHILE KEEPING NORTHERN AREAS DRY. AS FOR
TEMPS...GENERALLY FOLLOWED CLOSE TO GMOS...WITH MINS MAINLY IN THE
30S...AND TUE MAXES MAINLY IN THE UPPER 40S TO LOWER 50S. SHOULD THE
CLOUDS/PRECIP EXTEND FURTHER N/W...EVEN COOLER MAXES ARE POSSIBLE.
TUE NT-WED...WILL INDICATE DRY CONDITIONS DURING THIS PERIOD...AS
MOST MODELS HINT AT SHORTWAVE RIDGING BUILDING INTO THE REGION.
HOWEVER...BY LATE WED...ENERGY AND WARM ADVECTION APPROACHING FROM
THE W MAY LEAD TO SOME RAIN BY LATE WED. THUS...HAVE INDICATED SOME
SLIGHT CHC TO LOW CHC POPS ACROSS SW AREAS FOR LATE WED.
OTHERWISE...EXPECT MAX TEMPS TO RANGE FROM THE MID 40S ACROSS FAR
NORTHERN AREAS...TO THE LOWER/MID 50S ACROSS CENTRAL AND SOUTHERN
AREAS...WITH OVERNIGHT MINS TUE NT MAINLY IN THE MID/UPPER 30S.
WED NT-FRI...MODELS HINT AT ADDITIONAL PRECIP DURING THIS
PERIOD...ALTHOUGH DIFFER ON THE EXACT TRIGGERING MECHANISMS. THE
00Z/GFS HINTS AT A FASTER WAVE MOVING THROUGH LATE WED INTO WED NT
WITH RAIN...WHILE MOST MREF MEMBERS...AND THE ECMWF DEPICT A
SLIGHTLY SLOWER UPPER LEVEL SYSTEM DEVELOPING ACROSS THE GREAT
LAKES...WHILE ANOTHER SFC LOW DEVELOPS ALONG THE SE COAST AND TRACKS
NNE. AT THE VERY LEAST...WILL INDICATE CHC POPS DURING THIS PERIOD
FOR RAIN...ALTHOUGH SOME WET SNOW COULD BE MIXED IN ACROSS HIGHER
ELEVATIONS EARLY THU. THEN...AS MID/UPPER LEVEL CONTINUE TO
COOL...WE EXPECT ANY RAIN TO GRADUALLY MIX WITH/CHANGE TO SNOW
ACROSS HIGHER ELEVATIONS BY LATE THU...AND PERHAPS WITHIN VALLEYS BY
THU NT OR EARLY FRI. WHETHER THIS PRECIPITATION IS WIDESPREAD AND
STEADY...OR MORE SCATTERED AND SHOWERY IS STILL UNCERTAIN...BUT
THERE IS AT LEAST SOME POSSIBILITY FOR PORTIONS OF THE REGION TO
RECEIVE MEASURABLE SNOW SOMETIME DURING THIS PERIOD. FOR
TEMPS...EXPECT MINS WED NT TO MAINLY BE IN THE 30S...WITH THU MAXES
MAINLY IN THE 30S FOR HIGHER ELEVATIONS...AND 40S FOR VALLEYS. FOR
THU NT...EXPECT MINS TO FALL INTO THE 20S FOR HIGHER
ELEVATIONS...AND LOWER/MID 30S FOR THE VALLEYS...WITH FRI MAXES
RANGING FROM THE LOWER/MID 30S ACROSS HIGHER ELEVATIONS...TO THE
UPPER 30S/LOWER 40S WITHIN THE VALLEYS. IT MAY ALSO BECOME QUITE
WINDY BY FRI...DEPENDING ON THE EVOLUTION AND TRACK OF ANY SFC LOW
PASSING TO OUR E OR NE.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE REGION SATURDAY THROUGH
SUNDAY.
TODAY...MVFR LEVEL CLOUDS HAVE DEVELOPED AT KGFL AND KALB EARLY THIS
MORNING...AND WILL LIKELY CONTINUE THROUGH AT LEAST 15Z...BEFORE
RISING TO VFR LEVELS. HOWEVER...THERE IS SOME POSSIBILITY OF MVFR
CIGS PERSISTING EVEN LONGER. AT KPOU...EXPECT VFR CONDITIONS THROUGH
AT LEAST EARLY TONIGHT.
TONIGHT...CONFIDENCE DECREASING ON WHETHER ADDITIONAL LOW CLOUDS
REDEVELOP LATER TONIGHT...OR SKIES REMAIN CLEAR WITH PATCHY GROUND
FOG DEVELOPMENT. LATEST MODEL GUIDANCE HINTS AT POSSIBLE MVFR/IFR
CIGS DEVELOPING AT KGFL AND KALB AFTER 06Z/SUN. AT THIS TIME...DUE
TO LINGERING UNCERTAINTY...WE HAVE INDICATED FEW-SCT CLOUDS BELOW
1000 FT AGL AT KGFL AND KALB AFTER 08Z/SUN...BUT SHOULD MOISTENING
TRENDS CONTINUE IN MODEL GUIDANCE...WE MAY NEED TO CONSIDER SOME IFR
CIGS LATER TONIGHT AT THESE TERMINALS. AT KPOU...CONDITIONS SHOULD
REMAIN VFR...WITH PERHAPS SOME MVFR VSBYS DEVELOPING LATE DUE TO
PATCHY GROUND FOG.
WINDS WILL REMAIN FROM THE W TO NW AT 5-10 KT TODAY...BECOMING
LIGHT/VARIABLE TONIGHT. SOME GUSTINESS IS POSSIBLE THROUGH SAT
MORNING...ESP AT KALB...POSSIBLY REACHING 15-20 KT. IN ADDITION...AT
KGFL...SOME VARIATIONS IN WIND DIRECTION IS POSSIBLE THIS AFTERNOON
DUE TO LOCALIZED TOPOGRAPHICAL EFFECTS.
OUTLOOK...
SUN...VFR...NO SIG WX.
MON-TUE...VFR-MVFR...CHC OF RAIN.
WED...VFR...CHC OF SHOWERS.
&&
.HYDROLOGY...
MOST RIVERS HAVE CRESTED AND ARE STARTING TO RECEDE OR WILL CREST
IN THE NEXT SEVERAL HOURS. RISES FROM THE RAIN THAT FELL THURSDAY
NIGHT INTO FRIDAY MORNING WERE GENERALLY 1 TO 2 FEET. AS HIGH
PRESSURE CONTINUES TO BUILD INTO THE REGION OVER THE
WEEKEND...WATER LEVELS WILL CONTINUE TO RECEDE IN MOST AREAS
THROUGH AT LEAST MONDAY. THE NEXT CHANCE FOR RAIN WILL BE LATE
MONDAY INTO TUESDAY MORNING...BUT ALLOT OF UNCERTAINTY EXISTS AT
THIS TIME WITH STORM TRACK AND QPF AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...NAS
NEAR TERM...NAS
000
FXUS61 KBOX 211535
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
1035 AM EST SAT NOV 21 2009
.SYNOPSIS...
DRY AND PLEASANT WEATHER WILL CONTINUE THROUGH THIS WEEKEND WITH
HIGH PRESSURE IN PLACE. A WEAK LOW PRESSURE SYSTEM WILL APPROACH
SOUTHERN NEW ENGLAND FROM THE SOUTH MONDAY NIGHT AND TUESDAY. WEAK
HIGH PRESSURE WILL PROBABLY RESULT IN A DRY THANKSGIVING BEFORE A
POSSIBLE COASTAL STORM ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH CLOUDS CONTINUE TO STREAM ACROSS SOUTHERN NEW ENGLAND...WITH
MORE SUNSHINE FILTERING THROUGH. TEMPERATURES ARE ON TRACK WITH
EXISTING FORECAST...SO NO MAJOR CHANGES THERE. LIGHT WEST WINDS WILL
GRADUALLY SHIFT TO NORTH DURING THE DAY...BUT SHOULD NOT BE MUCH OF A
FACTOR.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
TONIGHT...FEEL THAT THE MID-HIGH CLOUDS WILL SHIFT NE AS THE CENTER
OF THE HIGH BUILDS INTO NORTHERN NEW ENGLAND. WITH THE RIDGE AXIS N
OF THE REGION...WILL SEE LIGHT WINDS WITH SOME NE COMPONENT ALONG
THE COAST. MAY SEE A FEW CLOUDS LINGERING...ALONG WITH SOME PATCHY
VALLEY FOG DEVELOPING LATE AT NIGHT. OVERNIGHT LOWS WILL BOTTOM OUT
IN THE 30S TO NEAR 40...WHICH IS STILL AROUND 5 DEGREES ABOVE
NORMAL.
SUNDAY...HIGH PRESSURE REMAINS ACROSS NORTHERN NEW ENGLAND...MEANING
ANOTHER MOSTLY SUNNY DAY. MAY SEE SOME CLOUDS DEVELOP ACROSS SE
MA/RI WITH THE NE FLOW. MODELS ARE HINTING AT AN INCREASE IN PRES
GRADIENT ACROSS SOUTHERN AREAS AND ESPECIALLY OVER THE COASTAL
WATERS. THIS MAY HELP BRING LOW LEVEL MOISTURE ONSHORE WITH SOME
CLOUD DEVELOPMENT. WITH THE COOLER ONSHORE FLOW IN PLACE...EXPECT
DAYTIME HIGHS TO RUN COOLER THAN TODAY BUT STILL SEVERAL DEGREES
ABOVE NORMAL...WITH THE COOLEST READINGS ALONG THE COAST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
CONFIDENCE IS BELOW AVERAGE DURING THIS PERIOD DUE TO SPREAD IN
MODEL SOLUTIONS AS WELL AS SOME RUN TO RUN DISCONTINUITY.
SEEING TENDENCY FOR VARIOUS MEDIUM RANGE MODELS TO PROJECT
MEASURABLE RAIN FOR MON NIGHT THRU TUE...AND THIS IS SUPPORTED BY
SREF PROBABILITIES. NOTICED THAT 00Z ECMWF IS WETTER THAN ITS PRIOR
RUN. THERE ARE TIMING AND QPF VARIATIONS AMONG THE MODELS.
THUS...HAVE NOT TRIED TO BE TOO PRECISE ON TIMING OF ONSET AND
ENDING OF POPS AND HAVE CAPPED AT HIGH CHANCE FOR NOW. SUSPECT MOST
LOCATIONS WILL GET MEASURABLE SOMETIME IN THE MON NIGHT TO TUE NIGHT
TIME FRAME BUT CANNOT PIN THE TIMING DOWN ANY BETTER. THE GLOBAL GEM
STILL LOOKS TOO ROBUST GIVEN THAT THIS SYSTEM IS ASSOCIATED WITH A
DAMPENING SHORT WAVE TROF MOVING INTO THE LONG WAVE RIDGE POSITION.
HOWEVER...AS WEAK AS SYSTEM IS...DOES LOOK LIKE DECENT OVERRUNNING
WITH A SUBTROPICAL MOISTURE SOURCE. AS FAR AS TIMING...AM SUSPICIOUS
THAT DRY LOW LEVEL AIR ASSOCIATED WITH MODERATELY STRONG HIGH PRES
CENTERED OVER NOVA SCOTIA AT THE OUTSET MAY DELAY THE SPREAD OF RAIN
INTO SOUTHWEST NH AND NORTHEAST MA MON NIGHT.
WED IS A LITTLE COMPLICATED WITH VIGOROUS NEGATIVE TILT SHORT WAVE
TROF ROTATING THROUGH THE GREAT LAKES. SOUTHERN NEW ENGLAND IS
FAIRLY WELL EAST OF SIGNIFICANT DYNAMICS. GFS DEPICTS SE FLOW THAT
COULD IN ITSELF CONTRIBUTE TO LOW CLOUDS AND DRIZZLE WHEREAS THE
ECMWF SHOWS LESS RH AND FLAT GRADIENT AMIDST WEAK SURFACE RIDGE.
HAVE GONE WITH SLIGHT CHANCE TO CHANCE POPS. TEMPERATURES MAY BE
TRICKY FOR WED GIVEN WARM AIR MASS ALOFT WITH 8+C 850 MB
TEMPERATURES BUT INVERSION MAY PREVENT REALIZING THE RELATIVE WARMTH
AT THE SURFACE. IF GET ENOUGH SUN...THEN WED MAX TEMPERATURES MAY
END UP CONSIDERABLY HIGHER THAN CURRENTLY FORECAST.
THANKSGIVING DAY CURRENTLY LOOKS DRY WITH PERHAPS A SUNNY START
BEFORE INCREASING CLOUDS DURING THE AFTERNOON AHEAD OF THE NEXT
SYSTEM. A VIGOROUS SHORT WAVE TROF HELPS INITIATE A COASTAL LOW BUT
AGAIN MEDIUM MODELS NOT IN GOOD AGREEMENT IN HANDLING THIS SYSTEM
WITH REGARD TO INTENSITY AND TRACK. HAVE GONE WITH CHC POPS THU
NIGHT AND FRI. AIR MASS MAY COOL SUFFICIENTLY TOWARD BACK PART OF
STORM TO CAUSE PTYPE UNCERTAINTY. POTENTIAL FOR RAIN TO MIX WITH OR
CHANGE TO SNOW OVER THE HIGHER ELEVATIONS OF OUR NW ZONES ON FRI BUT
CONFIDENCE OF THIS ACTUALLY OCCURRING IS CURRENTLY LOW.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
TODAY...VFR.
TONIGHT...VFR. PATCHY FOG WITH BRIEF MVFR CIGS/VSBYS LATE AT NIGHT
IN THE NORMALLY SUSCEPTIBLE VALLEYS.
SUNDAY...VFR. MAY SEE PATCHY VFR TO LOCAL MVFR CIGS ALONG THE COAST
DURING THE LATE MORNING/AFTERNOON.
OUTLOOK /SUNDAY NIGHT THROUGH WEDNESDAY/...
MON THRU WED...VFR MON BECOMING MVFR WITH AREAS IFR IN RAIN AND FOG
MON NIGHT THROUGH TUE NIGHT. MVFR CIGS MAY PERSIST INTO WED.
&&
.MARINE...
TODAY...SMALL CRAFT ADVISORY WILL LIKELY BE DROPPED AT 11 AM. WANT TO
GET ONE MORE ROUND OF BUOY REPORTS TO BE SURE. WINDS ARE NOT THE
CONCERN AT THIS POINT...BUT THE LINGERING ROUGH SEAS ACROSS THE OUTER
COASTAL WATERS.
TONIGHT...HIGH PRES BUILDING N OF THE WATERS. EXPECT N-NE WINDS AT
15 KT OR LESS WITH SEAS 4 FT OR LESS.
SUNDAY...NE FLOW SLOWLY INCREASES...WITH GUSTS UP TO 20 KT. EXPECT
HIGHEST WINDS E AND S OF NANTUCKET. FOR NOW...HAVE FORECASTED SEAS
AT 4 FT OR LESS...BUT MAY BUILD WITH THE NE FLOW ON THE OPEN OUTER
WATERS.
OUTLOOK /MONDAY THROUGH WEDNESDAY/...
PERSISTENT E GRADIENT WITH CONSIDERABLE FETCH WILL LIKELY KEEP SEAS
NEAR OR ABOVE 5 FT EXPOSED COASTAL WATERS MON NIGHT THRU WED MORNING AND
MAY BE STRONG ENOUGH TO MEET SCA WIND THRESHOLDS OVER MOST OF WATERS.
RESPITE LIKELY LATE WED THRU THU BEFORE RISK OF POTENT COASTAL LOW PRES
SYSTEM TOWARD END OF WEEK.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EST THIS MORNING FOR ANZ250-
254>256.
&&
$$
SYNOPSIS...EVT/THOMPSON
NEAR TERM...BELK/EVT
SHORT TERM...EVT
LONG TERM...THOMPSON
AVIATION...BELK/EVT/THOMPSON
MARINE...EVT/RLG/THOMPSON
000
FXUS61 KOKX 211137
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
637 AM EST SAT NOV 21 2009
.SYNOPSIS...
HIGH PRESSURE SLOWLY BUILDS INTO THE NORTHEASTERN UNITED STATES
THROUGH SUNDAY...THEN SLOWLY RETREATS INTO THE CANADIAN MARITIME
PROVINCES THROUGH EARLY NEXT WEEK. MEANWHILE...AN AREA OF LOW
PRESSURE WILL MOVE UP THE SOUTHEAST COAST MONDAY...THEN CONTINUE
NORTHEAST TO A POSITION EAST OF CAPE COD BY WEDNESDAY MORNING.
WEAK HIGH PRESSURE BUILDS IN FROM THE NORTH WEDNESDAY. ANOTHER
STORM SYSTEM WILL THEN IMPACT THE TRI-STATE TO CLOSE THE UPCOMING
WORK WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A 700 HPA AND 500 HPA TROUGH MOVING ACROSS THE TRI-STATE WILL
PRODUCE SOME SCATTERED TO OCCASIONALLY BROKEN MID TO HIGH CLOUDS
ACROSS THE REGION TODAY. SUBSIDENCE FROM THE SURFACE HIGH
BUILDING IN WILL LIMIT MIXING TO AROUND 925 HPA...THIS COUPLED
WITH THE AFOREMENTIONED CLOUD COVER WILL PRODUCE HIGHS MAINLY IN
THE MID TO UPPER 50S (ABOUT 5 DEGREES ABOVE NORMAL AND CONSISTENT
WITH A MAV/MET BLEND).
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
RIDGING BUILDING IN FROM 700 HPA TO THE SURFACE SHOULD CREATE
ENOUGH SUBSIDENCE FOR MAINLY CLEAR SKY CONDITIONS TONIGHT...AND
ALLOW FOR DECOUPLING OF THE BOUNDARY LAYER TO PRODUCE LIGHT WINDS
AT THE SURFACE. AS A RESULT SHOULD HAVE DECENT R ADIATIONAL
COOLING TONIGHT...WITH LOWS IN THE 30S (AROUND 40-MID 40S NYC
METRO). THESE VALUES ARE NEAR NORMAL...EXCEPT 3-5 DEGREES ABOVE
NORMAL IN THE NYC METRO AND FOLLOWED COOLER MET GUIDANCE (MAV TOO
WARM GIVEN EXPECTED RADIATIONAL COOLING AND RELATIVELY SHALLOW
NATURE OF COLD AIR MOVING IN).
DEEP LAYER RIDGING BUILDS IN SUNDAY...LIMITING MIXING TO AROUND
950 HPA AND MINIMIZING ANY CLOUD COVER. SO EVEN WITH ABUNDANT
SUNSHINE...WILL ONLY HAVE HIGHS AROUND 50 - OR NEAR NORMAL FOR
THIS TIME OF YEAR).
RIDGE AXIS SLIDES OFFSHORE SUNDAY NIGHT...ALLOWING FOR ONSHORE
FLOW TO SET UP...BUT DAMMING SURFACE HIGH WILL CONTINUE LOW LEVEL
COLD ADVECTION...AS A RESULT WILL END UP SEEING LOWS A COUPLE OF
DEGREES COOLER THAN TONIGHT (ONCE AGAIN USED COOLER MET
GUIDANCE).
GFS AND ECMWF HAVE A FLATTER BASE TO THE SURFACE RIDGE THAN DO
THE NAM/CMC GGEM MONDAY-MONDAY NIGHT. THIS DIFFERENCE ALLOWS FOR
LOW LEVEL MOISTURE TO GET FURTHER INLAND IN THE GFS/ECMWF THAN IN
THE NAM/GGEM. THE SREF SUPPORTS THE STRUCTURE OF THE GFS/ECMWF SO
HAVE OPTED FOR A GFS/ECMWF BLEND FOR THE REMAINDER OF THE SHORT
TERM.
WITH OVER RUNNING SETTING UP ACROSS THE ENTIRE TRI-STATE MONDAY
AFTERNOON BRING CHANCE POPS TO ALL AREAS BY LATE AFTERNOON AND
CONTINUE MONDAY NIGHT. BETTER CHANCE OF RAIN MONDAY NIGHT WITH
500 AND 700 HPA SHORTWAVES CROSSING THE AREA AS WELL. FOR
TEMPERATURES USED MET/MAV BLEND MONDAY AND MEX/MEX ENSEMBLE MEAN
BLEND MONDAY NIGHT...WITH HIGHS NEAR NORMAL ON MONDAY AND 4-8
DEGREES ABOVE NORMAL MONDAY NIGHT (CLOUD COVER/RAIN LIMITING
DIURNAL RANGE).
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
LOW CONFIDENCE FORECAST IN THE EXTENDED WITH ALL THE MODELS
SHOWING SOMETHING DIFFERENT. GGEM IS MOST PROGRESSIVE WITH
COASTAL LOW FOR TUESDAY...GEFS SLOWEST AND MOST SUPPRESSED TO THE
SOUTH (LIKE YESTERDAY/S 12Z ECMWF) AND GFS AND ECMWF IN BETWEEN
(WITH ECMWF MORE PROGRESSIVE THAN THE GFS).
FOR THE NEXT SYSTEM MOVING THROUGH THE GREAT LAKES INTO THE
NORTHEAST DURING THE MIDDLE TO LATE PART OF NEXT WEEK. THE GFS
MAINTAINS TWO DISTINCT CUTOFF LOWS (ACTUALLY LINKING THE FIRST
ONE WHICH IT HAS PASSING TO OUR NW WEDNESDAY WITH THE DEPARTING
STORM SYSTEM EARLY THIS WEEK)...WHILE THE ECMWF ABSORBS THE
SECOND CHUNK OF UPPER LEVEL ENERGY INTO THE FIRST CUTOFF LOW WITH
THIS LOW SLOWLY CROSSING THE NE LATE NEXT WEEK. THE GGEM
MAINTAINS TWO DISTINCT CIRCULATIONS WITHOUT ANY PHASING...BUT
DOES SUGGEST BY LOOKING AT THE INDIVIDUAL SYSTEMS THAT THE ECMWF
SOLUTION IS PLAUSIBLE. FOR NOW HAVE OPTED FOR A GFS/ECMWF BLEND
IN THE EXTENDED...BUT AS NOTED IN THE FIRST SENTENCE OF THE FIRST
PARAGRAPH...THIS IS A LOW CONFIDENCE FORECAST...SO EXPECT
CHANGES.
APPEARS FOR NOW THAT RAIN WILL LINGER INTO TUESDAY...THEN TAPER
OFF TUESDAY EVENING AS COASTAL LOW DEPARTS (CHANCE POPS TUESDAY
AND SLIGHT CHANCE POPS TUESDAY NIGHT). WHILE THERE IS SOME
SUGGESTION WEDNESDAY WILL END UP DRY WITH HIGH PRESSURE BUILDING
IN...IF GFS ENDS UP BEING RIGHT....COULD SEE SOME LIGHT SHOWERS
WEDNESDAY...SO SLIGHT CHANCE POPS. ON THE FLIP SIDE...GFS WOULD
HAVE THINGS DRY WEDNESDAY NIGHT/THURSDAY...BUT ECMWF BRINGS IN
PRECIPITATION AHEAD OF CONSOLIDATED CUTOFF...SO HAVE SLIGHT
CHANCE POPS BOTH PERIODS. BOTH MODELS SUGGEST RAIN FROM CUTOFF
LOW THURSDAY NIGHT/FRIDAY (POSSIBLY MIXED WITH/CHANGING TO SNOW
N/W OF NYC DEPENDING ON EXACT TRACK OF CUTOFF LOW AND HOW MUCH
LOW LEVEL COLD AIR ACTUALLY ENDS UP MOVING IN WITH IT)...SO
CHANCE POPS.
FOR TEMPERATURES USED A MEX/MEX ENSEMBLE MEAN BLEND WITH THE HIGH
MEMBER OF THE MEX ENSEMBLE MEAN BLENDED IN WEDNESDAY NIGHT-
THURSDAY NIGHT TO REFLECT WARMER ECMWF SOLUTION AT THOSE TIMES.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
VFR THROUGH THE DAY TODAY AS HIGH PRESSURE BUILDS TOWARD THE
AREA AND INTO SOUTHEASTERN CANADA AND NORTHERN NEW ENGLAND
TONIGHT. WEST WINDS UNDER 10 KT EARLY THIS MORNING WILL VEER TO
THE NORTHWEST...320...FROM MID MORNING THROUGH THE AFTERNOON AND
LIKELY REMAIN UNDER 10 KT. THE WINDS VEER FURTHER TO THE NORTH TO
NORTH NORTHEAST...360 TO 020...TONIGHT AND INCREASE SOMEWHAT AS
THE HIGH BUILDS TO THE NORTH.
OUTLOOK 12Z SUNDAY THROUGH WEDNESDAY...
SUN-MON MORNING: VFR.
MON AFTERNOON-TUE: SUB-VFR LIKELY IN SHOWERS.
TUE NIGHT: BECOMING VFR.
WED...MOST LIKELY VFR.
&&
.MARINE...
HIGH PRESSURE BUILDING INTO THE AREA WATERS TODAY RESULTS IN WEST
TO NORTHWEST WINDS. WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS. THE HIGH BUILDS INTO SOUTHEASTERN CANADA AND
NORTHERN NEW ENGLAND TONIGHT AND SUNDAY AND STRENGTHENS. WINDS
SHIFT TO THE NORTH THE TO THE NORTHEAST. SUNDAY NIGHT AND MONDAY
THE HIGH CONTINUES TO STRENGTHEN...THERE IS ALSO THE POTENTIAL
FOR A COASTAL LOW TO MOVE INTO THE HIGH. THIS WILL INCREASE THE
WINDS...GUSTS...AND SEAS ACROSS THE AREA WITH SMALL CRAFT
CONDITIONS BECOMING LIKELY BY SUNDAY NIGHT. WINDS COULD DROP
BELOW SMALL CRAFT LEVELS TUESDAY AS THE FORECAST WATERS ARE
BETWEEN TWO LOW PRESSURE SYSTEMS. ANOTHER LOW MAY APPROACH FROM
THE WEST DURING TUESDAY AND INTO WEDNESDAY. THERE IS SOME
UNCERTAINTY TO THE TRACK AND TIMING OF THE LOW AT THIS TIME. SEAS
ON THE OCEAN WILL LIKELY REMAIN AT SMALL CRAFT LEVELS INTO
WEDNESDAY.
&&
.HYDROLOGY...
DRY THROUGH MONDAY MORNING. A QUARTER TO A HALF AN INCH OF
RAINFALL IS POSSIBLE MONDAY AFTERNOON THROUGH TUESDAY WITH
LOCALLY HIGHER AMOUNTS WITHIN THE REASONABLE REALM OF
POSSIBILITIES. MORE PRECIPITATION IS EXPECTED TOWARDS THE END OF
NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...PFM
NEAR TERM...PFM
SHORT TERM...PFM
LONG TERM...PFM
AVIATION...MET
MARINE...BG/PFM
HYDROLOGY...BG/PFM
000
FXUS61 KALY 211119
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
613 AM EST SAT NOV 21 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL BUILD INTO NEW YORK
AND NEW ENGLAND THROUGH SUNDAY AND THEN LIFT NORTHEAST INTO THE
CANADIAN MARITIMES ON MONDAY. A LOW PRESSURE SYSTEM WILL THEN START
TO LIFT NORTHEAST FROM THE CAROLINA COAST MONDAY MORNING...AND PASS
SOUTHEAST OF LONG ISLAND TUESDAY MORNING...BRINGING UNSETTLED
WEATHER TO MUCH OF OUR REGION STARTING LATE MONDAY OR MONDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CLOUDS WILL SLOWLY SHRINK ACROSS FA THIS MORNING AS STRATO CU
ASSOCIATED WITH UPPER LEVEL TROUGH SLIDE THROUGH FA. LAKE RESPONSE
HAS BEEN WEAK AT BEST AND WITH AIRMASS NOT BEING VERY COLD EXPECT
THAT LAKE INDUCED CLOUDS WILL ONLY LINGER ACROSS PORTIONS OF
WESTERN ADIRONDACKS AND MOHAWK VALLEY INTO EARLY THIS AFTERNOON
AND THEN START TO DISSIPATE. WILL KEEP FORECAST DRY TODAY AND HAVE
TEMPS IN MOST AREAS A FEW DEGREES BELOW YESTERDAY WITH HIGHS
GENERALLY IN THE MID 40S TO MID 50S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
RIDGE OF HIGH PRESSURE WILL BE CENTERED OVER FA LATE TONIGHT INTO
EARLY SUNDAY AND THEN START TO LIFT NORTHEAST INTO CANADA. THIS
WILL RESULT IN MAINLY CLEAR SKIES WITH SEASONABLE TEMPS TONIGHT
WITH LOWS IN THE MID 20S TO MID 30S.
ON SUNDAY EXPECT THAT TEMPS MAYBE A FEW DEGREES COOLER IN THE
VALLEYS THAN TODAY AS DESPITE NEARLY FULL SUN...ORIENTATION OF
HIGH WILL RESULT IN A WEAK LOW LEVEL EASTERLY FLOW AND MIXING WILL
BE POOR ONLY UP TO 925 MB. HIGHS ON SUNDAY IN THE UPPER 40S TO
LOWER 50S.
ON SUNDAY NIGHT EXPECT MAINLY CLEAR SKIES IN THE EVENING AND THEN
PARTLY CLOUDY CONDITIONS LATE AS HIGH CLOUDS START TO LIFT
NORTHWARD AHEAD OF NEXT SYSTEM. LOWS SHOULD BE SIMILAR TO SATURDAY
NIGHT IN THE MID 20S TO LOWER 30S.
MONDAY LOOKS TO BE THE TRANSITION DAY WITH UNCERTAINTY STILL ON
EXACT TRACK AND ORIENTATION OF PCPN SHIELD...GEM APPEARS TO BE
THE FASTEST AND WETTEST WITH NAM NOT FAR BEHIND AS BOTH HAVE
LEADING EDGE OF PCPN SHIELD AT LEAST NORTH OF I90 BEFORE 00Z TUE AND
QPF AMOUNTS OF A TENTH TO A QUARTER OF AN INCH ACROSS FA. WHILE GFS
AND ECMWF SIGNIFICANTLY SLOWER WITH ONLY LIGHT RAIN AND A FEW
HUNDREDTHS OF AN INCH OF QPF INTO SE THIRD OF FA BEFORE 00Z TUE.
FOR NOW WILL KEEP FORECAST DRY WITH INCREASING CLOUDS ON MONDAY
MORNING AND THEN HAVE SLIGHT CHANCE TO CHANCE POPS SOUTH OF I90
MONDAY AFTERNOON. HIGH TEMPS ON MONDAY EXPECTED TO BE IN THE MID
TO UPPER 40S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MON NT-TUE...STILL QUITE A BIT OF UNCERTAINTY REGARDING NEXT
SYSTEM...CURRENTLY DEVELOPING ALONG THE WESTERN GULF COAST. THE
GENERAL TREND IN THE MODELS OVER THE LAST 24 HOURS HAS BEEN
WEAKER...AND FURTHER S/E WITH THE TRACK. THE 00Z/21 GEM IS MOST
AGGRESSIVE WITH THIS FEATURE...TRACKING IT OFF THE NEW ENGLAND
COAST...BUT STILL FAR ENOUGH WEST TO BRING AT LEAST SOME LIGHT RAIN
TO THE S/E HALF OF REGION. THE 00Z/21 GFS IS A BIT FURTHER
S/E...WHILE THE 00Z/21 ECMWF AND AT LEAST HALF OF THE MREFS KEEP
MOST PRECIP OUT OF OUR REGION...JUST CLIPPING FAR SE AREAS LATE MON
NT INTO EARLY TUE. BASED ON THIS LINGERING UNCERTAINTY...HAVE
INDICATED ONLY SLIGHT CHC TO LOW CHC POPS FOR RAIN ACROSS SOUTHERN
HALF OF REGION...WHILE KEEPING NORTHERN AREAS DRY. AS FOR
TEMPS...GENERALLY FOLLOWED CLOSE TO GMOS...WITH MINS MAINLY IN THE
30S...AND TUE MAXES MAINLY IN THE UPPER 40S TO LOWER 50S. SHOULD THE
CLOUDS/PRECIP EXTEND FURTHER N/W...EVEN COOLER MAXES ARE POSSIBLE.
TUE NT-WED...WILL INDICATE DRY CONDITIONS DURING THIS PERIOD...AS
MOST MODELS HINT AT SHORTWAVE RIDGING BUILDING INTO THE REGION.
HOWEVER...BY LATE WED...ENERGY AND WARM ADVECTION APPROACHING FROM
THE W MAY LEAD TO SOME RAIN BY LATE WED. THUS...HAVE INDICATED SOME
SLIGHT CHC TO LOW CHC POPS ACROSS SW AREAS FOR LATE WED.
OTHERWISE...EXPECT MAX TEMPS TO RANGE FROM THE MID 40S ACROSS FAR
NORTHERN AREAS...TO THE LOWER/MID 50S ACROSS CENTRAL AND SOUTHERN
AREAS...WITH OVERNIGHT MINS TUE NT MAINLY IN THE MID/UPPER 30S.
WED NT-FRI...MODELS HINT AT ADDITIONAL PRECIP DURING THIS
PERIOD...ALTHOUGH DIFFER ON THE EXACT TRIGGERING MECHANISMS. THE
00Z/GFS HINTS AT A FASTER WAVE MOVING THROUGH LATE WED INTO WED NT
WITH RAIN...WHILE MOST MREF MEMBERS...AND THE ECMWF DEPICT A
SLIGHTLY SLOWER UPPER LEVEL SYSTEM DEVELOPING ACROSS THE GREAT
LAKES...WHILE ANOTHER SFC LOW DEVELOPS ALONG THE SE COAST AND TRACKS
NNE. AT THE VERY LEAST...WILL INDICATE CHC POPS DURING THIS PERIOD
FOR RAIN...ALTHOUGH SOME WET SNOW COULD BE MIXED IN ACROSS HIGHER
ELEVATIONS EARLY THU. THEN...AS MID/UPPER LEVEL CONTINUE TO
COOL...WE EXPECT ANY RAIN TO GRADUALLY MIX WITH/CHANGE TO SNOW
ACROSS HIGHER ELEVATIONS BY LATE THU...AND PERHAPS WITHIN VALLEYS BY
THU NT OR EARLY FRI. WHETHER THIS PRECIPITATION IS WIDESPREAD AND
STEADY...OR MORE SCATTERED AND SHOWERY IS STILL UNCERTAIN...BUT
THERE IS AT LEAST SOME POSSIBILITY FOR PORTIONS OF THE REGION TO
RECEIVE MEASURABLE SNOW SOMETIME DURING THIS PERIOD. FOR
TEMPS...EXPECT MINS WED NT TO MAINLY BE IN THE 30S...WITH THU MAXES
MAINLY IN THE 30S FOR HIGHER ELEVATIONS...AND 40S FOR VALLEYS. FOR
THU NT...EXPECT MINS TO FALL INTO THE 20S FOR HIGHER
ELEVATIONS...AND LOWER/MID 30S FOR THE VALLEYS...WITH FRI MAXES
RANGING FROM THE LOWER/MID 30S ACROSS HIGHER ELEVATIONS...TO THE
UPPER 30S/LOWER 40S WITHIN THE VALLEYS. IT MAY ALSO BECOME QUITE
WINDY BY FRI...DEPENDING ON THE EVOLUTION AND TRACK OF ANY SFC LOW
PASSING TO OUR E OR NE.
&&
.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE REGION SATURDAY THROUGH
SUNDAY.
TODAY...MVFR LEVEL CLOUDS HAVE DEVELOPED AT KGFL AND KALB EARLY THIS
MORNING...AND WILL LIKELY CONTINUE THROUGH AT LEAST 15Z...BEFORE
RISING TO VFR LEVELS. HOWEVER...THERE IS SOME POSSIBILITY OF MVFR
CIGS PERSISTING EVEN LONGER. AT KPOU...EXPECT VFR CONDITIONS THROUGH
AT LEAST EARLY TONIGHT.
TONIGHT...CONFIDENCE DECREASING ON WHETHER ADDITIONAL LOW CLOUDS
REDEVELOP LATER TONIGHT...OR SKIES REMAIN CLEAR WITH PATCHY GROUND
FOG DEVELOPMENT. LATEST MODEL GUIDANCE HINTS AT POSSIBLE MVFR/IFR
CIGS DEVELOPING AT KGFL AND KALB AFTER 06Z/SUN. AT THIS TIME...DUE
TO LINGERING UNCERTAINTY...WE HAVE INDICATED FEW-SCT CLOUDS BELOW
1000 FT AGL AT KGFL AND KALB AFTER 08Z/SUN...BUT SHOULD MOISTENING
TRENDS CONTINUE IN MODEL GUIDANCE...WE MAY NEED TO CONSIDER SOME IFR
CIGS LATER TONIGHT AT THESE TERMINALS. AT KPOU...CONDITIONS SHOULD
REMAIN VFR...WITH PERHAPS SOME MVFR VSBYS DEVELOPING LATE DUE TO
PATCHY GROUND FOG.
WINDS WILL REMAIN FROM THE W TO NW AT 5-10 KT TODAY...BECOMING
LIGHT/VARIABLE TONIGHT. SOME GUSTINESS IS POSSIBLE THROUGH SAT
MORNING...ESP AT KALB...POSSIBLY REACHING 15-20 KT. IN ADDITION...AT
KGFL...SOME VARIATIONS IN WIND DIRECTION IS POSSIBLE THIS AFTERNOON
DUE TO LOCALIZED TOPOGRAPHICAL EFFECTS.
OUTLOOK...
SUN...VFR...NO SIG WX.
MON-TUE...VFR-MVFR...CHC OF RAIN.
WED...VFR...CHC OF SHOWERS.
&&
.HYDROLOGY...
MOST RIVERS HAVE CRESTED AND ARE STARTING TO RECEDE OR WILL CREST
IN THE NEXT SEVERAL HOURS. RISES FROM THE RAIN THAT FELL THURSDAY
NIGHT INTO FRIDAY MORNING WERE GENERALLY 1 TO 2 FEET. AS HIGH
PRESSURE CONTINUES TO BUILD INTO THE REGION OVER THE
WEEKEND...WATER LEVELS WILL CONTINUE TO RECEDE IN MOST AREAS
THROUGH AT LEAST MONDAY. THE NEXT CHANCE FOR RAIN WILL BE LATE
MONDAY INTO TUESDAY MORNING...BUT ALLOT OF UNCERTAINTY EXISTS AT
THIS TIME WITH STORM TRACK AND QPF AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...11
NEAR TERM...11
SHORT TERM...11
LONG TERM...KL
AVIATION...KL
HYDROLOGY...11
000
FXUS61 KBOX 210958
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
458 AM EST SAT NOV 21 2009
.SYNOPSIS...
DRY AND PLEASANT WEATHER WILL CONTINUE THROUGH THIS WEEKEND WITH
HIGH PRESSURE IN PLACE. A WEAK LOW PRESSURE SYSTEM WILL APPROACH
SOUTHERN NEW ENGLAND FROM THE SOUTH MONDAY NIGHT AND TUESDAY. WEAK
HIGH PRESSURE WILL PROBABLY RESULT IN A DRY THANKSGIVING BEFORE A
POSSIBLE COASTAL STORM ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ONLY A FEW PATCHES OF HIGH CLOUDS REMAIN OVER THE REGION AT 08Z...
FOR NOW. NOTING ANOTHER AREA OF MID-HIGH CLOUDS ACROSS NY/PA/NJ ON
THE IR SATELLITE LOOP...HEADING E IN THE WESTERLY UPPER FLOW.
WITH HIGH PRES BUILDING ACROSS NY INTO WESTERN NEW ENGLAND DURING
THE DAY...THE MID-HIGH CLOUDS WILL BE THE ONLY FLY IN THE OINTMENT
TODAY...WHICH WILL FILTER THE SUN SOMEWHAT. LIGHT WEST WINDS WILL
GRADUALLY SHIFT TO NORTH DURING THE DAY...BUT NOT MUCH OF A FACTOR.
WITH THE PLEASANT WEATHER AND NOT MUCH IN THE WAY OF COLD AIR
ADVECTION...EXPECT TEMPS TO REBOUND TO THE 50S ONCE AGAIN
TODAY...UPWARDS TO 10 DEGREES ABOVE NORMAL FOR LATE NOVEMBER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
TONIGHT...FEEL THAT THE MID-HIGH CLOUDS WILL SHIFT NE AS THE CENTER
OF THE HIGH BUILDS INTO NORTHERN NEW ENGLAND. WITH THE RIDGE AXIS N
OF THE REGION...WILL SEE LIGHT WINDS WITH SOME NE COMPONENT ALONG
THE COAST. MAY SEE A FEW CLOUDS LINGERING...ALONG WITH SOME PATCHY
VALLEY FOG DEVELOPING LATE AT NIGHT. OVERNIGHT LOWS WILL BOTTOM OUT
IN THE 30S TO NEAR 40...WHICH IS STILL AROUND 5 DEGREES ABOVE
NORMAL.
SUNDAY...HIGH PRESSURE REMAINS ACROSS NORTHERN NEW ENGLAND...MEANING
ANOTHER MOSTLY SUNNY DAY. MAY SEE SOME CLOUDS DEVELOP ACROSS SE
MA/RI WITH THE NE FLOW. MODELS ARE HINTING AT AN INCREASE IN PRES
GRADIENT ACROSS SOUTHERN AREAS AND ESPECIALLY OVER THE COASTAL
WATERS. THIS MAY HELP BRING LOW LEVEL MOISTURE ONSHORE WITH SOME
CLOUD DEVELOPMENT. WITH THE COOLER ONSHORE FLOW IN PLACE...EXPECT
DAYTIME HIGHS TO RUN COOLER THAN TODAY BUT STILL SEVERAL DEGREES
ABOVE NORMAL...WITH THE COOLEST READINGS ALONG THE COAST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
CONFIDENCE IS BELOW AVERAGE DURING THIS PERIOD DUE TO SPREAD IN
MODEL SOLUTIONS AS WELL AS SOME RUN TO RUN DISCONTINUITY.
SEEING TENDENCY FOR VARIOUS MEDIUM RANGE MODELS TO PROJECT
MEASURABLE RAIN FOR MON NIGHT THRU TUE...AND THIS IS SUPPORTED BY
SHREF PROBABILITIES. NOTICED THAT 00Z ECMWF IS WETTER THAN ITS PRIOR
RUN. THERE ARE TIMING AND QPF VARIATIONS AMONG THE MODELS.
THUS...HAVE NOT TRIED TO BE TOO PRECISE ON TIMING OF ONSET AND
ENDING OF POPS AND HAVE CAPPED AT HIGH CHANCE FOR NOW. SUSPECT MOST
LOCATIONS WILL GET MEASURABLE SOMETIME IN THE MON NIGHT TO TUE NIGHT
TIME FRAME BUT CANNOT PIN THE TIMING DOWN ANY BETTER. THE GLOBAL GEM
STILL LOOKS TOO ROBUST GIVEN THAT THIS SYSTEM IS ASSOCIATED WITH A
DAMPENING SHORT WAVE TROF MOVING INTO THE LONG WAVE RIDGE POSITION.
HOWEVER...AS WEAK AS SYSTEM IS...DOES LOOK LIKE DECENT OVERRUNNING
WITH A SUBTROPICAL MOISTURE SOURCE. AS FAR AS TIMING...AM SUSPICIOUS
THAT DRY LOW LEVEL AIR ASSOCIATED WITH MODERATELY STRONG HIGH PRES
CENTERED OVER NOVA SCOTIA AT THE OUTSET MAY DELAY THE SPREAD OF RAIN
INTO SOUTHWEST NH AND NORTHEAST MA MON NIGHT.
WED IS A LITTLE COMPLICATED WITH VIGOROUS NEGATIVE TILT SHORT WAVE
TROF ROTATING THROUGH THE GREAT LAKES. SOUTHERN NEW ENGLAND IS
FAIRLY WELL EAST OF SIGNIFICANT DYNAMICS. GFS DEPICTS SE FLOW THAT
COULD IN ITSELF CONTRIBUTE TO LOW CLOUDS AND DRIZZLE WHEREAS THE
ECMWF SHOWS LESS RH AND FLAT GRADIENT AMIDST WEAK SURFACE RIDGE.
HAVE GONE WITH SLIGHT CHANCE TO CHANCE POPS. TEMPERATURES MAY BE
TRICKY FOR WED GIVEN WARM AIR MASS ALOFT WITH 8+C 850 MB
TEMPERATURES BUT INVERSION MAY PREVENT REALIZING THE RELATIVE WARMTH
AT THE SURFACE. IF GET ENOUGH SUN...THEN WED MAX TEMPERATURES MAY
END UP CONSIDERABLY HIGHER THAN CURRENTLY FORECAST.
THANKSGIVING DAY CURRENTLY LOOKS DRY WITH PERHAPS A SUNNY START
BEFORE INCREASING CLOUDS DURING THE AFTERNOON AHEAD OF THE NEXT
SYSTEM. A VIGOROUS SHORT WAVE TROF HELPS INITIATE A COASTAL LOW BUT
AGAIN MEDIUM MODELS NOT IN GOOD AGREEMENT IN HANDLING THIS SYSTEM
WITH REGARD TO INTENSITY AND TRACK. HAVE GONE WITH CHC POPS THU
NIGHT AND FRI. AIR MASS MAY COOL SUFFICIENTLY TOWARD BACK PART OF
STORM TO CAUSE PTYPE UNCERTAINTY. POTENTIAL FOR RAIN TO MIX WITH OR
CHANGE TO SNOW OVER THE HIGHER ELEVATIONS OF OUR NW ZONES ON FRI BUT
CONFIDENCE OF THIS ACTUALLY OCCURRING IS CURRENTLY LOW.
&&
.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
TODAY...VFR.
TONIGHT...VFR. PATCHY FOG WITH BRIEF MVFR CIGS/VSBYS LATE AT NIGHT
IN THE NORMALLY SUSCEPTIBLE VALLEYS.
SUNDAY...VFR. MAY SEE PATCHY VFR TO LOCAL MVFR CIGS ALONG THE COAST
DURING THE LATE MORNING/AFTERNOON.
OUTLOOK /SUNDAY NIGHT THROUGH WEDNESDAY/...
MON THRU WED...VFR MON BECOMING MVFR WITH AREAS IFR IN RAIN AND FOG
MON NIGHT THROUGH TUE NIGHT. MVFR CIGS MAY PERSIST INTO WED.
&&
.MARINE...
TODAY...CONTINUED SMALL CRAFT MAINLY FOR SEAS ACROSS THE OUTER
WATERS. OFFSHORE BUOYS STILL REPORTING SWELLS AT 5-6 FT. ONLY KEPT
IT GOING FOR THE MORNING FOR NOW. WINDS WILL CONTINUE TO DIMINISH AS
THEY VEER TO MORE NW-N LATER TODAY.
TONIGHT...HIGH PRES BUILDING N OF THE WATERS. EXPECT N-NE WINDS AT
15 KT OR LESS WITH SEAS 4 FT OR LESS.
SUNDAY...NE FLOW SLOWLY INCREASES...WITH GUSTS UP TO 20 KT. EXPECT
HIGHEST WINDS E AND S OF NANTUCKET. FOR NOW...HAVE FORECASTED SEAS
AT 4 FT OR LESS...BUT MAY BUILD WITH THE NE FLOW ON THE OPEN OUTER
WATERS.
OUTLOOK /MONDAY THROUGH WEDNESDAY/...
PERSISTENT E GRADIENT WITH CONSIDERBLE FETCH WILL LIKELY KEEP SEAS
NEAR OR ABOVE 5 FT EXPOSED COASTAL WATERS MON NIGHT THRU WED MORNING AND
MAY BE STRONG ENOUGH TO MEET SCA WIND THRESHOLDS OVER MOST OF WATERS.
RESPITE LIKELY LATE WED THRU THU BEFORE RISK OF POTENT COASTAL LOW PRES
SYSTEM TOWARD END OF WEEK.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EST THIS MORNING FOR ANZ250-
254>256.
&&
$$
SYNOPSIS...EVT/THOMPSON
NEAR TERM...EVT
SHORT TERM...EVT
LONG TERM...THOMPSON
AVIATION...EVT/THOMPSON
MARINE...EVT/RLG/THOMPSON
000
FXUS61 KOKX 210933
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
433 AM EST SAT NOV 21 2009
.SYNOPSIS...
HIGH PRESSURE SLOWLY BUILDS INTO THE NORTHEASTERN UNITED STATES
THROUGH SUNDAY...THEN SLOWLY RETREATS INTO THE CANADIAN MARITIME
PROVINCES THROUGH EARLY NEXT WEEK. MEANWHILE...AN AREA OF LOW
PRESSURE WILL MOVE UP THE SOUTHEAST COAST MONDAY...THEN CONTINUE
NORTHEAST TO A POSITION EAST OF CAPE COD BY WEDNESDAY MORNING.
WEAK HIGH PRESSURE BUILDS IN FROM THE NORTH WEDNESDAY. ANOTHER
STORM SYSTEM WILL THEN IMPACT THE TRI-STATE TO CLOSE THE UPCOMING
WORK WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
A 700 HPA AND 500 HPA TROUGH MOVING ACROSS THE TRI-STATE WILL
PRODUCE SOME SCATTERED TO OCCASIONALLY BROKEN MID TO HIGH CLOUDS
ACROSS THE REGION TODAY. SUBSIDENCE FROM THE SURFACE HIGH
BUILDING IN WILL LIMIT MIXING TO AROUND 925 HPA...THIS COUPLED
WITH THE AFOREMENTIONED CLOUD COVER WILL PRODUCE HIGHS MAINLY IN
THE MID TO UPPER 50S (ABOUT 5 DEGREES ABOVE NORMAL AND CONSISTENT
WITH A MAV/MET BLEND).
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
RIDGING BUILDING IN FROM 700 HPA TO THE SURFACE SHOULD CREATE
ENOUGH SUBSIDENCE FOR MAINLY CLEAR SKY CONDITIONS TONIGHT...AND
ALLOW FOR DECOUPLING OF THE BOUNDARY LAYER TO PRODUCE LIGHT WINDS
AT THE SURFACE. AS A RESULT SHOULD HAVE DECENT R ADIATIONAL
COOLING TONIGHT...WITH LOWS IN THE 30S (AROUND 40-MID 40S NYC
METRO). THESE VALUES ARE NEAR NORMAL...EXCEPT 3-5 DEGREES ABOVE
NORMAL IN THE NYC METRO AND FOLLOWED COOLER MET GUIDANCE (MAV TOO
WARM GIVEN EXPECTED RADIATIONAL COOLING AND RELATIVELY SHALLOW
NATURE OF COLD AIR MOVING IN).
DEEP LAYER RIDGING BUILDS IN SUNDAY...LIMITING MIXING TO AROUND
950 HPA AND MINIMIZING ANY CLOUD COVER. SO EVEN WITH ABUNDANT
SUNSHINE...WILL ONLY HAVE HIGHS AROUND 50 - OR NEAR NORMAL FOR
THIS TIME OF YEAR).
RIDGE AXIS SLIDES OFFSHORE SUNDAY NIGHT...ALLOWING FOR ONSHORE
FLOW TO SET UP...BUT DAMMING SURFACE HIGH WILL CONTINUE LOW LEVEL
COLD ADVECTION...AS A RESULT WILL END UP SEEING LOWS A COUPLE OF
DEGREES COOLER THAN TONIGHT (ONCE AGAIN USED COOLER MET
GUIDANCE).
GFS AND ECMWF HAVE A FLATTER BASE TO THE SURFACE RIDGE THAN DO
THE NAM/CMC GGEM MONDAY-MONDAY NIGHT. THIS DIFFERENCE ALLOWS FOR
LOW LEVEL MOISTURE TO GET FURTHER INLAND IN THE GFS/ECMWF THAN IN
THE NAM/GGEM. THE SREF SUPPORTS THE STRUCTURE OF THE GFS/ECMWF SO
HAVE OPTED FOR A GFS/ECMWF BLEND FOR THE REMAINDER OF THE SHORT
TERM.
WITH OVER RUNNING SETTING UP ACROSS THE ENTIRE TRI-STATE MONDAY
AFTERNOON BRING CHANCE POPS TO ALL AREAS BY LATE AFTERNOON AND
CONTINUE MONDAY NIGHT. BETTER CHANCE OF RAIN MONDAY NIGHT WITH
500 AND 700 HPA SHORTWAVES CROSSING THE AREA AS WELL. FOR
TEMPERATURES USED MET/MAV BLEND MONDAY AND MEX/MEX ENSEMBLE MEAN
BLEND MONDAY NIGHT...WITH HIGHS NEAR NORMAL ON MONDAY AND 4-8
DEGREES ABOVE NORMAL MONDAY NIGHT (CLOUD COVER/RAIN LIMITING
DIURNAL RANGE).
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
LOW CONFIDENCE FORECAST IN THE EXTENDED WITH ALL THE MODELS
SHOWING SOMETHING DIFFERENT. GGEM IS MOST PROGRESSIVE WITH
COASTAL LOW FOR TUESDAY...GEFS SLOWEST AND MOST SURPRESSED TO THE
SOUTH (LIKE YESTERDAY/S 12Z ECMWF) AND GFS AND ECMWF IN BETWEEN
(WITH ECMWF MORE PROGRESSIVE THAN THE GFS).
FOR THE NEXT SYSTEM MOVING THROUGH THE GREAT LAKES INTO THE
NORTHEAST DURING THE MIDDLE TO LATE PART OF NEXT WEEK. THE GFS
MAINTAINS TWO DISTINCT CUTOFF LOWS (ACTUALLY LINKING THE FIRST
ONE WHICH IT HAS PASSING TO OUR NW WEDNESDAY WITH THE DEPARTING
STORM SYSTEM EARLY THIS WEEK)...WHILE THE ECMWF ABSORBS THE
SECOND CHUNK OF UPPER LEVEL ENERGY INTO THE FIRST CUTOFF LOW WITH
THIS LOW SLOWLY CROSSING THE NE LATE NEXT WEEK. THE GGEM
MAINTAINS TWO DISTINCT CIRCULATIONS WITHOUT ANY PHASING...BUT
DOES SUGGEST BY LOOKING AT THE INDIVIDUAL SYSTEMS THAT THE ECMWF
SOLUTION IS PLAUSIBLE. FOR NOW HAVE OPTED FOR A GFS/ECMWF BLEND
IN THE EXTENDED...BUT AS NOTED IN THE FIRST SENTENCE OF THE FIRST
PARAGRAPH...THIS IS A LOW CONFIDENCE FORECAST...SO EXPECT
CHANGES.
APPEARS FOR NOW THAT RAIN WILL LINGER INTO TUESDAY...THEN TAPER
OFF TUESDAY EVENING AS COASTAL LOW DEPARTS (CHANCE POPS TUESDAY
AND SLIGHT CHANCE POPS TUESDAY NIGHT). WHILE THERE IS SOME
SUGGESTION WEDNESDAY WILL END UP DRY WITH HIGH PRESSURE BUILDING
IN...IF GFS ENDS UP BEING RIGHT....COULD SEE SOME LIGHT SHOWERS
WEDNESDAY...SO SLIGHT CHANCE POPS. ON THE FLIP SIDE...GFS WOULD
HAVE THINGS DRY WEDNESDAY NIGHT/THURSDAY...BUT ECMWF BRINGS IN
PRECIPITATION AHEAD OF CONSOLIDATED CUTOFF...SO HAVE SLIGHT
CHANCE POPS BOTH PERIODS. BOTH MODELS SUGGEST RAIN FROM CUTOFF
LOW THURSDAY NIGHT/FRIDAY (POSSIBLY MIXED WITH/CHANGING TO SNOW
N/W OF NYC DEPENDING ON EXACT TRACK OF CUTOFF LOW AND HOW MUCH
LOW LEVEL COLD AIR ACTUALLY ENDS UP MOVING IN WITH IT)...SO
CHANCE POPS.
FOR TEMPERATURES USED A MEX/MEX ENSEMBLE MEAN BLEND WITH THE HIGH
MEMBER OF THE MEX ENSEMBLE MEAN BLENDED IN WEDNESDAY NIGHT-
THURSDAY NIGHT TO REFLECT WARMER ECMWF SOLUTION AT THOSE TIMES.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
VFR THROUGH THE DAY TODAY AS HIGH PRESSURE BUILDS TOWARD THE
AREA. WEST WINDS INTO THE EARLY MORNING HOURS WILL VEER TO THE
WEST/NW AT 5 TO 10 KTS FROM MID MORNING THROUGH THE AFTERNOON.
THESE WINDS VEER FURTHER TO THE NORTH TOWARD EVENING AND CONTINUE
OVERNIGHT.
OUTLOOK 06Z SUNDAY THROUGH WEDNESDAY...
SUN-MON MORNING: VFR.
MON AFTERNOON-TUE: SUB-VFR LIKELY.
TUE NIGHT: BECOMING VFR.
WED...MOST LIKELY VFR.
&&
.MARINE...
HIGH PRESSURE BUILDING INTO THE AREA WATERS TODAY RESULTS IN WEST
TO NORTHWEST WINDS. WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS. THE HIGH BUILDS INTO SOUTHEASTERN CANADA AND
NORTHERN NEW ENGLAND TONIGHT AND SUNDAY AND STRENGTHENS. WINDS
SHIFT TO THE NORTH THE TO THE NORTHEAST. SUNDAY NIGHT AND MONDAY
THE HIGH CONTINUES TO STRENGTHEN...THERE IS ALSO THE POTENTIAL
FOR A COASTAL LOW TO MOVE INTO THE HIGH. THIS WILL INCREASE THE
WINDS...GUSTS...AND SEAS ACROSS THE AREA WITH SMALL CRAFT
CONDITIONS BECOMING LIKELY BY SUNDAY NIGHT. WINDS COULD DROP
BELOW SMALL CRAFT LEVELS TUESDAY AS THE FORECAST WATERS ARE
BETWEEN TWO LOW PRESSURE SYSTEMS. ANOTHER LOW MAY APPROACH FROM
THE WEST DURING TUESDAY AND INTO WEDNESDAY. THERE IS SOME
UNCERTAINTY TO THE TRACK AND TIMING OF THE LOW AT THIS TIME. SEAS
ON THE OCEAN WILL LIKELY REMAIN AT SMALL CRAFT LEVELS INTO
WEDNESDAY.
&&
.HYDROLOGY...
DRY THROUGH MONDAY MORNING. A QUARTER TO A HALF AN INCH OF
RAINFALL IS POSSIBLE MONDAY AFTERNOON THROUGH TUESDAY WITH
LOCALLY HIGHER AMOUNTS WITHIN THE REASONABLE REALM OF
POSSIBILITIES. MORE PRECIPITATION IS EXPECTED TOWARDS THE END OF
NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
PUBLIC/HYDROLOGY...MALOIT
AVIATION...MET
MARINE...MET
000
FXUS61 KALY 210908
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
408 AM EST SAT NOV 21 2009
.SYNOPSIS...
A LARGE RIDGE OF HIGH PRESSURE WILL BUILD INTO NEW YORK
AND NEW ENGLAND THROUGH SUNDAY AND THEN LIFT NORTHEAST INTO THE
CANADIAN MARITIMES ON MONDAY. A LOW PRESSURE SYSTEM WILL THEN START
TO LIFT NORTHEAST FROM THE CAROLINA COAST MONDAY MORNING...AND PASS
SOUTHEAST OF LONG ISLAND TUESDAY MORNING...BRINGING UNSETTLED
WEATHER TO MUCH OF OUR REGION STARTING LATE MONDAY OR MONDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CLOUDS WILL SLOWLY SHRINK ACROSS FA THIS MORNING AS STRATO CU
ASSOCIATED WITH UPPER LEVEL TROUGH SLIDE THROUGH FA. LAKE RESPONSE
HAS BEEN WEAK AT BEST AND WITH AIRMASS NOT BEING VERY COLD EXPECT
THAT LAKE INDUCED CLOUDS WILL ONLY LINGER ACROSS PORTIONS OF
WESTERN ADIRONDACKS AND MOHAWK VALLEY INTO EARLY THIS AFTERNOON
AND THEN START TO DISSIPATE. WILL KEEP FORECAST DRY TODAY AND HAVE
TEMPS IN MOST AREAS A FEW DEGREES BELOW YESTERDAY WITH HIGHS
GENERALLY IN THE MID 40S TO MID 50S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
RIDGE OF HIGH PRESSURE WILL BE CENTERED OVER FA LATE TONIGHT INTO
EARLY SUNDAY AND THEN START TO LIFT NORTHEAST INTO CANADA. THIS
WILL RESULT IN MAINLY CLEAR SKIES WITH SEASONABLE TEMPS TONIGHT
WITH LOWS IN THE MID 20S TO MID 30S.
ON SUNDAY EXPECT THAT TEMPS MAYBE A FEW DEGREES COOLER IN THE
VALLEYS THAN TODAY AS DESPITE NEARLY FULL SUN...ORIENTATION OF
HIGH WILL RESULT IN A WEAK LOW LEVEL EASTERLY FLOW AND MIXING WILL
BE POOR ONLY UP TO 925 MB. HIGHS ON SUNDAY IN THE UPPER 40S TO
LOWER 50S.
ON SUNDAY NIGHT EXPECT MAINLY CLEAR SKIES IN THE EVENING AND THEN
PARTLY CLOUDY CONDITIONS LATE AS HIGH CLOUDS START TO LIFT
NORTHWARD AHEAD OF NEXT SYSTEM. LOWS SHOULD BE SIMILAR TO SATURDAY
NIGHT IN THE MID 20S TO LOWER 30S.
MONDAY LOOKS TO BE THE TRANSITION DAY WITH UNCERTAINTY STILL ON
EXACT TRACK AND ORIENTATION OF PCPN SHIELD...GEM APPEARS TO BE
THE FASTEST AND WETTEST WITH NAM NOT FAR BEHIND AS BOTH HAVE
LEADING EDGE OF PCPN SHIELD AT LEAST NORTH OF I90 BEFORE 00Z TUE AND
QPF AMOUNTS OF A TENTH TO A QUARTER OF AN INCH ACROSS FA. WHILE GFS
AND ECMWF SIGNIFICANTLY SLOWER WITH ONLY LIGHT RAIN AND A FEW
HUNDREDTHS OF AN INCH OF QPF INTO SE THIRD OF FA BEFORE 00Z TUE.
FOR NOW WILL KEEP FORECAST DRY WITH INCREASING CLOUDS ON MONDAY
MORNING AND THEN HAVE SLIGHT CHANCE TO CHANCE POPS SOUTH OF I90
MONDAY AFTERNOON. HIGH TEMPS ON MONDAY EXPECTED TO BE IN THE MID
TO UPPER 40S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MON NT-TUE...STILL QUITE A BIT OF UNCERTAINTY REGARDING NEXT
SYSTEM...CURRENTLY DEVELOPING ALONG THE WESTERN GULF COAST. THE
GENERAL TREND IN THE MODELS OVER THE LAST 24 HOURS HAS BEEN
WEAKER...AND FURTHER S/E WITH THE TRACK. THE 00Z/21 GEM IS MOST
AGGRESSIVE WITH THIS FEATURE...TRACKING IT OFF THE NEW ENGLAND
COAST...BUT STILL FAR ENOUGH WEST TO BRING AT LEAST SOME LIGHT RAIN
TO THE S/E HALF OF REGION. THE 00Z/21 GFS IS A BIT FURTHER
S/E...WHILE THE 00Z/21 ECMWF AND AT LEAST HALF OF THE MREFS KEEP
MOST PRECIP OUT OF OUR REGION...JUST CLIPPING FAR SE AREAS LATE MON
NT INTO EARLY TUE. BASED ON THIS LINGERING UNCERTAINTY...HAVE
INDICATED ONLY SLIGHT CHC TO LOW CHC POPS FOR RAIN ACROSS SOUTHERN
HALF OF REGION...WHILE KEEPING NORTHERN AREAS DRY. AS FOR
TEMPS...GENERALLY FOLLOWED CLOSE TO GMOS...WITH MINS MAINLY IN THE
30S...AND TUE MAXES MAINLY IN THE UPPER 40S TO LOWER 50S. SHOULD THE
CLOUDS/PRECIP EXTEND FURTHER N/W...EVEN COOLER MAXES ARE POSSIBLE.
TUE NT-WED...WILL INDICATE DRY CONDITIONS DURING THIS PERIOD...AS
MOST MODELS HINT AT SHORTWAVE RIDGING BUILDING INTO THE REGION.
HOWEVER...BY LATE WED...ENERGY AND WARM ADVECTION APPROACHING FROM
THE W MAY LEAD TO SOME RAIN BY LATE WED. THUS...HAVE INDICATED SOME
SLIGHT CHC TO LOW CHC POPS ACROSS SW AREAS FOR LATE WED.
OTHERWISE...EXPECT MAX TEMPS TO RANGE FROM THE MID 40S ACROSS FAR
NORTHERN AREAS...TO THE LOWER/MID 50S ACROSS CENTRAL AND SOUTHERN
AREAS...WITH OVERNIGHT MINS TUE NT MAINLY IN THE MID/UPPER 30S.
WED NT-FRI...MODELS HINT AT ADDITIONAL PRECIP DURING THIS
PERIOD...ALTHOUGH DIFFER ON THE EXACT TRIGGERING MECHANISMS. THE
00Z/GFS HINTS AT A FASTER WAVE MOVING THROUGH LATE WED INTO WED NT
WITH RAIN...WHILE MOST MREF MEMBERS...AND THE ECMWF DEPICT A
SLIGHTLY SLOWER UPPER LEVEL SYSTEM DEVELOPING ACROSS THE GREAT
LAKES...WHILE ANOTHER SFC LOW DEVELOPS ALONG THE SE COAST AND TRACKS
NNE. AT THE VERY LEAST...WILL INDICATE CHC POPS DURING THIS PERIOD
FOR RAIN...ALTHOUGH SOME WET SNOW COULD BE MIXED IN ACROSS HIGHER
ELEVATIONS EARLY THU. THEN...AS MID/UPPER LEVEL CONTINUE TO
COOL...WE EXPECT ANY RAIN TO GRADUALLY MIX WITH/CHANGE TO SNOW
ACROSS HIGHER ELEVATIONS BY LATE THU...AND PERHAPS WITHIN VALLEYS BY
THU NT OR EARLY FRI. WHETHER THIS PRECIPITATION IS WIDESPREAD AND
STEADY...OR MORE SCATTERED AND SHOWERY IS STILL UNCERTAIN...BUT
THERE IS AT LEAST SOME POSSIBILITY FOR PORTIONS OF THE REGION TO
RECEIVE MEASURABLE SNOW SOMETIME DURING THIS PERIOD. FOR
TEMPS...EXPECT MINS WED NT TO MAINLY BE IN THE 30S...WITH THU MAXES
MAINLY IN THE 30S FOR HIGHER ELEVATIONS...AND 40S FOR VALLEYS. FOR
THU NT...EXPECT MINS TO FALL INTO THE 20S FOR HIGHER
ELEVATIONS...AND LOWER/MID 30S FOR THE VALLEYS...WITH FRI MAXES
RANGING FROM THE LOWER/MID 30S ACROSS HIGHER ELEVATIONS...TO THE
UPPER 30S/LOWER 40S WITHIN THE VALLEYS. IT MAY ALSO BECOME QUITE
WINDY BY FRI...DEPENDING ON THE EVOLUTION AND TRACK OF ANY SFC LOW
PASSING TO OUR E OR NE.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE REGION SATURDAY THROUGH
SUNDAY.
VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES THROUGH AT LEAST
SATURDAY EVENING...ALTHOUGH A BRIEF PERIOD OF MVFR CIGS IS
POSSIBLE AT KGFL THROUGH ABOUT 14Z/SAT. HOWEVER...DUE TO LOW
PROBABILITY...HAVE NOT INDICATED THIS IN 06Z/SAT TAF ISSUANCE.
SOME PATCHY GROUND FOG COULD DEVELOP PRIOR TO 06Z/SUN AT KGFL DUE TO
GROUND FOG FORMATION...WITH A BETTER CHANCE EXPECTED THEREAFTER.
WINDS WILL REMAIN FROM THE W TO NW AT 5-10 KT TODAY...BECOMING
LIGHT/VARIABLE TONIGHT. SOME GUSTINESS IS POSSIBLE THROUGH SAT
MORNING...ESP AT KALB...POSSIBLY REACHING 15-20 KT. IN ADDITION...AT
KGFL...SOME VARIATIONS IN WIND DIRECTION IS POSSIBLE THIS AFTERNOON
DUE TO LOCALIZED TOPOGRAPHICAL EFFECTS.
OUTLOOK...
SUN...VFR...NO SIG WX.
MON-TUE...VFR-MVFR...CHC OF RAIN.
WED...VFR...CHC OF SHOWERS.
&&
.HYDROLOGY...
MOST RIVERS HAVE CRESTED AND ARE STARTING TO RECEDE OR WILL CREST
IN THE NEXT SEVERAL HOURS. RISES FROM THE RAIN THAT FELL THURSDAY
NIGHT INTO FRIDAY MORNING WERE GENERALLY 1 TO 2 FEET. AS HIGH
PRESSURE CONTINUES TO BUILD INTO THE REGION OVER THE
WEEKEND...WATER LEVELS WILL CONTINUE TO RECEDE IN MOST AREAS
THROUGH AT LEAST MONDAY. THE NEXT CHANCE FOR RAIN WILL BE LATE
MONDAY INTO TUESDAY MORNING...BUT ALLOT OF UNCERTAINTY EXISTS AT
THIS TIME WITH STORM TRACK AND QPF AMOUNTS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...11
NEAR TERM...11
SHORT TERM...11
LONG TERM...KL
AVIATION...KL
HYDROLOGY...11
000
FXUS61 KBOX 210850
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
350 AM EST SAT NOV 21 2009
.SYNOPSIS...
DRY AND PLEASANT WEATHER WILL CONTINUE THROUGH THIS WEEKEND WITH
HIGH PRESSURE IN PLACE. COASTAL LOW PRESSURE MAY STAY FAR ENOUGH TO
THE SOUTH TO JUST CLIP THE REGION MONDAY INTO TUESDAY. A FRONTAL
SYSTEM AND LOW PRESSURE MAY AFFECT SOUTHERN NEW ENGLAND TOWARD THE
END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ONLY A FEW PATCHES OF HIGH CLOUDS REMAIN OVER THE REGION AT 08Z...
FOR NOW. NOTING ANOTHER AREA OF MID-HIGH CLOUDS ACROSS NY/PA/NJ ON
THE IR SATELLITE LOOP...HEADING E IN THE WESTERLY UPPER FLOW.
WITH HIGH PRES BUILDING ACROSS NY INTO WESTERN NEW ENGLAND DURING
THE DAY...THE MID-HIGH CLOUDS WILL BE THE ONLY FLY IN THE OINTMENT
TODAY...WHICH WILL FILTER THE SUN SOMEWHAT. LIGHT WEST WINDS WILL
GRADUALLY SHIFT TO NORTH DURING THE DAY...BUT NOT MUCH OF A FACTOR.
WITH THE PLEASANT WEATHER AND NOT MUCH IN THE WAY OF COLD AIR
ADVECTION...EXPECT TEMPS TO REBOUND TO THE 50S ONCE AGAIN
TODAY...UPWARDS TO 10 DEGREES ABOVE NORMAL FOR LATE NOVEMBER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
TONIGHT...FEEL THAT THE MID-HIGH CLOUDS WILL SHIFT NE AS THE CENTER
OF THE HIGH BUILDS INTO NORTHERN NEW ENGLAND. WITH THE RIDGE AXIS N
OF THE REGION...WILL SEE LIGHT WINDS WITH SOME NE COMPONENT ALONG
THE COAST. MAY SEE A FEW CLOUDS LINGERING...ALONG WITH SOME PATCHY
VALLEY FOG DEVELOPING LATE AT NIGHT. OVERNIGHT LOWS WILL BOTTOM OUT
IN THE 30S TO NEAR 40...WHICH IS STILL AROUND 5 DEGREES ABOVE
NORMAL.
SUNDAY...HIGH PRESSURE REMAINS ACROSS NORTHERN NEW ENGLAND...MEANING
ANOTHER MOSTLY SUNNY DAY. MAY SEE SOME CLOUDS DEVELOP ACROSS SE
MA/RI WITH THE NE FLOW. MODELS ARE HINTING AT AN INCREASE IN PRES
GRADIENT ACROSS SOUTHERN AREAS AND ESPECIALLY OVER THE COASTAL
WATERS. THIS MAY HELP BRING LOW LEVEL MOISTURE ONSHORE WITH SOME
CLOUD DEVELOPMENT. WITH THE COOLER ONSHORE FLOW IN PLACE...EXPECT
DAYTIME HIGHS TO RUN COOLER THAN TODAY BUT STILL SEVERAL DEGREES
ABOVE NORMAL...WITH THE COOLEST READINGS ALONG THE COAST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGH PRESSURE WILL GRADUALLY SHIFT TO THE NE SUN INTO SUN
NIGHT...BUT SFC RIDGING WILL REMAIN IN CONTROL ACROSS SNE. THIS
WILL KEEP ANY MOISTURE TO THE SOUTH THROUGH SUN NIGHT...SO DRY
FORECAST.
MOSUNNY SKIES EXPECTED SUNDAY ACROSS MUCH OF THE REGION...BUT
SHALLOW LOW LEVEL MOISTURE IN DEVELOPING NE FLOW MAY BRING MORE
CLOUDINESS NEAR THE COAST. USED A MAV/MET BLEND FOR TEMPS.
NOT MUCH CHANGE IN CLOUD COVER EXPECTED SUN NIGHT WITH MOST CLOUDS
NEAR THE COAST. WE LEANED TOWARD COOLER MET GUIDANCE FOR TEMPS AS
GFS IS TOO FAST BRINGING IN MOISTURE.
MODELS STILL SHOW CONSIDERABLE SPREAD IN THEIR HANDLING OF COASTAL
LOW PRESSURE SYSTEM MON AND TUE SO FORECAST CONFIDENCE REMAINS BELOW
NORMAL. GFS/GGEM ARE FURTHEST NW AND BRING RAIN TO SNE MON/MON
NIGHT. GGEM REALLY HITS THE QPF HARD MON NIGHT. NAM/EC/UK ALL KEEP
RAIN TO THE SOUTH WITH COASTAL LOW REMAINING WELL OFFSHORE.
MAJORITY OF GEFS ENSEMBLES ALSO SOUTH WITH COASTAL LOW AND SUPPORT
DRIER SOLUTION SO WE WILL TREND IN THIS DIRECTION AND SCALE BACK THE
POPS WITH BEST CHC OF RAIN/SHOWERS NEAR THE COAST MON/MON NIGHT.
TUE...HELD ON TO CHC POPS SE COAST BASED ON EC SOLUTION WHICH
CONTINUED MOIST NE FLOW WITH OFFSHORE COASTAL LOW.
FORECAST CONFIDENCE REMAINS LOW FOR THE MIDDLE AND END OF THE WEEK
GIVEN THE CONSIDERABLE MODEL SPREAD IN HANDLING THE TIMING/EVOLUTION
OF SHORTWAVE ENERGY EJECTING FROM THE MIDWEST. WE GENERALLY
FOLLOWED ECMWF SOLUTION WHICH SHOWS AMPLIFYING MID LEVEL TROF
APPROACHING THE NE BY THE END OF THE WEEK...SO CHC SHOWERS THU INTO
FRI. BOTH GFS/ECMWF INDICATE THIS WILL BE A DYNAMIC SYSTEM BUT
DIFFER ON TIMING AND THE EXTENT OF PHASING. POTENTIAL IS THERE FOR
HEAVY PRECIP.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
TODAY...VFR.
TONIGHT...VFR. PATCHY FOG WITH BRIEF MVFR CIGS/VSBYS LATE AT NIGHT
IN THE NORMALLY SUSCEPTIBLE VALLEYS.
SUNDAY...VFR. MAY SEE PATCHY VFR TO LOCAL MVFR CIGS ALONG THE COAST
DURING THE LATE MORNING/AFTERNOON.
OUTLOOK /SUNDAY NIGHT THROUGH WEDNESDAY/...
SUN NIGHT...VFR...WITH LOW PROB OF MVFR CIGS DEVELOPING NEAR THE
COAST.
MON...MVFR POSSIBLE NEAR THE COAST WITH CHC RAIN. VFR NORTH OF THE
PIKE.
TUE...MVFR CIGS POSSIBLE...ESPECIALLY NEAR THE COAST.
WED...VFR.
&&
.MARINE...
TODAY...CONTINUED SMALL CRAFT MAINLY FOR SEAS ACROSS THE OUTER
WATERS. OFFSHORE BUOYS STILL REPORTING SWELLS AT 5-6 FT. ONLY KEPT
IT GOING FOR THE MORNING FOR NOW. WINDS WILL CONTINUE TO DIMINISH AS
THEY VEER TO MORE NW-N LATER TODAY.
TONIGHT...HIGH PRES BUILDING N OF THE WATERS. EXPECT N-NE WINDS AT
15 KT OR LESS WITH SEAS 4 FT OR LESS.
SUNDAY...NE FLOW SLOWLY INCREASES...WITH GUSTS UP TO 20 KT. EXPECT
HIGHEST WINDS E AND S OF NANTUCKET. FOR NOW...HAVE FORECASTED SEAS
AT 4 FT OR LESS...BUT MAY BUILD WITH THE NE FLOW ON THE OPEN OUTER
WATERS.
OUTLOOK /SUNDAY THROUGH WEDNESDAY/...
SUN NIGHT...DEVELOPING NE FLOW SLOWLY INCREASES BUT CONDITIONS
EXPECTED TO REMAIN BELOW SCA.
MON-TUE...A PERIOD OF SCA E/NE WINDS LIKELY...ESPECIALLY ACROSS
SOUTH COASTAL WATERS AS COASTAL LOW PASSES OFFSHORE. LOWERED
WNAWAVE GUIDANCE DUE TO ITS RELIANCE ON THE GFS...BUT STILL HAVE
SEAS BUILDING TO 5-7 FT.
WED...DIMINISHING WINDS AND SEAS WED AS GRADIENT RELAXES.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EST THIS MORNING FOR
ANZ250-254>256.
&&
$$
SYNOPSIS...KJC/EVT
NEAR TERM...EVT
SHORT TERM...EVT
LONG TERM...KJC
AVIATION...KJC/EVT
MARINE...KJC/EVT/RLG
000
FXUS61 KOKX 210536
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1236 AM EST SAT NOV 21 2009
.SYNOPSIS...
HIGH PRESSURE WILL BUILD EASTWARD FROM THE OHIO VALLEY. THIS HIGH
WILL RESULT IN FAIR AND DRY WEATHER THROUGH SUNDAY. THE
STRENGTHENING HIGH WILL THEN BUILD INTO NORTHERN NEW ENGLAND AND
THE CANADIAN MARITIMES SUNDAY NIGHT INTO MONDAY NIGHT...WHICH MAY
ALLOW WEAK LOW PRESSURE TO SLOWLY MOVE UP THE COAST MONDAY THROUGH
TUESDAY. FAIR WEATHER SHOULD RETURN ON TUESDAY. ANOTHER COASTAL
LOW MAY APPROACH THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
SECONDARY COLD FRONT WELL TO THE EAST ATTM. NW-W WINDS HAVE
DIMINISHED...BUT REMAIN IN THE 5 TO 10 KTS RANGE. THESE WINDS
SUFFICIENT TO PRECLUDE IDEAL RAD COOLING CONDITIONS. SO...IN SPITE
OF MOSTLY CLEAR SKIES...MIN TEMPS TONIGHT WILL BE ON THE WARMER
SIDE OF THE GUIDANCE...RANGING FROM THE 40S IN COASTAL AND URBAN
SECTIONS...TO THE MID/UPPER 30S INLAND. IF WINDS DO FULLY DECOUPLE
LATE TONIGHT...SOME INTERIOR LOCATIONS AND THE LI PINE BARRENS
COULD DROP TO AROUND FREEZING.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY/...
HIGH PRESSURE BUILDING FROM THE OH VALLEY WILL BE IN CONTROL
THROUGH AT LEAST SUNDAY EVENING. DOWNSLOPE FLOW AND MIXING TO
ABOUT 950 MB /2 KFT/ SHOULD BOOST HIGH TEMPS A LITTLE ABOVE MOST
GUIDANCE...WITH LOWER 60S IN URBAN NORTHEAST NJ AND THE CT RIVER
VALLEY...AND MID/UPPER 50S ELSEWHERE. AS THE HIGH BUILDS MORE
SQUARELY OVER THE AREA SAT NIGHT...MINS WILL BE A LITTLE COOLER
AND MORE LIKELY TO BOTTOM OUT AROUND FREEZING INLAND AND IN THE
LONG ISLAND PINE BARRENS...BUT SHOULD REMAIN ABOVE FROST ADVISORY
CRITERIA IN NYC AND HUDSON COUNTY NJ...THE ONLY REMAINING AREAS IN
THE CWA WHERE THE GROWING SEASON HAS NOT YET OFFICIALLY ENDED.
LOSS OF DOWNSLOPE FLOW AND AND LOWER 850-1000 MB THICKNESSES
UNDERNEATH THE HIGH ARGUE FOR HIGH TEMPS A FEW DEGREES COOLER THAN
THOSE OF SAT BUT STILL A TOUCH ABOVE GUIDANCE...MAINLY LOWER AND
MID 50S.
FORECAST UNCERTAINTIES BEGIN TO CREEP IN DURING SUN NIGHT-MON
REGARDING THE APPROACH OF A WEAK COASTAL LOW. HIGH PRESSURE
PASSING TO THE NORTH OF THE AREA BECOMES VERTICALLY STACKED AND
STRENGTHENS SUN NIGHT-MON...WHICH MAY SUPPRESS THE LOW ENOUGH TO
MAINTAIN FAIR WX. NAM/ECMWF AN SOME GEFS MEMBERS SUPPORT THIS
IDEA...WHILE THE OPERATIONAL GFS AND CANADIAN GGEM REMAIN WET.
HAVE BACKED OFF EARLIER LIKELY POP...BUT WITH THE AXIS OF SURFACE
RIDGING NORTH OF THE AREA AND MAINTAINING A LOW LEVEL ONSHORE
FLOW...AND A MID LEVEL SHORTWAVE UNDERCUTTING THE HIGH...THINK
CHANCE POP IS STILL IN ORDER FOR MON...ESPECIALLY IN
THE AFTERNOON.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS LACK CONSISTENCY RIGHT FROM THE BEGINNING OF THE PERIOD ON
THE STRENGTH OF THE SOUTHERN STREAM CLOSED LOW SHEARING NE MON
NIGHT...AND DISPLACEMENT OF STACKED RIDGING. THIS IS RESULTING IN
DIFFERENCES IN THE NORTHWARD TRACK AND STRENGTH OF THE SURFACE
LOW. WITH THIS UNCERTAINTY HAVE HELD POP TO CHANCE FOR MON NIGHT.
FORECAST DETAILS CONTINUE SHAKY THEREAFTER...WITH UNCERTAINTY IN
PROGRESSION OF PACIFIC SHORTWAVE FEATURES INTO THE LOWER 48.
MODELS HINT AT A PERIOD OF RIDGING TUE INTO WED AS UPPER ENERGY
DIGS OVER THE CENTRAL STATES...WITH LATE A WEEK COASTAL SYSTEM
POSSIBLE AS UPPER ENERGY WORKS TOWARD THE COAST. HAVE CONTINUED
WITH CHANCE POP FOR THIS PERIOD WITH UNCERTAINTY.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
VFR THROUGH THE DAY TODAY AS HIGH PRESSURE BUILDS TOWARD THE AREA.
WEST WINDS INTO THE EARLY MORNING HOURS WILL VEER TO THE WEST/NW AT
5 TO 10 KTS FROM MID MORNING THROUGH THE AFTERNOON. THESE WINDS VEER
FURTHER TO THE NORTH TOWARD EVENING AND CONTINUE OVERNIGHT.
OUTLOOK 06Z SUNDAY THROUGH WEDNESDAY...
SUN: VFR.
MON: SUB-VFR.
TUE AND WED...VFR LIKELY.
&&
.MARINE...
WINDS HAVE DIMINISHED BELOW 25 KTS...AND SEAS CONTINUE TO SUBSIDE.
OVERALL...I EXPECT SEAS TO REMAIN BELOW 5 FT...ALTHOUGH THEY COULD
TOUCH 5 FEET FROM TIME TO TIME. AS SUCH...SCA HAS BEEN CANCELLED
FOR THE TWO EASTERN OCEAN ZONES.
QUIET CONDITIONS SHOULD THEN BE THE RULE WITH HIGH PRESSURE IN
CONTROL UNTIL LATE SUN NIGHT-MON NIGHT...WHEN INCREASING EASTERLY
FLOW BETWEEN STRONG HIGH PRESSURE TO THE NORTHEAST AND A COASTAL
LOW TO THE SOUTH COULD YIELD SCA CONDITIONS.
WINDS SHOULD DIMINISH ON TUE AS HIGH PRESSURE BUILDS BACK IN...
WITH SEAS SUBSIDING BELOW SCA THROUGH WED.
&&
.HYDROLOGY...
SPREAD IN MODEL QPF IS QUITE LARGE FOR POSSIBLE COASTAL SYSTEM
SUNDAY NIGHT-MON NIGHT...WITH SUPPRESSED SOLUTIONS VIRTUALLY DRY
AND STRONGER/WETTER SOLUTIONS BRINGING OVER AN INCH ESPECIALLY TO
NYC METRO. CURRENT FORECAST LEANS TOWARD THE DRIER SIDE OF THE
ENVELOPE...SO HYDROLOGIC/FLOODING ISSUES APPEAR UNLIKELY ATTM.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
000
FXUS61 KALY 210526
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
1219 AM EST SAT NOV 21 2009
.SYNOPSIS...
AN UPPER LEVEL WEATHER DISTURBANCE WILL MOVE UP THE SAINT LAWRENCE
VALLEY OVERNIGHT FROM NEAR MONTREAL TO LABRADOR. HIGH PRESSURE WILL
BUILD INTO NEW YORK AND NEW ENGLAND THROUGH MONDAY FROM THE
MIDWEST AND GREAT LAKES REGION. HIGH PRESSURE WILL REMAIN OVER
THE NORTHEAST THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
UPDATED DEW POINT...POPS AND SKY COVER GRIDS. INCREASED CLOUDS
SLIGHTLY THROUGH TOMORROW MORNING TO REPRESENT OVC SKIES ESP OVER
ADIRONDACKS AND NORTH COUNTRY. EVEN THOUGH SKY GRIDS
INCREASED...TEMPS AND MIN TEMP STILL ON TARGET. DECREASED POPS AS
RADAR SHOWS DECREASING DBZS ACROSS HERKIMER AND HAMILTON
COUNTIES...AND UPPER LOW CONTINUES TO MOVE NORTHEAST OUT OF THE
AREA..WITH WINDS SHOWING A SLIGHT AND GRADUAL DECREASE.
OTHERWISE...CURRENT FORECAST IN GOOD SHAPE.
PREVIOUS DISCUSSION FOLLOWS...
AN UPPER LEVEL LOW PASSING TO OUR NORTH THIS AFTERNOON. WILL BE UNDER
CYCLONIC FLOW TONIGHT ALONG WITH LAKE ENHANCEMENT. HAVE KEPT CHANCE
POPS NORTH AND WEST OF CAPITAL DISTRICT WITH SLIGHT CHANCE POPS
INTO THE CAPITAL DISTRICT FOR THIS EVENING. GUIDANCE IS IN FAIRLY
GOOD AGREEMENT WITH TEMPERATURES FOR TONIGHT...IN THE 30S. LOOKING
AT RAIN SHOWERS WITH SOME SNOW SHOWERS POSSIBLE ACROSS THE HIGHER
TERRAIN OF THE WESTERN ADIRONDACKS. WESTERLY FLOW WEAKENS TONIGHT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY/...
FOR THE WEEKEND WE HAVE GOOD MODEL AGREEMENT. A SERIES OF 500 HPA
SHORT WAVES PRODUCE A TROFF FM YUL TO ORD ACROSS THE GRTLKS
RGN...WHILE HIGH PRESSURE BUILDS AT THE SFC OVER THE MIDWEST AND
GRTLKS. MODELS SHOW AN AREA OF HI RH MAINLY WELL WEST OF FCA...BUT
ENOUGH TO RESULT IN PS CONDS SAT. THIS AREA DYNAMICS DRYS OVER
TIME AS THE CENTER OF THE SFC HIGH BUILDS OVER FCA...AND WEAK
500HPA TROF AXIS SLIDES SE OF RGN SAT NIGHT. SUNDAY WOULD BRING
M.S. CONDS AS 500 HPA RIDGE BUILDS OVR THE GRTLKS AND SFC HIGH IS
OVER RGN. WITH LT WINDS AND A GOOD BIT OF SUNSHINE...PARTICULARLY
SUNDAY...WEEKEND SHOULD BRING NR TO SLIGHTLY ABV NORMALS TEMPS
WITH MID 40S TO MID 50S.
SUNDAY NIGHT AND MONDAY THE MDLS DIVERGE SIGNIFICANTLY IN THE
DEVELOPMENT...TIMING AND TRACK OF A COASTAL LOW. HPC...NAM...AND
THE GFS ENSEMBLE MEANS KEEP THE SYSTEM WELL SUPPRESSED TO OUT
SOUTH RESULTING IN MOSTLY CLEAR NIGHT SUNDAY NIGHT...AND PS-MS
CONDS MUCH OF MONDAY. BGM PLANS ON SLOWING THE PCPN THREAT
CONSIDERABLY IN THIS PERIOD AND BTV WILL KEEP IT DRY AND FAIR AS
WE WILL WITH ONLY A SLIGHT CHC ACROSS THE SOUTHERN TIER. WITH CLEAR
SKIES STARTED WITH COLD MET TEMPS AND TOOK THEM A FEW DEGREES
LOWED SUNDAY NIGHT. WITH MORE SUN ON MON
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
OPERATIONAL GFS OUTLIER IN GUIDANCE WITH COASTAL LOW MONDAY
THROUGH TUESDAY. ECMWF KEEPS FA DRY THROUGH THURSDAY AS HIGH
PRESSURE STAYS IN PLACE. THURSDAY INTO FRIDAY...TROUGH APPROACHES
FROM THE WEST...WITH A POSITIVE TILT BY LATE FRIDAY. PRECIP
MOVING OUT OF THE FA LATE FRIDAY INTO SATURDAY.
MONDAY NIGHT INTO TUESDAY MORNING LOW TEMPS EXPECTED IN THE M/U30S
IN THE VALLEYS AND L30S IN THE HIGHER TERRAIN. WARMING TO THE
M50S IN THE VALLEYS AND M/U40S IN THE HIGHER TERRAIN DURING THE
DAY. TUESDAY NIGHT THROUGH WEDNESDAY NIGHT A DEGREE OR TWO WARMER
BEFORE THE PRECIP SLOWLY MOVES ITS WAY IN ON THURSDAY. THURSDAY
MAX TEMPS IN THE M40S IN THE VALLEYS AND U30S IN THE HIGHER
TERRAIN...WITH ANY PRECIP DURING THE DAY AS RAIN...WITH SPOTS OF
-RASN ABV 2500FT. COOLER TEMPERATURES THURSDAY NIGHT WILL LEAD TO
RAIN MIXING WITH SNOW AND ALL SNOW AT TIMES. THURSDAY NIGHT
EXPECTING RAIN/SNOW MIX IN THE VALLEYS AND SNOW AT ELEVATIONS
500FT AND ABV. WITH CONDITIONS DRYING LATE FRIDAY...TEMPERATURES
A BIT COOLER ON FRIDAY WITH MAX TEMPS IN THE L/M40S IN THE
VALLEYS AND M/U30S IN THE HIGHER TERRAIN.
&&
.AVIATION /05Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL BUILD EAST ACROSS THE REGION SATURDAY THROUGH
SUNDAY.
VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES THROUGH AT LEAST
SATURDAY EVENING...ALTHOUGH A BRIEF PERIOD OF MVFR CIGS IS
POSSIBLE AT KGFL THROUGH ABOUT 14Z/SAT. HOWEVER...DUE TO LOW
PROBABILITY...HAVE NOT INDICATED THIS IN 06Z/SAT TAF ISSUANCE.
SOME PATCHY GROUND FOG COULD DEVELOP PRIOR TO 06Z/SUN AT KGFL DUE TO
GROUND FOG FORMATION...WITH A BETTER CHANCE EXPECTED THEREAFTER.
WINDS WILL REMAIN FROM THE W TO NW AT 5-10 KT TODAY...BECOMING
LIGHT/VARIABLE TONIGHT. SOME GUSTINESS IS POSSIBLE THROUGH SAT
MORNING...ESP AT KALB...POSSIBLY REACHING 15-20 KT. IN ADDITION...AT
KGFL...SOME VARIATIONS IN WIND DIRECTION IS POSSIBLE THIS AFTERNOON
DUE TO LOCALIZED TOPOGRAPHICAL EFFECTS.
OUTLOOK...
SUN...VFR...NO SIG WX.
MON-TUE...VFR-MVFR...CHC OF RAIN.
WED...VFR...CHC OF SHOWERS.
&&
.HYDROLOGY...
WATER LEVELS EXPECTED TO CONTINUE TO RISE ANOTHER HALF OF A FOOT
OR LESS IN REACTION TO LAST NIGHT/S RAINFALL. AS HIGH PRESSURE
BUILDS IN...EXPECT DRY CONDITIONS THROUGH AT LEAST MONDAY. WATER
LEVELS WILL THEN REMAIN NEARLY STEADY OR RECEDE. OUR NEXT CHANCES
FOR WIDESPREAD RAINFALL WILL BE THURSDAY INTO FRIDAY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KGS/SNYDER
NEAR TERM...IAA/KGS
SHORT TERM...SNYDER
LONG TERM...KGS
AVIATION...KL/KGS/IAA
HYDROLOGY...KGS
000
FXUS61 KBOX 210430
AFDBOX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAUNTON MA
1130 PM EST FRI NOV 20 2009
.SYNOPSIS...
DRY AND PLEASANT WEATHER WILL RETURN OVER THE WEEKEND WITH HIGH
PRESSURE IN PLACE. COASTAL LOW PRESSURE MAY STAY FAR ENOUGH TO THE
SOUTH TO JUST CLIP THE REGION MONDAY INTO TUESDAY. A FRONTAL SYSTEM
AND LOW PRESSURE MAY AFFECT SOUTHERN NEW ENGLAND TOWARD THE END OF
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
IR SATELLITE SHOWING A THIN VEIL OF HIGH CIRRUS CLOUDS CROSSING THE
REGION IN THE UPPER LEVEL W FLOW AT 04Z. NOTING MORE CIRRUS CLOUDS
WORKING OUT OF PA/OHIO VALLEY THAT WILL WORK E OVERNIGHT. HIGH PRES
WILL WORK OUT OF WV/MD/VA REGION INTO NY STATE BY SAT MORNING.
WINDS HAVE DIMINISH ACROSS MANY LOWLAND AREAS...WITH SOME WIND STILL
ACROSS THE HIGHER TERRAIN. DEWPTS DOWN TO THE 30S TO AROUND 40 AS
TEMPS HAVE FALLEN TO THE 40S AT 04Z...EXCEPT AROUND 50 ON THE
ISLANDS.
HAVE KEPT MINS IN THE MID 30S TO MID 40S TOWARD SUNRISE...BUT WILL
DEPEND UPON IF HIGH CLOUDS BREAK UP ENOUGH TO ALLOW TEMPS TO DROP.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
HIGH PRESSURE CONTINUES TO BUILD INTO SOUTHERN NEW ENGLAND THROUGH
SATURDAY...MOVING OVER NORTHERN NEW ENGLAND SATURDAY NIGHT. CLEAR
SKIES...LIGHT WINDS...AND ABOVE NORMAL TEMPERATURES WILL BE THE RULE.
SATURDAY NIGHT...TEMPERATURES WILL DROP INTO THE 30S /RIGHT AROUND
NORMAL/. USED A BLEND OF AVAILABLE GUIDANCE FOR THE GRIDS.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGH PRESSURE WILL GRADUALLY SHIFT TO THE NE SUN INTO SUN
NIGHT...BUT SFC RIDGING WILL REMAIN IN CONTROL ACROSS SNE. THIS
WILL KEEP ANY MOISTURE TO THE SOUTH THROUGH SUN NIGHT...SO DRY
FORECAST.
MOSUNNY SKIES EXPECTED SUNDAY ACROSS MUCH OF THE REGION...BUT
SHALLOW LOW LEVEL MOISTURE IN DEVELOPING NE FLOW MAY BRING MORE
CLOUDINESS NEAR THE COAST. USED A MAV/MET BLEND FOR TEMPS.
NOT MUCH CHANGE IN CLOUD COVER EXPECTED SUN NIGHT WITH MOST CLOUDS
NEAR THE COAST. WE LEANED TOWARD COOLER MET GUIDANCE FOR TEMPS AS
GFS IS TOO FAST BRINGING IN MOISTURE.
MODELS STILL SHOW CONSIDERABLE SPREAD IN THEIR HANDLING OF COASTAL
LOW PRESSURE SYSTEM MON AND TUE SO FORECAST CONFIDENCE REMAINS BELOW
NORMAL. GFS/GGEM ARE FURTHEST NW AND BRING RAIN TO SNE MON/MON
NIGHT. GGEM REALLY HITS THE QPF HARD MON NIGHT. NAM/EC/UK ALL KEEP
RAIN TO THE SOUTH WITH COASTAL LOW REMAINING WELL OFFSHORE.
MAJORITY OF GEFS ENSEMBLES ALSO SOUTH WITH COASTAL LOW AND SUPPORT
DRIER SOLUTION SO WE WILL TREND IN THIS DIRECTION AND SCALE BACK THE
POPS WITH BEST CHC OF RAIN/SHOWERS NEAR THE COAST MON/MON NIGHT.
TUE...HELD ON TO CHC POPS SE COAST BASED ON EC SOLUTION WHICH
CONTINUED MOIST NE FLOW WITH OFFSHORE COASTAL LOW.
FORECAST CONFIDENCE REMAINS LOW FOR THE MIDDLE AND END OF THE WEEK
GIVEN THE CONSIDERABLE MODEL SPREAD IN HANDLING THE TIMING/EVOLUTION
OF SHORTWAVE ENERGY EJECTING FROM THE MIDWEST. WE GENERALLY
FOLLOWED ECMWF SOLUTION WHICH SHOWS AMPLIFYING MID LEVEL TROF
APPROACHING THE NE BY THE END OF THE WEEK...SO CHC SHOWERS THU INTO
FRI. BOTH GFS/ECMWF INDICATE THIS WILL BE A DYNAMIC SYSTEM BUT
DIFFER ON TIMING AND THE EXTENT OF PHASING. POTENTIAL IS THERE FOR
HEAVY PRECIP.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
OVERNIGHT...VFR.
SAT AND SAT NIGHT...
VFR WITH LIGHT W-NW WINDS.
OUTLOOK /SUNDAY THROUGH WEDNESDAY/...
SUN...VFR...WITH LOW PROB OF MVFR CIGS DEVELOPING NEAR THE COAST.
MON...MVFR POSSIBLE NEAR THE COAST WITH CHC RAIN. VFR NORTH OF THE
PIKE.
TUE...MVFR CIGS POSSIBLE...ESPECIALLY NEAR THE COAST.
WED...VFR.
&&
.MARINE...
OVERNIGHT...HAVE TAKEN DOWN THE SMALL CRAFT ON BOTH BLOCK ISLAND AND
RHODE ISLAND SOUNDS. NOTED SEAS HAVE SUBSIDED TO 3-4 FEET WELL
OFFSHORE. CONTINUE THE SMALL CRAFT THROUGH THE OVERNIGHT ACROSS THE
FAR OUTER WATERS AS SEAS REMAIN AT 5-6 FEET. SOME GUSTS UP TO 25 KT
WILL ALSO CONTINUE UNTIL AROUND 06Z-07Z ACROSS THE WATERS EAST OF
THE MASSACHUSETTS COAST.
SATURDAY...W-NW WINDS UP TO 20 KT. SEAS MAY LINGER AT AROUND 5 FEET
ON THE OUTER WATERS THROUGH MID TO LATE MORNING. WAVE GUIDANCE HAS
INITIALIZED HIGH SO AM NOT CONFIDENT THAT SEAS WON/T DROP A BIT
FASTER THAN FORECAST. SO HAVE OPTED TO NOT EXTEND THE SMALL CRAFT
YET.
SATURDAY NIGHT...HIGH PRESSURE BUILDS OVERHEAD WITH WINDS AND SEAS
DIMINISHING.
OUTLOOK /SUNDAY THROUGH WEDNESDAY/...
SUN-SUN NIGHT...DEVELOPING NE FLOW SLOWLY INCREASES THROUGH SUN
NIGHT BUT CONDITIONS EXPECTED TO REMAIN BELOW SCA.
MON-TUE...A PERIOD OF SCA E/NE WINDS LIKELY...ESPECIALLY ACROSS
SOUTH COASTAL WATERS AS COASTAL LOW PASSES OFFSHORE. LOWERED
WNAWAVE GUIDANCE DUE TO ITS RELIANCE ON THE GFS...BUT STILL HAVE
SEAS BUILDING TO 5-7 FT.
WED...DIMINISHING WINDS AND SEAS WED AS GRADIENT RELAXES.
&&
.EQUIPMENT...
THE FAA TERMINAL DOPPLER WEATHER RADAR /TDWR/ S OF BOSTON IS OUT OF
SERVICE UNTIL FURTHER NOTICE.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 AM EST SATURDAY FOR ANZ250-256.
SMALL CRAFT ADVISORY UNTIL 9 AM EST SATURDAY FOR ANZ254-255.
&&
$$
SYNOPSIS...KJC/RLG
NEAR TERM...EVT
SHORT TERM...RLG
LONG TERM...KJC
AVIATION...KJC/NOCERA/EVT
MARINE...KJC/EVT/RLG
EQUIPMENT...
000
FXUS61 KOKX 210337
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1037 PM EST FRI NOV 20 2009
.SYNOPSIS...
HIGH PRESSURE WILL BUILD EASTWARD FROM THE OHIO VALLEY. THIS HIGH
WILL RESULT IN FAIR AND DRY WEATHER THROUGH SUNDAY. THE
STRENGTHENING HIGH WILL THEN BUILD INTO NORTHERN NEW ENGLAND AND
THE CANADIAN MARITIMES SUNDAY NIGHT INTO MONDAY NIGHT...WHICH MAY
ALLOW WEAK LOW PRESSURE TO SLOWLY MOVE UP THE COAST MONDAY THROUGH
TUESDAY. FAIR WEATHER SHOULD RETURN ON TUESDAY. ANOTHER COASTAL
LOW MAY APPROACH THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
SECONDARY COLD FRONT WELL TO THE EAST ATTM. NW-W WINDS HAVE
DIMINISHED...BUT REMAIN IN THE 5 TO 10 KTS RANGE. THESE WINDS
SUFFICIENT TO PRECLUDE IDEAL RAD COOLING CONDITIONS. SO...IN SPITE
OF MOSTLY CLEAR SKIES...MIN TEMPS TONIGHT WILL BE ON THE WARMER
SIDE OF THE GUIDANCE...RANGING FROM THE 40S IN COASTAL AND URBAN
SECTIONS...TO THE MID/UPPER 30S INLAND. IF WINDS DO FULLY DECOUPLE
LATE TONIGHT...SOME INTERIOR LOCATIONS AND THE LI PINE BARRENS
COULD DROP TO AROUND FREEZING.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
HIGH PRESSURE BUILDING FROM THE OH VALLEY WILL BE IN CONTROL
THROUGH AT LEAST SUNDAY EVENING. DOWNSLOPE FLOW AND MIXING TO
ABOUT 950 MB /2 KFT/ SHOULD BOOST HIGH TEMPS A LITTLE ABOVE MOST
GUIDANCE...WITH LOWER 60S IN URBAN NORTHEAST NJ AND THE CT RIVER
VALLEY...AND MID/UPPER 50S ELSEWHERE. AS THE HIGH BUILDS MORE
SQUARELY OVER THE AREA SAT NIGHT...MINS WILL BE A LITTLE COOLER
AND MORE LIKELY TO BOTTOM OUT AROUND FREEZING INLAND AND IN THE
LONG ISLAND PINE BARRENS...BUT SHOULD REMAIN ABOVE FROST ADVISORY
CRITERIA IN NYC AND HUDSON COUNTY NJ...THE ONLY REMAINING AREAS IN
THE CWA WHERE THE GROWING SEASON HAS NOT YET OFFICIALLY ENDED.
LOSS OF DOWNSLOPE FLOW AND AND LOWER 850-1000 MB THICKNESSES
UNDERNEATH THE HIGH ARGUE FOR HIGH TEMPS A FEW DEGREES COOLER THAN
THOSE OF SAT BUT STILL A TOUCH ABOVE GUIDANCE...MAINLY LOWER AND
MID 50S.
FORECAST UNCERTAINTIES BEGIN TO CREEP IN DURING SUN NIGHT-MON
REGARDING THE APPROACH OF A WEAK COASTAL LOW. HIGH PRESSURE
PASSING TO THE NORTH OF THE AREA BECOMES VERTICALLY STACKED AND
STRENGTHENS SUN NIGHT-MON...WHICH MAY SUPPRESS THE LOW ENOUGH TO
MAINTAIN FAIR WX. NAM/ECMWF AN SOME GEFS MEMBERS SUPPORT THIS
IDEA...WHILE THE OPERATIONAL GFS AND CANADIAN GGEM REMAIN WET.
HAVE BACKED OFF EARLIER LIKELY POP...BUT WITH THE AXIS OF SURFACE
RIDGING NORTH OF THE AREA AND MAINTAINING A LOW LEVEL ONSHORE
FLOW...AND A MID LEVEL SHORTWAVE UNDERCUTTING THE HIGH...THINK
CHANCE POP IS STILL IN ORDER FOR MON...ESPECIALLY IN
THE AFTERNOON.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS LACK CONSISTENCY RIGHT FROM THE BEGINNING OF THE PERIOD ON
THE STRENGTH OF THE SOUTHERN STREAM CLOSED LOW SHEARING NE MON
NIGHT...AND DISPLACEMENT OF STACKED RIDGING. THIS IS RESULTING IN
DIFFERENCES IN THE NORTHWARD TRACK AND STRENGTH OF THE SURFACE
LOW. WITH THIS UNCERTAINTY HAVE HELD POP TO CHANCE FOR MON NIGHT.
FORECAST DETAILS CONTINUE SHAKY THEREAFTER...WITH UNCERTAINTY IN
PROGRESSION OF PACIFIC SHORTWAVE FEATURES INTO THE LOWER 48.
MODELS HINT AT A PERIOD OF RIDGING TUE INTO WED AS UPPER ENERGY
DIGS OVER THE CENTRAL STATES...WITH LATE A WEEK COASTAL SYSTEM
POSSIBLE AS UPPER ENERGY WORKS TOWARD THE COAST. HAVE CONTINUED
WITH CHANCE POP FOR THIS PERIOD WITH UNCERTAINTY.
&&
.AVIATION /04Z SATURDAY THROUGH WEDNESDAY/...
VFR AS HIGH PRESSURE BUILDS INTO THE REGION THROUGH SATURDAY.
WEST/NW WINDS WILL REMAIN AROUND 5 TO 10 KTS...AND THIS WILL CONTINUE
SATURDAY.
OUTLOOK 00Z SUNDAY THROUGH WEDNESDAY...
SAT: VFR.
SUN: VFR.
SUN NIGHT-MON: SUB-VFR.
TUE AND WED...VFR LIKELY.
&&
.MARINE...
WINDS HAVE DIMINISHED BELOW 25 KTS...AND SEAS CONTINUE TO SUBSIDE.
OVERALL...I EXPECT SEAS TO REMAIN BELOW 5 FT...ALTHOUGH THEY COULD
TOUCH 5 FEET FROM TIME TO TIME. AS SUCH...SCA HAS BEEN CANCELLED
FOR THE TWO EASTERN OCEAN ZONES.
QUIET CONDITIONS SHOULD THEN BE THE RULE WITH HIGH PRESSURE IN
CONTROL UNTIL LATE SUN NIGHT-MON NIGHT...WHEN INCREASING EASTERLY
FLOW BETWEEN STRONG HIGH PRESSURE TO THE NORTHEAST AND A COASTAL
LOW TO THE SOUTH COULD YIELD SCA CONDITIONS.
WINDS SHOULD DIMINISH ON TUE AS HIGH PRESSURE BUILDS BACK IN...
WITH SEAS SUBSIDING BELOW SCA THROUGH WED.
&&
.HYDROLOGY...
SPREAD IN MODEL QPF IS QUITE LARGE FOR POSSIBLE COASTAL SYSTEM
SUNDAY NIGHT-MON NIGHT...WITH SUPPRESSED SOLUTIONS VIRTUALLY DRY
AND STRONGER/WETTER SOLUTIONS BRINGING OVER AN INCH ESPECIALLY TO
NYC METRO. CURRENT FORECAST LEANS TOWARD THE DRIER SIDE OF THE
ENVELOPE...SO HYDROLOGIC/FLOODING ISSUES APPEAR UNLIKELY ATTM.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...BG
NEAR TERM...BG/PW
SHORT TERM...BG
LONG TERM...NV
AVIATION...PW
MARINE...BG/NV/PW
HYDROLOGY...BG/NV
000
FXUS61 KALY 210032
AFDALY
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ALBANY NY
732 PM EST FRI NOV 20 2009
.SYNOPSIS...
AN UPPER LEVEL WEATHER DISTURBANCE WILL MOVE UP THE SAINT LAWRENCE
VALLEY OVERNIGHT FROM NEAR MONTREAL TO LABRADOR. HIGH PRESSURE WILL
BUILD INTO NEW YORK AND NEW ENGLAND THROUGH MONDAY FROM THE
MIDWEST AND GREAT LAKES REGION. HIGH PRESSURE WILL REMAIN OVER
THE NORTHEAST THROUGH EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
UPDATED DEW POINT...POPS AND SKY COVER GRIDS. INCREASED CLOUDS
SLIGHTLY THROUGH TOMORROW MORNING TO REPRESENT OVC SKIES ESP OVER
ADIRONDACKS AND NORTH COUNTRY. EVEN THOUGH SKY GRIDS
INCREASED...TEMPS AND MIN TEMP STILL ON TARGET. DECREASED POPS AS
RADAR SHOWS DECREASING DBZS ACROSS HERKIMER AND HAMILTON
COUNTIES...AND UPPER LOW CONTINUES TO MOVE NORTHEAST OUT OF THE
AREA..WITH WINDS SHOWING A SLIGHT AND GRADUAL DECREASE.
OTHERWISE...CURRENT FORECAST IN GOOD SHAPE.
PREVIOUS DISCUSSION FOLLOWS...
AN UPPER LEVEL LOW PASSING TO OUR NORTH THIS AFTERNOON. WILL BE UNDER
CYCLONIC FLOW TONIGHT ALONG WITH LAKE ENHANCEMENT. HAVE KEPT CHANCE
POPS NORTH AND WEST OF CAPITAL DISTRICT WITH SLIGHT CHANCE POPS
INTO THE CAPITAL DISTRICT FOR THIS EVENING. GUIDANCE IS IN FAIRLY
GOOD AGREEMENT WITH TEMPERATURES FOR TONIGHT...IN THE 30S. LOOKING
AT RAIN SHOWERS WITH SOME SNOW SHOWERS POSSIBLE ACROSS THE HIGHER
TERRAIN OF THE WESTERN ADIRONDACKS. WESTERLY FLOW WEAKENS TONIGHT.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
FOR THE WEEKEND WE HAVE GOOD MODEL AGREEMENT. A SERIES OF 500 HPA
SHORT WAVES PRODUCE A TROFF FM YUL TO ORD ACROSS THE GRTLKS
RGN...WHILE HIGH PRESSURE BUILDS AT THE SFC OVER THE MIDWEST AND
GRTLKS. MODELS SHOW AN AREA OF HI RH MAINLY WELL WEST OF FCA...BUT
ENOUGH TO RESULT IN PS CONDS SAT. THIS AREA DYNAMICS DRYS OVER
TIME AS THE CENTER OF THE SFC HIGH BUILDS OVER FCA...AND WEAK
500HPA TROF AXIS SLIDES SE OF RGN SAT NIGHT. SUNDAY WOULD BRING
M.S. CONDS AS 500 HPA RIDGE BUILDS OVR THE GRTLKS AND SFC HIGH IS
OVER RGN. WITH LT WINDS AND A GOOD BIT OF SUNSHINE...PARTICULARLY
SUNDAY...WEEKEND SHOULD BRING NR TO SLIGHTLY ABV NORMALS TEMPS
WITH MID 40S TO MID 50S.
SUNDAY NIGHT AND MONDAY THE MDLS DIVERGE SIGNIFICANTLY IN THE
DEVELOPMENT...TIMING AND TRACK OF A COASTAL LOW. HPC...NAM...AND
THE GFS ENSEMBLE MEANS KEEP THE SYSTEM WELL SUPPRESSED TO OUT
SOUTH RESULTING IN MOSTLY CLEAR NIGHT SUNDAY NIGHT...AND PS-MS
CONDS MUCH OF MONDAY. BGM PLANS ON SLOWING THE PCPN THREAT
CONSIDERABLY IN THIS PERIOD AND BTV WILL KEEP IT DRY AND FAIR AS
WE WILL WITH ONLY A SLIGHT CHC ACROSS THE SOUTHERN TIER. WITH CLEAR
SKIES STARTED WITH COLD MET TEMPS AND TOOK THEM A FEW DEGREES
LOWED SUNDAY NIGHT. WITH MORE SUN ON MON
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
OPERATIONAL GFS OUTLIER IN GUIDANCE WITH COASTAL LOW MONDAY
THROUGH TUESDAY. ECMWF KEEPS FA DRY THROUGH THURSDAY AS HIGH
PRESSURE STAYS IN PLACE. THURSDAY INTO FRIDAY...TROUGH APPROACHES
FROM THE WEST...WITH A POSITIVE TILT BY LATE FRIDAY. PRECIP
MOVING OUT OF THE FA LATE FRIDAY INTO SATURDAY.
MONDAY NIGHT INTO TUESDAY MORNING LOW TEMPS EXPECTED IN THE M/U30S
IN THE VALLEYS AND L30S IN THE HIGHER TERRAIN. WARMING TO THE
M50S IN THE VALLEYS AND M/U40S IN THE HIGHER TERRAIN DURING THE
DAY. TUESDAY NIGHT THROUGH WEDNESDAY NIGHT A DEGREE OR TWO WARMER
BEFORE THE PRECIP SLOWLY MOVES ITS WAY IN ON THURSDAY. THURSDAY
MAX TEMPS IN THE M40S IN THE VALLEYS AND U30S IN THE HIGHER
TERRAIN...WITH ANY PRECIP DURING THE DAY AS RAIN...WITH SPOTS OF
-RASN ABV 2500FT. COOLER TEMPERATURES THURSDAY NIGHT WILL LEAD TO
RAIN MIXING WITH SNOW AND ALL SNOW AT TIMES. THURSDAY NIGHT
EXPECTING RAIN/SNOW MIX IN THE VALLEYS AND SNOW AT ELEVATIONS
500FT AND ABV. WITH CONDITIONS DRYING LATE FRIDAY...TEMPERATURES
A BIT COOLER ON FRIDAY WITH MAX TEMPS IN THE L/M40S IN THE
VALLEYS AND M/U30S IN THE HIGHER TERRAIN.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AN UPPER LEVEL LOW IS PASSING TO OUR NORTH THIS EVENING. REGION WILL
BE UNDER CYCLONIC FLOW TONIGHT WITH SURFACE HIGH PRESSURE BUILDING
IN FROM THE WEST ON SATURDAY.
VFR CONDITIONS EXPECTED TO CONTINUE THIS EVENING...WITH MVFR
CONDITIONS FOR CIGS POSSIBLE TONIGHT AT KALB-KGFL WHICH WE HAVE
INDICATED A BKN030...MAINLY AFTER MIDNIGHT. A WEAK MID LEVEL
DISTURBANCE UPSTREAM /OHIO RIVER VALLEY/ HAS RESULTED IN A
SCT-BKN020-040 WHICH WE WILL CONTINUE TO MONITOR TRENDS.
THEREAFTER...MODEL FORECAST SOUNDINGS ARE RATHER PRONOUNCED WITH
THIS CLOUD DECK BECOME DOMINATE OVERNIGHT AND WILL PLACE A MVFR CIG
AT THIS TIME. OTHERWISE...KPOU SHOULD REMAIN VFR WITH A SCT MID
LEVEL DECK EXPECTED OVERNIGHT.
WINDS WILL CONTINUE TO DECREASE IN SPEED OVERNIGHT AS SURFACE HIGH
BUILDS INTO THE REGION.
OUTLOOK...
SUN...VFR...NO SIG WX.
MON-TUE...VFR-MVFR...CHC OF RAIN.
WED...VFR...CHC OF SHOWERS.
&&
.HYDROLOGY...
WATER LEVELS EXPECTED TO CONTINUE TO RISE ANOTHER HALF OF A FOOT
OR LESS IN REACTION TO LAST NIGHT/S RAINFALL. AS HIGH PRESSURE
BUILDS IN...EXPECT DRY CONDITIONS THROUGH AT LEAST MONDAY. WATER
LEVELS WILL THEN REMAIN NEARLY STEADY OR RECEDE. OUR NEXT CHANCES
FOR WIDESPREAD RAINFALL WILL BE THURSDAY INTO FRIDAY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...KGS/SNYDER
NEAR TERM...IAA/KGS
SHORT TERM...SNYDER
LONG TERM...KGS
AVIATION...IAA
HYDROLOGY...KGS
000
FXUS61 KOKX 202349
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
649 PM EST FRI NOV 20 2009
.SYNOPSIS...
HIGH PRESSURE WILL BUILD EASTWARD FROM THE OHIO VALLEY. THIS HIGH
WILL RESULT IN FAIR AND DRY WEATHER THROUGH SUNDAY. THE
STRENGTHENING HIGH WILL THEN BUILD INTO NORTHERN NEW ENGLAND AND
THE CANADIAN MARITIMES SUNDAY NIGHT INTO MONDAY NIGHT...WHICH MAY
ALLOW WEAK LOW PRESSURE TO SLOWLY MOVE UP THE COAST MONDAY THROUGH
TUESDAY. FAIR WEATHER SHOULD RETURN ON TUESDAY. ANOTHER COASTAL
LOW MAY APPROACH THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
SECONDARY COLD FRONT WELL TO THE EAST ATTM. NW-W WINDS HAVE
DIMINISHED...BUT REMAIN IN THE 5 TO 10 KTS RANGE. THESE WINDS
SUFFICIENT TO PRECLUDE IDEAL RAD COOLING CONDITIONS. SO...IN SPITE
OF MOSTLY CLEAR SKIES...MIN TEMPS TONIGHT WILL BE ON THE WARMER
SIDE OF THE GUIDANCE...RANGING FROM THE 40S IN COASTAL AND URBAN
SECTIONS...TO THE MID/UPPER 30S INLAND. IF WINDS DO FULLY DECOUPLE
LATE TONIGHT...SOME INTERIOR LOCATIONS AND THE LI PINE BARRENS
COULD DROP TO AROUND FREEZING.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
HIGH PRESSURE BUILDING FROM THE OH VALLEY WILL BE IN CONTROL
THROUGH AT LEAST SUNDAY EVENING. DOWNSLOPE FLOW AND MIXING TO
ABOUT 950 MB /2 KFT/ SHOULD BOOST HIGH TEMPS A LITTLE ABOVE MOST
GUIDANCE...WITH LOWER 60S IN URBAN NORTHEAST NJ AND THE CT RIVER
VALLEY...AND MID/UPPER 50S ELSEWHERE. AS THE HIGH BUILDS MORE
SQUARELY OVER THE AREA SAT NIGHT...MINS WILL BE A LITTLE COOLER
AND MORE LIKELY TO BOTTOM OUT AROUND FREEZING INLAND AND IN THE
LONG ISLAND PINE BARRENS...BUT SHOULD REMAIN ABOVE FROST ADVISORY
CRITERIA IN NYC AND HUDSON COUNTY NJ...THE ONLY REMAINING AREAS IN
THE CWA WHERE THE GROWING SEASON HAS NOT YET OFFICIALLY ENDED.
LOSS OF DOWNSLOPE FLOW AND AND LOWER 850-1000 MB THICKNESSES
UNDERNEATH THE HIGH ARGUE FOR HIGH TEMPS A FEW DEGREES COOLER THAN
THOSE OF SAT BUT STILL A TOUCH ABOVE GUIDANCE...MAINLY LOWER AND
MID 50S.
FORECAST UNCERTAINTIES BEGIN TO CREEP IN DURING SUN NIGHT-MON
REGARDING THE APPROACH OF A WEAK COASTAL LOW. HIGH PRESSURE
PASSING TO THE NORTH OF THE AREA BECOMES VERTICALLY STACKED AND
STRENGTHENS SUN NIGHT-MON...WHICH MAY SUPPRESS THE LOW ENOUGH TO
MAINTAIN FAIR WX. NAM/ECMWF AN SOME GEFS MEMBERS SUPPORT THIS
IDEA...WHILE THE OPERATIONAL GFS AND CANADIAN GGEM REMAIN WET.
HAVE BACKED OFF EARLIER LIKELY POP...BUT WITH THE AXIS OF SURFACE
RIDGING NORTH OF THE AREA AND MAINTAINING A LOW LEVEL ONSHORE
FLOW...AND A MID LEVEL SHORTWAVE UNDERCUTTING THE HIGH...THINK
CHANCE POP IS STILL IN ORDER FOR MON...ESPECIALLY IN
THE AFTERNOON.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS LACK CONSISTENCY RIGHT FROM THE BEGINNING OF THE PERIOD ON
THE STRENGTH OF THE SOUTHERN STREAM CLOSED LOW SHEARING NE MON
NIGHT...AND DISPLACEMENT OF STACKED RIDGING. THIS IS RESULTING IN
DIFFERENCES IN THE NORTHWARD TRACK AND STRENGTH OF THE SURFACE
LOW. WITH THIS UNCERTAINTY HAVE HELD POP TO CHANCE FOR MON NIGHT.
FORECAST DETAILS CONTINUE SHAKY THEREAFTER...WITH UNCERTAINTY IN
PROGRESSION OF PACIFIC SHORTWAVE FEATURES INTO THE LOWER 48.
MODELS HINT AT A PERIOD OF RIDGING TUE INTO WED AS UPPER ENERGY
DIGS OVER THE CENTRAL STATES...WITH LATE A WEEK COASTAL SYSTEM
POSSIBLE AS UPPER ENERGY WORKS TOWARD THE COAST. HAVE CONTINUED
WITH CHANCE POP FOR THIS PERIOD WITH UNCERTAINTY.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
VFR AS HIGH PRESSURE BUILDS INTO THE REGION THROUGH SATURDAY.
WEST/NW WINDS WILL REMAIN AROUND 5 TO 10 KTS...AND THIS WILL CONTINUE
SATURDAY.
OUTLOOK 00Z SUNDAY THROUGH WEDNESDAY...
SAT: VFR.
SUN: VFR.
SUN NIGHT-MON: SUB-VFR.
TUE AND WED...VFR LIKELY.
&&
.MARINE...
SEAS REMAIN ABOVE 5 FT E OF FIRE ISLAND INLET WITH FREQUENT GUSTS
TO 25 KT...SO SCA CONTINUES THERE. OTHERWISE...SUB SCA CONDITIONS
EXPECTED AS WINDS SLOWLY DIMINISH OVERNIGHT.
QUIET CONDITIONS SHOULD THEN BE THE RULE WITH HIGH PRESSURE IN
CONTROL UNTIL LATE SUN NIGHT-MON NIGHT...WHEN INCREASING EASTERLY
FLOW BETWEEN STRONG HIGH PRESSURE TO THE NORTHEAST AND A COASTAL
LOW TO THE SOUTH COULD YIELD SCA CONDITIONS.
WINDS SHOULD DIMINISH ON TUE AS HIGH PRESSURE BUILDS BACK IN...
WITH SEAS SUBSIDING BELOW SCA THROUGH WED.
&&
.HYDROLOGY...
SPREAD IN MODEL QPF IS QUITE LARGE FOR POSSIBLE COASTAL SYSTEM
SUNDAY NIGHT-MON NIGHT...WITH SUPPRESSED SOLUTIONS VIRTUALLY DRY
AND STRONGER/WETTER SOLUTIONS BRINGING OVER AN INCH ESPECIALLY TO
NYC METRO. CURRENT FORECAST LEANS TOWARD THE DRIER SIDE OF THE
ENVELOPE...SO HYDROLOGIC/FLOODING ISSUES APPEAR UNLIKELY ATTM.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR ANZ350-353.
&&
$$
SYNOPSIS...BG/PW
NEAR TERM...BG/PW
SHORT TERM...BG
LONG TERM...NV
AVIATION...PW
MARINE...BG/NV/PW
HYDROLOGY...BG/NV
| 
