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000
FXUS62 KGSP 090257
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
957 PM EST SUN NOV 8 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
ABUNDANT MOISTURE ASSOCIATED WITH IDA IS THEN EXPECTED TO MOVE OVER
THE CAROLINAS AND NORTH GEORGIA AHEAD OF A COLD FRONT ON TUESDAY.
THE FRONT WILL CROSS THE AREA LATE TUESDAY INTO EARLY WEDNESDAY.
HIGH PRESSURE WILL THEN RETURN FOR THE LATTER PART OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
BASED ON LATEST METARS...SATELLITE...RAOBS AND GUIDANCE...FCST IS IN
GOOD SHAPE. NO CHANGES NEEDED THIS EVENING.
PREVIOUS DISCUSSION...
UPPER RIDGE AXIS SLIDES EAST OF THE AREA TONIGHT PRODUCING SLY FLOW
AS SHORT WAVES APPROACH FROM THE WEST. AT THE SFC...THE CENTER OF
HIGH PRESSURE MOVES EAST BUT RIDGING REMAINS OVER THE AREA KEEPING
WINDS LIGHT. CIRRUS WILL SLOWLY INCREASE OVER THE AREA BUT REMAIN
THIN. LOWS END UP NEAR NORMAL MOST LOCATIONS...BUT ABOVE NORMAL IN
THE THERMAL BELT AREAS OF THE UPSTATE.
THERE IS SOME EASTWARD MOVEMENT OF THE UPPER FEATURES MONDAY...BUT
BEST ENERGY REMAINS TO OUR WEST. SFC HIGH PRESSURE RIDGE WEAKENS BUT
REMAINS CENTERED OVER NC. THIS ALLOWS A SLIGHT GRADIENT INCREASE AS
THE TROPICAL APPROACHES FROM THE SOUTH...BUT WINDS REMAIN GENERALLY
LIGHT. INCREASE IN CLOUDS LATE IN THE DAY FROM THE WEST AND SLIGHTLY
LOWER THICKNESSES WILL LEAD TO A COOLING TREND FOR HIGHS. HOWEVER...
THEY WILL STILL BE AS MUCH AS 10 DEGREES ABOVE NORMAL.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 230 PM EDT SUNDAY...THE MODELS BRING A SOUTHERN STREAM SHORTWAVE
EAST ACROSS THE LOWER MS RIVER VALLEY MONDAY NIGHT...WITH THE GFS
REACHING THE AL/MS BORDER TUE MORNING...WHILE THE NAM IS BACK IN
SOUTHERN ARKANSAS. BY TUE EVENING THE GFS SHORTWAVE IS IN EAST TN WHILE
THE NAM IS BACK IN WEST TN. TO COMPLICATE THINGS FURTHER...MOISTURE
ASSOCIATED WITH TROPICAL SYSTEM IDA IS EXPECTED TO BE DRAWN NORTH INTO
THE GULF STATES MONDAY NIGHT. SLIGHT CHANCE POPS WILL BE CARRIED MONDAY
EVENING...WITH POPS INCREASING TO LIKELY IN NORTHEAST GA AND CHANCE
ELSEWHERE OVERNIGHT. THE GFS FASTER TO SPREAD DEEP MOISTURE...
ISENTROPIC UPGLIDE...AND UPSLOPE FLOW INTO THE SOUTHEAST FACING BLUE
RIDGE ESCARPMENT OF NORTHEAST GA AND UPSTATE SC ON TUE...BUT EITHER WAY
IT LOOKS LIKE A WET DAY...AND CATEGORICAL POPS WILL BE CARRIED IN THE
SOUTHWEST PORTION OF THE AREA...TRENDING DOWNWARD TO LIKELY IN THE
CENTRAL PORTION...AND CHANCE IN THE FAR NORTHEAST.
ALTHOUGH DETAILS OF THE END OF THE EVENT VARY BY MODEL...SOME DRYING
FROM THE SOUTHWEST IS INDICATED WEDNESDAY NIGHT. USING A CONSERVATIVE
APPROACH...LIKELY POPS WILL BE MAINTAINED OVER MOST OF THE AREA...
INCLUDING MUCH OF THE TN BORDER...WHERE UPSLOPE FLOW WILL FOLLOW THE
PASSAGE OF THE SURFACE LOW. SOME DECREASE IN POPS IS POSSIBLE ALONG THE
BLUE RIDGE ESCARPMENT AS FLOW BECOMES DOWNSLOPE.
THE DIURNAL TEMPERATURE RANGE WILL BE LIMITED BY CLOUD COVER AND
MOISTURE...AND AN ATTEMPT WAS MADE TO KEEP FORECAST VALUES WITH THE
SUBSTANTIAL SPREAD OF THE MODEL GUIDANCE. AT THIS POINT THE FORECAST
WILL CARRY UP TO THREE INCHES OF RAINFALL ALONG THE GA/SC BLUE RIDGE
ESCARPMENT...PER HPC GUIDANCE. THIS VALUE COULD EASILY BE HIGHER OR
LOWER DEPENDING ON HOW FACTORS COME TOGETHER....BUT THERE DOES SEEM TO
BE BETTER CONSENSUS BACKING HIGHER NUMBERS...AND HEAVY RAINFALL WILL BE
MENTIONED IN THE HAZARDOUS WEATHER OUTLOOK. ANOTHER POTENTIAL HAZARD
WILL BE WINDS APPROACHING ADVISORY CRITERIA AT HIGHER ELEVATIONS ON
TUESDAY...BUT CONFIDENCE IS LOWER THAN IT IS FOR HEAVY RAINFALL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 200 PM SUNDAY...WITH CONSIDERABLE UNCERTAINTY...A LOW OR
TROUGH WHICH CONTAINS THE REMNANT CIRCULATION AND MOISTURE OF IDA
SHOULD BE IN PLACE SOMEWHERE ALONG THE SE COAST OF THE U.S. WED
NIGHT. THE OPERATIONAL GFS APPEARS TOO DEEP...TOO FAR INLAND...AND
TOO FAR NE WITH THE TRANSITIONING SYSTEM WED NIGHT. WILL THUS SHY
AWAY FROM THE WRAP AROUND MOISTURE AND COLD PROFILES ACROSS NW NC
FOR WED NIGHT...AND LEAN TOWARD THE DRIER SREF/GFS ENSEMBLE MEAN
SOLUTIONS AT THE START OF THE PERIOD. ADDITIONAL DRYING IS EXPECTED
THROUGH THU AS SFC HIGH PRES BUILDS DOWN FROM THE NW.
A BROAD RIDGE OF HIGH PRESSURE WILL THEN MOVE OVER THE FORECAST AREA
FROM THE WEST LATE THU INTO THE WEEKEND. SOME SOUTHERLY RETURN FLOW
MOISTURE WILL GRADUALLY DEVELOP INTO THE SRN APPALACHIANS AROUND THE
SFC HIGH PRES...BUT THIS WOULD WARRANT LITTLE MORE THAN MTN SLIGHT
CHANCE POPS SAT AFTN AND LOW END SLIGHT CHC TO CHC POPS SUNDAY AFTN.
TEMPS WILL BE NEAR NORMAL EARLY IN THE PERIOD...BECOMING SLIGHTLY
ABOVE NORMAL OVER THE WEEKEND.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
AT KCLT AND ELSEWHERE...LGT/VRB WND TO CALM OVRNGT...WITH A FEW
CIRRUS STREAMING OVRHD. BASED ON THE TRENDS IN SFC OBS AND A LOOK AT
18Z SOUNDINGS TO THE SOUTH...VSBY RESTRICTIONS DO NOT LOOK
LIKELY...DESPITE GOOD RADIATIONAL COOLING CONDITIONS. KAND AND KAVL
HAVE THE HIGHEST CHANCE OF SOME FOG...BUT WILL NOT ADD MENTION IN
TAFS ATTM.
MONDAY...AS HURRICANE IDA MOVES INTO THE GULF...WNDS WILL BCM NELY
(SELY AT KAVL)...BUT SHUD RMN RATHER LGT THRU THE AFTN. CIRRUS/HIGH
CLOUDS WILL INCR IN COVERAGE...THICKEN AND BEGIN TO LWR SOMEWHAT
DURING THE DAY.
OUTLOOK...A COLD FRONT WILL APPROACH FROM THE WEST...AS IDA
APPROACHES FROM SOUTH INVOF CENTRAL GULF OF MEXICO. THERE IS
UNCERTAINTY ON EXACTLY HOW THE TWO SYSTEMS WILL POSITION THEMSELVES
FROM LATE MONDAY NGT THRU WEDNESDAY WRT THE CAROLINAS. HOWEVER...IT
IS EXPECTED THAT AN INCREASING CHC OF SHWRS AND CIG/VSBY
RESTRICTIONS ARE ON TAP ACRS THE AREA DURING THIS PERIOD. THE FRONT
SHOULD MOVE EAST ON WEDNESDAY WITH VFR CONDITIONS RETURNING.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...ARK/RWH
SHORT TERM...JAT
LONG TERM...HG
AVIATION...ARK
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000
FXUS62 KCHS 090240
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
940 PM EST SUN NOV 8 2009
...THE REMNANTS OF HURRICANE IDA WILL BRING UNSETTLED CONDITIONS
AND A VARIETY OF HAZARDS TO THE REGION THIS WEEK...
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE TONIGHT
THROUGH MONDAY. HURRICANE IDA WILL MOVE NORTH THROUGH THE EASTERN
GULF OF MEXICO AND IS FORECAST TO MAKE LANDFALL ALONG THE NORTHERN
GULF COAST TUESDAY. IDA/S REMNANT LOW WILL MOVE EAST WEDNESDAY AND
WILL EMERGE OFF THE NORTHEAST FLORIDA COAST THURSDAY RESULTING IN
UNSETTLED CONDITIONS ACROSS THE REGION. HIGH PRESSURE WILL THEN
BUILD BACK INTO THE REGION BY FRIDAY AND REMAIN THE DOMINANT
WEATHER FEATURE THROUGH THE UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
LATE SUNDAY EVENING...MOSTLY CLEAR SKIES AND A DECOUPLING BOUNDARY
LAYER SUPPORTED DECENT RADIATIONAL COOLING CONDITIONS AWAY FROM
THE COAST. ADJUSTED TEMPERATURE TRENDS ACCORDINGLY...AND LOWERED
LOW TEMPERATURES A COUPLE OF DEGREES ACROSS INTERIOR SC COUNTIES
AND ACROSS FAR INLAND SECTIONS OF SE GA. ONSHORE FLOW WILL SUPPORT
WARMER TEMPERATURES AT THE COAST...ESPECIALLY ACROSS COASTAL GA.
RADIATIONAL COOLING/LOWERING TEMP/DEWPOINT SPREADS WILL SUPPORT
PATCHY FOG INLAND TONIGHT. A TIGHTENING SURFACE PRESSURE GRADIENT/
INCREASING LOW LEVEL WINDS SHOULD LIMIT FOG COVERAGE/IMPACT.
MEANWHILE...ON THE PERIPHERY OF HIGH PRESSURE CENTERED NORTH OF
THE REGION...STRATOCUMULUS WAS PUSHING INTO COASTAL WATERS AND
OCCASIONALLY INTO COASTAL COUNTIES. THIS REGIME WILL CONTINUE
OVERNIGHT...WITH LOW CLOUDS OCCASIONALLY DEVELOPING INTO/PUSHING
ONSHORE ACROSS COASTAL COUNTIES...AND PERHAPS PENETRATING INLAND
TO SOME DEGREE ACROSS SE GA. MEANWHILE...THE UPPER TROUGH OVER
TX/THE WESTERN GULF WILL PULL THE HIGH CLOUD SHIELD ASSOCIATED
WITH IDA INTO THE REGION FROM S/SW TO N/NE OVERNIGHT.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
THE UPPER RIDGE ACROSS THE SOUTHEAST U.S. WILL BEGIN TO RAPIDLY
BREAKDOWN AND PROPAGATE EAST MONDAY AFTERNOON AS POTENT SHORTWAVE
ENERGY DIGS ACROSS TEXAS AND THE WESTERN GULF OF MEXICO. THE
INCREASING SOUTHERLY FLOW BETWEEN THE UPPER RIDGE AND THE
APPROACHING SHORTWAVE WILL HELP DRIVE HURRICANE IDA NORTHWARD
TOWARDS ACROSS OPEN GULF TOWARDS THE NORTH-CENTRAL GULF COAST. WITH
DIMINISHING SUBSIDENCE ALOFT...THE INCREASING ONSHORE FLOW AND
RESULTING MOISTURE FLUX MAY HELP SUPPORT SOME ISOLATED SHOWER
ACTIVITY OVER THE ATLANTIC WATERS...SOME OF WHICH MAY MAKE A RUN FOR
THE UPPER GEORGIA AND LOWER SOUTH CAROLINA COASTS. BOTH THE NAM AND
SREF SUGGEST THERE IS ENOUGH OF A POTENTIAL FOR SPOTTY MEASURABLE
RAINFALL TO OCCUR MONDAY AFTERNOON...ALBEIT LIGHT...TO JUSTIFY
SLIGHT CHANCE POPS FOR ALL COASTAL ZONES WITH THE EXCEPTION OF
CHARLESTON COUNTY. DRY CONDITIONS SHOULD PREVAIL ELSEWHERE.
INCREASING MID-HIGH LEVEL CLOUD COVER WILL HELP TO LIMIT HIGHS TO
THE 75-77 DEGREE RANGE WITH COOLER CONDITIONS ALONG THE IMMEDIATE
COAST WHERE TEMPERATURES MAY STRUGGLE TO REACH THE UPPER
60S...SIMILAR TO THE PAST SEVERAL DAYS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
MODEL GUIDANCE IS IN POOR AGREEMENT THROUGH THE EXTENDED PERIODS
THIS AFTERNOON...WITH NO SOLUTION DISPLAYING VERY GOOD RUN TO RUN
CONTINUITY AS THEY STRUGGLE TO GET A HANDLE ON THE EVENTUAL
EVOLUTION OF HURRICANE IDA. AS A RESULT...FORECAST CONFIDENCE IS
WELL BELOW NORMAL THROUGHOUT THE EXTENDED PERIOD.
HURRICANE IDA IS FORECAST TO LIFT NORTHWARD THROUGH THE GULF OF
MEXICO AND MAKE LANDFALL ALONG THE NORTHERN GULF COAST TUESDAY
MORNING...THEN SHIFT EASTWARD ALONG THE GEORGIA/FLORIDA BORDER AND
INTO THE ATLANTIC BY THURSDAY MORNING. THE ECMWF SEEMS TO HAVE THE
BEST HANDLE ON THE FORECAST TRACK PROVIDED BY THE HURRICANE
CENTER...AND SEEMS TO BE A GOOD COMPROMISE BETWEEN ALL OF THE OTHER
OPERATIONAL MODEL SOLUTIONS AND WILL BE FOLLOWED CLOSELY THROUGHOUT
THE EXTENDED PERIODS.
AS FOR FORECAST DETAILS...DEEP MOISTURE WILL BEGIN TO INCREASE IN
ADVANCE OF THE TROPICAL CYCLONE MONDAY NIGHT AS LOW LEVEL FLOW
BECOMES MORE ONSHORE. DEEPEST MOISTURE ALONG WITH BEST ISENTROPIC
ASCENT WILL REMAIN WEST OF THE FORECAST AREA THROUGH THE NIGHT...SO
WILL HOLD POPS IN THE CHANCE RANGE FOR NOW. DEEP MOISTURE AND
DYNAMIC FORCING FROM THE PHASING OF AN UPPER LEVEL LOW AND TROPICAL
CYCLONE WILL OVERSPREAD THE AREA TUESDAY THROUGH WEDNESDAY AS THE
REMNANTS OF IDA PASS BY TO THE SOUTH ALONG THE GEORGIA FLORIDA
BORDER...AND WILL CARRY LIKELY OR HIGH CHANCE POPS ALL AREAS TUESDAY
THROUGH WEDNESDAY.
GUIDANCE SOLUTIONS DEVIATE SIGNIFICANTLY WEDNESDAY NIGHT THROUGH THE
UPCOMING WEEKEND...OFFERING UP A NUMBER OF POSSIBILITIES TO HOW THE
PATTERN WILL EVOLVE. SEVERAL SOLUTIONS NOW DEPICT THE REMNANTS OF
IDA DEVELOPING INTO A FAIRLY STRONG WESTERN ATLANTIC LOW FOR THE
LATE WEEK TIME FRAME...WITH THE GFS SHOWING HIGH PRESSURE SETTLING
SOUTHWARD AND BEING THE DOMINANT WEATHER INFLUENCE ON THE FORECAST
AREA. TO TRY AND MINIMIZE ERROR...HAVE FOLLOWED THE ECMWF SOLUTION
WHICH APPEARS TO BE A GOOD MIDDLE OF THE ROAD COMPROMISE BETWEEN THE
VARIOUS OPERATIONAL MODELS. THIS RESULTS IN THE DEVELOPMENT OF A
WESTERN ATLANTIC LOW OFF THE FLORIDA COAST FOR THE LATE WEEK TIME
FRAME WITH HIGH PRESSURE BUILDING NORTH OF THE REGION. AS FOR
FORECAST DETAILS...WILL CARRY SLIGHT CHANCE POPS WEDNESDAY NIGHT TO
ACCOUNT FOR THE MODELS TRENDING SLOWER WITH THE EXIT OF DEEP
MOISTURE DUE TO THE DEVELOPMENT OF A WESTERN ATLANTIC LOW. HAVE THEN
KEPT THE FORECAST RAIN FREE THURSDAY THROUGH SUNDAY...BUT MUCH OF
THIS WILL DEPEND ON THE POSITIONING OF HIGH PRESSURE TO THE NORTH AS
WELL AS THE LOCATION OF THE WESTERN ATLANTIC LOW IF INDEED IT DOES
END UP DEVELOPING.
COASTAL IMPACTS...
SIGNIFICANT BEACH EROSION...INCREASING TIDES...STRONG WINDS AND HIGH
SURF MAY IMPACT THE COASTAL COUNTIES BY MID WEEK...DEPENDING ON THE
EVENTUAL TRACK IDA/S REMNANTS TAKE. HIGH SURF ADVISORIES...WIND
ADVISORIES AND/OR COASTAL FLOOD ADVISORIES MAY EVENTUALLY BE NEEDED.
RESIDENTS OF SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA SHOULD
CONTINUE TO MONITOR NWS FORECASTS AND STATEMENTS THIS WEEK AS A
VARIETY OF HAZARDS COULD IMPACT THE REGION.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
SUNDAY EVENING DEWPOINTS WERE IN THE MID/UPPER 50S NEAR THE COAST.
PER SREF/GFS LAMP GUIDANCE THERE EXISTS A SLIGHTLY GREATER THAN 50
PERCENT CHANCE FOR MVFR VISIBILITY TO DEVELOP AT BOTH TERMINALS
BETWEEN 09Z AND 12Z...AND BRIEF IFR OR LOWER VISIBILITY CANNOT BE
RULED OUT. HOWEVER...INCREASING LOW LEVEL WIND FIELDS WILL LIMIT
THE IMPACT OF FOG. OTHERWISE...VFR CONDITIONS WILL PREVAIL THROUGH
THE 00Z TAF PERIOD...WITH A SLIGHT CHANCE FOR BRIEF VFR LEVEL
CIGS BEFORE 12Z MONDAY. INCREASING LOW LEVEL MOISTURE WILL FAVOR
AN INCREASING CHANCE FOR VFR CEILINGS BEFORE MONDAY EVENING...AND
MVFR CEILINGS CANNOT BE RULED OUT BY LATE IN THE 00Z TAF PERIOD
ESPECIALLY AT KSAV.
EXTENDED AVIATION OUTLOOK....VFR CONDITIONS WILL PREVAIL THROUGH
MONDAY. POTENTIAL FOR MVFR OR IFR CONDITIONS MONDAY NIGHT THROUGH
THURSDAY. LLWS ALSO POSSIBLE WED MORNING. VFR CONDITIONS ARE THEN
EXPECTED THURSDAY NIGHT AND FRIDAY.
&&
.MARINE...
THE SURFACE PRESSURE GRADIENT BETWEEN HURRICANE IDA AND HIGH
PRESSURE TO THE NORTH WILL CONTINUE TO TIGHTEN OVERNIGHT...
AND STRENGTHENING E WINDS/BUILDING SEAS WILL SPREAD ACROSS THE
COASTAL WATERS ESPECIALLY THE GA WATERS. AS OF LATE SUNDAY
EVENING...SEAS AT GRAYS REEF BUOY REMAINED JUST UNDER 4 FT...AND
SEAS AT BUOY 41012 EAST OF ST AUGUSTINE FL REMAINED UNDER 6 FT.
THUS...DELAYED THE ONSET OF 6-7 FT SEAS A FEW HOURS ACROSS AMZ374
BUT OTHERWISE CONTINUED ONGOING SMALL CRAFT ADVISORIES WITHOUT
CHANGE.
MARINE CONDITIONS WILL CONTINUE TO SLOWLY DETERIORATE MONDAY AS
COMBINED SEAS INCREASE IN RESPONSE TO THE STRENGTHENING FLOW
BETWEEN IDA AND HIGH PRESSURE TO THE NORTH. SEAS ARE EXPECTED TO
REACH 6 FT ACROSS THE NEARSHORE WATERS SOUTH OF EDISTO BEACH BY
EARLY TO MID AFTERNOON MONDAY AND SINCE THIS IS WITHIN THE SECOND
PERIOD SMALL CRAFT FLAGS WILL BE HOISTED FOR AMZ352-354. LOOKS
LIKE SEAS WILL REMAIN 4-5 FT FOR THE CHARLESTON COUNTY WATERS
NORTH OF EDISTO BEACH WITH SMALL CRAFT ADVISORY CONDITIONS LIKELY
HOLDING OFF UNTIL MONDAY NIGHT. SEAS WILL CONTINUE TO BUILD TO 6-8
FT OVER THE GEORGIA OFFSHORE LEG...CREATING VERY HAZARDOUS
CONDITIONS.
MONDAY NIGHT THROUGH FRIDAY...HURRICANE IDA IS FORECAST TO LIFT
NORTHWARD THROUGH THE GULF OF MEXICO AND MAKE LANDFALL ALONG THE
NORTHERN GULF COAST TUESDAY MORNING. THE SYSTEM IS THEN EXPECTED
TO WEAKEN AS IT TRACKS ALONG THE GEORGIA/FLORIDA BORDER AND INTO
THE WESTERN ATLANTIC BY THURSDAY MORNING. AS STRONG PRESSURE
GRADIENT IS EXPECTED TO RESULT ACROSS THE COASTAL WATERS THROUGH
THE FORECAST PERIOD AS HIGH PRESSURE BUILDS NORTH OF THE REGION
AND THE REMNANTS OF IDA SLIDE BY TO THE SOUTH. SMALL CRAFT
CONDITIONS ARE EXPECTED ACROSS ALL WATERS MONDAY NIGHT THROUGH
THURSDAY...WITH PORTIONS OF THE WATERS POSSIBLY SEEING SMALL CRAFT
CONDITIONS THROUGH FRIDAY. SMALL CRAFT CONDITIONS ARE EXPECTED IN
CHARLESTON HARBOR WEDNESDAY AFTERNOON THROUGH THURSDAY.
DEPENDING ON HOW STRONG THE GRADIENT ENDS UP BECOMING...THERE
REMAINS THE POTENTIAL FOR GALE FORCE CONDITIONS TO IMPACT PORTIONS
OF THE WATERS WEDNESDAY THROUGH THURSDAY EVENING. GALE WATCHES AND
WARNINGS MAY EVENTUALLY BE NEEDED.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM NOON MONDAY TO 5 AM EST FRIDAY FOR
AMZ352.
SMALL CRAFT ADVISORY UNTIL 7 AM EST SATURDAY FOR AMZ374.
SMALL CRAFT ADVISORY FROM 5 PM MONDAY TO NOON EST FRIDAY FOR
AMZ350.
SMALL CRAFT ADVISORY FROM NOON MONDAY TO 5 PM EST THURSDAY FOR
AMZ354.
&&
$$
000
FXUS62 KCHS 082347
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
647 PM EST SUN NOV 8 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH
MONDAY AS HURRICANE IDA MOVES NORTH INTO THE GULF OF MEXICO.
IDA IS FORECAST TO MAKE LANDFALL ALONG THE NORTHERN GULF COAST
TUESDAY. IDA/S REMNANT LOW WILL MOVE EAST WEDNESDAY AND EMERGE
OFF THE NORTHEAST FLORIDA COAST THURSDAY RESULTING IN UNSETTLED
CONDITIONS ACROSS THE REGION. HIGH PRESSURE WILL THEN BUILD BACK
INTO THE REGION BY FRIDAY AND REMAIN THE DOMINANT WEATHER FEATURE
THROUGH THE UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
RELATIVELY QUIET AND DRY WEATHER WILL PERSIST TONIGHT AS HIGH
PRESSURE BOTH AT THE SURFACE AND ALOFT HOLDS ITS INFLUENCE OVER
THE REGION.
VISIBLE SATELLITE IMAGES SHOW EXTENSIVE CLOSED CELL STRATOCUMULUS
LURKING OVER MUCH OF THE OFFSHORE WATERS ALONG THE WESTERN WALL
OF THE GULF STREAM. MODELS SUGGEST MOST OF THE STRATOCUMULUS WILL
REMAIN OFFSHORE TONIGHT AS THE CELLS TRY AND PROPAGATE TO THE WEST
OVER THE RELATIVELY COOLER NEARSHORE WATERS...HOWEVER WE CAN NOT
COMPLETELY RULE OUT A FEW PATCHES MOVING ONSHORE AFTER MIDNIGHT AS
THE ONSHORE FLOW DEEPENS...MAINLY FROM HILTON HEAD SOUTH TO TYBEE
ISLAND AND SAPELO ISLAND. CIRRUS BLOW OFF FROM HURRICANE IDA WILL
ALSO INCREASE LATE...MAINLY ACROSS SOUTHEAST GEORGIA. PLAN TO
KEEP SKIES CLEAR TO MOSTLY CLEAR THIS EVENING...BECOMING PARTLY
CLOUDY FOR THE SOUTHEAST GEORGIA ZONES WELL AFTER MIDNIGHT.
TEMPERATURES WILL FALL QUICKLY SUN EVENING AS WINDS DECOUPLE. THE
GRADIENT IS FORECAST TO TIGHTEN A BIT OVERNIGHT AS IDA MOVES NORTH
INTO THE GULF OF MEXICO AND HIGH PRESSURE HOLDS FIRM WELL
OFFSHORE. THIS MAY BE ENOUGH TO SUPPORT A RECOUPLING OF THE
BOUNDARY LAYER ALONG THE COAST AND SOUTH OF INTERSTATE 16 OVERNIGHT.
THIS COMBINED WITH A PERSISTENT ONSHORE FLOW AND INCREASING CIRRUS
ALOFT SHOULD HELP MODERATE OVERNIGHT TEMPERATURES
SOMEWHAT...EXCEPT WELL INLAND WHERE COMPLETE DECOUPLING WILL
LIKELY PERSIST THROUGH SUNRISE MONDAY. WILL SEE A LARGE
TEMPERATURE GRADIENT ACROSS THE FORECAST AREA AS A RESULT WITH
LOWS RANGING FROM THE UPPER 40S WELL INLAND TO THE MID 60S ALONG
THE BEACH FRONT.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
THE UPPER RIDGE ACROSS THE SOUTHEAST U.S. WILL BEGIN TO RAPIDLY
BREAKDOWN AND PROPAGATE EAST MONDAY AFTERNOON AS POTENT SHORTWAVE
ENERGY DIGS ACROSS TEXAS AND THE WESTERN GULF OF MEXICO. THE
INCREASING SOUTHERLY FLOW BETWEEN THE UPPER RIDGE AND THE
APPROACHING SHORTWAVE WILL HELP DRIVE HURRICANE IDA NORTHWARD
TOWARDS ACROSS OPEN GULF TOWARDS THE NORTH-CENTRAL GULF COAST. WITH
DIMINISHING SUBSIDENCE ALOFT...THE INCREASING ONSHORE FLOW AND
RESULTING MOISTURE FLUX MAY HELP SUPPORT SOME ISOLATED SHOWER
ACTIVITY OVER THE ATLANTIC WATERS...SOME OF WHICH MAY MAKE A RUN FOR
THE UPPER GEORGIA AND LOWER SOUTH CAROLINA COASTS. BOTH THE NAM AND
SREF SUGGEST THERE IS ENOUGH OF A POTENTIAL FOR SPOTTY MEASURABLE
RAINFALL TO OCCUR MONDAY AFTERNOON...ALBEIT LIGHT...TO JUSTIFY
SLIGHT CHANCE POPS FOR ALL COASTAL ZONES WITH THE EXCEPTION OF
CHARLESTON COUNTY. DRY CONDITIONS SHOULD PREVAIL ELSEWHERE.
INCREASING MID-HIGH LEVEL CLOUD COVER WILL HELP TO LIMIT HIGHS TO
THE 75-77 DEGREE RANGE WITH COOLER CONDITIONS ALONG THE IMMEDIATE
COAST WHERE TEMPERATURES MAY STRUGGLE TO REACH THE UPPER
60S...SIMILAR TO THE PAST SEVERAL DAYS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
MODEL GUIDANCE IS IN POOR AGREEMENT THROUGH THE EXTENDED PERIODS
THIS AFTERNOON...WITH NO SOLUTION DISPLAYING VERY GOOD RUN TO RUN
CONTINUITY AS THEY STRUGGLE TO GET A HANDLE ON THE EVENTUAL
EVOLUTION OF HURRICANE IDA. AS A RESULT...FORECAST CONFIDENCE IS
WELL BELOW NORMAL THROUGHOUT THE EXTENDED PERIOD.
HURRICANE IDA IS FORECAST TO LIFT NORTHWARD THROUGH THE GULF OF
MEXICO AND MAKE LANDFALL ALONG THE NORTHERN GULF COAST TUESDAY
MORNING...THEN SHIFT EASTWARD ALONG THE GEORGIA/FLORIDA BORDER AND
INTO THE ATLANTIC BY THURSDAY MORNING. THE ECMWF SEEMS TO HAVE THE
BEST HANDLE ON THE FORECAST TRACK PROVIDED BY THE HURRICANE
CENTER...AND SEEMS TO BE A GOOD COMPROMISE BETWEEN ALL OF THE OTHER
OPERATIONAL MODEL SOLUTIONS AND WILL BE FOLLOWED CLOSELY THROUGHOUT
THE EXTENDED PERIODS.
AS FOR FORECAST DETAILS...DEEP MOISTURE WILL BEGIN TO INCREASE IN
ADVANCE OF THE TROPICAL CYCLONE MONDAY NIGHT AS LOW LEVEL FLOW
BECOMES MORE ONSHORE. DEEPEST MOISTURE ALONG WITH BEST ISENTROPIC
ASCENT WILL REMAIN WEST OF THE FORECAST AREA THROUGH THE NIGHT...SO
WILL HOLD POPS IN THE CHANCE RANGE FOR NOW. DEEP MOISTURE AND
DYNAMIC FORCING FROM THE PHASING OF AN UPPER LEVEL LOW AND TROPICAL
CYCLONE WILL OVERSPREAD THE AREA TUESDAY THROUGH WEDNESDAY AS THE
REMNANTS OF IDA PASS BY TO THE SOUTH ALONG THE GEORGIA FLORIDA
BORDER...AND WILL CARRY LIKELY OR HIGH CHANCE POPS ALL AREAS TUESDAY
THROUGH WEDNESDAY.
GUIDANCE SOLUTIONS DEVIATE SIGNIFICANTLY WEDNESDAY NIGHT THROUGH THE
UPCOMING WEEKEND...OFFERING UP A NUMBER OF POSSIBILITIES TO HOW THE
PATTERN WILL EVOLVE. SEVERAL SOLUTIONS NOW DEPICT THE REMNANTS OF
IDA DEVELOPING INTO A FAIRLY STRONG WESTERN ATLANTIC LOW FOR THE
LATE WEEK TIME FRAME...WITH THE GFS SHOWING HIGH PRESSURE SETTLING
SOUTHWARD AND BEING THE DOMINANT WEATHER INFLUENCE ON THE FORECAST
AREA. TO TRY AND MINIMIZE ERROR...HAVE FOLLOWED THE ECMWF SOLUTION
WHICH APPEARS TO BE A GOOD MIDDLE OF THE ROAD COMPROMISE BETWEEN THE
VARIOUS OPERATIONAL MODELS. THIS RESULTS IN THE DEVELOPMENT OF A
WESTERN ATLANTIC LOW OFF THE FLORIDA COAST FOR THE LATE WEEK TIME
FRAME WITH HIGH PRESSURE BUILDING NORTH OF THE REGION. AS FOR
FORECAST DETAILS...WILL CARRY SLIGHT CHANCE POPS WEDNESDAY NIGHT TO
ACCOUNT FOR THE MODELS TRENDING SLOWER WITH THE EXIT OF DEEP
MOISTURE DUE TO THE DEVELOPMENT OF A WESTERN ATLANTIC LOW. HAVE THEN
KEPT THE FORECAST RAIN FREE THURSDAY THROUGH SUNDAY...BUT MUCH OF
THIS WILL DEPEND ON THE POSITIONING OF HIGH PRESSURE TO THE NORTH AS
WELL AS THE LOCATION OF THE WESTERN ATLANTIC LOW IF INDEED IT DOES
END UP DEVELOPING.
COASTAL IMPACTS...
SIGNIFICANT BEACH EROSION...INCREASING TIDES...STRONG WINDS AND HIGH
SURF MAY IMPACT THE COASTAL COUNTIES BY MID WEEK...DEPENDING ON THE
EVENTUAL TRACK IDA/S REMNANTS TAKE. HIGH SURF ADVISORIES...WIND
ADVISORIES AND/OR COASTAL FLOOD ADVISORIES MAY EVENTUALLY BE NEEDED.
RESIDENTS OF SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA SHOULD
CONTINUE TO MONITOR NWS FORECASTS AND STATEMENTS THIS WEEK AS A
VARIETY OF HAZARDS COULD IMPACT THE REGION.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
SUNDAY EVENING DEWPOINTS WERE IN THE MID/UPPER 50S NEAR THE COAST.
PER SREF/GFS LAP GUIDANCE THERE EXISTS A SLIGHTLY GREATER THAN 50
PERCENT CHANCE FOR MVFR VISIBILITY TO DEVELOP AT BOTH TERMINALS
BETWEEN 09Z AND 12Z...AND BRIEF IFR OR LOWER VISIBILITY CANNOT BE
RULED OUT. HOWEVER...INCREASING LOW LEVEL WIND FIELDS WILL LIMIT
THE IMPACT OF FOG. OTHERWISE...VFR CONDITIONS WILL PREVAIL THROUGH
THE 00Z TAF PERIOD. INCREASING LOW LEVEL MOISTURE WILL FAVOR VFR
CEILINGS BEFORE MONDAY EVENING...AND MVFR CEILINGS CANNOT BE RULED
OUT BY LATE IN THE 00Z TAF PERIOD ESPECIALLY AT KSAV.
EXTENDED AVIATION OUTLOOK....VFR CONDITIONS WILL PREVAIL THROUGH
MONDAY. POTENTIAL FOR MVFR OR IFR CONDITIONS MONDAY NIGHT THROUGH
THURSDAY. LLWS ALSO POSSIBLE WED MORNING. VFR CONDITIONS ARE THEN
EXPECTED THURSDAY NIGHT AND FRIDAY.
&&
.MARINE...
AS THE SURFACE PRESSURE GRADIENT BETWEEN HURRICANE IDA AND HIGH
PRESSURE TO THE NORTH TIGHTENS....STRENGTHENING WINDS/BUILDING
SEAS WILL SPREAD ACROSS THE GEORGIA WATERS OVERNIGHT AS THE
GRADIENT THIS FAR NORTH BEGINS TO RESPOND TO IDA/S CONTINUED
NORTHWARD MOVEMENT. THE HIGHEST WINDS LOOK TO REMAIN OVER THE
GEORGIA OFFSHORE WATERS WERE WINDS WILL INCREASE TO 15-20 KT WHILE
10-15 KT SHOULD PREVAIL OVER THE NEARSHORE WATERS. ITS BEEN
DIFFICULT TO DETERMINE SEAS THIS AFTERNOON WITH THE LACK OF BUOY
AND PILOT BOAT OBSERVATIONS ACROSS THE LOCAL MARINE AREA. SEAS AT
41008 HAVE BEEN HOLDING AROUND 4 FT SINCE LATE MORNING WHICH IS A
LITTLE AHEAD OF THE LATEST WW4 OUTPUT. PLAN TO STAY ABOUT 0.5 TO 1
FT AHEAD OF WW4 GUIDANCE FOR TONIGHT WHICH WOULD PLACE 4-6 FT SEAS
IN THE GEORGIA OFFSHORE WATERS BY MID EVENING...BUILDING TO 5-7 FT
LATE. THE CURRENT SMALL CRAFT ADVISORY THERE LOOKS ON TRACK. SEAS
WILL BUILD TO 3-4 FT OVER THE SOUTH CAROLINA NEARSHORE WATERS AND
4-5 FT OVER THE GEORGIA NEARSHORE WATERS.
MARINE CONDITIONS WILL CONTINUE TO SLOWLY DETERIORATE MONDAY AS
COMBINED SEAS INCREASE IN RESPONSE TO THE STRENGTHENING FLOW
BETWEEN IDA AND HIGH PRESSURE TO THE NORTH. SEAS ARE EXPECTED TO
REACH 6 FT ACROSS THE NEARSHORE WATERS SOUTH OF EDISTO BEACH BY
EARLY TO MID AFTERNOON MONDAY AND SINCE THIS IS WITHIN THE SECOND
PERIOD SMALL CRAFT FLAGS WILL BE HOISTED FOR AMZ352-354. LOOKS
LIKE SEAS WILL REMAIN 4-5 FT FOR THE CHARLESTON COUNTY WATERS
NORTH OF EDISTO BEACH WITH SMALL CRAFT ADVISORY CONDITIONS LIKELY
HOLDING OFF UNTIL MONDAY NIGHT. SEAS WILL CONTINUE TO BUILD TO 6-8
FT OVER THE GEORGIA OFFSHORE LEG...CREATING VERY HAZARDOUS
CONDITIONS.
MONDAY NIGHT THROUGH FRIDAY...HURRICANE IDA IS FORECAST TO LIFT
NORTHWARD THROUGH THE GULF OF MEXICO AND MAKE LANDFALL ALONG THE
NORTHERN GULF COAST TUESDAY MORNING. THE SYSTEM IS THEN EXPECTED
TO WEAKEN AS IT TRACKS ALONG THE GEORGIA/FLORIDA BORDER AND INTO
THE WESTERN ATLANTIC BY THURSDAY MORNING. AS STRONG PRESSURE
GRADIENT IS EXPECTED TO RESULT ACROSS THE COASTAL WATERS THROUGH
THE FORECAST PERIOD AS HIGH PRESSURE BUILDS NORTH OF THE REGION
AND THE REMNANTS OF IDA SLIDE BY TO THE SOUTH. SMALL CRAFT
CONDITIONS ARE EXPECTED ACROSS ALL WATERS MONDAY NIGHT THROUGH
THURSDAY...WITH PORTIONS OF THE WATERS POSSIBLY SEEING SMALL CRAFT
CONDITIONS THROUGH FRIDAY. SMALL CRAFT CONDITIONS ARE EXPECTED IN
CHARLESTON HARBOR WEDNESDAY AFTERNOON THROUGH THURSDAY.
DEPENDING ON HOW STRONG THE GRADIENT ENDS UP BECOMING...THERE
REMAINS THE POTENTIAL FOR GALE FORCE CONDITIONS TO IMPACT PORTIONS
OF THE WATERS WEDNESDAY THROUGH THURSDAY EVENING. GALE WATCHES AND
WARNINGS MAY EVENTUALLY BE NEEDED.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM NOON MONDAY TO 5 AM EST FRIDAY FOR
AMZ352.
SMALL CRAFT ADVISORY UNTIL 7 AM EST SATURDAY FOR AMZ374.
SMALL CRAFT ADVISORY FROM 5 PM MONDAY TO NOON EST FRIDAY FOR
AMZ350.
SMALL CRAFT ADVISORY FROM NOON MONDAY TO 5 PM EST THURSDAY FOR
AMZ354.
&&
$$
000
FXUS62 KGSP 082335
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
635 PM EST SUN NOV 8 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
ABUNDANT MOISTURE ASSOCIATED WITH IDA IS THEN EXPECTED TO MOVE
OVER THE CAROLINAS AND NORTH GEORGIA AHEAD OF A COLD FRONT ON
TUESDAY. THE FRONT WILL CROSS THE AREA LATE TUESDAY INTO EARLY
WEDNESDAY. HIGH PRESSURE WILL THEN RETURN FOR THE LATTER PART OF
THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
UPPER RIDGE AXIS SLIDES EAST OF THE AREA TONIGHT PRODUCING SLY FLOW
AS SHORT WAVES APPROACH FROM THE WEST. AT THE SFC...THE CENTER OF
HIGH PRESSURE MOVES EAST BUT RIDGING REMAINS OVER THE AREA KEEPING
WINDS LIGHT. CIRRUS WILL SLOWLY INCREASE OVER THE AREA BUT REMAIN
THIN. LOWS END UP NEAR NORMAL MOST LOCATIONS...BUT ABOVE NORMAL IN
THE THERMAL BELT AREAS OF THE UPSTATE.
THERE IS SOME EASTWARD MOVEMENT OF THE UPPER FEATURES MONDAY...BUT
BEST ENERGY REMAINS TO OUR WEST. SFC HIGH PRESSURE RIDGE WEAKENS BUT
REMAINS CENTERED OVER NC. THIS ALLOWS A SLIGHT GRADIENT INCREASE AS
THE TROPICAL APPROACHES FROM THE SOUTH...BUT WINDS REMAIN GENERALLY
LIGHT. INCREASE IN CLOUDS LATE IN THE DAY FROM THE WEST AND SLIGHTLY
LOWER THICKNESSES WILL LEAD TO A COOLING TREND FOR HIGHS. HOWEVER...
THEY WILL STILL BE AS MUCH AS 10 DEGREES ABOVE NORMAL.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 230 PM EDT SUNDAY...THE MODELS BRING A SOUTHERN STREAM SHORTWAVE
EAST ACROSS THE LOWER MS RIVER VALLEY MONDAY NIGHT...WITH THE GFS
REACHING THE AL/MS BORDER TUE MORNING...WHILE THE NAM IS BACK IN
SOUTHERN ARKANSAS. BY TUE EVENING THE GFS SHORTWAVE IS IN EAST TN WHILE
THE NAM IS BACK IN WEST TN. TO COMPLICATE THINGS FURTHER...MOISTURE
ASSOCIATED WITH TROPICAL SYSTEM IDA IS EXPECTED TO BE DRAWN NORTH INTO
THE GULF STATES MONDAY NIGHT. SLIGHT CHANCE POPS WILL BE CARRIED MONDAY
EVENING...WITH POPS INCREASING TO LIKELY IN NORTHEAST GA AND CHANCE
ELSEWHERE OVERNIGHT. THE GFS FASTER TO SPREAD DEEP MOISTURE...
ISENTROPIC UPGLIDE...AND UPSLOPE FLOW INTO THE SOUTHEAST FACING BLUE
RIDGE ESCARPMENT OF NORTHEAST GA AND UPSTATE SC ON TUE...BUT EITHER WAY
IT LOOKS LIKE A WET DAY...AND CATEGORICAL POPS WILL BE CARRIED IN THE
SOUTHWEST PORTION OF THE AREA...TRENDING DOWNWARD TO LIKELY IN THE
CENTRAL PORTION...AND CHANCE IN THE FAR NORTHEAST.
ALTHOUGH DETAILS OF THE END OF THE EVENT VARY BY MODEL...SOME DRYING
FROM THE SOUTHWEST IS INDICATED WEDNESDAY NIGHT. USING A CONSERVATIVE
APPROACH...LIKELY POPS WILL BE MAINTAINED OVER MOST OF THE AREA...
INCLUDING MUCH OF THE TN BORDER...WHERE UPSLOPE FLOW WILL FOLLOW THE
PASSAGE OF THE SURFACE LOW. SOME DECREASE IN POPS IS POSSIBLE ALONG THE
BLUE RIDGE ESCARPMENT AS FLOW BECOMES DOWNSLOPE.
THE DIURNAL TEMPERATURE RANGE WILL BE LIMITED BY CLOUD COVER AND
MOISTURE...AND AN ATTEMPT WAS MADE TO KEEP FORECAST VALUES WITH THE
SUBSTANTIAL SPREAD OF THE MODEL GUIDANCE. AT THIS POINT THE FORECAST
WILL CARRY UP TO THREE INCHES OF RAINFALL ALONG THE GA/SC BLUE RIDGE
ESCARPMENT...PER HPC GUIDANCE. THIS VALUE COULD EASILY BE HIGHER OR
LOWER DEPENDING ON HOW FACTORS COME TOGETHER....BUT THERE DOES SEEM TO
BE BETTER CONSENSUS BACKING HIGHER NUMBERS...AND HEAVY RAINFALL WILL BE
MENTIONED IN THE HAZARDOUS WEATHER OUTLOOK. ANOTHER POTENTIAL HAZARD
WILL BE WINDS APPROACHING ADVISORY CRITERIA AT HIGHER ELEVATIONS ON
TUESDAY...BUT CONFIDENCE IS LOWER THAN IT IS FOR HEAVY RAINFALL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 200 PM SUNDAY...WITH CONSIDERABLE UNCERTAINTY...A LOW OR
TROUGH WHICH CONTAINS THE REMNANT CIRCULATION AND MOISTURE OF IDA
SHOULD BE IN PLACE SOMEWHERE ALONG THE SE COAST OF THE U.S. WED
NIGHT. THE OPERATIONAL GFS APPEARS TOO DEEP...TOO FAR INLAND...AND
TOO FAR NE WITH THE TRANSITIONING SYSTEM WED NIGHT. WILL THUS SHY
AWAY FROM THE WRAP AROUND MOISTURE AND COLD PROFILES ACROSS NW NC
FOR WED NIGHT...AND LEAN TOWARD THE DRIER SREF/GFS ENSEMBLE MEAN
SOLUTIONS AT THE START OF THE PERIOD. ADDITIONAL DRYING IS EXPECTED
THROUGH THU AS SFC HIGH PRES BUILDS DOWN FROM THE NW.
A BROAD RIDGE OF HIGH PRESSURE WILL THEN MOVE OVER THE FORECAST AREA
FROM THE WEST LATE THU INTO THE WEEKEND. SOME SOUTHERLY RETURN FLOW
MOISTURE WILL GRADUALLY DEVELOP INTO THE SRN APPALACHIANS AROUND THE
SFC HIGH PRES...BUT THIS WOULD WARRANT LITTLE MORE THAN MTN SLIGHT
CHANCE POPS SAT AFTN AND LOW END SLIGHT CHC TO CHC POPS SUNDAY AFTN.
TEMPS WILL BE NEAR NORMAL EARLY IN THE PERIOD...BECOMING SLIGHTLY
ABOVE NORMAL OVER THE WEEKEND.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
AT KCLT AND ELSEWHERE...LGT/VRB WND TO CALM OVRNGT...WITH A FEW
CIRRUS STREAMING OVRHD. BASED ON THE TRENDS IN SFC OBS AND A LOOK AT
18Z SOUNDINGS TO THE SOUTH...VSBY RESTRICTIONS DO NOT LOOK
LIKELY...DESPITE GOOD RADIATIONAL COOLING CONDITIONS. KAND AND KAVL
HAVE THE HIGHEST CHANCE OF SOME FOG...BUT WILL NOT ADD MENTION IN
TAFS ATTM.
MONDAY...AS HURRICANE IDA MOVES INTO THE GULF...WNDS WILL BCM NELY
(SELY AT KAVL)...BUT SHUD RMN RATHER LGT THRU THE AFTN. CIRRUS/HIGH
CLOUDS WILL INCR IN COVERAGE...THICKEN AND BEGIN TO LWR SOMEWHAT
DURING THE DAY.
OUTLOOK...A COLD FRONT WILL APPROACH FROM THE WEST...AS IDA
APPROACHES FROM SOUTH INVOF CENTRAL GULF OF MEXICO. THERE IS
UNCERTAINTY ON EXACTLY HOW THE TWO SYSTEMS WILL POSITION THEMSELVES
FROM LATE MONDAY NGT THRU WEDNESDAY WRT THE CAROLINAS. HOWEVER...IT
IS EXPECTED THAT AN INCREASING CHC OF SHWRS AND CIG/VSBY
RESTRICTIONS ARE ON TAP ACRS THE AREA DURING THIS PERIOD. THE FRONT
SHOULD MOVE EAST ON WEDNESDAY WITH VFR CONDITIONS RETURNING.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...RWH
SHORT TERM...JAT
LONG TERM...HG
AVIATION...ARK
[top]
000
FXUS62 KCAE 082331
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
631 PM EST SUN NOV 8 2009
.SYNOPSIS...
DRY HIGH PRESSURE EXTENDING INTO THE FORECAST AREA WILL CONTINUE TO
DOMINATE THROUGH MONDAY. A COLD FRONT ALONG WITH A SURGE OF TROPICAL
MOISTURE WILL AFFECT THE AREA MAINLY TUESDAY AND TUESDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
DRY HIGH PRESSURE ACROSS THE AREA TONIGHT...ONLY SOME HIGH LEVEL
CLOUDS MAINLY AFTER MIDNIGHT. TEMPERATURES SLIGHTLY WARMER THAN
PREVIOUS NIGHTS ALTHOUGH WITH GOOD RADIATIONAL COOLING PREFER MAV
GUIDANCE.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
LITTLE CHANGE MADE FROM PREVIOUS FORECAST. CONSIDERABLE
UNCERTAINTY NOTED IN THE ENSEMBLE GUIDANCE. THE MODELS AGREE KEEPING
DRY HIGH PRESSURE IN CONTROL THROUGH MONDAY. THE MAIN PROBLEM IS
THE IMPACT OF TROPICAL MOISTURE ASSOCIATED WITH IDA. CONFIDENCE
REMAINS LOW BECAUSE OF LARGE SPREAD IN THE MODELS. UPPER TROUGH
MOVING ACROSS THE SOUTHERN PLAINS WILL MOVE INTO THE GULF COAST
REGION TUESDAY AND POSSIBLY AFFECT MOVEMENT OF IDA. NAM REMAINS
SLOWER MOVING IDA INLAND WITH SREF POPS HIGHER ACROSS
GEORGIA/ALABAMA. GFS APPEARS TO BE AN OUTLIER IN THE MREF. BOTH
GFS/NAM INDICATE INCREASING ISENTROPIC LIFT/MOISTURE FLUX
TUESDAY/TUESDAY NIGHT SO WILL INCREASE POPS SLIGHTLY. COULD BE
HEAVY RAIN ASSOCIATED WITH TROPICAL MOISTURE FLUX. MODELS SHOW
STRONG VERTICAL WIND SHEAR BUT TIMING DIFFERENT. 30 TO 50 KT 850MB
JET POSSIBLE AND ELEVATED INSTABILITY NOTED.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
TROPICAL SYSTEM MAY LINGER IN THE AREA WEDNESDAY...CONSIDERABLE
UNCERTAINTY AT THIS TIME. WILL KEEP LOW CHANCE POPS WITH AREA OF
LOW PRESSURE ALONG COASTAL FRONT AND CLOUDINESS LINGERING IN THE
MIDLANDS THROUGH EARLY AFTERNOON. HIGH PRESSURE IN THE GREAT LAKES
BUILDING SOUTHEAST...SHOULD BE DRY THURSDAY THROUGH WEEKEND WITH
TEMPERATURES NEAR OR SLIGHTLY ABOVE CLIMATOLOGY.
&&
.AVIATION /00Z MONDAY THROUGH SATURDAY/...
DRY HIGH PRESSURE ANCHORED ACROSS EASTERN VIRGINIA/NORTH CAROLINA
WILL REMAIN THE DOMINANT WEATHER FACTOR THROUGH THE TAF PERIOD.
MODEL TIME SECTIONS SHOW RELATIVELY LIGHT WINDS ALONG WITH DRY
CONDITIONS OVERNIGHT. MODEL/LAMP GUIDANCE SUGGEST POTENTIAL FOR SOME
MVFR FOG AT BOTH AGS/OGB BY MORNING. EXPECT CLEAR SKIES
TONIGHT...WITH SOME MVFR FOG POSSIBLE AT AGS AND OGB. SOME CIRRUS
POSSIBLE AFTER SUNRISE MONDAY MORNING. SFC WINDS EXPECTED TO BECOME
CALM AND REMAIN NEAR CALM OVERNIGHT...THEN BECOMING LIGHT NE AFTER
14Z MONDAY.
EXTENDED AVIATION OUTLOOK...STILL SOME UNCERTAINTY CONCERNING THE
FUTURE TRACK OF HURRICANE IDA TUESDAY INTO WEDNESDAY. AT THIS
TIME...THINK THERE WILL BE WIDESPREAD CEILING AND VISIBILITY
RESTRICTIONS ACROSS THE AREA TUESDAY INTO WEDNESDAY ASSOCIATED WITH
ISENTROPIC LIFT.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
000
FXUS62 KCHS 082128 CCA
AFDCHS
AREA FORECAST DISCUSSION...CORRECTION
NATIONAL WEATHER SERVICE CHARLESTON SC
405 PM EST SUN NOV 8 2009
...THE REMNANTS OF HURRICANE IDA WILL BRING UNSETTLED CONDITIONS
AND A VARIETY OF HAZARDS TO THE REGION THIS WEEK...
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH
MONDAY AS HURRICANE IDA MOVES NORTH INTO THE GULF OF MEXICO.
IDA IS FORECAST TO MAKE LANDFALL ALONG THE NORTHERN GULF COAST
TUESDAY. IDA/S REMNANT LOW WILL MOVE EAST WEDNESDAY AND EMERGE
OFF THE NORTHEAST FLORIDA COAST THURSDAY RESULTING IN UNSETTLED
CONDITIONS ACROSS THE REGION. HIGH PRESSURE WILL THEN BUILD BACK
INTO THE REGION BY FRIDAY AND REMAIN THE DOMINANT WEATHER FEATURE
THROUGH THE UPCOMING WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
RELATIVELY QUIET AND DRY WEATHER WILL PERSIST INTO TONIGHT AS HIGH
PRESSURE BOTH AT THE SURFACE AND ALOFT HOLDS ITS INFLUENCE OVER
THE REGION. THE SHALLOW CUMULUS FIELD WHICH HAS DEVELOPED OVER
PARTS OF INTERIOR SOUTHEAST GEORGIA WILL QUICKLY DISSIPATE OVER
THE NEXT 1-2 HOURS AS HEATING WANES WITH THE APPROACH OF SUNSET.
VISIBLE SATELLITE IMAGES SHOW EXTENSIVE CLOSED CELL STRATOCUMULUS
LURKING OVER MUCH OF THE OFFSHORE WATERS ALONG THE WESTERN WALL
OF THE GULF STREAM. MODELS SUGGEST MOST OF THE STRATOCUMULUS WILL
REMAIN OFFSHORE TONIGHT AS THE CELLS TRY AND PROPAGATE TO THE WEST
OVER THE RELATIVELY COOLER NEARSHORE WATERS...HOWEVER WE CAN NOT
COMPLETELY RULE OUT A FEW PATCHES MOVING ONSHORE AFTER MIDNIGHT AS
THE ONSHORE FLOW DEEPENS--MAINLY FROM HILTON HEAD SOUTH TO TYBEE
ISLAND AND SAPELO ISLAND. CIRRUS BLOW OFF FROM HURRICANE IDA WILL
ALSO BE ON THE INCREASE LATE...MAINLY ACROSS SOUTHEAST GEORGIA. PLAN
TO KEEP SKIES CLEAR TO MOSTLY CLEAR THIS EVENING...BECOMING PARTLY
CLOUDY FOR THE SOUTHEAST GEORGIA ZONES WELL AFTER MIDNIGHT.
TEMPERATURES WILL FALL QUICKLY AFTER SUNSET AS WINDS DECOUPLE. THE
GRADIENT IS FORECAST TO TIGHTEN A BIT OVERNIGHT AS IDA MOVES NORTH
INTO THE GULF OF MEXICO AND HIGH PRESSURE HOLDS FIRM WELL OFFSHORE.
THIS MAY BE ENOUGH TO SUPPORT A RECOUPLING OF THE BOUNDARY LAYER
ALONG THE COAST AND SOUTH OF INTERSTATE 16 LATER THIS EVENING.
THIS COMBINED WITH A PERSISTENT ONSHORE FLOW AND INCREASING CIRRUS
ALOFT SHOULD HELP MODERATE OVERNIGHT TEMPERATURES SOMEWHAT...EXCEPT
WELL INLAND WHERE COMPLETE DECOUPLING WILL LIKELY PERSIST THROUGH
SUNRISE MONDAY. WILL SEE A LARGE TEMPERATURE GRADIENT ACROSS THE
FORECAST AREA AS A RESULT WITH LOWS RANGING FROM THE UPPER 40S
WELL INLAND TO THE MID 60S ALONG THE BEACH FRONT.
&&
.SHORT TERM /MONDAY/...
THE UPPER RIDGE ACROSS THE SOUTHEAST U.S. WILL BEGIN TO RAPIDLY
BREAKDOWN AND PROPAGATE EAST MONDAY AFTERNOON AS POTENT SHORTWAVE
ENERGY DIGS ACROSS TEXAS AND THE WESTERN GULF OF MEXICO. THE
INCREASING SOUTHERLY FLOW BETWEEN THE UPPER RIDGE AND THE
APPROACHING SHORTWAVE WILL HELP DRIVE HURRICANE IDA NORTHWARD
TOWARDS ACROSS OPEN GULF TOWARDS THE NORTH-CENTRAL GULF COAST. WITH
DIMINISHING SUBSIDENCE ALOFT...THE INCREASING ONSHORE FLOW AND
RESULTING MOISTURE FLUX MAY HELP SUPPORT SOME ISOLATED SHOWER
ACTIVITY OVER THE ATLANTIC WATERS...SOME OF WHICH MAY MAKE A RUN FOR
THE UPPER GEORGIA AND LOWER SOUTH CAROLINA COASTS. BOTH THE NAM AND
SREF SUGGEST THERE IS ENOUGH OF A POTENTIAL FOR SPOTTY MEASURABLE
RAINFALL TO OCCUR MONDAY AFTERNOON...ALBEIT LIGHT...TO JUSTIFY
SLIGHT CHANCE POPS FOR ALL COASTAL ZONES WITH THE EXCEPTION OF
CHARLESTON COUNTY. DRY CONDITIONS SHOULD PREVAIL ELSEWHERE.
INCREASING MID-HIGH LEVEL CLOUD COVER WILL HELP TO LIMIT HIGHS TO
THE 75-77 DEGREE RANGE WITH COOLER CONDITIONS ALONG THE IMMEDIATE
COAST WHERE TEMPERATURES MAY STRUGGLE TO REACH THE UPPER
60S...SIMILAR TO THE PAST SEVERAL DAYS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODEL GUIDANCE IS IN POOR AGREEMENT THROUGH THE EXTENDED PERIODS
THIS AFTERNOON...WITH NO SOLUTION DISPLAYING VERY GOOD RUN TO RUN
CONTINUITY AS THEY STRUGGLE TO GET A HANDLE ON THE EVENTUAL
EVOLUTION OF HURRICANE IDA. AS A RESULT...FORECAST CONFIDENCE IS
WELL BELOW NORMAL THROUGHOUT THE EXTENDED PERIOD.
HURRICANE IDA IS FORECAST TO LIFT NORTHWARD THROUGH THE GULF OF
MEXICO AND MAKE LANDFALL ALONG THE NORTHERN GULF COAST TUESDAY
MORNING...THEN SHIFT EASTWARD ALONG THE GEORGIA/FLORIDA BORDER AND
INTO THE ATLANTIC BY THURSDAY MORNING. THE ECMWF SEEMS TO HAVE THE
BEST HANDLE ON THE FORECAST TRACK PROVIDED BY THE HURRICANE
CENTER...AND SEEMS TO BE A GOOD COMPROMISE BETWEEN ALL OF THE OTHER
OPERATIONAL MODEL SOLUTIONS AND WILL BE FOLLOWED CLOSELY THROUGHOUT
THE EXTENDED PERIODS.
AS FOR FORECAST DETAILS...DEEP MOISTURE WILL BEGIN TO INCREASE IN
ADVANCE OF THE TROPICAL CYCLONE MONDAY NIGHT AS LOW LEVEL FLOW
BECOMES MORE ONSHORE. DEEPEST MOISTURE ALONG WITH BEST ISENTROPIC
ASCENT WILL REMAIN WEST OF THE FORECAST AREA THROUGH THE NIGHT...SO
WILL HOLD POPS IN THE CHANCE RANGE FOR NOW. DEEP MOISTURE AND
DYNAMIC FORCING FROM THE PHASING OF AN UPPER LEVEL LOW AND TROPICAL
CYCLONE WILL OVERSPREAD THE AREA TUESDAY THROUGH WEDNESDAY AS THE
REMNANTS OF IDA PASS BY TO THE SOUTH ALONG THE GEORGIA FLORIDA
BORDER...AND WILL CARRY LIKELY OR HIGH CHANCE POPS ALL AREAS TUESDAY
THROUGH WEDNESDAY.
GUIDANCE SOLUTIONS DEVIATE SIGNIFICANTLY WEDNESDAY NIGHT THROUGH THE
UPCOMING WEEKEND...OFFERING UP A NUMBER OF POSSIBILITIES TO HOW THE
PATTERN WILL EVOLVE. SEVERAL SOLUTIONS NOW DEPICT THE REMNANTS OF
IDA DEVELOPING INTO A FAIRLY STRONG WESTERN ATLANTIC LOW FOR THE
LATE WEEK TIME FRAME...WITH THE GFS SHOWING HIGH PRESSURE SETTLING
SOUTHWARD AND BEING THE DOMINANT WEATHER INFLUENCE ON THE FORECAST
AREA. TO TRY AND MINIMIZE ERROR...HAVE FOLLOWED THE ECMWF SOLUTION
WHICH APPEARS TO BE A GOOD MIDDLE OF THE ROAD COMPROMISE BETWEEN THE
VARIOUS OPERATIONAL MODELS. THIS RESULTS IN THE DEVELOPMENT OF A
WESTERN ATLANTIC LOW OFF THE FLORIDA COAST FOR THE LATE WEEK TIME
FRAME WITH HIGH PRESSURE BUILDING NORTH OF THE REGION. AS FOR
FORECAST DETAILS...WILL CARRY SLIGHT CHANCE POPS WEDNESDAY NIGHT TO
ACCOUNT FOR THE MODELS TRENDING SLOWER WITH THE EXIT OF DEEP
MOISTURE DUE TO THE DEVELOPMENT OF A WESTERN ATLANTIC LOW. HAVE THEN
KEPT THE FORECAST RAIN FREE THURSDAY THROUGH SUNDAY...BUT MUCH OF
THIS WILL DEPEND ON THE POSITIONING OF HIGH PRESSURE TO THE NORTH AS
WELL AS THE LOCATION OF THE WESTERN ATLANTIC LOW IF INDEED IT DOES
END UP DEVELOPING.
COASTAL IMPACTS...
SIGNIFICANT BEACH EROSION...INCREASING TIDES...STRONG WINDS AND HIGH
SURF MAY IMPACT THE COASTAL COUNTIES BY MID WEEK...DEPENDING ON THE
EVENTUAL TRACK IDA/S REMNANTS TAKE. HIGH SURF ADVISORIES...WIND
ADVISORIES AND/OR COASTAL FLOOD ADVISORIES MAY EVENTUALLY BE NEEDED.
RESIDENTS OF SOUTHEAST SOUTH CAROLINA AND SOUTHEAST GEORGIA SHOULD
CONTINUE TO MONITOR NWS FORECASTS AND STATEMENTS THIS WEEK AS A
VARIETY OF HAZARDS COULD IMPACT THE REGION.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE 18Z TAF PERIOD
FOR KCHS AND KSAV. ALTHOUGH MOST AREAS WILL REMAIN CLEAR THIS
AFTERNOON...EXPECT A FEW CUMULUS TO DEVELOP AS AN ONSHORE FLOW
PERSISTS...ESPECIALLY ACROSS KSAV. WILL MAINTAIN FEW TO SCATTERED
STRATUS OVERNIGHT AS LOW LEVEL MOISTURE CONTINUES TO PUSH ONSHORE.
BUT WITH A TIGHTENING GRADIENT...DON/T EXPECT WINDS TO GO CALM
OVERNIGHT. THIS SHOULD HINDER FOG/LOW CEILING DEVELOPMENT. HIGH
CLOUDS WILL INCREASE OVERNIGHT AND INTO SUNDAY AS LOW PRESSURE
OVER THE GULF MOVES TOWARD THE AREA.
EXTENDED AVIATION OUTLOOK....VFR CONDITIONS WILL PREVAIL THROUGH
MONDAY. POTENTIAL FOR MVFR OR IFR CONDITIONS MONDAY NIGHT THROUGH
THURSDAY. LLWS ALSO POSSIBLE WED MORNING. VFR CONDITIONS ARE THEN
EXPECTED THURSDAY NIGHT AND FRIDAY.
&&
.MARINE...
BOTH WINDS AND SEAS HAVE BEEN STEADILY INCREASING ALONG THE
FLORIDA EAST COAST THIS AFTERNOON AS THE GRADIENT BETWEEN
HURRICANE IDA AND HIGH PRESSURE TO THE NORTH TIGHTENS. SHOULD SEE
SIMILAR TRENDS SPREAD ACROSS THE GEORGIA WATERS OVERNIGHT AS THE
GRADIENT THIS FAR NORTH BEGINS TO RESPOND TO IDA/S CONTINUED
NORTHWARD MOVEMENT. THE HIGHEST WINDS LOOK TO REMAIN OVER THE
GEORGIA OFFSHORE WATERS WERE WINDS WILL INCREASE TO 15-20 KT WHILE
10-15 KT SHOULD PREVAIL OVER THE NEARSHORE WATERS. ITS BEEN
DIFFICULT TO DETERMINE SEAS THIS AFTERNOON WITH THE LACK OF BUOY
AND PILOT BOAT OBSERVATIONS ACROSS THE LOCAL MARINE AREA. SEAS AT
41008 HAVE BEEN HOLDING AROUND 4 FT SINCE LATE MORNING WHICH IS A
LITTLE AHEAD OF THE LATEST WW4 OUTPUT. PLAN TO STAY ABOUT 0.5 TO 1
FT AHEAD OF WW4 GUIDANCE FOR TONIGHT WHICH WOULD PLACE 4-6 FT SEAS
IN THE GEORGIA OFFSHORE WATERS BY MID EVENING...BUILDING TO 5-7 FT
LATE. THE CURRENT SMALL CRAFT ADVISORY THERE LOOKS ON TRACK. SEAS
WILL BUILD TO 3-4 FT OVER THE SOUTH CAROLINA NEARSHORE WATERS AND
4-5 FT OVER THE GEORGIA NEARSHORE WATERS.
MARINE CONDITIONS WILL CONTINUE TO SLOWLY DETERIORATE MONDAY AS
COMBINED SEAS INCREASE IN RESPONSE TO THE STRENGTHENING FLOW
BETWEEN IDA AND HIGH PRESSURE TO THE NORTH. SEAS ARE EXPECTED TO
REACH 6 FT ACROSS THE NEARSHORE WATERS SOUTH OF EDISTO BEACH BY
EARLY TO MID AFTERNOON MONDAY AND SINCE THIS IS WITHIN THE SECOND
PERIOD SMALL CRAFT FLAGS WILL BE HOISTED FOR AMZ352-354. LOOKS
LIKE SEAS WILL REMAIN 4-5 FT FOR THE CHARLESTON COUNTY WATERS
NORTH OF EDISTO BEACH WITH SMALL CRAFT ADVISORY CONDITIONS LIKELY
HOLDING OFF UNTIL MONDAY NIGHT. SEAS WILL CONTINUE TO BUILD TO 6-8
FT OVER THE GEORGIA OFFSHORE LEG...CREATING VERY HAZARDOUS
CONDITIONS.
MONDAY NIGHT THROUGH FRIDAY...HURRICANE IDA IS FORECAST TO LIFT
NORTHWARD THROUGH THE GULF OF MEXICO AND MAKE LANDFALL ALONG THE
NORTHERN GULF COAST TUESDAY MORNING. THE SYSTEM IS THEN EXPECTED
TO WEAKEN AS IT TRACKS ALONG THE GEORGIA/FLORIDA BORDER AND INTO
THE WESTERN ATLANTIC BY THURSDAY MORNING. AS STRONG PRESSURE
GRADIENT IS EXPECTED TO RESULT ACROSS THE COASTAL WATERS THROUGH
THE FORECAST PERIOD AS HIGH PRESSURE BUILDS NORTH OF THE REGION
AND THE REMNANTS OF IDA SLIDE BY TO THE SOUTH. SMALL CRAFT
CONDITIONS ARE EXPECTED ACROSS ALL WATERS MONDAY NIGHT THROUGH
THURSDAY...WITH PORTIONS OF THE WATERS POSSIBLY SEEING SMALL CRAFT
CONDITIONS THROUGH FRIDAY. SMALL CRAFT CONDITIONS ARE EXPECTED IN
CHARLESTON HARBOR WEDNESDAY AFTERNOON THROUGH THURSDAY.
DEPENDING ON HOW STRONG THE GRADIENT ENDS UP BECOMING...THERE
REMAINS THE POTENTIAL FOR GALE FORCE CONDITIONS TO IMPACT PORTIONS
OF THE WATERS WEDNESDAY THROUGH THURSDAY EVENING. GALE WATCHES AND
WARNINGS MAY EVENTUALLY BE NEEDED.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM NOON MONDAY TO 5 AM EST FRIDAY
FOR AMZ352.
SMALL CRAFT ADVISORY FROM 9 PM THIS EVENING TO 7 AM EST
SATURDAY FOR AMZ374.
SMALL CRAFT ADVISORY FROM 5 PM MONDAY TO NOON EST FRIDAY FOR
AMZ350.
SMALL CRAFT ADVISORY FROM NOON MONDAY TO 5 PM EST THURSDAY FOR
AMZ354.
&&
$$
000
FXUS62 KCHS 082105
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
405 PM EST SUN NOV 8 2009
...THE REMNANTS OF HURRICANE IDA WILL BRING UNSETTLED CONDITIONS
AND A VARIETY OF HAZARDS TO THE REGION THIS WEEK...
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH
MONDAY AS HURRICANE IDA MOVES NORTH INTO THE GULF OF MEXICO.
IDA IS FORECAST TO MAKE LANDFALL ALONG THE NORTHERN GULF COAST
TUESDAY. IDA/S REMNANT LOW WILL MOVE EAST WEDNESDAY AND EMERGE
OFF THE NORTHEAST FLORIDA COAST THURSDAY RESULTING IN UNSETTLED
CONDITIONS ACROSS THE REGION. HIGH PRESSURE WILL THEN BUILD BACK
INTO THE REGION BY FRIDAY AND REMAIN THE DOMINANT WEATHER FEATURE
THROUGH THE UPCOMING WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
RELATIVELY QUIET AND DRY WEATHER WILL PERSIST INTO TONIGHT AS HIGH
PRESSURE BOTH AT THE SURFACE AND ALOFT HOLDS ITS INFLUENCE OVER
THE REGION. THE SHALLOW CUMULUS FIELD WHICH HAS DEVELOPED OVER
PARTS OF INTERIOR SOUTHEAST GEORGIA WILL QUICKLY DISSIPATE OVER
THE NEXT 1-2 HOURS AS HEATING WANES WITH THE APPROACH OF SUNSET.
VISIBLE SATELLITE IMAGES SHOW EXTENSIVE CLOSED CELL STRATOCUMULUS
LURKING OVER MUCH OF THE OFFSHORE WATERS ALONG THE WESTERN WALL
OF THE GULF STREAM. MODELS SUGGEST MOST OF THE STRATOCUMULUS WILL
REMAIN OFFSHORE TONIGHT AS THE CELLS PROPAGATE OVER THE RELATIVELY
COOLER NEARSHORE WATERS...HOWEVER WE CAN NOT COMPLETELY RULE OUT A
FEW PATCHES MOVING ONSHORE AFTER MIDNIGHT AS THE ONSHORE FLOW
DEEPENS--MAINLY FROM HILTON HEAD SOUTH TO TYBEE ISLAND AND SAPELO
ISLAND. CIRRUS BLOW OFF FROM HURRICANE IDA WILL ALSO BE ON THE
INCREASE LATE...MAINLY ACROSS SOUTHEAST GEORGIA. PLAN TO KEEP
SKIES CLEAR TO MOSTLY CLEAR THIS EVENING...BECOMING PARTLY CLOUDY
FOR THE SOUTHEAST GEORGIA ZONES WELL AFTER MIDNIGHT.
TEMPERATURES WILL FALL QUICKLY AFTER SUNSET AS WINDS DECOUPLE. THE
GRADIENT IS FORECAST TO TIGHTEN A BIT OVERNIGHT AS IDA MOVES NORTH
INTO THE GULF OF MEXICO AND HIGH PRESSURE HOLDS FIRM WELL OFFSHORE.
THIS MAY BE ENOUGH TO SUPPORT A RECOUPLING OF THE BOUNDARY LAYER
ALONG THE COAST AND SOUTH OF INTERSTATE 16 LATER THIS EVENING.
THIS COMBINED WITH A PERSISTENT ONSHORE FLOW AND INCREASING CIRRUS
ALOFT SHOULD HELP MODERATE OVERNIGHT TEMPERATURES SOMEWHAT...EXCEPT
WELL INLAND WHERE COMPLETE DECOUPLING WILL LIKELY PERSIST THROUGH
SUNRISE MONDAY. WILL SEE A LARGE TEMPERATURE GRADIENT ACROSS THE
FORECAST AREA AS A RESULT WITH LOWS RANGING FROM THE UPPER 40S
WELL INLAND TO THE MID 60S ALONG THE BEACH FRONT.
&&
.SHORT TERM /MONDAY/...
THE UPPER RIDGE ACROSS THE SOUTHEAST U.S. WILL BEGIN TO RAPIDLY
BREAKDOWN AND PROPAGATE EAST MONDAY AFTERNOON AS POTENT SHORTWAVE
ENERGY DIGS ACROSS TEXAS AND THE EASTERN GULF OF MEXICO. THE
INCREASING SOUTHERLY FLOW BETWEEN THE UPPER RIDGE AND THE
APPROACHING SHORTWAVE WILL HELP DRIVE HURRICANE IDA NORTHWARD
TOWARDS ACROSS OPEN GULF TOWARDS THE NORTH-CENTRAL GULF COAST.
WITH DIMINISHING SUBSIDENCE ALOFT...THE INCREASING ONSHORE FLOW
AND RESULTING MOISTURE FLUX MAY HELP SUPPORT SOME ISOLATED SHOWER
ACTIVITY OVER THE ATLANTIC WATERS...SOME OF WHICH MAY MAKE A RUN
FOR THE UPPER GEORGIA AND LOWER SOUTH CAROLINA COASTS. BOTH THE
NAM AND SREF SUGGEST THERE IS ENOUGH OF A POTENTIAL FOR SPOTTY
MEASURABLE RAINFALL TO OCCUR MONDAY AFTERNOON...ALBEIT LIGHT...TO
JUSTIFY SLIGHT CHANCE POPS FOR ALL COASTAL ZONES WITH THE
EXCEPTION OF CHARLESTON COUNTY. DRY CONDITIONS SHOULD PREVAIL
ELSEWHERE. INCREASING MID-HIGH LEVEL CLOUD COVER WILL HELP TO
LIMIT HIGHS TO THE 75-77 DEGREE RANGE WITH COOLER CONDITIONS ALONG
THE IMMEDIATE COAST WHERE TEMPERATURES MAY STRUGGLE TO REACH THE
UPPER 60S...SIMILAR TO THE PAST SEVERAL DAYS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
MODEL GUIDANCE IS IN POOR AGREEMENT THROUGH THE EXTENDED PERIODS
THIS AFTERNOON...WITH NO SOLUTION DISPLAYING VERY GOOD RUN TO RUN
CONTINUITY AS THEY STRUGGLE TO GET A HANDLE ON THE EVENTUAL
EVOLUTION OF HURRICANE IDA. AS A RESULT...FORECAST CONFIDENCE IS
WELL BELOW NORMAL THROUGHOUT THE EXTENDED PERIOD.
HURRICANE IDA IS FORECAST TO LIFT NORTHWARD THROUGH THE GULF OF
MEXICO AND MAKE LANDFALL ALONG THE NORTHERN GULF COAST TUESDAY
MORNING...THEN SHIFT EASTWARD ALONG THE GEORGIA/FLORIDA BORDER AND
INTO THE ATLANTIC BY THURSDAY MORNING. THE ECMWF SEEMS TO HAVE THE
BEST HANDLE ON THE FORECAST TRACK PROVIDED BY THE HURRICANE
CENTER...AND SEEMS TO BE A GOOD COMPROMISE BETWEEN ALL OF THE OTHER
OPERATIONAL MODEL SOLUTIONS AND WILL BE FOLLOWED CLOSELY THROUGHOUT
THE EXTENDED PERIODS.
AS FOR FORECAST DETAILS...DEEP MOISTURE WILL BEGIN TO INCREASE IN
ADVANCE OF THE TROPICAL CYCLONE MONDAY NIGHT AS LOW LEVEL FLOW
BECOMES MORE ONSHORE. DEEPEST MOISTURE ALONG WITH BEST ISENTROPIC
ASCENT WILL REMAIN WEST OF THE FORECAST AREA THROUGH THE NIGHT...SO
WILL HOLD POPS IN THE CHANCE RANGE FOR NOW. DEEP MOISTURE AND
DYNAMIC FORCING FROM THE PHASING OF AN UPPER LEVEL LOW AND TROPICAL
CYCLONE WILL OVERSPREAD THE AREA TUESDAY THROUGH WEDNESDAY AS THE
REMNANTS OF IDA PASS BY TO THE SOUTH ALONG THE GEORGIA FLORIDA
BORDER...AND WILL CARRY LIKELY OR HIGH CHANCE POPS ALL AREAS TUESDAY
THROUGH WEDNESDAY.
GUIDANCE SOLUTIONS DEVIATE SIGNIFICANTLY WEDNESDAY NIGHT THROUGH THE
UPCOMING WEEKEND...OFFERING UP A NUMBER OF POSSIBILITIES TO HOW THE
PATTERN WILL EVOLVE. SEVERAL SOLUTIONS NOW DEPICT THE REMNANTS OF
IDA DEVELOPING INTO A FAIRLY STRONG WESTERN ATLANTIC LOW FOR THE LATE
WEEK TIME FRAME...WITH THE GFS SHOWING HIGH PRESSURE SETTLING
SOUTHWARD AND BEING THE DOMINANT WEATHER INFLUENCE ON THE FORECAST
AREA. TO TRY AND MINIMIZE ERROR...HAVE FOLLOWED THE ECMWF SOLUTION
WHICH APPEARS TO BE A GOOD MIDDLE OF THE ROAD COMPROMISE BETWEEN THE
VARIOUS OPERATIONAL MODELS. THIS RESULTS IN THE DEVELOPMENT OF A
WESTERN ATLANTIC LOW OFF THE FLORIDA COAST FOR THE LATE WEEK TIME
FRAME WITH HIGH PRESSURE BUILDING NORTH OF THE REGION. AS FOR
FORECAST DETAILS...WILL CARRY SLIGHT CHANCE POPS WEDNESDAY NIGHT TO
ACCOUNT FOR THE MODELS TRENDING SLOWER WITH THE EXIT OF DEEP
MOISTURE DUE TO THE DEVELOPMENT OF A WESTERN ATLANTIC LOW. HAVE THEN
KEPT THE FORECAST RAIN FREE THURSDAY THROUGH SUNDAY...BUT MUCH OF
THIS WILL DEPEND ON THE POSITIONING OF HIGH PRESSURE TO THE NORTH AS
WELL AS THE LOCATION OF THE WESTERN ATLANTIC LOW IF INDEED IT DOES
END UP DEVELOPING.
COASTAL IMPACTS...SIGNIFICANT BEACH EROSION...INCREASING TIDES...
STRONG WINDS AND HIGH SURF MAY IMPACT THE COASTAL COUNTIES BY MID
WEEK...DEPENDING ON THE EVENTUAL TRACK IDA/S REMNANTS TAKE. HIGH
SURF ADVISORIES...WIND ADVISORIES AND/OR COASTAL FLOOD ADVISORIES
MAY EVENTUALLY BE NEEDED. RESIDENTS OF SOUTHEAST SOUTH CAROLINA
AND SOUTHEAST GEORGIA SHOULD CONTINUE TO MONITOR NWS FORECASTS AND
STATEMENTS THIS WEEK AS A VARIETY OF HAZARDS COULD IMPACT THE
REGION.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE 18Z TAF PERIOD
FOR KCHS AND KSAV. ALTHOUGH MOST AREAS WILL REMAIN CLEAR THIS
AFTERNOON...EXPECT A FEW CUMULUS TO DEVELOP AS AN ONSHORE FLOW
PERSISTS...ESPECIALLY ACROSS KSAV. WILL MAINTAIN FEW TO SCATTERED
STRATUS OVERNIGHT AS LOW LEVEL MOISTURE CONTINUES TO PUSH ONSHORE.
BUT WITH A TIGHTENING GRADIENT...DON/T EXPECT WINDS TO GO CALM
OVERNIGHT. THIS SHOULD HINDER FOG/LOW CEILING DEVELOPMENT. HIGH
CLOUDS WILL INCREASE OVERNIGHT AND INTO SUNDAY AS LOW PRESSURE
OVER THE GULF MOVES TOWARD THE AREA.
EXTENDED AVIATION OUTLOOK....VFR CONDITIONS WILL PREVAIL THROUGH
MONDAY. POTENTIAL FOR MVFR OR IFR CONDITIONS MONDAY NIGHT THROUGH
THURSDAY. LLWS ALSO POSSIBLE WED MORNING. VFR CONDITIONS ARE THEN
EXPECTED THURSDAY NIGHT AND FRIDAY.
&&
.MARINE...
BOTH WINDS AND SEAS HAVE BEEN STEADILY INCREASING ALONG THE
FLORIDA EAST COAST THIS AFTERNOON AS THE GRADIENT BETWEEN
HURRICANE IDA AND HIGH PRESSURE TO THE NORTH TIGHTENS. SHOULD SEE
SIMILAR TRENDS SPREAD ACROSS THE GEORGIA WATERS OVERNIGHT AS THE
GRADIENT THIS FAR NORTH BEGINS TO RESPOND TO IDA/S CONTINUED
NORTHWARD MOVEMENT. THE HIGHEST WINDS LOOK TO REMAIN OVER THE
GEORGIA OFFSHORE WATERS WERE WINDS WILL INCREASE TO 15-20 KT WHILE
10-15 KT SHOULD PREVAIL OVER THE NEARSHORE WATERS. ITS BEEN
DIFFICULT TO DETERMINE SEAS THIS AFTERNOON WITH THE LACK OF BUOY
AND PILOT BOAT OBSERVATIONS ACROSS THE LOCAL MARINE AREA. SEAS AT
41008 HAVE BEEN HOLDING AROUND 4 FT SINCE LATE MORNING WHICH IS A
LITTLE AHEAD OF THE LATEST WW4 OUTPUT. PLAN TO STAY ABOUT 0.5 TO 1
FT AHEAD OF WW4 GUIDANCE FOR TONIGHT WHICH WOULD PLACE 4-6 FT SEAS
IN THE GEORGIA OFFSHORE WATERS BY MID EVENING...BUILDING TO 5-7 FT
LATE. THE CURRENT SMALL CRAFT ADVISORY THERE LOOKS ON TRACK. SEAS
WILL BUILD TO 3-4 FT OVER THE SOUTH CAROLINA NEARSHORE WATERS AND
4-5 FT OVER THE GEORGIA NEARSHORE WATERS.
MARINE CONDITIONS WILL CONTINUE TO SLOWLY DETERIORATE MONDAY AS
COMBINED SEAS INCREASE IN RESPONSE TO THE STRENGTHENING FLOW
BETWEEN IDA AND HIGH PRESSURE TO THE NORTH. SEAS ARE EXPECTED TO
REACH 6 FT ACROSS THE NEARSHORE WATERS SOUTH OF EDISTO BEACH BY
EARLY TO MID AFTERNOON MONDAY AND SINCE THIS IS WITHIN THE SECOND
PERIOD SMALL CRAFT FLAGS WILL BE HOISTED FOR AMZ352-354. LOOKS
LIKE SEAS WILL REMAIN 4-5 FT FOR THE CHARLESTON COUNTY WATERS
NORTH OF EDISTO BEACH WITH SMALL CRAFT ADVISORY CONDITIONS LIKELY
HOLDING OFF UNTIL MONDAY NIGHT. SEAS WILL CONTINUE TO BUILD TO 6-8
FT OVER THE GEORGIA OFFSHORE LEG...CREATING VERY HAZARDOUS
CONDITIONS.
MONDAY NIGHT THROUGH FRIDAY...HURRICANE IDA IS FORECAST TO LIFT
NORTHWARD THROUGH THE GULF OF MEXICO AND MAKE LANDFALL ALONG THE
NORTHERN GULF COAST TUESDAY MORNING. THE SYSTEM IS THEN EXPECTED
TO WEAKEN AS IT TRACKS ALONG THE GEORGIA/FLORIDA BORDER AND INTO
THE WESTERN ATLANTIC BY THURSDAY MORNING. AS STRONG PRESSURE
GRADIENT IS EXPECTED TO RESULT ACROSS THE COASTAL WATERS THROUGH
THE FORECAST PERIOD AS HIGH PRESSURE BUILDS NORTH OF THE REGION
AND THE REMNANTS OF IDA SLIDE BY TO THE SOUTH. SMALL CRAFT
CONDITIONS ARE EXPECTED ACROSS ALL WATERS MONDAY NIGHT THROUGH
THURSDAY...WITH PORTIONS OF THE WATERS POSSIBLY SEEING SMALL CRAFT
CONDITIONS THROUGH FRIDAY. SMALL CRAFT CONDITIONS ARE EXPECTED IN
CHARLESTON HARBOR WEDNESDAY AFTERNOON THROUGH THURSDAY.
DEPENDING ON HOW STRONG THE GRADIENT ENDS UP BECOMING...THERE
REMAINS THE POTENTIAL FOR GALE FORCE CONDITIONS TO IMPACT PORTIONS
OF THE WATERS WEDNESDAY THROUGH THURSDAY EVENING. GALE WATCHES AND
WARNINGS MAY EVENTUALLY BE NEEDED.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM NOON MONDAY TO 5 AM EST FRIDAY FOR
AMZ352.
SMALL CRAFT ADVISORY FROM 9 PM THIS EVENING TO 7 AM EST
SATURDAY FOR AMZ374.
SMALL CRAFT ADVISORY FROM 5 PM MONDAY TO NOON EST FRIDAY FOR
AMZ350.
SMALL CRAFT ADVISORY FROM NOON MONDAY TO 5 PM EST THURSDAY FOR
AMZ354.
&&
$$
000
FXUS62 KGSP 081935
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
235 PM EST SUN NOV 8 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH TOMORROW.
ABUNDANT MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS THEN
EXPECTED TO MOVE OVER THE CAROLINAS AND NORTH GEORGIA AHEAD OF A
COLD FRONT ON TUESDAY. THE FRONT IS EXPECTED TO CROSS THE AREA LATE
TUESDAY INTO EARLY WEDNESDAY. HIGH PRESSURE WILL THEN RETURN FOR THE
LATER PART OF THE WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
UPPER RIDGE AXIS SLIDES EAST OF THE AREA TONIGHT PRODUCING SLY FLOW
AS SHORT WAVES APPROACH FROM THE WEST. AT THE SFC...THE CENTER OF
HIGH PRESSURE MOVES EAST BUT RIDGING REMAINS OVER THE AREA KEEPING
WINDS LIGHT. CIRRUS WILL SLOWLY INCREASE OVER THE AREA BUT REMAIN
THIN. LOWS END UP NEAR NORMAL MOST LOCATIONS...BUT ABOVE NORMAL IN
THE THERMAL BELT AREAS OF THE UPSTATE.
THERE IS SOME EASTWARD MOVEMENT OF THE UPPER FEATURES MONDAY...BUT
BEST ENERGY REMAINS TO OUR WEST. SFC HIGH PRESSURE RIDGE WEAKENS BUT
REMAINS CENTERED OVER NC. THIS ALLOWS A SLIGHT GRADIENT INCREASE AS
THE TROPICAL APPROACHES FROM THE SOUTH...BUT WINDS REMAIN GENERALLY
LIGHT. INCREASE IN CLOUDS LATE IN THE DAY FROM THE WEST AND SLIGHTLY
LOWER THICKNESSES WILL LEAD TO A COOLING TREND FOR HIGHS. HOWEVER...
THEY WILL STILL BE AS MUCH AS 10 DEGREES ABOVE NORMAL.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 230 PM EDT SUNDAY...THE MODELS BRING A SOUTHERN STREAM SHORTWAVE
EAST ACROSS THE LOWER MS RIVER VALLEY MONDAY NIGHT...WITH THE GFS
REACHING THE AL/MS BORDER TUE MORNING...WHILE THE NAM IS BACK IN
SOUTHERN ARKANSAS. BY TUE EVENING THE GFS SHORTWAVE IS IN EAST TN WHILE
THE NAM IS BACK IN WEST TN. TO COMPLICATE THINGS FURTHER...MOISTURE
ASSOCIATED WITH TROPICAL SYSTEM IDA IS EXPECTED TO BE DRAWN NORTH INTO
THE GULF STATES MONDAY NIGHT. SLIGHT CHANCE POPS WILL BE CARRIED MONDAY
EVENING...WITH POPS INCREASING TO LIKELY IN NORTHEAST GA AND CHANCE
ELSEWHERE OVERNIGHT. THE GFS FASTER TO SPREAD DEEP MOISTURE...
ISENTROPIC UPGLIDE...AND UPSLOPE FLOW INTO THE SOUTHEAST FACING BLUE
RIDGE ESCARPMENT OF NORTHEAST GA AND UPSTATE SC ON TUE...BUT EITHER WAY
IT LOOKS LIKE A WET DAY...AND CATEGORICAL POPS WILL BE CARRIED IN THE
SOUTHWEST PORTION OF THE AREA...TRENDING DOWNWARD TO LIKELY IN THE
CENTRAL PORTION...AND CHANCE IN THE FAR NORTHEAST.
ALTHOUGH DETAILS OF THE END OF THE EVENT VARY BY MODEL...SOME DRYING
FROM THE SOUTHWEST IS INDICATED WEDNESDAY NIGHT. USING A CONSERVATIVE
APPROACH...LIKELY POPS WILL BE MAINTAINED OVER MOST OF THE AREA...
INCLUDING MUCH OF THE TN BORDER...WHERE UPSLOPE FLOW WILL FOLLOW THE
PASSAGE OF THE SURFACE LOW. SOME DECREASE IN POPS IS POSSIBLE ALONG THE
BLUE RIDGE ESCARPMENT AS FLOW BECOMES DOWNSLOPE.
THE DIURNAL TEMPERATURE RANGE WILL BE LIMITED BY CLOUD COVER AND
MOISTURE...AND AN ATTEMPT WAS MADE TO KEEP FORECAST VALUES WITH THE
SUBSTANTIAL SPREAD OF THE MODEL GUIDANCE. AT THIS POINT THE FORECAST
WILL CARRY UP TO THREE INCHES OF RAINFALL ALONG THE GA/SC BLUE RIDGE
ESCARPMENT...PER HPC GUIDANCE. THIS VALUE COULD EASILY BE HIGHER OR
LOWER DEPENDING ON HOW FACTORS COME TOGETHER....BUT THERE DOES SEEM TO
BE BETTER CONSENSUS BACKING HIGHER NUMBERS...AND HEAVY RAINFALL WILL BE
MENTIONED IN THE HAZARDOUS WEATHER OUTLOOK. ANOTHER POTENTIAL HAZARD
WILL BE WINDS APPROACHING ADVISORY CRITERIA AT HIGHER ELEVATIONS ON
TUESDAY...BUT CONFIDENCE IS LOWER THAN IT IS FOR HEAVY RAINFALL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 200 PM SUNDAY...WITH CONSIDERABLE UNCERTAINTY...A LOW OR
TROUGH WHICH CONTAINS THE REMNANT CIRCULATION AND MOISTURE OF IDA
SHOULD BE IN PLACE SOMEWHERE ALONG THE SE COAST OF THE U.S. WED
NIGHT. THE OPERATIONAL GFS APPEARS TOO DEEP...TOO FAR INLAND...AND
TOO FAR NE WITH THE TRANSITIONING SYSTEM WED NIGHT. WILL THUS SHY
AWAY FROM THE WRAP AROUND MOISTURE AND COLD PROFILES ACROSS NW NC
FOR WED NIGHT...AND LEAN TOWARD THE DRIER SREF/GFS ENSEMBLE MEAN
SOLUTIONS AT THE START OF THE PERIOD. ADDITIONAL DRYING IS EXPECTED
THROUGH THU AS SFC HIGH PRES BUILDS DOWN FROM THE NW.
A BROAD RIDGE OF HIGH PRESSURE WILL THEN MOVE OVER THE FORECAST AREA
FROM THE WEST LATE THU INTO THE WEEKEND. SOME SOUTHERLY RETURN FLOW
MOISTURE WILL GRADUALLY DEVELOP INTO THE SRN APPALACHIANS AROUND THE
SFC HIGH PRES...BUT THIS WOULD WARRANT LITTLE MORE THAN MTN SLIGHT
CHANCE POPS SAT AFTN AND LOW END SLIGHT CHC TO CHC POPS SUNDAY AFTN.
TEMPS WILL BE NEAR NORMAL EARLY IN THE PERIOD...BECOMING SLIGHTLY
ABOVE NORMAL OVER THE WEEKEND.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
AT KCLT AND ELSEWHERE...DRY HIGH PRESSURE WILL REMAIN OVER THE AREA
SLIDES SLOWLY EASTWARD THRU THE PERIOD. LIGHT SLY WINDS BECOME LIGHT
AND VARIABLE TO CALM THIS EVENING. KAVL IS THE EXCEPTION WHERE NLY
WIND BECOMES SELY LATE THIS AFTERNOON...THEN CALM THIS EVENING.
THERE WILL BE SOME PATCHY MVFR/IFR FOG ESPECIALLY NEAR RIVERS AND
LAKES. HOWEVER...GUIDANCE IS MIXED ON DEVELOPMENT AT TAF SITES. WILL
LEAVE OUT FOR NOW. NELY WINDS DEVELOP BY MID MORNING MONDAY AS IDA
OR ITS REMNANTS MOVE NORTH TOWARD THE AREA FROM THE GULF. ONLY A
SLOW INCREASE IN CIRRUS EXPECTED.
OUTLOOK...A COLD FRONT OR REMNANTS OF IDA ARE EXPECTED TO MOVE IN TUE
WITH INCREASING CHC SHWRS AND CIG/VSBY RESTRICTIONS. FRONT SHOULD MOVE
EAST WED WITH VFR RETURNING.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...RWH
SHORT TERM...JAT
LONG TERM...HG
AVIATION...RWH
000
FXUS62 KCAE 081754
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1254 PM EST SUN NOV 8 2009
.SYNOPSIS...
DRY HIGH PRESSURE EXTENDING INTO THE FORECAST AREA WILL CONTINUE TO
DOMINATE THROUGH MONDAY. A COLD FRONT ALONG WITH A SURGE OF TROPICAL
MOISTURE WILL AFFECT THE AREA MAINLY TUESDAY AND TUESDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
DRY HIGH PRESSURE ACROSS THE AREA TONIGHT...ONLY SOME HIGH LEVEL
CLOUDS MAINLY AFTER MIDNIGHT. TEMPERATURES SLIGHTLY WARMER THAN
PREVIOUS NIGHTS ALTHOUGH WITH GOOD RADIATIONAL COOLING PREFER MAV
GUIDANCE.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
LITTLE CHANGE MADE FROM PREVIOUS FORECAST. CONSIDERABLE
UNCERTAINTY NOTED IN THE ENSEMBLE GUIDANCE. THE MODELS AGREE KEEPING
DRY HIGH PRESSURE IN CONTROL THROUGH MONDAY. THE MAIN PROBLEM IS
THE IMPACT OF TROPICAL MOISTURE ASSOCIATED WITH IDA. CONFIDENCE
REMAINS LOW BECAUSE OF LARGE SPREAD IN THE MODELS. UPPER TROUGH
MOVING ACROSS THE SOUTHERN PLAINS WILL MOVE INTO THE GULF COAST
REGION TUESDAY AND POSSIBLY AFFECT MOVEMENT OF IDA. NAM REMAINS
SLOWER MOVING IDA INLAND WITH SREF POPS HIGHER ACROSS
GEORGIA/ALABAMA. GFS APPEARS TO BE AN OUTLIER IN THE MREF. BOTH
GFS/NAM INDICATE INCREASING ISENTROPIC LIFT/MOISTURE FLUX
TUESDAY/TUESDAY NIGHT SO WILL INCREASE POPS SLIGHTLY. COULD BE
HEAVY RAIN ASSOCIATED WITH TROPICAL MOISTURE FLUX. MODELS SHOW
STRONG VERTICAL WIND SHEAR BUT TIMING DIFFERENT. 30 TO 50 KT 850MB
JET POSSIBLE AND ELEVATED INSTABILITY NOTED.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
TROPICAL SYSTEM MAY LINGER IN THE AREA WEDNESDAY...CONSIDERABLE
UNCERTAINTY AT THIS TIME. WILL KEEP LOW CHANCE POPS WITH AREA OF
LOW PRESSURE ALONG COASTAL FRONT AND CLOUDINESS LINGERING IN THE
MIDLANDS THROUGH EARLY AFTERNOON. HIGH PRESSURE IN THE GREAT LAKES
BUILDING SOUTHEAST...SHOULD BE DRY THURSDAY THROUGH WEEKEND WITH
TEMPERATURES NEAR OR SLIGHTLY ABOVE CLIMATOLOGY.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
DRY HIGH PRESSURE ANCHORED OFF THE CAROLINA COAST WILL REMAIN THE
DOMINANT WEATHER FACTOR THROUGH THE TAF PERIOD. MAINLY CLEAR SKIES
THROUGH TONIGHT...WITH SOME MVFR FOG POSSIBLE AT AGS AND OGB. SOME
CIRRUS POSSIBLE AFTER SUNRISE MONDAY MORNING. SFC WINDS LIGHT AND
VARIABLE...BECOMING LIGHT E-SE AFTER 14Z MONDAY.
EXTENDED AVIATION OUTLOOK...STILL SOME UNCERTAINTY CONCERNING THE
FUTURE TRACK OF HURRICANE IDA TUESDAY INTO WEDNESDAY. AT THIS
TIME...THINK THERE WILL BE WIDESPREAD CEILING AND VISIBILITY
RESTRICTIONS ACROSS THE AREA TUESDAY INTO WEDNESDAY ASSOCIATED WITH
ISENTROPIC LIFT.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
000
FXUS62 KGSP 081737
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1237 PM EST SUN NOV 8 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
ABUNDANT MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS THEN
EXPECTED TO MOVE INTO THE CAROLINAS AND NORTH GEORGIA AHEAD OF A
COLD FRONT ON TUESDAY...WITH THE FRONT EXPECTED TO CROSS THE AREA
LATE TUESDAY INTO EARLY WEDNESDAY. HIGH PRESSURE WILL THEN RETURN
FOR THE LATER HALF OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
GOING FCST IN GOOD SHAPE. OTHER THAN SOME SPOTTY THIN CIRRUS OVER
THE WRN CWFA...NEARLY FULL SUNSHINE EXPECTED THIS AFTERNOON.
GENERALLY LIGHT NLY WIND BECOMES LIGHT SLY WIND THIS AFTERNOON.
MORNING OBSERVED THICKNESSES SUPPORT THE FCST HIGHS AROUND 10
DEGREES ABOVE NORMAL.
UPPER RIDGE WILL CONT TO BUILD THIS EVE BEFORE AXIS STARTS TO TRACK
E. THIS WILL ALLOW SHORTWAVE TO APPROACH FROM THE SW AND CLOUDS WILL
BEGIN TO INCREASE AHEAD OF APPROACHING GULF TROPICAL SYSTEM
OVERNIGHT. LOW TEMPS WILL BE ABOVE AVG.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 305 AM SUNDAY...THE FATE OF THE SHORT TERM WEATHER OBVIOUSLY
HINGES UPON THE EVOLUTION OF HURRICANE IDA. ALTHOUGH THERE IS NOT A
GREAT DEAL OF DISAGREEMENT AMONG CONSENSUS MODEL SOLUTIONS AND NHC
GUIDANCE REGARDING THE TRACK OF THE STORM...THERE IS CONSIDERABLE
DISAGREEMENT ON HOW THE STORM WILL INTERACT WITH VARIOUS SYNOPTIC
FEATURES. THE GFS CONTINUES TO BE THE MOST AGGRESSIVE IN ADVECTING A
PLUME OF TROPICAL MOISTURE OVER MUCH OF THE SOUTHEAST TUESDAY AS A
RESULT OF A STRENGTHENING HEIGHT GRADIENT THAT DEVELOPS IN RESPONSE
TO DIGGING NORTHERN STREAM WAVE AND INTENSIFYING SOUTHERN STREAM
ENERGY PHASING WITH THE IDA CIRCULATION. THIS TROPICAL MOISTURE
COMBINES WITH UPSLOPE/ISENTROPIC LIFT TO PRODUCE HEAVY RAINFALL
ACROSS MUCH OF THE CWFA. THE 12Z ECMWF WAS MORE SUPPRESSED WITH THE
NORTHWARD EXTENT OF THE MOISTURE PLUME...DUE TO MUCH WEAKER MID-
LEVEL FLOW...AND THIS WAS REMINISCENT OF THE GFS ENSEMBLE SUITE.
MUCH OF THE FORECAST WAS LEANED ON THIS 12Z ECMWF/GEFS SCENARIO.
HOWEVER...THE 00Z ECMWF IS NOW VERY SIMILAR TO THE GFS SOLUTION...
WHICH IS DISCONCERTING TO SAY THE LEAST.
POPS HAVE BEEN INCREASED AGAIN TO LIKELY ACROSS THE SOUTHERN HALF OF
THE AREA FOR TUESDAY. HOWEVER...WE WILL CONTINUE TO FEATURE VERY
CONSERVATIVE QPF NUMBERS UNTIL MORE CONFIDENCE CAN BE GLEANED FROM
MODEL SOLUTIONS. ANY PRECIPITATION IS EXPECTED TO END RATHER QUICKLY
TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 315 AM SUNDAY...COOL/DRY HIGH PRESSURE IS EXPECTED TO SETTLE
IN BEHIND A COLD FRONT FOR MUCH OF THE MEDIUM RANGE. THIS WIL RESULT
IN A POP-LESS FORECAST WITH TEMPS EXPECTED TO AVERAGE AROUND NORMAL
THROUGH THE PERIOD.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
AT KCLT AND ELSEWHERE...DRY HIGH PRESSURE WILL REMAIN OVER THE AREA
SLIDES SLOWLY EASTWARD THRU THE PERIOD. LIGHT SLY WINDS BECOME LIGHT
AND VARIABLE TO CALM THIS EVENING. KAVL IS THE EXCEPTION WHERE NLY
WIND BECOMES SELY LATE THIS AFTERNOON...THEN CALM THIS EVENING.
THERE WILL BE SOME PATCHY MVFR/IFR FOG ESPECIALLY NEAR RIVERS AND
LAKES. HOWEVER...GUIDANCE IS MIXED ON DEVELOPMENT AT TAF SITES. WILL
LEAVE OUT FOR NOW. NELY WINDS DEVELOP BY MID MORNING MONDAY AS IDA
OR ITS REMNANTS MOVE NORTH TOWARD THE AREA FROM THE GULF. ONLY A
SLOW INCREASE IN CIRRUS EXPECTED.
OUTLOOK...A COLD FRONT OR REMNANTS OF IDA ARE EXPECTED TO MOVE IN TUE
WITH INCREASING CHC SHWRS AND CIG/VSBY RESTRICTIONS. FRONT SHOULD MOVE
EAST WED WITH VFR RETURNING.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...RB/RWH
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...RWH
000
FXUS62 KCHS 081733
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1233 PM EST SUN NOV 8 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH
TONIGHT. HURRICANE IDA WILL LIFT NORTH INTO THE GULF OF MEXICO
TONIGHT AND MONDAY BEFORE LAKING LANDFALL AS A LARGE NON-TROPICAL
LOW ALONG THE NORTHERN GULF COAST TUESDAY MORNING. IDA/S REMNANT
LOW WILL MOVE EAST WEDNESDAY AND EMERGE OFF THE NORTHEAST FLORIDA
COAST THURSDAY RESULTING IN UNSETTLED CONDITIONS OVER THE REGION.
HIGH PRESSURE WILL THEN BUILD BACK INTO THE REGION BY FRIDAY AND
REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE FIRST PART OF NEXT
WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NO SIGNIFICANT CHANGES WERE MADE THE GRIDS THIS MORNING. HIGH
PRESSURE BOTH AT THE SURFACE AND ALOFT WILL REMAIN ANCHORED TO THE
REGION TODAY RESULTING IN A CONTINUATION OF DRY AND SEASONABLE
WEATHER. LOW-LEVEL THICKNESSES GENERALLY SUPPORT HIGHS IN THE MID
70S WITH COOLER TEMPERATURES AT THE COAST WHERE AN ONSHORE FLOW
WILL HELP MODERATE CONDITIONS THERE SOMEWHAT. MEAN LOW-LEVEL
TRAJECTORIES SUGGEST THE BULK OF THE CLOSED CELL CUMULUS OVER THE
WESTERN WALL OF THE GULF STREAM WILL REMAIN EAST AND SOUTH OF THE
FORECAST AREA TODAY...ALTHOUGH SOME IT COULD BRUSH PARTS OF
MCINTOSH COUNTY LATER IN THE AFTERNOON. FORECAST SOUNDINGS SUPPORT
A FEW PATCHES OF SHALLOW CUMULUS DEVELOPING LATER TODAY...MAINLY
SOUTH OF I-16 AND JUST INLAND ALONG THE LOWER SOUTH CAROLINA
COAST...BUT WE REALLY DO NOT EXPECT TOO MUCH IN THE WAY OF CLOUD
COVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
HURRICANE IDA IS FORECAST TO TRACK NORTH ACROSS THE CENTRAL GULF
OF MEXICO BY THE NATIONAL HURRICANE CENTER...WHILE STRONG HIGH
PRESSURE REMAINS IN PLACE NORTH OF THE REGION. THE SURFACE
PRESSURE GRADIENT BETWEEN THESE TWO SYSTEMS WILL BEGIN TO TIGHTEN
OVER THE REGION TONIGHT...PREVENTING WINDS FROM DECOUPLING ACROSS
COASTAL AREAS. CIRRUS SHOULD BEGIN TO INCREASE/THICKEN FROM THE
SOUTH TONIGHT...WHILE THE PERSISTENT LOW LEVEL ONSHORE FLOW COULD
ALLOW SOME STRATOCUMULUS TO ADVECT INLAND LATER IN THE NIGHT. THE
INCREASED CLOUD COVER AND/OR LACK OF DECOUPLED WINDS SHOULD LIMIT
COOLING TONIGHT...KEEPING LOWS IN THE MID TO UPPER 50S TOWARD THE
COAST. AREAS FARTHER INLAND COULD SEE LOWS AROUND 50 OR IN THE
LOWER 50S DUE TO LIGHTER WINDS HOWEVER.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
FAIRLY GOOD MODEL AGREEMENT THIS PERIOD EXCEPT FOR THE EVOLUTION
OF TROPICAL CYCLONE IDA AND ITS REMNANTS FOR EARLY TO MID WEEK.
HIGH PRESSURE TO THE NORTH WILL CONTINUE THROUGH MONDAY BEFORE THE
THE HIGH BEGINS TO BREAK DOWN DUE TO THE APPROACH OF A SURFACE LOW
PRESSURE FROM THE SOUTH /TROPICAL CYCLONE IDA/ AND AN UPPER-LEVEL
TROUGH FROM THE WEST. ALTHOUGH TC IDA WILL BE TRANSITIONING INTO AN
EXTRA-TROPICAL SYSTEM NEAR THE GULF COAST TUESDAY...PLENTY OF DEEP
MOISTURE WILL BE PULLED INTO THE AREA AHEAD OF THE STORM AND THE
UPPER TROUGH. WILL CONTINUE TO CARRY LIKELY RAIN CHANCES
TUESDAY/TUESDAY NIGHT. IMPROVING CONDITIONS ARE THEN EXPECTED
WEDNESDAY AS THE UPPER TROUGH SHIFTS OFFSHORE TAKING THE DEEP
MOISTURE WITH IT. STILL LOOKING AT THE POTENTIAL FOR A FEW INCHES OF
RAIN WITH THIS EVENT BUT WITH THE RECENT DRY WEATHER WE DO NOT
EXPECT ANY FLOODING PROBLEMS AT THIS POINT. THUNDER PROSPECTS APPEAR
TOO LOW TO MENTION AT THIS TIME...BUT THERE IS A CHANCE ON TUE/TUE
NIGHT IF THE WARM SECTOR GETS INTO THE AREA.
TEMPERATURES WILL GENERALLY BE NEAR NORMAL THROUGH THE PERIOD EXCEPT
FOR WELL ABOVE NORMAL TEMPERATURES MONDAY AND SATURDAY.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE 18Z TAF PERIOD
FOR KCHS AND KSAV. ALTHOUGH MOST AREAS WILL REMAIN CLEAR THIS
AFTERNOON...EXPECT A FEW CUMULUS TO DEVELOP AS AN ONSHORE FLOW
PERSISTS...ESPECIALLY ACROSS KSAV. WILL MAINTAIN FEW TO SCATTERED
STRATUS OVERNIGHT AS LOW LEVEL MOISTURE CONTINUES TO PUSH ONSHORE.
BUT WITH A TIGHTENING GRADIENT...DON/T EXPECT WINDS TO GO CALM
OVERNIGHT. THIS SHOULD HINDER FOG/LOW CEILING DEVELOPMENT. HIGH
CLOUDS WILL INCREASE OVERNIGHT AND INTO SUNDAY AS LOW PRESSURE
OVER THE GULF MOVES TOWARD THE AREA.
EXTENDED AVIATION OUTLOOK....VFR CONDITIONS WILL PREVAIL THROUGH
MON. POTENTIAL FOR MVFR OR IFR CONDITIONS MON NIGHT THROUGH WED.
LLWS ALSO POSSIBLE WED MORNING. VFR CONDITIONS EXPECTED WED NIGHT
INTO THU.
&&
.MARINE...
SEAS ARE UP TO 4 FT AT 41008 WHICH IS A LITTLE FASTER THAN
EXPECTED. OPTED TO MOVE THE START TIME OF THE SMALL CRAFT ADVISORY
FOR THE GEORGIA OFFSHORE WATERS UP BY SEVERAL HOURS AS A RESULT.
OTHERWISE E/NE WINDS WILL CONTINUE TODAY WITH SEAS 2-4 FT
NEARSHORE WATERS AND BUILDING TO 4-5 FT OFFSHORE WATERS. LATEST
NHC FORECAST PLACES THE REMNANT LOW OF IDA OFF THE NE FLORIDA
COAST THU MORNING. PER COORD WITH JAX...NO CHANGES WILL BE MADE TO
THURSDAY/S FORECAST BUT SOME CHANGES MAY BE NEEDED FOR THE
AFTERNOON FORECAST PACKAGE.
THE SURFACE PRESSURE GRADIENT BETWEEN HIGH PRESSURE OVER THE
WESTERN ATLANTIC AND HURRICANE IDA MOVING ACROSS THE CENTRAL GULF
OF MEXICO WILL BEGIN TO TIGHTEN OVER THE WATERS TONIGHT. THIS WILL
CAUSE ONSHORE WINDS TO INCREASE TO AS HIGH AS 15 KT OVER THE NEAR
SHORE WATERS AND 15-20 KT OVER THE OUTER GEORGIA WATERS. THE
FAVORABLE FETCH WILL ALLOW SEAS TO BUILD AS WELL...AND A SMALL
CRAFT ADVISORY HAS BEEN ISSUED FOR THE OUTER GEORGIA WATERS
BEGINNING AT MIDNIGHT AS A RESULT.
MONDAY THROUGH THURSDAY...HIGH PRES TO THE N WILL GIVE WAY TO A LOW
PRES SYSTEM APPROACHING FROM THE SW /TC IDA OR ITS REMNANTS/ MON AND
MON NIGHT. MEANWHILE...AN APPROACHING UPPER TROUGH OF LOW PRES LOOKS
TO PICK UP TC IDA /OR PART OF THE SYSTEM/ AND MOVE IT NE OVER/NEAR
THE MARINE AREA TUE/TUE NIGHT. HIGH PRES WILL THEN BUILD IN BEHIND
THE DEPARTING LOW WED/THU. DUE TO THE CONSIDERABLE UNCERTAINTY WITH
THE EVOLUTION OF TC IDA AND ITS REMNANTS...MARINERS ARE REMINDED
THAT THERE IS QUITE A BIT OF FORECAST UNCERTAINTY AT THIS TIME.
ONGOING SCA CONDITIONS ACROSS THE GA WATERS BEYOND 20 NM ARE LIKELY
TO TRANSITION INTO THE COASTAL WATERS WITHIN 20 NM MON NIGHT AS SEAS
BUILD TO 6 FT. A VERY STRONG PRES GRADIENT WILL EVENTUALLY SET UP
B/W THE DEPARTING LOW AND A BUILDING HIGH PRES SYSTEM INLAND TUE
NIGHT/WED. IT IS DURING THIS TIME THAT GALES ARE POSSIBLE...
ESPECIALLY ACROSS THE WATERS BEYOND 20 NM FROM SHORE. IMPROVING
CONDS EXPECTED THU WITH NO HEADLINES EXPECTED WITHIN THE NEARSHORE
WATERS BY THU NIGHT.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 9 PM THIS EVENING TO 10 AM EST
THURSDAY FOR AMZ374.
&&
$$
000
FXUS62 KCAE 081722
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1221 PM EST SUN NOV 8 2009
.SYNOPSIS...
DRY HIGH PRESSURE EXTENDING INTO THE FORECAST AREA WILL CONTINUE TO
DOMINATE THROUGH MONDAY. A COLD FRONT ALONG WITH A SURGE OF TROPICAL
MOISTURE WILL AFFECT THE AREA MAINLY TUESDAY AND TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DRY HIGH PRESSURE RIDGING INTO THE FORECAST AREA WILL CONTINUE TO
DOMINATE TODAY. USED THE COOLER TEMPERATURE GUIDANCE BECAUSE OF
VERIFICATION THE PAST FEW DAYS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
THE MODELS AGREED KEEPING DRY HIGH PRESSURE IN CONTROL TONIGHT
THROUGH MONDAY. THE GFS WAS FASTER MOVING MOISTURE AND SIGNIFICANT
ISENTROPIC LIFT INTO THE FORECAST AREA LATE MONDAY NIGHT COMPARED
TO THE NAM. THE MAV MOS INDICATED CATEGORICAL POPS MONDAY NIGHT. THE
MET MOS WAS MUCH LOWER. KEPT POPS LESS THAN 20 PERCENT THROUGH
MONDAY WITH CHANCE POPS MONDAY NIGHT. THE CHANCE POPS MONDAY NIGHT
WERE AN AVERAGE OF THE MAV AND MET MOS. STRONG RADIATIONAL COOLING
SUPPORTED THE COOLER GUIDANCE TEMPERATURES TONIGHT. USED THE
GUIDANCE CONSENSUS FOR THE REST OF THE TEMPERATURE FORECAST.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE MAIN FORECAST PROBLEM IS THE IMPACT OF TROPICAL MOISTURE
ASSOCIATED WITH IDA. CONFIDENCE IS LOW BECAUSE OF MODEL
INCONSISTENCY. THE GFS SHOWED DEEP MOISTURE AND STRONG ISENTROPIC
LIFT TUESDAY. IT INDICATED H85 WINDS NEAR 45 KNOTS WITH AN
INVERTED SURFACE TROUGH EXTENDING THROUGH THE FORECAST AREA. THIS
SUPPORTED A SEVERE THUNDERSTORM AND FLOOD THREAT. THE NAM WAS
SLOWER AND SHOWED LESS ISENTROPIC LIFT AND DEEPER MOISTURE
SUPPRESSED FARTHER SOUTH. THE 12Z SATURDAY ECMWF WAS CLOSER TO
THE NAM. THE 00Z SUNDAY ECMWF WAS CLOSER TO THE GFS WITH RESPECT
TO SPREADING THE DEEP MOISTURE NORTHWARD...BUT WAS SLOWER. BELIEVE
THE BEST FORECAST FOR NOW IS TO ADJUST POPS UPWARD SLIGHTLY BASED
ON THE ECMWF TREND WITH POPS LIKELY TUESDAY AND TUESDAY NIGHT.
THE MODELS ARE IN GOOD AGREEMENT SHOWING DRY HIGH PRESSURE
DOMINATING THURSDAY THROUGH SATURDAY.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
DRY HIGH PRESSURE ANCHORED OFF THE CAROLINA COAST WILL REMAIN THE
DOMINANT WEATHER FACTOR THROUGH THE TAF PERIOD. MAINLY CLEAR SKIES
THROUGH TONIGHT...WITH SOME MVFR FOG POSSIBLE AT AGS AND OGB. SOME
CIRRUS POSSIBLE AFTER SUNRISE MONDAY MORNING. SFC WINDS LIGHT AND
VARIABLE...BECOMING LIGHT E-SE AFTER 14Z MONDAY.
EXTENDED AVIATION OUTLOOK...STILL SOME UNCERTAINTY CONCERNING THE
FUTURE TRACK OF HURRICANE IDA TUESDAY INTO WEDNESDAY. AT THIS
TIME...THINK THERE WILL BE WIDESPREAD CEILING AND VISIBILITY
RESTRICTIONS ACROSS THE AREA TUESDAY INTO WEDNESDAY ASSOCIATED WITH
ISENTROPIC LIFT.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
000
FXUS62 KGSP 081530
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1030 AM EST SUN NOV 8 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
ABUNDANT MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS THEN
EXPECTED TO MOVE INTO THE CAROLINAS AND NORTH GEORGIA AHEAD OF A
COLD FRONT ON TUESDAY...WITH THE FRONT EXPECTED TO CROSS THE AREA
LATE TUESDAY INTO EARLY WEDNESDAY. HIGH PRESSURE WILL THEN RETURN
FOR THE LATER HALF OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
GOING FCST IN GOOD SHAPE. OTHER THAN SOME SPOTTY THIN CIRRUS OVER
THE WRN CWFA...NEARLY FULL SUNSHINE EXPECTED THIS AFTERNOON.
GENERALLY LIGHT NLY WIND BECOMES LIGHT SLY WIND THIS AFTERNOON.
MORNING OBSERVED THICKNESSES SUPPORT THE FCST HIGHS AROUND 10
DEGREES ABOVE NORMAL.
UPPER RIDGE WILL CONT TO BUILD THIS EVE BEFORE AXIS STARTS TO TRACK
E. THIS WILL ALLOW SHORTWAVE TO APPROACH FROM THE SW AND CLOUDS WILL
BEGIN TO INCREASE AHEAD OF APPROACHING GULF TROPICAL SYSTEM
OVERNIGHT. LOW TEMPS WILL BE ABOVE AVG.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 305 AM SUNDAY...THE FATE OF THE SHORT TERM WEATHER OBVIOUSLY
HINGES UPON THE EVOLUTION OF HURRICANE IDA. ALTHOUGH THERE IS NOT A
GREAT DEAL OF DISAGREEMENT AMONG CONSENSUS MODEL SOLUTIONS AND NHC
GUIDANCE REGARDING THE TRACK OF THE STORM...THERE IS CONSIDERABLE
DISAGREEMENT ON HOW THE STORM WILL INTERACT WITH VARIOUS SYNOPTIC
FEATURES. THE GFS CONTINUES TO BE THE MOST AGGRESSIVE IN ADVECTING A
PLUME OF TROPICAL MOISTURE OVER MUCH OF THE SOUTHEAST TUESDAY AS A
RESULT OF A STRENGTHENING HEIGHT GRADIENT THAT DEVELOPS IN RESPONSE
TO DIGGING NORTHERN STREAM WAVE AND INTENSIFYING SOUTHERN STREAM
ENERGY PHASING WITH THE IDA CIRCULATION. THIS TROPICAL MOISTURE
COMBINES WITH UPSLOPE/ISENTROPIC LIFT TO PRODUCE HEAVY RAINFALL
ACROSS MUCH OF THE CWFA. THE 12Z ECMWF WAS MORE SUPPRESSED WITH THE
NORTHWARD EXTENT OF THE MOISTURE PLUME...DUE TO MUCH WEAKER MID-
LEVEL FLOW...AND THIS WAS REMINISCENT OF THE GFS ENSEMBLE SUITE.
MUCH OF THE FORECAST WAS LEANED ON THIS 12Z ECMWF/GEFS SCENARIO.
HOWEVER...THE 00Z ECMWF IS NOW VERY SIMILAR TO THE GFS SOLUTION...
WHICH IS DISCONCERTING TO SAY THE LEAST.
POPS HAVE BEEN INCREASED AGAIN TO LIKELY ACROSS THE SOUTHERN HALF OF
THE AREA FOR TUESDAY. HOWEVER...WE WILL CONTINUE TO FEATURE VERY
CONSERVATIVE QPF NUMBERS UNTIL MORE CONFIDENCE CAN BE GLEANED FROM
MODEL SOLUTIONS. ANY PRECIPITATION IS EXPECTED TO END RATHER QUICKLY
TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 315 AM SUNDAY...COOL/DRY HIGH PRESSURE IS EXPECTED TO SETTLE
IN BEHIND A COLD FRONT FOR MUCH OF THE MEDIUM RANGE. THIS WIL RESULT
IN A POP-LESS FORECAST WITH TEMPS EXPECTED TO AVERAGE AROUND NORMAL
THROUGH THE PERIOD.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
AT KCLT AND ELSEWHERE...DRY HIGH PRESSURE WILL REMAIN OVER THE AREA
THROUGH THE PERIOD. CALM TO LGT AND VRBL WINDS EARLY THIS MRNG WILL
BECOME LGT S TO SE TOWARD NOON...ALTHOUGH THEY MAY BE A BIT
SQUIRRELY THRU THE AFTN BUT LESS THAN 10KT. EXPECT SCT HIGH CLOUDS
BY THIS AFTN.
OUTLOOK...VFR CONDITIONS UNDER HIGH PRESSURE WILL CONTINUE THRU MON.
AREAS OF MORNING FOG WILL BE POSSIBLE...ESP AROUND RIVERS AND LAKES.
A COLD FRONT IS EXPECTED TO MOVE IN TUE WITH INCRSNG CHC SHWRS AND
CIG/VSBY RESTRICTIONS. FRONT SHOULD MOVE E WED WITH VFR RETURNING.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...RB/RWH
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...RB
000
FXUS62 KCHS 081524
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1024 AM EST SUN NOV 8 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH
TONIGHT. HURRICANE IDA WILL LIFT NORTH INTO THE GULF OF MEXICO
TONIGHT AND MONDAY BEFORE LAKING LANDFALL AS A LARGE NON-TROPICAL
LOW ALONG THE NORTHERN GULF COAST TUESDAY MORNING. IDA/S REMNANT
LOW WILL MOVE EAST WEDNESDAY AND EMERGE OFF THE NORTHEAST FLORIDA
COAST THURSDAY RESULTING IN UNSETTLED CONDITIONS OVER THE REGION.
HIGH PRESSURE WILL THEN BUILD BACK INTO THE REGION BY FRIDAY AND
REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE FIRST PART OF NEXT
WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NO SIGNIFICANT CHANGES WERE MADE THE GRIDS THIS MORNING. HIGH
PRESSURE BOTH AT THE SURFACE AND ALOFT WILL REMAIN ANCHORED TO THE
REGION TODAY RESULTING IN A CONTINUATION OF DRY AND SEASONABLE
WEATHER. LOW-LEVEL THICKNESSES GENERALLY SUPPORT HIGHS IN THE MID
70S WITH COOLER TEMPERATURES AT THE COAST WHERE AN ONSHORE FLOW
WILL HELP MODERATE CONDITIONS THERE SOMEWHAT. MEAN LOW-LEVEL
TRAJECTORIES SUGGEST THE BULK OF THE CLOSED CELL CUMULUS OVER THE
WESTERN WALL OF THE GULF STREAM WILL REMAIN EAST AND SOUTH OF THE
FORECAST AREA TODAY...ALTHOUGH SOME IT COULD BRUSH PARTS OF
MCINTOSH COUNTY LATER IN THE AFTERNOON. FORECAST SOUNDINGS SUPPORT
A FEW PATCHES OF SHALLOW CUMULUS DEVELOPING LATER TODAY...MAINLY
SOUTH OF I-16 AND JUST INLAND ALONG THE LOWER SOUTH CAROLINA
COAST...BUT WE REALLY DO NOT EXPECT TOO MUCH IN THE WAY OF CLOUD
COVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
HURRICANE IDA IS FORECAST TO TRACK NORTH ACROSS THE CENTRAL GULF
OF MEXICO BY THE NATIONAL HURRICANE CENTER...WHILE STRONG HIGH
PRESSURE REMAINS IN PLACE NORTH OF THE REGION. THE SURFACE
PRESSURE GRADIENT BETWEEN THESE TWO SYSTEMS WILL BEGIN TO TIGHTEN
OVER THE REGION TONIGHT...PREVENTING WINDS FROM DECOUPLING ACROSS
COASTAL AREAS. CIRRUS SHOULD BEGIN TO INCREASE/THICKEN FROM THE
SOUTH TONIGHT...WHILE THE PERSISTENT LOW LEVEL ONSHORE FLOW COULD
ALLOW SOME STRATOCUMULUS TO ADVECT INLAND LATER IN THE NIGHT. THE
INCREASED CLOUD COVER AND/OR LACK OF DECOUPLED WINDS SHOULD LIMIT
COOLING TONIGHT...KEEPING LOWS IN THE MID TO UPPER 50S TOWARD THE
COAST. AREAS FARTHER INLAND COULD SEE LOWS AROUND 50 OR IN THE
LOWER 50S DUE TO LIGHTER WINDS HOWEVER.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
FAIRLY GOOD MODEL AGREEMENT THIS PERIOD EXCEPT FOR THE EVOLUTION
OF TROPICAL CYCLONE IDA AND ITS REMNANTS FOR EARLY TO MID WEEK.
HIGH PRESSURE TO THE NORTH WILL CONTINUE THROUGH MONDAY BEFORE THE
THE HIGH BEGINS TO BREAK DOWN DUE TO THE APPROACH OF A SURFACE LOW
PRESSURE FROM THE SOUTH /TROPICAL CYCLONE IDA/ AND AN UPPER-LEVEL
TROUGH FROM THE WEST. ALTHOUGH TC IDA WILL BE TRANSITIONING INTO AN
EXTRA-TROPICAL SYSTEM NEAR THE GULF COAST TUESDAY...PLENTY OF DEEP
MOISTURE WILL BE PULLED INTO THE AREA AHEAD OF THE STORM AND THE
UPPER TROUGH. WILL CONTINUE TO CARRY LIKELY RAIN CHANCES
TUESDAY/TUESDAY NIGHT. IMPROVING CONDITIONS ARE THEN EXPECTED
WEDNESDAY AS THE UPPER TROUGH SHIFTS OFFSHORE TAKING THE DEEP
MOISTURE WITH IT. STILL LOOKING AT THE POTENTIAL FOR A FEW INCHES OF
RAIN WITH THIS EVENT BUT WITH THE RECENT DRY WEATHER WE DO NOT
EXPECT ANY FLOODING PROBLEMS AT THIS POINT. THUNDER PROSPECTS APPEAR
TOO LOW TO MENTION AT THIS TIME...BUT THERE IS A CHANCE ON TUE/TUE
NIGHT IF THE WARM SECTOR GETS INTO THE AREA.
TEMPERATURES WILL GENERALLY BE NEAR NORMAL THROUGH THE PERIOD EXCEPT
FOR WELL ABOVE NORMAL TEMPERATURES MONDAY AND SATURDAY.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL PREVAIL AT KCHS AND KSAV THROUGH 12Z MONDAY.
CLEAR SKIES AND CALM WINDS WILL PERSIST INTO MID-MORNING...
WITH AN EASTERLY FLOW DEVELOPING LATE THIS MORNING AND THIS
AFTERNOON WITH SPEEDS LESS THAN 10 KT. THE ONSHORE FLOW COULD
RESULT IN A FEW CUMULUS DEVELOPING DURING THE AFTERNOON NEAR
KSAV...OTHERWISE SOME INCREASING HIGH CLOUDINESS IS EXPECTED FROM
THE SOUTH THROUGH TONIGHT.
EXTENDED AVIATION OUTLOOK....VFR CONDITIONS WILL PREVAIL THROUGH
MON. POTENTIAL FOR MVFR OR IFR CONDITIONS MON NIGHT THROUGH WED.
LLWS ALSO POSSIBLE WED MORNING. VFR CONDITIONS EXPECTED WED NIGHT
INTO THU.
&&
.MARINE...
SEAS ARE UP TO 4 FT AT 41008 WHICH IS A LITTLE FASTER THAN
EXPECTED. OPTED TO MOVE THE START TIME OF THE SMALL CRAFT ADVISORY
FOR THE GEORGIA OFFSHORE WATERS UP BY SEVERAL HOURS AS A RESULT.
OTHERWISE E/NE WINDS WILL CONTINUE TODAY WITH SEAS 2-4 FT
NEARSHORE WATERS AND BUILDING TO 4-5 FT OFFSHORE WATERS. LATEST
NHC FORECAST PLACES THE REMNANT LOW OF IDA OFF THE NE FLORIDA
COAST THU MORNING. PER COORD WITH JAX...NO CHANGES WILL BE MADE TO
THURSDAY/S FORECAST BUT SOME CHANGES MAY BE NEEDED FOR THE
AFTERNOON FORECAST PACKAGE.
THE SURFACE PRESSURE GRADIENT BETWEEN HIGH PRESSURE OVER THE
WESTERN ATLANTIC AND HURRICANE IDA MOVING ACROSS THE CENTRAL GULF
OF MEXICO WILL BEGIN TO TIGHTEN OVER THE WATERS TONIGHT. THIS WILL
CAUSE ONSHORE WINDS TO INCREASE TO AS HIGH AS 15 KT OVER THE NEAR
SHORE WATERS AND 15-20 KT OVER THE OUTER GEORGIA WATERS. THE
FAVORABLE FETCH WILL ALLOW SEAS TO BUILD AS WELL...AND A SMALL
CRAFT ADVISORY HAS BEEN ISSUED FOR THE OUTER GEORGIA WATERS
BEGINNING AT MIDNIGHT AS A RESULT.
MONDAY THROUGH THURSDAY...HIGH PRES TO THE N WILL GIVE WAY TO A LOW
PRES SYSTEM APPROACHING FROM THE SW /TC IDA OR ITS REMNANTS/ MON AND
MON NIGHT. MEANWHILE...AN APPROACHING UPPER TROUGH OF LOW PRES LOOKS
TO PICK UP TC IDA /OR PART OF THE SYSTEM/ AND MOVE IT NE OVER/NEAR
THE MARINE AREA TUE/TUE NIGHT. HIGH PRES WILL THEN BUILD IN BEHIND
THE DEPARTING LOW WED/THU. DUE TO THE CONSIDERABLE UNCERTAINTY WITH
THE EVOLUTION OF TC IDA AND ITS REMNANTS...MARINERS ARE REMINDED
THAT THERE IS QUITE A BIT OF FORECAST UNCERTAINTY AT THIS TIME.
ONGOING SCA CONDITIONS ACROSS THE GA WATERS BEYOND 20 NM ARE LIKELY
TO TRANSITION INTO THE COASTAL WATERS WITHIN 20 NM MON NIGHT AS SEAS
BUILD TO 6 FT. A VERY STRONG PRES GRADIENT WILL EVENTUALLY SET UP
B/W THE DEPARTING LOW AND A BUILDING HIGH PRES SYSTEM INLAND TUE
NIGHT/WED. IT IS DURING THIS TIME THAT GALES ARE POSSIBLE...
ESPECIALLY ACROSS THE WATERS BEYOND 20 NM FROM SHORE. IMPROVING
CONDS EXPECTED THU WITH NO HEADLINES EXPECTED WITHIN THE NEARSHORE
WATERS BY THU NIGHT.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 9 PM THIS EVENING TO 10 AM EST
THURSDAY FOR AMZ374.
&&
$$
000
FXUS62 KGSP 081314
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
814 AM EST SUN NOV 8 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
ABUNDANT MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS THEN
EXPECTED TO MOVE INTO THE CAROLINAS AND NORTH GEORGIA AHEAD OF A
COLD FRONT ON TUESDAY...WITH THE FRONT EXPECTED TO CROSS THE AREA
LATE TUESDAY INTO EARLY WEDNESDAY. HIGH PRESSURE WILL THEN RETURN
FOR THE LATER HALF OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATING TO REMOVE FROST ADV. NO CHANGES TO FCST FOR NOW.
PREVIOUS DISCUSSION...UPPER RIDGE WILL CONTINUE TO BUILD OVER THE
REGION TODAY. THICKNESS WILL INCREASE AND LGT SLY WINDS WITH FULL
SUN WILL BRING TEMPS UP ABOUT 10 DEGREES ABOVE AVG FOR THIS TIME OF
YEAR. UPPER RIDGE WILL CONT TO BUILD THIS EVE BEFORE AXIS STARTS TO
TRACK E. THIS WILL ALLOW SHORTWAVE TO APPROACH FROM THE SW AND
CLOUDS WILL BEGIN TO INCREASE AHEAD OF APPROACHING GULF TROPICAL
SYSTEM OVERNIGHT. LOW TEMPS WILL BE ABOVE AVG.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 305 AM SUNDAY...THE FATE OF THE SHORT TERM WEATHER OBVIOUSLY
HINGES UPON THE EVOLUTION OF HURRICANE IDA. ALTHOUGH THERE IS NOT A
GREAT DEAL OF DISAGREEMENT AMONG CONSENSUS MODEL SOLUTIONS AND NHC
GUIDANCE REGARDING THE TRACK OF THE STORM...THERE IS CONSIDERABLE
DISAGREEMENT ON HOW THE STORM WILL INTERACT WITH VARIOUS SYNOPTIC
FEATURES. THE GFS CONTINUES TO BE THE MOST AGGRESSIVE IN ADVECTING A
PLUME OF TROPICAL MOISTURE OVER MUCH OF THE SOUTHEAST TUESDAY AS A
RESULT OF A STRENGTHENING HEIGHT GRADIENT THAT DEVELOPS IN RESPONSE
TO DIGGING NORTHERN STREAM WAVE AND INTENSIFYING SOUTHERN STREAM
ENERGY PHASING WITH THE IDA CIRCULATION. THIS TROPICAL MOISTURE
COMBINES WITH UPSLOPE/ISENTROPIC LIFT TO PRODUCE HEAVY RAINFALL
ACROSS MUCH OF THE CWFA. THE 12Z ECMWF WAS MORE SUPPRESSED WITH THE
NORTHWARD EXTENT OF THE MOISTURE PLUME...DUE TO MUCH WEAKER MID-
LEVEL FLOW...AND THIS WAS REMINISCENT OF THE GFS ENSEMBLE SUITE.
MUCH OF THE FORECAST WAS LEANED ON THIS 12Z ECMWF/GEFS SCENARIO.
HOWEVER...THE 00Z ECMWF IS NOW VERY SIMILAR TO THE GFS SOLUTION...
WHICH IS DISCONCERTING TO SAY THE LEAST.
POPS HAVE BEEN INCREASED AGAIN TO LIKELY ACROSS THE SOUTHERN HALF OF
THE AREA FOR TUESDAY. HOWEVER...WE WILL CONTINUE TO FEATURE VERY
CONSERVATIVE QPF NUMBERS UNTIL MORE CONFIDENCE CAN BE GLEANED FROM
MODEL SOLUTIONS. ANY PRECIPITATION IS EXPECTED TO END RATHER QUICKLY
TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 315 AM SUNDAY...COOL/DRY HIGH PRESSURE IS EXPECTED TO SETTLE
IN BEHIND A COLD FRONT FOR MUCH OF THE MEDIUM RANGE. THIS WIL RESULT
IN A POP-LESS FORECAST WITH TEMPS EXPECTED TO AVERAGE AROUND NORMAL
THROUGH THE PERIOD.
&&
.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
AT KCLT AND ELSEWHERE...DRY HIGH PRESSURE WILL REMAIN OVER THE AREA
THROUGH THE PERIOD. CALM TO LGT AND VRBL WINDS EARLY THIS MRNG WILL
BECOME LGT S TO SE TOWARD NOON...ALTHOUGH THEY MAY BE A BIT
SQUIRRELY THRU THE AFTN BUT LESS THAN 10KT. EXPECT SCT HIGH CLOUDS
BY THIS AFTN.
OUTLOOK...VFR CONDITIONS UNDER HIGH PRESSURE WILL CONTINUE THRU MON.
AREAS OF MORNING FOG WILL BE POSSIBLE...ESP AROUND RIVERS AND LAKES.
A COLD FRONT IS EXPECTED TO MOVE IN TUE WITH INCRSNG CHC SHWRS AND
CIG/VSBY RESTRICTIONS. FRONT SHOULD MOVE E WED WITH VFR RETURNING.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...RB/RWH
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...RB
000
FXUS62 KCAE 081140
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
640 AM EST SUN NOV 8 2009
.SYNOPSIS...
DRY HIGH PRESSURE EXTENDING INTO THE FORECAST AREA WILL CONTINUE TO
DOMINATE THROUGH MONDAY. A COLD FRONT ALONG WITH A SURGE OF TROPICAL
MOISTURE WILL AFFECT THE AREA MAINLY TUESDAY AND TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DRY HIGH PRESSURE RIDGING INTO THE FORECAST AREA WILL CONTINUE TO
DOMINATE TODAY. USED THE COOLER TEMPERATURE GUIDANCE BECAUSE OF
VERIFICATION THE PAST FEW DAYS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
THE MODELS AGREED KEEPING DRY HIGH PRESSURE IN CONTROL TONIGHT
THROUGH MONDAY. THE GFS WAS FASTER MOVING MOISTURE AND SIGNIFICANT
ISENTROPIC LIFT INTO THE FORECAST AREA LATE MONDAY NIGHT COMPARED
TO THE NAM. THE MAV MOS INDICATED CATEGORICAL POPS MONDAY NIGHT. THE
MET MOS WAS MUCH LOWER. KEPT POPS LESS THAN 20 PERCENT THROUGH
MONDAY WITH CHANCE POPS MONDAY NIGHT. THE CHANCE POPS MONDAY NIGHT
WERE AN AVERAGE OF THE MAV AND MET MOS. STRONG RADIATIONAL COOLING
SUPPORTED THE COOLER GUIDANCE TEMPERATURES TONIGHT. USED THE
GUIDANCE CONSENSUS FOR THE REST OF THE TEMPERATURE FORECAST.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE MAIN FORECAST PROBLEM IS THE IMPACT OF TROPICAL MOISTURE
ASSOCIATED WITH IDA. CONFIDENCE IS LOW BECAUSE OF MODEL
INCONSISTENCY. THE GFS SHOWED DEEP MOISTURE AND STRONG ISENTROPIC
LIFT TUESDAY. IT INDICATED H85 WINDS NEAR 45 KNOTS WITH AN
INVERTED SURFACE TROUGH EXTENDING THROUGH THE FORECAST AREA. THIS
SUPPORTED A SEVERE THUNDERSTORM AND FLOOD THREAT. THE NAM WAS
SLOWER AND SHOWED LESS ISENTROPIC LIFT AND DEEPER MOISTURE
SUPPRESSED FARTHER SOUTH. THE 12Z SATURDAY ECMWF WAS CLOSER TO
THE NAM. THE 00Z SUNDAY ECMWF WAS CLOSER TO THE GFS WITH RESPECT
TO SPREADING THE DEEP MOISTURE NORTHWARD...BUT WAS SLOWER. BELIEVE
THE BEST FORECAST FOR NOW IS TO ADJUST POPS UPWARD SLIGHTLY BASED
ON THE ECMWF TREND WITH POPS LIKELY TUESDAY AND TUESDAY NIGHT.
THE MODELS ARE IN GOOD AGREEMENT SHOWING DRY HIGH PRESSURE
DOMINATING THURSDAY THROUGH SATURDAY.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
PATCHY MVFR CONDITIONS IN EARLY MORNING FOG WILL QUICKLY GIVE WAY
TO VFR CONDITIONS. HIGH PRESSURE ALONG WITH LIGHT AND VARIABLE
WINDS WILL CONTINUE TO DOMINATE THE REGION THROUGH THE TAF PERIOD.
MAIN CONCERN WILL BE POTENTIAL FOR FOG AFTER 09/06Z...WITH THE
HIGH BEGINNING TO SLIDE AWAY FROM THE AREA EXPECT POSSIBLE MVFR
FOG. CURRENTLY HAVE LEFT FOG FOR 09/06Z AND LATER OUT OF TAFS
UNTIL CONFIDENCE INCREASES.
EXTENDED AVIATION OUTLOOK...WIDESPREAD CEILING AND VISIBILITY
RESTRICTIONS MAY OCCUR TUESDAY INTO WEDNESDAY ASSOCIATED WITH
AN APPROACHING FRONT AND MOISTURE FROM TS IDA.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...FROST ADVISORY UNTIL 7 AM EST THIS MORNING FOR SCZ015-016-
020>022.
GA...NONE.
&&
$$
000
FXUS62 KCHS 081125
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
625 AM EST SUN NOV 8 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH
TONIGHT. THE COMBINATION OF HURRICANE IDA...OR ITS REMNANTS...
LIFTING NORTHWARD THROUGH THE GULF OF MEXICO AND A COLD FRONT
APPROACHING FROM THE NORTHWEST WILL RESULT IN UNSETTLED CONDITIONS
DURING THE EARLY TO MIDDLE PART OF THIS WEEK. HIGH PRESSURE WILL THEN
BUILD BACK INTO THE REGION BY THURSDAY AND REMAIN THE DOMINANT
WEATHER FEATURE THROUGH THE FIRST PART OF NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AN UPPER LEVEL RIDGE OF HIGH PRESSURE WILL PREVAIL OVER THE
SOUTHEASTERN UNITED STATES TODAY...WHILE EXPANSIVE HIGH PRESSURE
AT THE SURFACE REMAINS OVER THE WESTERN ATLANTIC.
GIVEN HIGH PRESSURE AT THE SURFACE AND ALOFT...STRONG SUBSIDENCE
WILL BE IN PLACE TODAY. THE ONSHORE FLOW WILL ALLOW FOR A SLIGHT
INCREASE IN LOW LEVEL MOISTURE...WHICH MAY SUPPORT THE DEVELOPMENT
OF A FEW CUMULUS CLOUDS THIS AFTERNOON. THIN CIRRUS MAY ALSO BEGIN
TO INCREASE FROM THE SOUTH DURING THE DAY. HOWEVER...SKIES WILL
GENERALLY REMAIN SUNNY OR MOSTLY SUNNY ACROSS THE AREA.
THE STRONG RIDGING ALOFT WILL RESULT IN ABOVE NORMAL TEMPERATURES
TODAY...WITH LOW LEVEL THICKNESS VALUES SUPPORTING HIGHS OF 76 OR
77. AREAS ALONG THE IMMEDIATE COAST WILL BE SIGNIFICANTLY
COOLER...AROUND 70...DUE TO THE ONSHORE FLOW.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
HURRICANE IDA IS FORECAST TO TRACK NORTH ACROSS THE CENTRAL GULF
OF MEXICO BY THE NATIONAL HURRICANE CENTER...WHILE STRONG HIGH
PRESSURE REMAINS IN PLACE NORTH OF THE REGION. THE SURFACE
PRESSURE GRADIENT BETWEEN THESE TWO SYSTEMS WILL BEGIN TO TIGHTEN
OVER THE REGION TONIGHT...PREVENTING WINDS FROM DECOUPLING ACROSS
COASTAL AREAS. CIRRUS SHOULD BEGIN TO INCREASE/THICKEN FROM THE
SOUTH TONIGHT...WHILE THE PERSISTENT LOW LEVEL ONSHORE FLOW COULD
ALLOW SOME STRATOCUMULUS TO ADVECT INLAND LATER IN THE NIGHT. THE
INCREASED CLOUD COVER AND/OR LACK OF DECOUPLED WINDS SHOULD LIMIT
COOLING TONIGHT...KEEPING LOWS IN THE MID TO UPPER 50S TOWARD THE
COAST. AREAS FARTHER INLAND COULD SEE LOWS AROUND 50 OR IN THE
LOWER 50S DUE TO LIGHTER WINDS HOWEVER.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
FAIRLY GOOD MODEL AGREEMENT THIS PERIOD EXCEPT FOR THE EVOLUTION
OF TROPICAL CYCLONE IDA AND ITS REMNANTS FOR EARLY TO MID WEEK.
HIGH PRESSURE TO THE NORTH WILL CONTINUE THROUGH MONDAY BEFORE THE
THE HIGH BEGINS TO BREAK DOWN DUE TO THE APPROACH OF A SURFACE LOW
PRESSURE FROM THE SOUTH /TROPICAL CYCLONE IDA/ AND AN UPPER-LEVEL
TROUGH FROM THE WEST. ALTHOUGH TC IDA WILL BE TRANSITIONING INTO AN
EXTRA-TROPICAL SYSTEM NEAR THE GULF COAST TUESDAY...PLENTY OF DEEP
MOISTURE WILL BE PULLED INTO THE AREA AHEAD OF THE STORM AND THE
UPPER TROUGH. WILL CONTINUE TO CARRY LIKELY RAIN CHANCES
TUESDAY/TUESDAY NIGHT. IMPROVING CONDITIONS ARE THEN EXPECTED
WEDNESDAY AS THE UPPER TROUGH SHIFTS OFFSHORE TAKING THE DEEP
MOISTURE WITH IT. STILL LOOKING AT THE POTENTIAL FOR A FEW INCHES OF
RAIN WITH THIS EVENT BUT WITH THE RECENT DRY WEATHER WE DO NOT
EXPECT ANY FLOODING PROBLEMS AT THIS POINT. THUNDER PROSPECTS APPEAR
TOO LOW TO MENTION AT THIS TIME...BUT THERE IS A CHANCE ON TUE/TUE
NIGHT IF THE WARM SECTOR GETS INTO THE AREA.
TEMPERATURES WILL GENERALLY BE NEAR NORMAL THROUGH THE PERIOD EXCEPT
FOR WELL ABOVE NORMAL TEMPERATURES MONDAY AND SATURDAY.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL PREVAIL AT KCHS AND KSAV THROUGH 12Z MONDAY.
CLEAR SKIES AND CALM WINDS WILL PERSIST INTO MID-MORNING...
WITH AN EASTERLY FLOW DEVELOPING LATE THIS MORNING AND THIS
AFTERNOON WITH SPEEDS LESS THAN 10 KT. THE ONSHORE FLOW COULD
RESULT IN A FEW CUMULUS DEVELOPING DURING THE AFTERNOON NEAR
KSAV...OTHERWISE SOME INCREASING HIGH CLOUDINESS IS EXPECTED FROM
THE SOUTH THROUGH TONIGHT.
EXTENDED AVIATION OUTLOOK....VFR CONDITIONS WILL PREVAIL THROUGH
MON. POTENTIAL FOR MVFR OR IFR CONDITIONS MON NIGHT THROUGH WED.
LLWS ALSO POSSIBLE WED MORNING. VFR CONDITIONS EXPECTED WED NIGHT
INTO THU.
&&
.MARINE...
RATHER BENIGN CONDITIONS ARE EXPECTED OVER THE COASTAL WATERS
TODAY AS HIGH PRESSURE OVER THE WESTERN ATLANTIC REMAINS IN PLACE.
WINDS WILL VEER FROM NORTHEAST TO EAST THIS AFTERNOON...WITH
SPEEDS LESS THAN 15 KT THROUGHOUT THE WATERS. DESPITE A LACK OF
SIGNIFICANT WIND WAVES...THE PERSISTENT ONSHORE FLOW COULD KEEP SEAS
UP AS HIGH AS 2-4 FT AS WEAK EASTERLY SWELLS IMPACT THE WATERS.
THE SURFACE PRESSURE GRADIENT BETWEEN HIGH PRESSURE OVER THE
WESTERN ATLANTIC AND HURRICANE IDA MOVING ACROSS THE CENTRAL GULF
OF MEXICO WILL BEGIN TO TIGHTEN OVER THE WATERS TONIGHT. THIS WILL
CAUSE ONSHORE WINDS TO INCREASE TO AS HIGH AS 15 KT OVER THE NEAR
SHORE WATERS AND 15-20 KT OVER THE OUTER GEORGIA WATERS. THE
FAVORABLE FETCH WILL ALLOW SEAS TO BUILD AS WELL...AND A SMALL
CRAFT ADVISORY HAS BEEN ISSUED FOR THE OUTER GEORGIA WATERS
BEGINNING AT MIDNIGHT AS A RESULT.
MONDAY THROUGH THURSDAY...HIGH PRES TO THE N WILL GIVE WAY TO A LOW
PRES SYSTEM APPROACHING FROM THE SW /TC IDA OR ITS REMNANTS/ MON AND
MON NIGHT. MEANWHILE...AN APPROACHING UPPER TROUGH OF LOW PRES LOOKS
TO PICK UP TC IDA /OR PART OF THE SYSTEM/ AND MOVE IT NE OVER/NEAR
THE MARINE AREA TUE/TUE NIGHT. HIGH PRES WILL THEN BUILD IN BEHIND
THE DEPARTING LOW WED/THU. DUE TO THE CONSIDERABLE UNCERTAINTY WITH
THE EVOLUTION OF TC IDA AND ITS REMNANTS...MARINERS ARE REMINDED
THAT THERE IS QUITE A BIT OF FORECAST UNCERTAINTY AT THIS TIME.
ONGOING SCA CONDITIONS ACROSS THE GA WATERS BEYOND 20 NM ARE LIKELY
TO TRANSITION INTO THE COASTAL WATERS WITHIN 20 NM MON NIGHT AS SEAS
BUILD TO 6 FT. A VERY STRONG PRES GRADIENT WILL EVENTUALLY SET UP
B/W THE DEPARTING LOW AND A BUILDING HIGH PRES SYSTEM INLAND TUE
NIGHT/WED. IT IS DURING THIS TIME THAT GALES ARE
POSSIBLE...ESPECIALLY ACROSS THE WATERS BEYOND 20 NM FROM SHORE.
IMPROVING CONDS EXPECTED THU WITH NO HEADLINES EXPECTED WITHIN THE
NEARSHORE WATERS BY THU NIGHT.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM EST FRIDAY
FOR AMZ374.
&&
$$
JAQ/RJB
000
FXUS62 KGSP 081110
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
610 AM EST SUN NOV 8 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
ABUNDANT MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS EXPECTED TO
MOVE INTO THE CAROLINAS AND NORTH GEORGIA AHEAD OF A COLD FRONT ON
TUESDAY...WITH THE FRONT EXPECTED TO CROSS THE AREA LATE TUESDAY
INTO EARLY WEDNESDAY. HIGH PRESSURE WILL THEN RETURN FOR THE LATER
HALF OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPPER RIDGE WILL CONTINUE TO BUILD OVER THE REGION TODAY. THICKNESS
WILL INCREASE AND LGT SLY WINDS WITH FULL SUN WILL BRING TEMPS UP
ABOUT 10 DEGREES ABOVE AVG FOR THIS TIME OF YEAR. UPPER RIDGE WILL
CONT TO BUILD THIS EVE BEFORE AXIS STARTS TO TRACK E. THIS WILL
ALLOW SHORTWAVE TO APPROACH FROM THE SW AND CLOUDS WILL BEGIN TO
INCREASE AHEAD OF APPROACHING GULF TROPICAL SYSTEM OVERNIGHT. LOW
TEMPS WILL BE ABOVE AVG.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 305 AM SUNDAY...THE FATE OF THE SHORT TERM WEATHER OBVIOUSLY
HINGES UPON THE EVOLUTION OF HURRICANE IDA. ALTHOUGH THERE IS NOT A
GREAT DEAL OF DISAGREEMENT AMONG CONSENSUS MODEL SOLUTIONS AND NHC
GUIDANCE REGARDING THE TRACK OF THE STORM...THERE IS CONSIDERABLE
DISAGREEMENT ON HOW THE STORM WILL INTERACT WITH VARIOUS SYNOPTIC
FEATURES. THE GFS CONTINUES TO BE THE MOST AGGRESSIVE IN ADVECTING A
PLUME OF TROPICAL MOISTURE OVER MUCH OF THE SOUTHEAST TUESDAY AS A
RESULT OF A STRENGTHENING HEIGHT GRADIENT THAT DEVELOPS IN RESPONSE
TO DIGGING NORTHERN STREAM WAVE AND INTENSIFYING SOUTHERN STREAM
ENERGY PHASING WITH THE IDA CIRCULATION. THIS TROPICAL MOISTURE
COMBINES WITH UPSLOPE/ISENTROPIC LIFT TO PRODUCE HEAVY RAINFALL
ACROSS MUCH OF THE CWFA. THE 12Z ECMWF WAS MORE SUPPRESSED WITH THE
NORTHWARD EXTENT OF THE MOISTURE PLUME...DUE TO MUCH WEAKER MID-
LEVEL FLOW...AND THIS WAS REMINISCENT OF THE GFS ENSEMBLE SUITE.
MUCH OF THE FORECAST WAS LEANED ON THIS 12Z ECMWF/GEFS SCENARIO.
HOWEVER...THE 00Z ECMWF IS NOW VERY SIMILAR TO THE GFS SOLUTION...
WHICH IS DISCONCERTING TO SAY THE LEAST.
POPS HAVE BEEN INCREASED AGAIN TO LIKELY ACROSS THE SOUTHERN HALF OF
THE AREA FOR TUESDAY. HOWEVER...WE WILL CONTINUE TO FEATURE VERY
CONSERVATIVE QPF NUMBERS UNTIL MORE CONFIDENCE CAN BE GLEANED FROM
MODEL SOLUTIONS. ANY PRECIPITATION IS EXPECTED TO END RATHER QUICKLY
TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 315 AM SUNDAY...COOL/DRY HIGH PRESSURE IS EXPECTED TO SETTLE
IN BEHIND A COLD FRONT FOR MUCH OF THE MEDIUM RANGE. THIS WIL RESULT
IN A POP-LESS FORECAST WITH TEMPS EXPECTED TO AVERAGE AROUND NORMAL
THROUGH THE PERIOD.
&&
.AVIATION /11Z SUNDAY THROUGH THURSDAY/...
AT KCLT AND ELSEWHERE...DRY HIGH PRESSURE WILL REMAIN OVER THE AREA
THROUGH THE PERIOD. CALM TO LGT AND VRBL WINDS EARLY THIS MRNG WILL
BECOME LGT S TO SE TOWARD NOON...ALTHOUGH THEY MAY BE A BIT
SQUIRRELY THRU THE AFTN BUT LESS THAN 10KT. EXPECT SCT HIGH CLOUDS
BY THIS AFTN.
OUTLOOK...VFR CONDITIONS UNDER HIGH PRESSURE WILL CONTINUE THRU MON.
AREAS OF MORNING FOG WILL BE POSSIBLE...ESP AROUND RIVERS AND LAKES.
A COLD FRONT IS EXPECTED TO MOVE IN TUE WITH INCRSNG CHC SHWRS AND
CIG/VSBY RESTRICTIONS. FRONT SHOULD MOVE E WED WITH VFR RETURNING.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FROST ADVISORY UNTIL 8 AM EST THIS MORNING FOR GAZ028-029.
NC...FROST ADVISORY UNTIL 8 AM EST THIS MORNING FOR NCZ068>072-082.
SC...FROST ADVISORY UNTIL 8 AM EST THIS MORNING FOR SCZ008>014-019.
&&
$$
SYNOPSIS...JPT
NEAR TERM...RB
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...RB
000
FXUS62 KCHS 080832
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
332 AM EST SUN NOV 8 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH
TONIGHT. THE COMBINATION OF HURRICANE IDA...OR ITS REMNANTS...
LIFTING NORTHWARD THROUGH THE GULF OF MEXICO AND A COLD FRONT
APPROACHING FROM THE NORTHWEST WILL RESULT IN UNSETTLED CONDITIONS
DURING THE EARLY TO MIDDLE PART OF THIS WEEK. HIGH PRESSURE WILL THEN
BUILD BACK INTO THE REGION BY THURSDAY AND REMAIN THE DOMINANT
WEATHER FEATURE THROUGH THE FIRST PART OF NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
AN UPPER LEVEL RIDGE OF HIGH PRESSURE WILL PREVAIL OVER THE
SOUTHEASTERN UNITED STATES TODAY...WHILE EXPANSIVE HIGH PRESSURE
AT THE SURFACE REMAINS OVER THE WESTERN ATLANTIC.
GIVEN HIGH PRESSURE AT THE SURFACE AND ALOFT...STRONG SUBSIDENCE
WILL BE IN PLACE TODAY. THE ONSHORE FLOW WILL ALLOW FOR A SLIGHT
INCREASE IN LOW LEVEL MOISTURE...WHICH MAY SUPPORT THE DEVELOPMENT
OF A FEW CUMULUS CLOUDS THIS AFTERNOON. THIN CIRRUS MAY ALSO BEGIN
TO INCREASE FROM THE SOUTH DURING THE DAY. HOWEVER...SKIES WILL
GENERALLY REMAIN SUNNY OR MOSTLY SUNNY ACROSS THE AREA.
THE STRONG RIDGING ALOFT WILL RESULT IN ABOVE NORMAL TEMPERATURES
TODAY...WITH LOW LEVEL THICKNESS VALUES SUPPORTING HIGHS OF 76 OR
77. AREAS ALONG THE IMMEDIATE COAST WILL BE SIGNIFICANTLY
COOLER...AROUND 70...DUE TO THE ONSHORE FLOW.
&&
.SHORT TERM /TONIGHT/...
HURRICANE IDA IS FORECAST TO TRACK NORTH ACROSS THE CENTRAL GULF
OF MEXICO BY THE NATIONAL HURRICANE CENTER...WHILE STRONG HIGH
PRESSURE REMAINS IN PLACE NORTH OF THE REGION. THE SURFACE
PRESSURE GRADIENT BETWEEN THESE TWO SYSTEMS WILL BEGIN TO TIGHTEN
OVER THE REGION TONIGHT...PREVENTING WINDS FROM DECOUPLING ACROSS
COASTAL AREAS. CIRRUS SHOULD BEGIN TO INCREASE/THICKEN FROM THE
SOUTH TONIGHT...WHILE THE PERSISTENT LOW LEVEL ONSHORE FLOW COULD
ALLOW SOME STRATOCUMULUS TO ADVECT INLAND LATER IN THE NIGHT. THE
INCREASED CLOUD COVER AND/OR LACK OF DECOUPLED WINDS SHOULD LIMIT
COOLING TONIGHT...KEEPING LOWS IN THE MID TO UPPER 50S TOWARD THE
COAST. AREAS FARTHER INLAND COULD SEE LOWS AROUND 50 OR IN THE
LOWER 50S DUE TO LIGHTER WINDS HOWEVER.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
FAIRLY GOOD MODEL AGREEMENT THIS PERIOD EXCEPT FOR THE EVOLUTION
OF TROPICAL CYCLONE IDA AND ITS REMNANTS FOR EARLY TO MID WEEK.
HIGH PRESSURE TO THE NORTH WILL CONTINUE THROUGH MONDAY BEFORE THE
THE HIGH BEGINS TO BREAK DOWN DUE TO THE APPROACH OF A SURFACE LOW
PRESSURE FROM THE SOUTH /TROPICAL CYCLONE IDA/ AND AN UPPER-LEVEL
TROUGH FROM THE WEST. ALTHOUGH TC IDA WILL BE TRANSITIONING INTO AN
EXTRA-TROPICAL SYSTEM NEAR THE GULF COAST TUESDAY...PLENTY OF DEEP
MOISTURE WILL BE PULLED INTO THE AREA AHEAD OF THE STORM AND THE
UPPER TROUGH. WILL CONTINUE TO CARRY LIKELY RAIN CHANCES
TUESDAY/TUESDAY NIGHT. IMPROVING CONDITIONS ARE THEN EXPECTED
WEDNESDAY AS THE UPPER TROUGH SHIFTS OFFSHORE TAKING THE DEEP
MOISTURE WITH IT. STILL LOOKING AT THE POTENTIAL FOR A FEW INCHES OF
RAIN WITH THIS EVENT BUT WITH THE RECENT DRY WEATHER WE DO NOT
EXPECT ANY FLOODING PROBLEMS AT THIS POINT. THUNDER PROSPECTS APPEAR
TOO LOW TO MENTION AT THIS TIME...BUT THERE IS A CHANCE ON TUE/TUE
NIGHT IF THE WARM SECTOR GETS INTO THE AREA.
TEMPERATURES WILL GENERALLY BE NEAR NORMAL THROUGH THE PERIOD EXCEPT
FOR WELL ABOVE NORMAL TEMPERATURES MONDAY AND SATURDAY.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL PREVAIL AT KCHS AND KSAV THROUGH 06Z MONDAY.
CLEAR SKIES AND CALM WINDS WILL PERSIST INTO MID-MORNING...
WITH AN EASTERLY FLOW DEVELOPING LATE THIS MORNING AND THIS
AFTERNOON WITH SPEEDS LESS THAN 10 KT. THE ONSHORE FLOW COULD
RESULT IN A FEW CUMULUS DEVELOPING DURING THE AFTERNOON NEAR
KSAV...OTHERWISE SOME INCREASING HIGH CLOUDINESS IS EXPECTED FROM
THE SOUTH TODAY INTO TONIGHT.
EXTENDED AVIATION OUTLOOK....VFR CONDITIONS WILL PREVAIL THROUGH
MON. POTENTIAL FOR MVFR OR IFR CONDITIONS MON NIGHT THROUGH WED.
LLWS ALSO POSSIBLE WED MORNING. VFR CONDITIONS EXPECTED WED NIGHT
INTO THU.
&&
.MARINE...
RATHER BENIGN CONDITIONS ARE EXPECTED OVER THE COASTAL WATERS
TODAY AS HIGH PRESSURE OVER THE WESTERN ATLANTIC REMAINS IN PLACE.
WINDS WILL VEER FROM NORTHEAST TO EAST THIS AFTERNOON...WITH
SPEEDS LESS THAN 15 KT THROUGHOUT THE WATERS. DESPITE A LACK OF
SIGNIFICANT WIND WAVES...THE PERSISTENT ONSHORE FLOW COULD KEEP SEAS
UP AS HIGH AS 2-4 FT AS WEAK EASTERLY SWELLS IMPACT THE WATERS.
THE SURFACE PRESSURE GRADIENT BETWEEN HIGH PRESSURE OVER THE
WESTERN ATLANTIC AND HURRICANE IDA MOVING ACROSS THE CENTRAL GULF
OF MEXICO WILL BEGIN TO TIGHTEN OVER THE WATERS TONIGHT. THIS WILL
CAUSE ONSHORE WINDS TO INCREASE TO AS HIGH AS 15 KT OVER THE NEAR
SHORE WATERS AND 15-20 KT OVER THE OUTER GEORGIA WATERS. THE
FAVORABLE FETCH WILL ALLOW SEAS TO BUILD AS WELL...AND A SMALL
CRAFT ADVISORY HAS BEEN ISSUED FOR THE OUTER GEORGIA WATERS
BEGINNING AT MIDNIGHT AS A RESULT.
MONDAY THROUGH THURSDAY...HIGH PRES TO THE N WILL GIVE WAY TO A LOW
PRES SYSTEM APPROACHING FROM THE SW /TC IDA OR ITS REMNANTS/ MON AND
MON NIGHT. MEANWHILE...AN APPROACHING UPPER TROUGH OF LOW PRES LOOKS
TO PICK UP TC IDA /OR PART OF THE SYSTEM/ AND MOVE IT NE OVER/NEAR
THE MARINE AREA TUE/TUE NIGHT. HIGH PRES WILL THEN BUILD IN BEHIND
THE DEPARTING LOW WED/THU. DUE TO THE CONSIDERABLE UNCERTAINTY WITH
THE EVOLUTION OF TC IDA AND ITS REMNANTS...MARINERS ARE REMINDED
THAT THERE IS QUITE A BIT OF FORECAST UNCERTAINTY AT THIS TIME.
ONGOING SCA CONDITIONS ACROSS THE GA WATERS BEYOND 20 NM ARE LIKELY
TO TRANSITION INTO THE COASTAL WATERS WITHIN 20 NM MON NIGHT AS SEAS
BUILD TO 6 FT. A VERY STRONG PRES GRADIENT WILL EVENTUALLY SET UP
B/W THE DEPARTING LOW AND A BUILDING HIGH PRES SYSTEM INLAND TUE
NIGHT/WED. IT IS DURING THIS TIME THAT GALES ARE
POSSIBLE...ESPECIALLY ACROSS THE WATERS BEYOND 20 NM FROM SHORE.
IMPROVING CONDS EXPECTED THU WITH NO HEADLINES EXPECTED WITHIN THE
NEARSHORE WATERS BY THU NIGHT.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM EST FRIDAY
FOR AMZ374.
&&
$$
JAQ/RJB
000
FXUS62 KGSP 080823
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
323 AM EST SUN NOV 8 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
ABUNDANT MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS EXPECTED TO
MOVE INTO THE CAROLINAS AND NORTH GEORGIA AHEAD OF A COLD FRONT ON
TUESDAY...WITH THE FRONT EXPECTED TO CROSS THE AREA LATE TUESDAY
INTO EARLY WEDNESDAY. HIGH PRESSURE WILL THEN RETURN FOR THE LATER
HALF OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPPER RIDGE WILL CONTINUE TO BUILD OVER THE REGION TODAY. THICKNESS
WILL INCREASE AND LGT SLY WINDS WITH FULL SUN WILL BRING TEMPS UP
ABOUT 10 DEGREES ABOVE AVG FOR THIS TIME OF YEAR. UPPER RIDGE WILL
CONT TO BUILD THIS EVE BEFORE AXIS STARTS TO TRACK E. THIS WILL
ALLOW SHORTWAVE TO APPROACH FROM THE SW AND CLOUDS WILL BEGIN TO
INCREASE AHEAD OF APPROACHING GULF TROPICAL SYSTEM OVERNIGHT. LOW
TEMPS WILL BE ABOVE AVG.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 305 AM SUNDAY...THE FATE OF THE SHORT TERM WEATHER OBVIOUSLY
HINGES UPON THE EVOLUTION OF HURRICANE IDA. ALTHOUGH THERE IS NOT A
GREAT DEAL OF DISAGREEMENT AMONG CONSENSUS MODEL SOLUTIONS AND NHC
GUIDANCE REGARDING THE TRACK OF THE STORM...THERE IS CONSIDERABLE
DISAGREEMENT ON HOW THE STORM WILL INTERACT WITH VARIOUS SYNOPTIC
FEATURES. THE GFS CONTINUES TO BE THE MOST AGGRESSIVE IN ADVECTING A
PLUME OF TROPICAL MOISTURE OVER MUCH OF THE SOUTHEAST TUESDAY AS A
RESULT OF A STRENGTHENING HEIGHT GRADIENT THAT DEVELOPS IN RESPONSE
TO DIGGING NORTHERN STREAM WAVE AND INTENSIFYING SOUTHERN STREAM
ENERGY PHASING WITH THE IDA CIRCULATION. THIS TROPICAL MOISTURE
COMBINES WITH UPSLOPE/ISENTROPIC LIFT TO PRODUCE HEAVY RAINFALL
ACROSS MUCH OF THE CWFA. THE 12Z ECMWF WAS MORE SUPPRESSED WITH THE
NORTHWARD EXTENT OF THE MOISTURE PLUME...DUE TO MUCH WEAKER MID-
LEVEL FLOW...AND THIS WAS REMINISCENT OF THE GFS ENSEMBLE SUITE.
MUCH OF THE FORECAST WAS LEANED ON THIS 12Z ECMWF/GEFS SCENARIO.
HOWEVER...THE 00Z ECMWF IS NOW VERY SIMILAR TO THE GFS SOLUTION...
WHICH IS DISCONCERTING TO SAY THE LEAST.
POPS HAVE BEEN INCREASED AGAIN TO LIKELY ACROSS THE SOUTHERN HALF OF
THE AREA FOR TUESDAY. HOWEVER...WE WILL CONTINUE TO FEATURE VERY
CONSERVATIVE QPF NUMBERS UNTIL MORE CONFIDENCE CAN BE GLEANED FROM
MODEL SOLUTIONS. ANY PRECIPITATION IS EXPECTED TO END RATHER QUICKLY
TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 315 AM SUNDAY...COOL/DRY HIGH PRESSURE IS EXPECTED TO SETTLE
IN BEHIND A COLD FRONT FOR MUCH OF THE MEDIUM RANGE. THIS WIL RESULT
IN A POP-LESS FORECAST WITH TEMPS EXPECTED TO AVERAGE AROUND NORMAL
THROUGH THE PERIOD.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
AT KCLT AND ELSEWHERE...DRY HIGH PRESSURE WILL REMAIN OVER THE AREA
THROUGH THE PERIOD. CALM TO LGT AND VRBL WINDS OVERNIGHT WILL BECOME
LGT SLY BY NOON SUNDAY. EXPECT SCT HIGH CLOUDS SUN AFTN.
OUTLOOK...VFR CONDITIONS UNDER HIGH PRESSURE WILL CONTINUE THROUGH
MONDAY. AREAS OF MORNING FOG WILL BE POSSIBLE...MAINLY AROUND RIVERS
AND LAKES NEAR KAVL AND KAND. A COLD FRONT IS EXPECTED TO MOVE IN ON
TUESDAY WITH CHC SHWRS AND CIG/VSBY RESTRICTIONS. THE FRONT SHOULD
MOVE EAST WED WITH VFR GRADUALLY RETURNING.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FROST ADVISORY UNTIL 8 AM EST THIS MORNING FOR GAZ028-029.
NC...FROST ADVISORY UNTIL 8 AM EST THIS MORNING FOR NCZ068>072-082.
SC...FROST ADVISORY UNTIL 8 AM EST THIS MORNING FOR SCZ008>014-019.
&&
$$
SYNOPSIS...JPT
NEAR TERM...RB
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...RB
000
FXUS62 KCAE 080805
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
305 AM EST SUN NOV 8 2009
.SYNOPSIS...
DRY HIGH PRESSURE EXTENDING INTO THE FORECAST AREA WILL CONTINUE TO
DOMINATE THROUGH MONDAY. A COLD FRONT ALONG WITH A SURGE OF TROPICAL
MOISTURE WILL AFFECT THE AREA MAINLY TUESDAY AND TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
DRY HIGH PRESSURE RIDGING INTO THE FORECAST AREA WILL CONTINUE TO
DOMINATE TODAY. USED THE COOLER TEMPERATURE GUIDANCE BECAUSE OF
VERIFICATION THE PAST FEW DAYS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
THE MODELS AGREED KEEPING DRY HIGH PRESSURE IN CONTROL TONIGHT
THROUGH MONDAY. THE GFS WAS FASTER MOVING MOISTURE AND SIGNIFICANT
ISENTROPIC LIFT INTO THE FORECAST AREA LATE MONDAY NIGHT COMPARED
TO THE NAM. THE MAV MOS INDICATED CATEGORICAL POPS MONDAY NIGHT. THE
MET MOS WAS MUCH LOWER. KEPT POPS LESS THAN 20 PERCENT THROUGH
MONDAY WITH CHANCE POPS MONDAY NIGHT. THE CHANCE POPS MONDAY NIGHT
WERE AN AVERAGE OF THE MAV AND MET MOS. STRONG RADIATIONAL COOLING
SUPPORTED THE COOLER GUIDANCE TEMPERATURES TONIGHT. USED THE
GUIDANCE CONSENSUS FOR THE REST OF THE TEMPERATURE FORECAST.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE MAIN FORECAST PROBLEM IS THE IMPACT OF TROPICAL MOISTURE
ASSOCIATED WITH IDA. CONFIDENCE IS LOW BECAUSE OF MODEL
INCONSISTENCY. THE GFS SHOWED DEEP MOISTURE AND STRONG ISENTROPIC
LIFT TUESDAY. IT INDICATED H85 WINDS NEAR 45 KNOTS WITH AN
INVERTED SURFACE TROUGH EXTENDING THROUGH THE FORECAST AREA. THIS
SUPPORTED A SEVERE THUNDERSTORM AND FLOOD THREAT. THE NAM WAS
SLOWER AND SHOWED LESS ISENTROPIC LIFT AND DEEPER MOISTURE
SUPPRESSED FARTHER SOUTH. THE 12Z SATURDAY ECMWF WAS CLOSER TO
THE NAM. THE 00Z SUNDAY ECMWF WAS CLOSER TO THE GFS WITH RESPECT
TO SPREADING THE DEEP MOISTURE NORTHWARD...BUT WAS SLOWER. BELIEVE
THE BEST FORECAST FOR NOW IS TO ADJUST POPS UPWARD SLIGHTLY BASED
ON THE ECMWF TREND WITH POPS LIKELY TUESDAY AND TUESDAY NIGHT.
THE MODELS ARE IN GOOD AGREEMENT SHOWING DRY HIGH PRESSURE
DOMINATING THURSDAY THROUGH SATURDAY.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
MVFR TO IFR CONDITIONS POSSIBLE IN EARLY MORNING FOG...OTHERWISE
VFR CONDITIONS WILL PREVAIL. DRY HIGH PRESSURE AND LIGHT AND
VARIABLE WINDS WILL REMAIN IN PLACE THROUGH THE TAF PERIOD. STRONG
INVERSION ALREADY SET UP WITH FOG DEVELOPING AT AGS AND OGB. WILL
INCLUDE PREVAILING FOG CONDITIONS AT AGS/OGB AND TEMPO ELSEWHERE
THROUGH 12-13Z. FOG WILL RAPIDLY BURN OFF WITH SUNRISE AND THE
REMAINDER OF THE TAF PERIOD WILL BE VFR.
EXTENDED AVIATION OUTLOOK...WIDESPREAD CEILING AND VISIBILITY
RESTRICTIONS MAY OCCUR TUESDAY INTO WEDNESDAY ASSOCIATED WITH
ISENTROPIC LIFT.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...FROST ADVISORY UNTIL 7 AM EST THIS MORNING FOR SCZ015-016-
020>022.
GA...NONE.
&&
$$
SYNOPSIS...JL
NEAR TERM...JL
SHORT TERM...JL
LONG TERM...JL
AVIATION...MP
000
FXUS62 KCAE 080559
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1259 AM EST SUN NOV 8 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN IN CONTROL OF THE REGION THROUGH EARLY
NEXT WEEK. A COLD FRONT ALONG WITH A SURGE OF TROPICAL MOISTURE
WILL AFFECT THE AREA LATE MONDAY INTO TUESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
HIGH PRESSURE CENTERED OVER THE MID-ATLANTIC STATES WILL CONTINUE
TO DOMINATE THE REGION WITH CLEAR SKIES AND LIGHT WINDS TONIGHT.
WITH FORECAST LOWS IN THE MID 30S...WILL ISSUE A FROST ADVISORY
FOR THE NORTHERN MIDLANDS LATE TONIGHT. SOME PATCHY FROST POSSIBLE
IN A FEW OTHER LOCATIONS SUCH AS THE CSRA...BUT NOT ENOUGH TO
WARRANT AN ADVISORY SO WILL JUST ADVERTISE IN THE ZFP. OVERNIGHT
LOWS GENERALLY RANGING FROM THE MID 30S TO NEAR 40 DEGREES.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
DRY WEATHER WILL PERSIST SUNDAY INTO EARLY MONDAY AS THE HIGH
PRESSURE CENTER MOVES OFFSHORE. TEMPERATURES WILL MODERATE A BIT
EACH DAY SO FORECAST TEMPS CLOSE TO MODEL CONSENSUS. CLOUDS WILL
INCREASE MONDAY AHEAD OF AN APPROACHING COLD FRONT TO THE WEST
ALONG WITH TROPICAL MOISTURE FROM THE SOUTH ASSOCIATED WITH T.S.
IDA. STILL SOME QUESTION AS TO THE FUTURE TRACK OF IDA...BUT
MOISTURE AHEAD TO THE SYSTEM SHOULD SPREAD FROM THE NORTHERN GULF
OF MEXICO INTO GA/SC BY LATE MONDAY NIGHT. WILL INCREASE POPS TO
THE CHANCE CATEGORY FOR MONDAY NIGHT.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS MENTIONED EARLIER...STILL SOME QUESTION CONCERNING THE FUTURE
PATH OF T.S. IDA...BUT MODELS SEEM TO INDICATE THAT THE BEST
MOISTURE SURGE ASSOCIATED WITH IDA WILL BE ON TUESDAY. WILL GO
WITH HIGH CHANCE POPS FOR MUCH OF THE AREA...POSSIBLY LIKELY POPS
ACROSS THE CSRA. A COLD FRONT WILL ALSO APPROACH FROM THE WEST BY
LATE TUESDAY. DRY HIGH PRESSURE WILL BUILD IN FROM THE WEST LATE
WEDNESDAY THROUGH FRIDAY. ANOTHER COLD FRONT APPROACHES BY LATE
SATURDAY SO WILL INCLUDE A SLIGHT CHANCE POP BY THEN. FORECAST
TEMPS CLOSE TO MEX GUIDANCE.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
MVFR TO IFR CONDITIONS POSSIBLE IN EARLY MORNING FOG...OTHERWISE
VFR CONDITIONS WILL PREVAIL. DRY HIGH PRESSURE AND LIGHT AND
VARIABLE WINDS WILL REMAIN IN PLACE THROUGH THE TAF PERIOD. STRONG
INVERSION ALREADY SET UP WITH FOG DEVELOPING AT AGS AND OGB. WILL
INCLUDE PREVAILING FOG CONDITIONS AT AGS/OGB AND TEMPO ELSEWHERE
THROUGH 12-13Z. FOG WILL RAPIDLY BURN OFF WITH SUNRISE AND THE
REMAINDER OF THE TAF PERIOD WILL BE VFR.
EXTENDED AVIATION OUTLOOK...WIDESPREAD CEILING AND VISIBILITY
RESTRICTIONS MAY OCCUR TUESDAY INTO WEDNESDAY ASSOCIATED WITH
ISENTROPIC LIFT.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...FROST ADVISORY UNTIL 7 AM EST THIS MORNING FOR SCZ015-016-
020>022.
GA...NONE.
&&
$$
000
FXUS62 KCHS 080541
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1241 AM EST SUN NOV 8 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE
WEEKEND. THE COMBINATION OF TROPICAL CYCLONE IDA...OR ITS REMNANTS...
LIFTING NORTHWARD THROUGH THE GULF OF MEXICO AND A COLD FRONT
APPROACHING FROM THE NORTHWEST WILL KEEP THINGS UNSETTLED DURING
THE EARLY TO MIDDLE PART OF NEXT WEEK. HIGH PRESSURE WILL THEN
BUILD BACK INTO THE REGION BY THURSDAY AND REMAIN THE DOMINANT
WEATHER FEATURE THROUGH THE FIRST PART OF THE UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
SURFACE HIGH PRES EXTENDS E-W OVER OUR FORECAST AREA THIS EVENING.
SKIES ARE CLEAR AND WINDS ARE CALM. CONDITIONS ARE QUITE FAVORABLE
FOR STRONG RADIATIONAL COOLING. PATCHY FROST SEEMS LIKELY OVER
LOCATIONS ADJACENT TO THE CSRA AND SE MIDLANDS REGIONS. THE
GREATEST FROST POTENTIAL WILL OCCUR ROUGHLY N OF A PERKINS-
HILLTONIA-CROCKETVILLE-SMOAKS LINE. WE BELIEVE THAT FROST SHOULD
BE RELATIVELY PATCHY...ALTHOUGH WE WOULD NOT BE TOO SURPRISED TO
SEE ISOLATED LOCATIONS SUCH AS ALLENDALE BRIEFLY REACH 35-36
DEGREES TOWARD DAWN...SUGGESTING A VERY LOCALIZED POTENTIAL FOR
SLIGHTLY GREAT FROST COVERAGE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM MONDAY/...
HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT WILL HOLD OVER THE
REGION SUNDAY. TROPICAL CYCLONE IDA OVER THE WESTERN CARIBBEAN IS
FORECAST BY NHC TO MOVE THROUGH THE YUCATAN CHANNEL SUNDAY
AFTERNOON. THE GRADIENT BETWEEN THE HIGH TO THE NORTH AND IDA WILL
BEGIN TO TIGHTEN SUNDAY AFTERNOON BUT WINDS LOOK TO GO NO HIGHER
THAN 10-15 MPH. A WEAK AND DIFFUSE COASTAL TROUGH OFFSHORE WILL
BECOME ABSORBED THE THE SYNOPTIC EASTERLY FLOW DURING THIS TIME
AND WILL HAVE LITTLE IF ANY SIGNIFICANT IMPACT ON ANY SENSIBLE
WEATHER ELEMENTS AS IT DISSIPATES. SLIGHTLY HIGHER DEWPOINTS COULD
SUPPORT A BIT MORE IN THE WAY OF SHALLOW CUMULUS FROM LATE MORNING
THROUGH THE MID AFTERNOON HOURS...BUT STILL EXPECT SUNNY TO MOSTLY
SUNNY SKIES TO PREVAIL WITH A FEW HOURS OF PARTLY CLOUDY CONDITIONS
POSSIBLE ALONG THE I-95 CORRIDOR FROM SAVANNAH SOUTH. HIGHS WILL
REACH IN THE MID-UPPER 70S PER LOW-LEVEL THICKNESS PROGS EXCEPT
AT THE BEACHES WHERE CONSIDERABLY COOLER CONDITIONS WILL BE FOUND.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
MEDIUM RANGE GUIDANCE IS IN DECENT AGREEMENT THROUGHOUT THE EXTENDED
PERIODS THIS AFTERNOON...WITH SOME DIFFERENCES NOTED WITH RESPECT TO
THE EVOLUTION OF TROPICAL CYCLONE IDA OR THE REMNANTS OF THE SYSTEM
DURING THE EARLY TO MID WEEK TIME FRAME.
AN UPPER TROUGH MOVING THROUGH THE SOUTHERN PLAINS INTO THE LOWER
MISSISSIPPI VALLEY IN COMBINATION WITH DEEP LAYER RIDGING OVER THE
WESTERN ATLANTIC...WILL LIFT TROPICAL CYCLONE IDA OR THE REMNANTS OF
THE SYSTEM NORTHWARD THROUGH THE GULF OF MEXICO SUNDAY NIGHT THROUGH
TUESDAY. INITIALLY THE DRY AIRMASS IN PLACE...LACK OF ANY DEEP
MOISTURE AND ANY SIGNIFICANT FORCING FOR ASCENT...SHOULD PRECLUDE
MUCH IN THE WAY OF RAINFALL POTENTIAL. CAN/T RULE OUT A STRAY SHOWER
ROLLING IN OFF THE ATLANTIC MONDAY AFTERNOON...BUT FOR NOW WILL
CONTINUE WITH A RAIN FREE FORECAST SUNDAY NIGHT THROUGH MONDAY. DEEP
TROPICAL MOISTURE WILL STEADILY INCREASE ACROSS THE FORECAST AREA
TUESDAY...AND WITH BOTH ISENTROPIC ASCENT AND DYNAMIC FORCING
SWINGING INTO THE REGION...WILL CARRY LIKELY POPS ALL AREA.
A STRONG UPPER LEVEL TROUGH WILL THEN SHIFT EASTWARD THROUGH THE
EASTERN GREAT LAKES AND NEW ENGLAND STATES TUESDAY NIGHT...ALLOWING
A SURFACE COLD FRONT TO PUSH SOUTHEASTWARD THROUGH THE FORECAST
AREA. STRONG HIGH PRESSURE WILL BUILD NORTH OF THE REGION WEDNESDAY
THROUGH THURSDAY...BEFORE SHIFTING INTO THE WESTERN ATLANTIC FOR THE
TAIL END OF THE WORK WEEK AND INTO THE FIRST PART OF THE UPCOMING
WEEKEND. WILL CARRY LIKELY POPS TUESDAY NIGHT AS DEEP MOISTURE AND
FORCING WILL REMAIN IN PLACE ACROSS THE FORECAST AREA AS THE COLD
FRONT PUSHES SOUTHWARD THROUGH THE AREA. STILL SOME TIMING
DISCONTINUITIES IN THE MODELS WITH RESPECT TO HOW QUICKLY THE COLD
FRONT PUSHES THROUGH THE AREA...SO WILL KEEP CHANCE POPS GOING
THROUGH THE DAY WEDNESDAY. HIGH PRESSURE WILL BECOME MORE DOMINANT
WEDNESDAY NIGHT THROUGH SATURDAY...SO WILL MAINTAIN THE RAIN FREE
FORECAST. DEPENDING ON HOW THE POSITIONING OF THE RIDGE AXIS NORTH
OF THE REGION THURSDAY THROUGH SATURDAY...THERE IS A POTENTIAL FOR
SOME SHOWERS TO PUSH ONSHORE OFF THE ATLANTIC...BUT PROBABILITIES
APPEAR TOO LOW TO MENTION IN THE FORECAST AT THIS TIME.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL PREVAIL AT KCHS AND KSAV THROUGH 06Z MONDAY.
CLEAR SKIES AND CALM WINDS WILL PERSIST INTO MID-MORNING...
WITH AN EASTERLY FLOW DEVELOPING LATE THIS MORNING AND THIS
AFTERNOON WITH SPEEDS LESS THAN 10 KT. THE ONSHORE FLOW COULD
RESULT IN A FEW STRATOCUMULUS DEVELOPING DURING THE AFTERNOON NEAR
KSAV...OTHERWISE SOME INCREASING HIGH CLOUDINESS IS EXPECTED FROM
THE SOUTH TODAY INTO TONIGHT.
EXTENDED AVIATION OUTLOOK....VFR CONDITIONS WILL PREVAIL THROUGH
MON. POTENTIAL FOR MVFR OR IFR CONDITIONS MON NIGHT THROUGH WED.
LLWS ALSO POSSIBLE WED MORNING. VFR CONDITIONS EXPECTED WED NIGHT
INTO THU.
&&
.MARINE...
NORTHEAST WINDS WILL INCREASE TO 10-15 TONIGHT ACROSS MUCH OF OUR
MARINE AREA AS THE GRADIENT TIGHTENS BETWEEN HIGH PRES INLAND AND
A WEAK COASTAL TROUGH DEVELOPING OFFSHORE. SEAS 2 TO 3 FT NEAR
SHORE...BUILDING TO 3-4 FT OFFSHORE.
NORTHEAST WINDS WILL CONTINUE INTO SUNDAY BUT COULD LOCALLY VEER
EASTERLY NEAR THE COAST AS A RESULTANT SEA BREEZE CIRCULATION
DEVELOPS. SPEEDS OF 10-15 KT WILL PERSIST WITH SEAS WILL BUILD TO
2-4 FT NEARSHORE WATERS AND 4-5 FT OFFSHORE WATERS.
SUNDAY NIGHT THROUGH THURSDAY...HIGH PRESSURE OVER THE WESTERN
ATLANTIC IN COMBINATION WITH TROPICAL CYCLONE IDA OR THE REMNANTS
OF THE SYSTEM TRACKING NORTHWARD THROUGH THE GULF OF MEXICO...WILL
RESULT IN AN INCREASING GRADIENT ACROSS THE COASTAL WATERS SUNDAY
NIGHT THROUGH TUESDAY. A STRONG COLD FRONT WILL MOVE THROUGH THE
REGION TUESDAY NIGHT...WITH A POTENTIALLY SIGNIFICANT SURGE IN THE
WINDS BEHIND THE SYSTEM THROUGH THURSDAY AS A STRONG RIDGE OF HIGH
PRESSURE BUILDS NORTH OF THE REGION. SMALL CRAFT CONDITIONS FOR
WINDS/SEAS OR A COMBINATION OF THE TWO MAY DEVELOP AS EARLY AS
SUNDAY NIGHT ACROSS THE OUTER GEORGIA WATERS...WITH SMALL CRAFT
CONDITIONS EXPECTED TO MOVE INTO THE NEARSHORE WATERS MONDAY OR
MONDAY NIGHT. SMALL CRAFT CONDITIONS ARE THEN EXPECTED TO CONTINUE
FOR ALL WATERS WITH THE EXCEPTION OF CHARLESTON HARBOR THROUGH
THURSDAY. HEADLINE THRESHOLDS MAY NOT BE REACHED IN CHARLESTON
HARBOR THROUGH TUESDAY...BUT SMALL CRAFT CONDITIONS APPEAR FAIRLY
LIKELY TUESDAY NIGHT THROUGH WEDNESDAY NIGHT AS THE STRONG WIND
SURGE DEVELOPS BEHIND THE COLD FRONTAL PASSAGE. IN FACT DEPENDING
ON THE POSITIONING AND STRENGTH OF HIGH PRESSURE TO THE NORTH AND
THE TROPICAL OR SUBTROPICAL SYSTEM TO THE SOUTH...GALE CONDITIONS
MAY BE REACHED ACROSS PORTIONS OF THE WATERS IN THE TUESDAY NIGHT
THROUGH WEDNESDAY NIGHT TIME FRAME.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
000
FXUS62 KGSP 080505
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1205 AM EST SUN NOV 8 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
ABUNDANT MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS EXPECTED TO
MOVE INTO THE CAROLINAS AND NORTH GEORGIA AHEAD OF A COLD FRONT ON
TUESDAY...WITH THE FRONT EXPECTED TO CROSS THE AREA LATE TUESDAY
INTO EARLY WEDNESDAY. HIGH PRESSURE WILL THEN RETURN FOR THE LATER
HALF OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
A DRY RIDGE WILL REMAIN IN PLACE OVER THE FORECAST AREA TONIGHT.
CLEAR SKIES AND LIGHT WINDS WILL PERMIT EXCELLENT RADIATING
CONDITIONS...HOWEVER...TEMPS REMAIN AT OR SLIGHTLY ABOVE THE LATEST
LAPS GUIDANCE AT THIS HOUR. WINDS WILL CONTINUE TO DIMINISH
OVERNIGHT AND THIS SHOULD ALLOW FROST FORMATION IN THE CURRENT
ADVISORY AREA...SO NO ADJUSTMENTS TO THE NPW ARE NEEDED. MINOR
TWEAKS TO RAISE RIDGE TOP TEMPS AND SLIGHTLY LOWER VALLEY TEMPS HAVE
BEEN MADE.
THE UPPER RIDGE WILL STRENGTHEN FURTHER SUNDAY. THICKNESSES WILL
INCREASE AND LIGHT SLY WINDS WITH FULL SUN WILL PRODUCE TEMPERATURES
ABOUT 10 DEGREES ABOVE NORMAL FOR THIS TIME OF YEAR.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
AS OF 230 PM EDT SATURDAY...A WELL AMPLIFIED UPPER RIDGE OVER THE
SOUTHEAST ON SUNDAY NIGHT WILL MOVE OFF THE EAST COAST ON MONDAY
NIGHT. THE UPPER TROUGH IN ITS WAKE WILL PROGRESS TO THE
APPALACHIANS ON TUESDAY...WHEN A WELL DEFINED SOUTHERN STREAM
SHORTWAVE IN ITS BASE WILL CROSS OUR AREA. DRY HIGH PRESSURE WILL
PERSIST OVER THE MID ATLANTIC COAST SUNDAY NIGHT AND MONDAY. ON
MONDAY NIGHT THE GFS SHOWS GULF MOISTURE ASSOCIATED WITH TROPICAL
SYSTEM IDA MOVING INTO GA AND THE WESTERN CAROLINAS...WITH THE
SURFACE PRESSURE GRADIENT TIGHTENING OVER THE SAVANNAH RIVER VALLEY.
THE TPC FORECAST FOR IDA SHOWS IT REMAINING IN THE NORTHEAST GULF
INTO TUESDAY...SO CONFIDENCE ON MOISTURE OVER OUR AREA IS NOT HIGH.
NEVERTHELESS...WITH ISENTROPIC UPGLIDE AND A MOIST UPSLOPE COMPONENT
EXPECTED...THE FORECAST WILL SHOW INCREASING CLOUD COVER AND A
CHANCE OF PRECIPITATION TUESDAY AND TUESDAY NIGHT...BEFORE A COLD
FRONT SWEEPS ACROSS THE AREA FROM THE NORTHWEST LATE TUESDAY NIGHT.
MAXIMUMS TEMPERATURES WILL EXPERIENCE A DOWNWARD TREND AS HEIGHTS
FALL ALOFT AND CLOUD COVER INCREASES. MINIMUM TEMPERATURES WILL RISE
WITH THE INCREASE IN CLOUD COVER AND LOW LEVEL MOISTURE...THEN DROP
OFF TUESDAY NIGHT BEHIND THE FRONT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 200 PM SATURDAY...THE EXTENDED PERIOD STARTS WITH AN EXITING
LOW PRES SYSTEM TO OUR EAST...WITH DECENT LLVL CAA AND DOWNSLOPE
FLOW ACRS THE CWFA. DRY CP AIR MASS PUSHES INTO THE AREA FROM LATE
WED THRU FRIDAY UNDER CONFLUENT FLOW DOWNSTREAM OF SPLIT WRN NOAM
FLOW. SO EXPECT TEMPS AT OR SLIGHTLY BELOW NORMAL UNDER MOSTLY CLEAR
SKIES FOR WED AND THU.
FRIDAY INTO NEXT WEEKEND...GUIDANCE IN DECENT AGREEMENT ON SFC HI
PRES SHIFTING EAST OFF THE COAST...AS UPR LVL ENERGY BEGINS TO
ADVANCE EAST INTO THE GREAT PLAINS. FOR NOW...JUST ADDED A SLGT CHC
POP FOR SATURDAY WITH INCREASING CLOUDS AND A WARMING TREND.
&&
.AVIATION /05Z SUNDAY THROUGH THURSDAY/...
AT KCLT AND ELSEWHERE...DRY HIGH PRESSURE WILL REMAIN OVER THE AREA
THROUGH THE PERIOD. CALM TO LGT AND VRBL WINDS OVERNIGHT WILL BECOME
LGT SLY BY NOON SUNDAY. EXPECT SCT HIGH CLOUDS SUN AFTN.
OUTLOOK...VFR CONDITIONS UNDER HIGH PRESSURE WILL CONTINUE THROUGH
MONDAY. AREAS OF MORNING FOG WILL BE POSSIBLE...MAINLY AROUND RIVERS
AND LAKES NEAR KAVL AND KAND. A COLD FRONT IS EXPECTED TO MOVE IN ON
TUESDAY WITH CHC SHWRS AND CIG/VSBY RESTRICTIONS. THE FRONT SHOULD
MOVE EAST WED WITH VFR GRADUALLY RETURNING.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FROST ADVISORY FROM 4 AM TO 8 AM EST THIS MORNING FOR GAZ028-
029.
NC...FROST ADVISORY FROM 4 AM TO 8 AM EST THIS MORNING FOR
NCZ068>072-082.
SC...FROST ADVISORY FROM 4 AM TO 8 AM EST THIS MORNING FOR
SCZ008>014-019.
&&
$$
SYNOPSIS...JPT
NEAR TERM...HG
SHORT TERM...JAT
LONG TERM...ARK
AVIATION...RB
000
FXUS62 KGSP 080232
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
932 PM EST SAT NOV 7 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
ABUNDANT MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS EXPECTED TO
MOVE INTO THE CAROLINAS AND NORTH GEORGIA AHEAD OF A COLD FRONT ON
TUESDAY...WITH THE FRONT EXPECTED TO CROSS THE AREA LATE TUESDAY
INTO EARLY WEDNESDAY. HIGH PRESSURE WILL THEN RETURN FOR THE LATER
HALF OF NEXT WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
A DRY RIDGE WILL REMAIN IN PLACE OVER THE FORECAST AREA TONIGHT.
CLEAR SKIES AND LIGHT WINDS WILL PERMIT EXCELLENT RADIATING
CONDITIONS...HOWEVER...TEMPS REMAIN AT OR SLIGHTLY ABOVE THE LATEST
LAPS GUIDANCE AT THIS HOUR. WINDS WILL CONTINUE TO DIMINISH
OVERNIGHT AND THIS SHOULD ALLOW FROST FORMATION IN THE CURRENT
ADVISORY AREA...SO NO ADJUSTMENTS TO THE NPW ARE NEEDED. MINOR
TWEAKS TO RAISE RIDGE TOP TEMPS AND SLIGHTLY LOWER VALLEY TEMPS HAVE
BEEN MADE.
THE UPPER RIDGE WILL STRENGTHEN FURTHER SUNDAY. THICKNESSES WILL
INCREASE AND LIGHT SLY WINDS WITH FULL SUN WILL PRODUCE TEMPERATURES
ABOUT 10 DEGREES ABOVE NORMAL FOR THIS TIME OF YEAR.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
AS OF 230 PM EDT SATURDAY...A WELL AMPLIFIED UPPER RIDGE OVER THE
SOUTHEAST ON SUNDAY NIGHT WILL MOVE OFF THE EAST COAST ON MONDAY
NIGHT. THE UPPER TROUGH IN ITS WAKE WILL PROGRESS TO THE
APPALACHIANS ON TUESDAY...WHEN A WELL DEFINED SOUTHERN STREAM
SHORTWAVE IN ITS BASE WILL CROSS OUR AREA. DRY HIGH PRESSURE WILL
PERSIST OVER THE MID ATLANTIC COAST SUNDAY NIGHT AND MONDAY. ON
MONDAY NIGHT THE GFS SHOWS GULF MOISTURE ASSOCIATED WITH TROPICAL
SYSTEM IDA MOVING INTO GA AND THE WESTERN CAROLINAS...WITH THE
SURFACE PRESSURE GRADIENT TIGHTENING OVER THE SAVANNAH RIVER VALLEY.
THE TPC FORECAST FOR IDA SHOWS IT REMAINING IN THE NORTHEAST GULF
INTO TUESDAY...SO CONFIDENCE ON MOISTURE OVER OUR AREA IS NOT HIGH.
NEVERTHELESS...WITH ISENTROPIC UPGLIDE AND A MOIST UPSLOPE COMPONENT
EXPECTED...THE FORECAST WILL SHOW INCREASING CLOUD COVER AND A
CHANCE OF PRECIPITATION TUESDAY AND TUESDAY NIGHT...BEFORE A COLD
FRONT SWEEPS ACROSS THE AREA FROM THE NORTHWEST LATE TUESDAY NIGHT.
MAXIMUMS TEMPERATURES WILL EXPERIENCE A DOWNWARD TREND AS HEIGHTS
FALL ALOFT AND CLOUD COVER INCREASES. MINIMUM TEMPERATURES WILL RISE
WITH THE INCREASE IN CLOUD COVER AND LOW LEVEL MOISTURE...THEN DROP
OFF TUESDAY NIGHT BEHIND THE FRONT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 200 PM SATURDAY...THE EXTENDED PERIOD STARTS WITH AN EXITING
LOW PRES SYSTEM TO OUR EAST...WITH DECENT LLVL CAA AND DOWNSLOPE
FLOW ACRS THE CWFA. DRY CP AIR MASS PUSHES INTO THE AREA FROM LATE
WED THRU FRIDAY UNDER CONFLUENT FLOW DOWNSTREAM OF SPLIT WRN NOAM
FLOW. SO EXPECT TEMPS AT OR SLIGHTLY BELOW NORMAL UNDER MOSTLY CLEAR
SKIES FOR WED AND THU.
FRIDAY INTO NEXT WEEKEND...GUIDANCE IN DECENT AGREEMENT ON SFC HI
PRES SHIFTING EAST OFF THE COAST...AS UPR LVL ENERGY BEGINS TO
ADVANCE EAST INTO THE GREAT PLAINS. FOR NOW...JUST ADDED A SLGT CHC
POP FOR SATURDAY WITH INCREASING CLOUDS AND A WARMING TREND.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
AT KCLT AND ELSEWHERE...DRY HIGH PRESSURE WILL PERSIST OVER THE
TERMINAL FORECAST AREA THROUGH THE PERIOD. LIGHT SOUTHERLY WINDS
THIS EVENING WILL BECOME VARIABLE OVERNIGHT...WITH A LIGHT NORTHERLY
COMPONENT POSSIBLE AT TIMES...BEFORE RETURNING TO PREDOMINANT LIGHT
SOUTH OR SOUTHEAST FLOW BY NOON SUNDAY. MOS REMAINS MIXED ON FOG
POTENTIAL LATE TONIGHT AT KAVL AND KAND...BUT MODEL PROFILES DO NOT
APPEAR SUPPORTIVE OF AN MVFR FOG MENTION AT PRESENT. WILL CONTINUE
VFR TAFS OVERNIGHT. A FEW HIGH CLOUDS MAY APPEAR FROM THE S SUNDAY
AFTERNOON.
OUTLOOK...VFR CONDITIONS UNDER HIGH PRESSURE WILL CONTINUE THROUGH
MONDAY. AREAS OF MORNING FOG WILL BE POSSIBLE...MAINLY AROUND RIVERS
AND LAKES NEAR KAVL AND KAND. A COLD FRONT IS EXPECTED TO MOVE IN ON
TUESDAY WITH A CHC SHWRS AND CIG/VSBY RESTRICTIONS. THE FRONT SHOULD
MOVE EAST WED WITH VFR GRADUALLY RETURNING.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FROST ADVISORY FROM 4 AM TO 8 AM EST SUNDAY FOR GAZ028-029.
NC...FROST ADVISORY FROM 4 AM TO 8 AM EST SUNDAY FOR NCZ068>072-082.
SC...FROST ADVISORY FROM 4 AM TO 8 AM EST SUNDAY FOR SCZ008>014-019.
&&
$$
SYNOPSIS...JPT
NEAR TERM...HG
SHORT TERM...JAT
LONG TERM...ARK
AVIATION...HG
000
FXUS62 KCHS 080223
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
923 PM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE
WEEKEND. THE COMBINATION OF TROPICAL CYCLONE IDA...OR ITS REMNANTS...
LIFTING NORTHWARD THROUGH THE GULF OF MEXICO AND A COLD FRONT
APPROACHING FROM THE NORTHWEST WILL KEEP THINGS UNSETTLED DURING
THE EARLY TO MIDDLE PART OF NEXT WEEK. HIGH PRESSURE WILL THEN
BUILD BACK INTO THE REGION BY THURSDAY AND REMAIN THE DOMINANT
WEATHER FEATURE THROUGH THE FIRST PART OF THE UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
SURFACE HIGH PRES EXTENDS E-W OVER OUR FORECAST AREA THIS EVENING.
SKIES ARE CLEAR AND WINDS ARE CALM. CONDITIONS ARE QUITE FAVORABLE
FOR STRONG RADIATIONAL COOLING. PATCHY FROST SEEMS LIKELY OVER
LOCATIONS ADJACENT TO THE CSRA AND SE MIDLANDS REGIONS. THE
GREATEST FROST POTENTIAL WILL OCCUR ROUGHLY N OF A PERKINS-
HILLTONIA-CROCKETVILLE-SMOAKS LINE. WE BELIEVE THAT FROST SHOULD
BE RELATIVELY PATCHY...ALTHOUGH WE WOULD NOT BE TOO SURPRISED TO
SEE ISOLATED LOCATIONS SUCH AS ALLENDALE BRIEFLY REACH 35-36
DEGREES TOWARD DAWN...SUGGESTING A VERY LOCALIZED POTENTIAL FOR
SLIGHTLY GREAT FROST COVERAGE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT WILL HOLD OVER THE
REGION SUNDAY. TROPICAL CYCLONE IDA OVER THE WESTERN CARIBBEAN IS
FORECAST BY NHC TO MOVE THROUGH THE YUCATAN CHANNEL SUNDAY
AFTERNOON. THE GRADIENT BETWEEN THE HIGH TO THE NORTH AND IDA WILL
BEGIN TO TIGHTEN SUNDAY AFTERNOON BUT WINDS LOOK TO GO NO HIGHER
THAN 10-15 MPH. A WEAK AND DIFFUSE COASTAL TROUGH OFFSHORE WILL
BECOME ABSORBED THE THE SYNOPTIC EASTERLY FLOW DURING THIS TIME
AND WILL HAVE LITTLE IF ANY SIGNIFICANT IMPACT ON ANY SENSIBLE
WEATHER ELEMENTS AS IT DISSIPATES. SLIGHTLY HIGHER DEWPOINTS COULD
SUPPORT A BIT MORE IN THE WAY OF SHALLOW CUMULUS FROM LATE MORNING
THROUGH THE MID AFTERNOON HOURS...BUT STILL EXPECT SUNNY TO MOSTLY
SUNNY SKIES TO PREVAIL WITH A FEW HOURS OF PARTLY CLOUDY CONDITIONS
POSSIBLE ALONG THE I-95 CORRIDOR FROM SAVANNAH SOUTH. HIGHS WILL
REACH IN THE MID-UPPER 70S PER LOW-LEVEL THICKNESS PROGS EXCEPT
AT THE BEACHES WHERE CONSIDERABLY COOLER CONDITIONS WILL BE FOUND.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
MEDIUM RANGE GUIDANCE IS IN DECENT AGREEMENT THROUGHOUT THE EXTENDED
PERIODS THIS AFTERNOON...WITH SOME DIFFERENCES NOTED WITH RESPECT TO
THE EVOLUTION OF TROPICAL CYCLONE IDA OR THE REMNANTS OF THE SYSTEM
DURING THE EARLY TO MID WEEK TIME FRAME.
AN UPPER TROUGH MOVING THROUGH THE SOUTHERN PLAINS INTO THE LOWER
MISSISSIPPI VALLEY IN COMBINATION WITH DEEP LAYER RIDGING OVER THE
WESTERN ATLANTIC...WILL LIFT TROPICAL CYCLONE IDA OR THE REMNANTS OF
THE SYSTEM NORTHWARD THROUGH THE GULF OF MEXICO SUNDAY NIGHT THROUGH
TUESDAY. INITIALLY THE DRY AIRMASS IN PLACE...LACK OF ANY DEEP
MOISTURE AND ANY SIGNIFICANT FORCING FOR ASCENT...SHOULD PRECLUDE
MUCH IN THE WAY OF RAINFALL POTENTIAL. CAN/T RULE OUT A STRAY SHOWER
ROLLING IN OFF THE ATLANTIC MONDAY AFTERNOON...BUT FOR NOW WILL
CONTINUE WITH A RAIN FREE FORECAST SUNDAY NIGHT THROUGH MONDAY. DEEP
TROPICAL MOISTURE WILL STEADILY INCREASE ACROSS THE FORECAST AREA
TUESDAY...AND WITH BOTH ISENTROPIC ASCENT AND DYNAMIC FORCING
SWINGING INTO THE REGION...WILL CARRY LIKELY POPS ALL AREA.
A STRONG UPPER LEVEL TROUGH WILL THEN SHIFT EASTWARD THROUGH THE
EASTERN GREAT LAKES AND NEW ENGLAND STATES TUESDAY NIGHT...ALLOWING
A SURFACE COLD FRONT TO PUSH SOUTHEASTWARD THROUGH THE FORECAST
AREA. STRONG HIGH PRESSURE WILL BUILD NORTH OF THE REGION WEDNESDAY
THROUGH THURSDAY...BEFORE SHIFTING INTO THE WESTERN ATLANTIC FOR THE
TAIL END OF THE WORK WEEK AND INTO THE FIRST PART OF THE UPCOMING
WEEKEND. WILL CARRY LIKELY POPS TUESDAY NIGHT AS DEEP MOISTURE AND
FORCING WILL REMAIN IN PLACE ACROSS THE FORECAST AREA AS THE COLD
FRONT PUSHES SOUTHWARD THROUGH THE AREA. STILL SOME TIMING
DISCONTINUITIES IN THE MODELS WITH RESPECT TO HOW QUICKLY THE COLD
FRONT PUSHES THROUGH THE AREA...SO WILL KEEP CHANCE POPS GOING
THROUGH THE DAY WEDNESDAY. HIGH PRESSURE WILL BECOME MORE DOMINANT
WEDNESDAY NIGHT THROUGH SATURDAY...SO WILL MAINTAIN THE RAIN FREE
FORECAST. DEPENDING ON HOW THE POSITIONING OF THE RIDGE AXIS NORTH
OF THE REGION THURSDAY THROUGH SATURDAY...THERE IS A POTENTIAL FOR
SOME SHOWERS TO PUSH ONSHORE OFF THE ATLANTIC...BUT PROBABILITIES
APPEAR TOO LOW TO MENTION IN THE FORECAST AT THIS TIME.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL PERSIST AT BOTH CHS AND SAV TERMINALS THROUGH
00Z MONDAY. CLEAR SKIES WILL LEAD TO STRONG RADIATIONAL COOLING
OVERNIGHT AND RESULT IN CALM WINDS AT BOTH TERMINALS. NORTHEAST
WINDS BETWEEN 5 TO 10 KNOTS WILL DEVELOP LATE SUNDAY MORNING THEN
VEER TO AN EASTERLY FLOW SUNDAY AFTERNOON. ONSHORE FLOW IS EXPECTED
TO CONTRIBUTE TO A FEW CUMULUS DEVELOPING SUNDAY AFTERNOON.
EXTENDED AVIATION OUTLOOK....VFR CONDITIONS WILL PREVAIL THROUGH
MON. POTENTIAL FOR MVFR OR IFR CONDITIONS MON NIGHT THROUGH WED.
LLWS ALSO POSSIBLE WED MORNING. VFR CONDITIONS EXPECTED WED NIGHT
INTO THU.
&&
.MARINE...
NORTHEAST WINDS WILL INCREASE TO 10-15 TONIGHT ACROSS MUCH OF OUR
MARINE AREA AS THE GRADIENT TIGHTENS BETWEEN HIGH PRES INLAND AND
A WEAK COASTAL TROUGH DEVELOPING OFFSHORE. SEAS 2 TO 3 FT NEAR
SHORE...BUILDING TO 3-4 FT OFFSHORE.
NORTHEAST WINDS WILL CONTINUE INTO SUNDAY BUT COULD LOCALLY VEER
EASTERLY NEAR THE COAST AS A RESULTANT SEA BREEZE CIRCULATION
DEVELOPS. SPEEDS OF 10-15 KT WILL PERSIST WITH SEAS WILL BUILD TO
2-4 FT NEARSHORE WATERS AND 4-5 FT OFFSHORE WATERS.
SUNDAY NIGHT THROUGH THURSDAY...HIGH PRESSURE OVER THE WESTERN
ATLANTIC IN COMBINATION WITH TROPICAL CYCLONE IDA OR THE REMNANTS
OF THE SYSTEM TRACKING NORTHWARD THROUGH THE GULF OF MEXICO...WILL
RESULT IN AN INCREASING GRADIENT ACROSS THE COASTAL WATERS SUNDAY
NIGHT THROUGH TUESDAY. A STRONG COLD FRONT WILL MOVE THROUGH THE
REGION TUESDAY NIGHT...WITH A POTENTIALLY SIGNIFICANT SURGE IN THE
WINDS BEHIND THE SYSTEM THROUGH THURSDAY AS A STRONG RIDGE OF HIGH
PRESSURE BUILDS NORTH OF THE REGION. SMALL CRAFT CONDITIONS FOR
WINDS/SEAS OR A COMBINATION OF THE TWO MAY DEVELOP AS EARLY AS
SUNDAY NIGHT ACROSS THE OUTER GEORGIA WATERS...WITH SMALL CRAFT
CONDITIONS EXPECTED TO MOVE INTO THE NEARSHORE WATERS MONDAY OR
MONDAY NIGHT. SMALL CRAFT CONDITIONS ARE THEN EXPECTED TO CONTINUE
FOR ALL WATERS WITH THE EXCEPTION OF CHARLESTON HARBOR THROUGH
THURSDAY. HEADLINE THRESHOLDS MAY NOT BE REACHED IN CHARLESTON
HARBOR THROUGH TUESDAY...BUT SMALL CRAFT CONDITIONS APPEAR FAIRLY
LIKELY TUESDAY NIGHT THROUGH WEDNESDAY NIGHT AS THE STRONG WIND
SURGE DEVELOPS BEHIND THE COLD FRONTAL PASSAGE. IN FACT DEPENDING
ON THE POSITIONING AND STRENGTH OF HIGH PRESSURE TO THE NORTH AND
THE TROPICAL OR SUBTROPICAL SYSTEM TO THE SOUTH...GALE CONDITIONS
MAY BE REACHED ACROSS PORTIONS OF THE WATERS IN THE TUESDAY NIGHT
THROUGH WEDNESDAY NIGHT TIME FRAME.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
000
FXUS62 KCHS 072352
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
652 PM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE
WEEKEND. THE COMBINATION OF TROPICAL CYCLONE IDA...OR ITS REMNANTS...
LIFTING NORTHWARD THROUGH THE GULF OF MEXICO AND A COLD FRONT
APPROACHING FROM THE NORTHWEST WILL KEEP THINGS UNSETTLED DURING
THE EARLY TO MIDDLE PART OF NEXT WEEK. HIGH PRESSURE WILL THEN
BUILD BACK INTO THE REGION BY THURSDAY AND REMAIN THE DOMINANT
WEATHER FEATURE THROUGH THE FIRST PART OF THE UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
ELONGATED HIGH PRESSURE CENTERED OVER THE NORTH CAROLINA OUTER
BANKS THIS AFTERNOON WILL REMAIN ACROSS THE REGION TONIGHT. PATCHY
CUMULUS THAT HAS DEVELOPED OVER PARTS OF INLAND MCINTOSH COUNTY
WILL QUICKLY DISSIPATE OVER THE NEXT 1-2 HOURS AS SURFACE HEATING
WANES WITH THE APPROACH OF SUNSET. CLEAR SKIES AND CALM WINDS WILL
PROMOTE A STRONG RADIATIONAL SETUP AGAIN TONIGHT EXCEPT ALONG THE
IMMEDIATE COAST WHERE A RESIDUAL PRESSURE GRADIENT BETWEEN THE
INLAND SURFACE HIGH AND A WEAK COASTAL TROUGH FORMING OFFSHORE
WILL KEEP THE ATMOSPHERE A BIT MORE MIXED. EXPECT LOWS FROM THE
UPPER 30S WELL INLAND TO THE MID-UPPER 50S ALONG THE BEACHES.
THERE IS SOME CONCERN FOR SOME FROST FORMATION WELL INLAND TONIGHT
WHERE CO-OP TEMPERATURE GUIDANCE SUGGEST LOWS MAY DROP INTO THE
36-37 DEGREE RANGE IN A FEW SHELTERED POCKETS. THE GREATEST FROST
POTENTIAL WILL OCCUR ROUGHLY NORTH OF A PERKINS-HILLTONIA-
CROCKETVILLE-SMOAKS LINE BUT ATTM WE BELIEVE ANY FROST THAT FORMS
WILL BE FAIRLY PATCHY. WILL FORGO THE ISSUANCE OF A FROST ADVISORY
PER COORDINATION WITH WFO COLUMBIA...BUT THE EVENING SHIFT WILL
CAREFULLY MONITOR TRENDS AS ANY LOWERING OF TEMPERATURES IN THIS
AREA WILL NECESSITATE THE ISSUANCE OF AN ADVISORY.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT WILL HOLD OVER THE
REGION SUNDAY. TROPICAL CYCLONE IDA OVER THE WESTERN CARIBBEAN IS
FORECAST BY NHC TO MOVE THROUGH THE YUCATAN CHANNEL SUNDAY
AFTERNOON. THE GRADIENT BETWEEN THE HIGH TO THE NORTH AND IDA WILL
BEGIN TO TIGHTEN SUNDAY AFTERNOON BUT WINDS LOOK TO GO NO HIGHER
THAN 10-15 MPH. A WEAK AND DIFFUSE COASTAL TROUGH OFFSHORE WILL
BECOME ABSORBED THE THE SYNOPTIC EASTERLY FLOW DURING THIS TIME
AND WILL HAVE LITTLE IF ANY SIGNIFICANT IMPACT ON ANY SENSIBLE
WEATHER ELEMENTS AS IT DISSIPATES. SLIGHTLY HIGHER DEWPOINTS COULD
SUPPORT A BIT MORE IN THE WAY OF SHALLOW CUMULUS FROM LATE MORNING
THROUGH THE MID AFTERNOON HOURS...BUT STILL EXPECT SUNNY TO MOSTLY
SUNNY SKIES TO PREVAIL WITH A FEW HOURS OF PARTLY CLOUDY CONDITIONS
POSSIBLE ALONG THE I-95 CORRIDOR FROM SAVANNAH SOUTH. HIGHS WILL
REACH IN THE MID-UPPER 70S PER LOW-LEVEL THICKNESS PROGS EXCEPT
AT THE BEACHES WHERE CONSIDERABLY COOLER CONDITIONS WILL BE FOUND.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
MEDIUM RANGE GUIDANCE IS IN DECENT AGREEMENT THROUGHOUT THE EXTENDED
PERIODS THIS AFTERNOON...WITH SOME DIFFERENCES NOTED WITH RESPECT TO
THE EVOLUTION OF TROPICAL CYCLONE IDA OR THE REMNANTS OF THE SYSTEM
DURING THE EARLY TO MID WEEK TIME FRAME.
AN UPPER TROUGH MOVING THROUGH THE SOUTHERN PLAINS INTO THE LOWER
MISSISSIPPI VALLEY IN COMBINATION WITH DEEP LAYER RIDGING OVER THE
WESTERN ATLANTIC...WILL LIFT TROPICAL CYCLONE IDA OR THE REMNANTS OF
THE SYSTEM NORTHWARD THROUGH THE GULF OF MEXICO SUNDAY NIGHT THROUGH
TUESDAY. INITIALLY THE DRY AIRMASS IN PLACE...LACK OF ANY DEEP
MOISTURE AND ANY SIGNIFICANT FORCING FOR ASCENT...SHOULD PRECLUDE
MUCH IN THE WAY OF RAINFALL POTENTIAL. CAN/T RULE OUT A STRAY SHOWER
ROLLING IN OFF THE ATLANTIC MONDAY AFTERNOON...BUT FOR NOW WILL
CONTINUE WITH A RAIN FREE FORECAST SUNDAY NIGHT THROUGH MONDAY. DEEP
TROPICAL MOISTURE WILL STEADILY INCREASE ACROSS THE FORECAST AREA
TUESDAY...AND WITH BOTH ISENTROPIC ASCENT AND DYNAMIC FORCING
SWINGING INTO THE REGION...WILL CARRY LIKELY POPS ALL AREA.
A STRONG UPPER LEVEL TROUGH WILL THEN SHIFT EASTWARD THROUGH THE
EASTERN GREAT LAKES AND NEW ENGLAND STATES TUESDAY NIGHT...ALLOWING
A SURFACE COLD FRONT TO PUSH SOUTHEASTWARD THROUGH THE FORECAST
AREA. STRONG HIGH PRESSURE WILL BUILD NORTH OF THE REGION WEDNESDAY
THROUGH THURSDAY...BEFORE SHIFTING INTO THE WESTERN ATLANTIC FOR THE
TAIL END OF THE WORK WEEK AND INTO THE FIRST PART OF THE UPCOMING
WEEKEND. WILL CARRY LIKELY POPS TUESDAY NIGHT AS DEEP MOISTURE AND
FORCING WILL REMAIN IN PLACE ACROSS THE FORECAST AREA AS THE COLD
FRONT PUSHES SOUTHWARD THROUGH THE AREA. STILL SOME TIMING
DISCONTINUITIES IN THE MODELS WITH RESPECT TO HOW QUICKLY THE COLD
FRONT PUSHES THROUGH THE AREA...SO WILL KEEP CHANCE POPS GOING
THROUGH THE DAY WEDNESDAY. HIGH PRESSURE WILL BECOME MORE DOMINANT
WEDNESDAY NIGHT THROUGH SATURDAY...SO WILL MAINTAIN THE RAIN FREE
FORECAST. DEPENDING ON HOW THE POSITIONING OF THE RIDGE AXIS NORTH
OF THE REGION THURSDAY THROUGH SATURDAY...THERE IS A POTENTIAL FOR
SOME SHOWERS TO PUSH ONSHORE OFF THE ATLANTIC...BUT PROBABILITIES
APPEAR TOO LOW TO MENTION IN THE FORECAST AT THIS TIME.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL PERSIST AT BOTH CHS AND SAV TERMINALS THROUGH
00Z MONDAY. CLEAR SKIES WILL LEAD TO STRONG RADIATIONAL COOLING
OVERNIGHT AND RESULT IN CALM WINDS AT BOTH TERMINALS. NORTHEAST
WINDS BETWEEN 5 TO 10 KNOTS WILL DEVELOP LATE SUNDAY MORNING THEN
VEER TO AN EASTERLY FLOW SUNDAY AFTERNOON. ONSHORE FLOW IS EXPECTED
TO CONTRIBUTE TO A FEW CUMULUS DEVELOPING SUNDAY AFTERNOON.
EXTENDED AVIATION OUTLOOK....VFR CONDITIONS WILL PREVAIL THROUGH
MONDAY. THE COMBINATION OF A STORM SYSTEM LIFTING NORTHEAST
THROUGH THE GULF OF MEXICO AND A COLD FRONT APPROACHING FROM THE
NORTHWEST WILL RESULT IN UNSETTLED WEATHER AND THE POTENTIAL FOR
MVFR OR IFR CONDITIONS MONDAY NIGHT THROUGH WEDNESDAY. LLWS IS
ALSO POSSIBLE WEDNESDAY MORNING. VFR CONDITIONS ARE THEN EXPECTED
TO RETURN WEDNESDAY NIGHT AND THURSDAY.
&&
.MARINE...
NORTHEAST WINDS WILL INCREASE TO 10-15 TONIGHT ACROSS MOST OF THE
MARINE AREA AS THE GRADIENT TIGHTENS BETWEEN HIGH PRESSURE INLAND
AND A WEAK COASTAL TROUGH DEVELOPING OFFSHORE. SEAS 2 FT NEARSHORE
AND BUILDING TO 3-4 FT OFFSHORE.
NORTHEAST WINDS WILL CONTINUE INTO SUNDAY BUT COULD LOCALLY VEER
EASTERLY NEAR THE COAST AS A RESULTANT SEA BREEZE CIRCULATION
DEVELOPS. SPEEDS OF 10-15 KT WILL PERSIST WITH SEAS WILL BUILD TO
2-4 FT NEARSHORE WATERS AND 4-5 FT OFFSHORE WATERS.
SUNDAY NIGHT THROUGH THURSDAY...HIGH PRESSURE OVER THE WESTERN
ATLANTIC IN COMBINATION WITH TROPICAL CYCLONE IDA OR THE REMNANTS
OF THE SYSTEM TRACKING NORTHWARD THROUGH THE GULF OF MEXICO...WILL
RESULT IN AN INCREASING GRADIENT ACROSS THE COASTAL WATERS SUNDAY
NIGHT THROUGH TUESDAY. A STRONG COLD FRONT WILL MOVE THROUGH THE
REGION TUESDAY NIGHT...WITH A POTENTIALLY SIGNIFICANT SURGE IN THE
WINDS BEHIND THE SYSTEM THROUGH THURSDAY AS A STRONG RIDGE OF HIGH
PRESSURE BUILDS NORTH OF THE REGION. SMALL CRAFT CONDITIONS FOR
WINDS/SEAS OR A COMBINATION OF THE TWO MAY DEVELOP AS EARLY AS
SUNDAY NIGHT ACROSS THE OUTER GEORGIA WATERS...WITH SMALL CRAFT
CONDITIONS EXPECTED TO MOVE INTO THE NEARSHORE WATERS MONDAY OR
MONDAY NIGHT. SMALL CRAFT CONDITIONS ARE THEN EXPECTED TO CONTINUE
FOR ALL WATERS WITH THE EXCEPTION OF CHARLESTON HARBOR THROUGH
THURSDAY. HEADLINE THRESHOLDS MAY NOT BE REACHED IN CHARLESTON
HARBOR THROUGH TUESDAY...BUT SMALL CRAFT CONDITIONS APPEAR FAIRLY
LIKELY TUESDAY NIGHT THROUGH WEDNESDAY NIGHT AS THE STRONG WIND
SURGE DEVELOPS BEHIND THE COLD FRONTAL PASSAGE. IN FACT DEPENDING
ON THE POSITIONING AND STRENGTH OF HIGH PRESSURE TO THE NORTH AND
THE TROPICAL OR SUBTROPICAL SYSTEM TO THE SOUTH...GALE CONDITIONS
MAY BE REACHED ACROSS PORTIONS OF THE WATERS IN THE TUESDAY NIGHT
THROUGH WEDNESDAY NIGHT TIME FRAME.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
000
FXUS62 KGSP 072343
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
643 PM EST SAT NOV 7 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
ABUNDANT MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS EXPECTED TO
MOVE INTO THE CAROLINAS AND NORTH GEORGIA AHEAD OF A COLD FRONT ON
TUESDAY...WITH THE FRONT EXPECTED TO CROSS THE AREA LATE TUESDAY
INTO EARLY WEDNESDAY. HIGH PRESSURE WILL THEN RETURN FOR THE LATER
HALF OF NEXT WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
UPPER RIDGE OVER THE AREA CONTINUES TO STRENGTHEN TONIGHT AS HIGH
PRESSURE RIDGE REMAINS CENTERED OVER THE AREA. CLEAR SKIES AND LIGHT
WINDS WILL LEAD TO GOOD RADIATIONAL CONDITIONS ONCE AGAIN. HAVE
TRENDED TOWARD THE COOLER GUIDANCE WITH RADIATIONAL PATTERN...WARMER
RIDGES THAN VALLEYS AND WARMER I-85 NE GA/SC AND NC THERMAL BELT.
TEMPS WILL BE COOL ENUF FOR AREAS OF FROST FROM THE SRN NC PIEDMONT
AND ERN UPSTATE TO THE SRN PORTIONS OF THE WRN UPSTATE AND NE GA.
WILL ISSUE A FROST ADV...ALTHOUGH THE FROST OVER THE SRN PIEDMONT
WILL LIKELY BE LIMITED TO RURAL AND COLDER LOCATIONS.
UPPER RIDGE STRENGTHENS EVEN FURTHER SUNDAY AS HIGH PRESSURE RIDGE
REMAINS OVER THE AREA. THICKNESS INCREASE...LIGHT SLY WINDS AND FULL
SUN WILL LEAD TO A VERY WARM DAY...AROUND 10 DEGREES ABOVE NORMAL.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
AS OF 230 PM EDT SATURDAY...A WELL AMPLIFIED UPPER RIDGE OVER THE
SOUTHEAST ON SUNDAY NIGHT WILL MOVE OFF THE EAST COAST ON MONDAY
NIGHT. THE UPPER TROUGH IN ITS WAKE WILL PROGRESS TO THE
APPALACHIANS ON TUESDAY...WHEN A WELL DEFINED SOUTHERN STREAM
SHORTWAVE IN ITS BASE WILL CROSS OUR AREA. DRY HIGH PRESSURE WILL
PERSIST OVER THE MID ATLANTIC COAST SUNDAY NIGHT AND MONDAY. ON
MONDAY NIGHT THE GFS SHOWS GULF MOISTURE ASSOCIATED WITH TROPICAL
SYSTEM IDA MOVING INTO GA AND THE WESTERN CAROLINAS...WITH THE
SURFACE PRESSURE GRADIENT TIGHTENING OVER THE SAVANNAH RIVER VALLEY.
THE TPC FORECAST FOR IDA SHOWS IT REMAINING IN THE NORTHEAST GULF
INTO TUESDAY...SO CONFIDENCE ON MOISTURE OVER OUR AREA IS NOT HIGH.
NEVERTHELESS...WITH ISENTROPIC UPGLIDE AND A MOIST UPSLOPE COMPONENT
EXPECTED...THE FORECAST WILL SHOW INCREASING CLOUD COVER AND A
CHANCE OF PRECIPITATION TUESDAY AND TUESDAY NIGHT...BEFORE A COLD
FRONT SWEEPS ACROSS THE AREA FROM THE NORTHWEST LATE TUESDAY NIGHT.
MAXIMUMS TEMPERATURES WILL EXPERIENCE A DOWNWARD TREND AS HEIGHTS
FALL ALOFT AND CLOUD COVER INCREASES. MINIMUM TEMPERATURES WILL RISE
WITH THE INCREASE IN CLOUD COVER AND LOW LEVEL MOISTURE...THEN DROP
OFF TUESDAY NIGHT BEHIND THE FRONT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 200 PM SATURDAY...THE EXTENDED PERIOD STARTS WITH AN EXITING
LOW PRES SYSTEM TO OUR EAST...WITH DECENT LLVL CAA AND DOWNSLOPE
FLOW ACRS THE CWFA. DRY CP AIR MASS PUSHES INTO THE AREA FROM LATE
WED THRU FRIDAY UNDER CONFLUENT FLOW DOWNSTREAM OF SPLIT WRN NOAM
FLOW. SO EXPECT TEMPS AT OR SLIGHTLY BELOW NORMAL UNDER MOSTLY CLEAR
SKIES FOR WED AND THU.
FRIDAY INTO NEXT WEEKEND...GUIDANCE IN DECENT AGREEMENT ON SFC HI
PRES SHIFTING EAST OFF THE COAST...AS UPR LVL ENERGY BEGINS TO
ADVANCE EAST INTO THE GREAT PLAINS. FOR NOW...JUST ADDED A SLGT CHC
POP FOR SATURDAY WITH INCREASING CLOUDS AND A WARMING TREND.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AT KCLT AND ELSEWHERE...DRY HIGH PRESSURE WILL PERSIST OVER THE
TERMINAL FORECAST AREA THROUGH THE PERIOD. LIGHT SOUTHERLY WINDS
THIS EVENING WILL BECOME VARIABLE OVERNIGHT...WITH A LIGHT NORTHERLY
COMPONENT POSSIBLE AT TIMES...BEFORE RETURNING TO PREDOMINANT LIGHT
SOUTH OR SOUTHEAST FLOW BY NOON SUNDAY. MOS REMAINS MIXED ON FOG
POTENTIAL LATE TONIGHT AT KAVL AND KAND...BUT MODEL PROFILES DO NOT
APPEAR SUPPORTIVE OF AN MVFR FOG MENTION AT PRESENT. WILL CONTINUE
VFR TAFS OVERNIGHT. A FEW HIGH CLOUDS MAY APPEAR FROM THE S SUNDAY
AFTERNOON.
OUTLOOK...VFR CONDITIONS UNDER HIGH PRESSURE WILL CONTINUE THROUGH
MONDAY. AREAS OF MORNING FOG WILL BE POSSIBLE...MAINLY AROUND RIVERS
AND LAKES NEAR KAVL AND KAND. A COLD FRONT IS EXPECTED TO MOVE IN ON
TUESDAY WITH A CHC SHWRS AND CIG/VSBY RESTRICTIONS. THE FRONT SHOULD
MOVE EAST WED WITH VFR GRADUALLY RETURNING.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FROST ADVISORY FROM 4 AM TO 8 AM EST SUNDAY FOR GAZ028-029.
NC...FROST ADVISORY FROM 4 AM TO 8 AM EST SUNDAY FOR NCZ068>072-082.
SC...FROST ADVISORY FROM 4 AM TO 8 AM EST SUNDAY FOR SCZ008>014-019.
&&
$$
SYNOPSIS...JPT
NEAR TERM...RWH
SHORT TERM...JAT
LONG TERM...ARK
AVIATION...HG
000
FXUS62 KCAE 072327
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
627 PM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN IN CONTROL OF THE REGION THROUGH EARLY
NEXT WEEK. A COLD FRONT ALONG WITH A SURGE OF TROPICAL MOISTURE
WILL AFFECT THE AREA LATE MONDAY INTO TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE CENTERED OVER THE MID-ATLANTIC STATES WILL CONTINUE
TO DOMINATE THE REGION WITH CLEAR SKIES AND LIGHT WINDS TONIGHT.
WITH FORECAST LOWS IN THE MID 30S...WILL ISSUE A FROST ADVISORY
FOR THE NORTHERN MIDLANDS LATE TONIGHT. SOME PATCHY FROST POSSIBLE
IN A FEW OTHER LOCATIONS SUCH AS THE CSRA...BUT NOT ENOUGH TO
WARRANT AN ADVISORY SO WILL JUST ADVERTISE IN THE ZFP. OVERNIGHT
LOWS GENERALLY RANGING FROM THE MID 30S TO NEAR 40 DEGREES.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
DRY WEATHER WILL PERSIST SUNDAY INTO EARLY MONDAY AS THE HIGH
PRESSURE CENTER MOVES OFFSHORE. TEMPERATURES WILL MODERATE A BIT
EACH DAY SO FORECAST TEMPS CLOSE TO MODEL CONSENSUS. CLOUDS WILL
INCREASE MONDAY AHEAD OF AN APPROACHING COLD FRONT TO THE WEST
ALONG WITH TROPICAL MOISTURE FROM THE SOUTH ASSOCIATED WITH T.S.
IDA. STILL SOME QUESTION AS TO THE FUTURE TRACK OF IDA...BUT
MOISTURE AHEAD TO THE SYSTEM SHOULD SPREAD FROM THE NORTHERN GULF
OF MEXICO INTO GA/SC BY LATE MONDAY NIGHT. WILL INCREASE POPS TO
THE CHANCE CATEGORY FOR MONDAY NIGHT.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS MENTIONED EARLIER...STILL SOME QUESTION CONCERNING THE FUTURE
PATH OF T.S. IDA...BUT MODELS SEEM TO INDICATE THAT THE BEST
MOISTURE SURGE ASSOCIATED WITH IDA WILL BE ON TUESDAY. WILL GO
WITH HIGH CHANCE POPS FOR MUCH OF THE AREA...POSSIBLY LIKELY POPS
ACROSS THE CSRA. A COLD FRONT WILL ALSO APPROACH FROM THE WEST BY
LATE TUESDAY. DRY HIGH PRESSURE WILL BUILD IN FROM THE WEST LATE
WEDNESDAY THROUGH FRIDAY. ANOTHER COLD FRONT APPROACHES BY LATE
SATURDAY SO WILL INCLUDE A SLIGHT CHANCE POP BY THEN. FORECAST
TEMPS CLOSE TO MEX GUIDANCE.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
DRY HIGH PRESSURE WILL REMAIN IN PLACE THROUGH THE TAF PERIOD.
THREAT FOR FOG APPEARS HIGHER AT AGS AND OGB WHERE THE ADDED COOLING
AND MOISTURE ASSOCIATED WITH THE RIVER VALLEYS SUPPORT A PERIOD OF
MVFR OR IFR FOG DURING THE EARLY MORNING HOURS. MVFR VISIBILITIES
FOR BRIEF PERIODS AT CAE AND CUB TOWARDS MORNING. OTHERWISE...VFR
CONDITIONS AT ALL SITES THROUGH THE PERIOD.
EXTENDED AVIATION OUTLOOK...WIDESPREAD CEILING AND VISIBILITY
RESTRICTIONS MAY OCCUR TUESDAY INTO WEDNESDAY ASSOCIATED WITH
ISENTROPIC LIFT.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...FROST ADVISORY FROM 3 AM TO 7 AM EST SUNDAY FOR SCZ015-016-
020>022.
GA...NONE.
&&
$$
000
FXUS62 KCHS 072050
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
350 PM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE
WEEKEND. THE COMBINATION OF TROPICAL CYCLONE IDA...OR ITS REMNANTS...
LIFTING NORTHWARD THROUGH THE GULF OF MEXICO AND A COLD FRONT
APPROACHING FROM THE NORTHWEST WILL KEEP THINGS UNSETTLED DURING
THE EARLY TO MIDDLE PART OF NEXT WEEK. HIGH PRESSURE WILL THEN
BUILD BACK INTO THE REGION BY THURSDAY AND REMAIN THE DOMINANT
WEATHER FEATURE THROUGH THE FIRST PART OF THE UPCOMING WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
ELONGATED HIGH PRESSURE CENTERED OVER THE NORTH CAROLINA OUTER
BANKS THIS AFTERNOON WILL REMAIN ACROSS THE REGION TONIGHT. PATCHY
CUMULUS THAT HAS DEVELOPED OVER PARTS OF INLAND MCINTOSH COUNTY
WILL QUICKLY DISSIPATE OVER THE NEXT 1-2 HOURS AS SURFACE HEATING
WANES WITH THE APPROACH OF SUNSET. CLEAR SKIES AND CALM WINDS WILL
PROMOTE A STRONG RADIATIONAL SETUP AGAIN TONIGHT EXCEPT ALONG THE
IMMEDIATE COAST WHERE A RESIDUAL PRESSURE GRADIENT BETWEEN THE
INLAND SURFACE HIGH AND A WEAK COASTAL TROUGH FORMING OFFSHORE
WILL KEEP THE ATMOSPHERE A BIT MORE MIXED. EXPECT LOWS FROM THE
UPPER 30S WELL INLAND TO THE MID-UPPER 50S ALONG THE BEACHES.
THERE IS SOME CONCERN FOR SOME FROST FORMATION WELL INLAND TONIGHT
WHERE CO-OP TEMPERATURE GUIDANCE SUGGEST LOWS MAY DROP INTO THE
36-37 DEGREE RANGE IN A FEW SHELTERED POCKETS. THE GREATEST FROST
POTENTIAL WILL OCCUR ROUGHLY NORTH OF A PERKINS-HILLTONIA-
CROCKETVILLE-SMOAKS LINE BUT ATTM WE BELIEVE ANY FROST THAT FORMS
WILL BE FAIRLY PATCHY. WILL FORGO THE ISSUANCE OF A FROST ADVISORY
PER COORDINATION WITH WFO COLUMBIA...BUT THE EVENING SHIFT WILL
CAREFULLY MONITOR TRENDS AS ANY LOWERING OF TEMPERATURES IN THIS
AREA WILL NECESSITATE THE ISSUANCE OF AN ADVISORY.
&&
.SHORT TERM /SUNDAY/...
HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT WILL HOLD OVER THE
REGION SUNDAY. TROPICAL CYCLONE IDA OVER THE WESTERN CARIBBEAN IS
FORECAST BY NHC TO MOVE THROUGH THE YUCATAN CHANNEL SUNDAY
AFTERNOON. THE GRADIENT BETWEEN THE HIGH TO THE NORTH AND IDA WILL
BEGIN TO TIGHTEN SUNDAY AFTERNOON BUT WINDS LOOK TO GO NO HIGHER
THAN 10-15 MPH. A WEAK AND DIFFUSE COASTAL TROUGH OFFSHORE WILL
BECOME ABSORBED THE THE SYNOPTIC EASTERLY FLOW DURING THIS TIME
AND WILL HAVE LITTLE IF ANY SIGNIFICANT IMPACT ON ANY SENSIBLE
WEATHER ELEMENTS AS IT DISSIPATES. SLIGHTLY HIGHER DEWPOINTS COULD
SUPPORT A BIT MORE IN THE WAY OF SHALLOW CUMULUS FROM LATE MORNING
THROUGH THE MID AFTERNOON HOURS...BUT STILL EXPECT SUNNY TO MOSTLY
SUNNY SKIES TO PREVAIL WITH A FEW HOURS OF PARTLY CLOUDY CONDITIONS
POSSIBLE ALONG THE I-95 CORRIDOR FROM SAVANNAH SOUTH. HIGHS WILL
REACH IN THE MID-UPPER 70S PER LOW-LEVEL THICKNESS PROGS EXCEPT
AT THE BEACHES WHERE CONSIDERABLY COOLER CONDITIONS WILL BE FOUND.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE GUIDANCE IS IN DECENT AGREEMENT THROUGHOUT THE EXTENDED
PERIODS THIS AFTERNOON...WITH SOME DIFFERENCES NOTED WITH RESPECT TO
THE EVOLUTION OF TROPICAL CYCLONE IDA OR THE REMNANTS OF THE SYSTEM
DURING THE EARLY TO MID WEEK TIME FRAME.
AN UPPER TROUGH MOVING THROUGH THE SOUTHERN PLAINS INTO THE LOWER
MISSISSIPPI VALLEY IN COMBINATION WITH DEEP LAYER RIDGING OVER THE
WESTERN ATLANTIC...WILL LIFT TROPICAL CYCLONE IDA OR THE REMNANTS OF
THE SYSTEM NORTHWARD THROUGH THE GULF OF MEXICO SUNDAY NIGHT THROUGH
TUESDAY. INITIALLY THE DRY AIRMASS IN PLACE...LACK OF ANY DEEP
MOISTURE AND ANY SIGNIFICANT FORCING FOR ASCENT...SHOULD PRECLUDE
MUCH IN THE WAY OF RAINFALL POTENTIAL. CAN/T RULE OUT A STRAY SHOWER
ROLLING IN OFF THE ATLANTIC MONDAY AFTERNOON...BUT FOR NOW WILL
CONTINUE WITH A RAIN FREE FORECAST SUNDAY NIGHT THROUGH MONDAY. DEEP
TROPICAL MOISTURE WILL STEADILY INCREASE ACROSS THE FORECAST AREA
TUESDAY...AND WITH BOTH ISENTROPIC ASCENT AND DYNAMIC FORCING
SWINGING INTO THE REGION...WILL CARRY LIKELY POPS ALL AREA.
A STRONG UPPER LEVEL TROUGH WILL THEN SHIFT EASTWARD THROUGH THE
EASTERN GREAT LAKES AND NEW ENGLAND STATES TUESDAY NIGHT...ALLOWING
A SURFACE COLD FRONT TO PUSH SOUTHEASTWARD THROUGH THE FORECAST
AREA. STRONG HIGH PRESSURE WILL BUILD NORTH OF THE REGION WEDNESDAY
THROUGH THURSDAY...BEFORE SHIFTING INTO THE WESTERN ATLANTIC FOR THE
TAIL END OF THE WORK WEEK AND INTO THE FIRST PART OF THE UPCOMING
WEEKEND. WILL CARRY LIKELY POPS TUESDAY NIGHT AS DEEP MOISTURE AND
FORCING WILL REMAIN IN PLACE ACROSS THE FORECAST AREA AS THE COLD
FRONT PUSHES SOUTHWARD THROUGH THE AREA. STILL SOME TIMING
DISCONTINUITIES IN THE MODELS WITH RESPECT TO HOW QUICKLY THE COLD
FRONT PUSHES THROUGH THE AREA...SO WILL KEEP CHANCE POPS GOING
THROUGH THE DAY WEDNESDAY. HIGH PRESSURE WILL BECOME MORE DOMINANT
WEDNESDAY NIGHT THROUGH SATURDAY...SO WILL MAINTAIN THE RAIN FREE
FORECAST. DEPENDING ON HOW THE POSITIONING OF THE RIDGE AXIS NORTH
OF THE REGION THURSDAY THROUGH SATURDAY...THERE IS A POTENTIAL FOR
SOME SHOWERS TO PUSH ONSHORE OFF THE ATLANTIC...BUT PROBABILITIES
APPEAR TOO LOW TO MENTION IN THE FORECAST AT THIS TIME.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH 18Z SUNDAY FOR KCHS
AND KSAV. WITH A PERSISTENT ONSHORE FLOW AND MODELS SHOWING A SLIGHT
INCREASE IN LOW LEVEL MOISTURE...EXPECT A FEW CUMULUS TO DEVELOP
ACROSS THE AREA THIS AFTERNOON. MAINLY CLEAR SKIES AND CALM WINDS
WILL PREVAIL OVERNIGHT BUT LOW LEVEL MOISTURE WILL CONTINUE TO
ADVECT INTO THE AREA AS AN ONSHORE FLOW REDEVELOPS SUNDAY AFTERNOON.
EXTENDED AVIATION OUTLOOK...VFR CONDITIONS WILL PREVAIL THROUGH
MONDAY. THE COMBINATION OF A STORM SYSTEM LIFTING NORTHEAST THROUGH
THE GULF OF MEXICO AND A COLD FRONT APPROACHING FROM THE NORTHWEST
WILL RESULT IN UNSETTLED WEATHER AND THE POTENTIAL FOR MVFR OR IFR
CONDITIONS MONDAY NIGHT THROUGH WEDNESDAY. LLWS IS ALSO POSSIBLE
WEDNESDAY MORNING. VFR CONDITIONS ARE THEN EXPECTED TO RETURN
WEDNESDAY NIGHT AND THURSDAY.
&&
.MARINE...
NORTHEAST WINDS WILL INCREASE TO 10-15 TONIGHT ACROSS MOST OF THE
MARINE AREA AS THE GRADIENT TIGHTENS BETWEEN HIGH PRESSURE INLAND
AND A WEAK COASTAL TROUGH DEVELOPING OFFSHORE. SEAS 2 FT NEARSHORE
AND BUILDING TO 3-4 FT OFFSHORE.
NORTHEAST WINDS WILL CONTINUE INTO SUNDAY BUT COULD LOCALLY VEER
EASTERLY NEAR THE COAST AS A RESULTANT SEA BREEZE CIRCULATION
DEVELOPS. SPEEDS OF 10-15 KT WILL PERSIST WITH SEAS WILL BUILD TO
2-4 FT NEARSHORE WATERS AND 4-5 FT OFFSHORE WATERS.
SUNDAY NIGHT THROUGH THURSDAY...HIGH PRESSURE OVER THE WESTERN
ATLANTIC IN COMBINATION WITH TROPICAL CYCLONE IDA OR THE REMNANTS
OF THE SYSTEM TRACKING NORTHWARD THROUGH THE GULF OF MEXICO...WILL
RESULT IN AN INCREASING GRADIENT ACROSS THE COASTAL WATERS SUNDAY
NIGHT THROUGH TUESDAY. A STRONG COLD FRONT WILL MOVE THROUGH THE
REGION TUESDAY NIGHT...WITH A POTENTIALLY SIGNIFICANT SURGE IN THE
WINDS BEHIND THE SYSTEM THROUGH THURSDAY AS A STRONG RIDGE OF HIGH
PRESSURE BUILDS NORTH OF THE REGION. SMALL CRAFT CONDITIONS FOR
WINDS/SEAS OR A COMBINATION OF THE TWO MAY DEVELOP AS EARLY AS
SUNDAY NIGHT ACROSS THE OUTER GEORGIA WATERS...WITH SMALL CRAFT
CONDITIONS EXPECTED TO MOVE INTO THE NEARSHORE WATERS MONDAY OR
MONDAY NIGHT. SMALL CRAFT CONDITIONS ARE THEN EXPECTED TO CONTINUE
FOR ALL WATERS WITH THE EXCEPTION OF CHARLESTON HARBOR THROUGH
THURSDAY. HEADLINE THRESHOLDS MAY NOT BE REACHED IN CHARLESTON
HARBOR THROUGH TUESDAY...BUT SMALL CRAFT CONDITIONS APPEAR FAIRLY
LIKELY TUESDAY NIGHT THROUGH WEDNESDAY NIGHT AS THE STRONG WIND
SURGE DEVELOPS BEHIND THE COLD FRONTAL PASSAGE. IN FACT DEPENDING
ON THE POSITIONING AND STRENGTH OF HIGH PRESSURE TO THE NORTH AND
THE TROPICAL OR SUBTROPICAL SYSTEM TO THE SOUTH...GALE CONDITIONS
MAY BE REACHED ACROSS PORTIONS OF THE WATERS IN THE TUESDAY NIGHT
THROUGH WEDNESDAY NIGHT TIME FRAME.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
000
FXUS62 KCAE 071946
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
246 PM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN IN CONTROL OF THE REGION THROUGH EARLY
NEXT WEEK. A COLD FRONT ALONG WITH A SURGE OF TROPICAL MOISTURE
WILL AFFECT THE AREA LATE MONDAY INTO TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE CENTERED OVER THE MID-ATLANTIC STATES WILL CONTINUE
TO DOMINATE THE REGION WITH CLEAR SKIES AND LIGHT WINDS TONIGHT.
WITH FORECAST LOWS IN THE MID 30S...WILL ISSUE A FROST ADVISORY
FOR THE NORTHERN MIDLANDS LATE TONIGHT. SOME PATCHY FROST POSSIBLE
IN A FEW OTHER LOCATIONS SUCH AS THE CSRA...BUT NOT ENOUGH TO
WARRANT AN ADVISORY SO WILL JUST ADVERTISE IN THE ZFP. OVERNIGHT
LOWS GENERALLY RANGING FROM THE MID 30S TO NEAR 40 DEGREES.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
DRY WEATHER WILL PERSIST SUNDAY INTO EARLY MONDAY AS THE HIGH
PRESSURE CENTER MOVES OFFSHORE. TEMPERATURES WILL MODERATE A BIT
EACH DAY SO FORECAST TEMPS CLOSE TO MODEL CONSENSUS. CLOUDS WILL
INCREASE MONDAY AHEAD OF AN APPROACHING COLD FRONT TO THE WEST
ALONG WITH TROPICAL MOISTURE FROM THE SOUTH ASSOCIATED WITH T.S.
IDA. STILL SOME QUESTION AS TO THE FUTURE TRACK OF IDA...BUT
MOISTURE AHEAD TO THE SYSTEM SHOULD SPREAD FROM THE NORTHERN GULF
OF MEXICO INTO GA/SC BY LATE MONDAY NIGHT. WILL INCREASE POPS TO
THE CHANCE CATEGORY FOR MONDAY NIGHT.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS MENTIONED EARLIER...STILL SOME QUESTION CONCERNING THE FUTURE
PATH OF T.S. IDA...BUT MODELS SEEM TO INDICATE THAT THE BEST
MOISTURE SURGE ASSOCIATED WITH IDA WILL BE ON TUESDAY. WILL GO
WITH HIGH CHANCE POPS FOR MUCH OF THE AREA...POSSIBLY LIKELY POPS
ACROSS THE CSRA. A COLD FRONT WILL ALSO APPROACH FROM THE WEST BY
LATE TUESDAY. DRY HIGH PRESSURE WILL BUILD IN FROM THE WEST LATE
WEDNESDAY THROUGH FRIDAY. ANOTHER COLD FRONT APPROACHES BY LATE
SATURDAY SO WILL INCLUDE A SLIGHT CHANCE POP BY THEN. FORECAST
TEMPS CLOSE TO MEX GUIDANCE.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
DRY HIGH PRESSURE WILL REMAIN IN PLACE THROUGH THE TAF PERIOD.
EXPECT MAINLY VFR CONDITIONS THROUGH THE TAF PERIOD. THREAT FOR
FOG APPEARS HIGHER AT AGS AND OGB WHERE THE ADDED COOLING AND
MOISTURE ASSOCIATED WITH THE RIVER VALLEYS SUPPORT A PERIOD OF
MVFR OR IFR FOG DURING THE EARLY MORNING HOURS.
EXTENDED AVIATION OUTLOOK...WIDESPREAD CEILING AND VISIBILITY
RESTRICTIONS MAY OCCUR TUESDAY INTO WEDNESDAY ASSOCIATED WITH
ISENTROPIC LIFT.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...FROST ADVISORY FROM 3 AM TO 7 AM EST SUNDAY FOR SCZ015-016-
020>022.
GA...NONE.
&&
$$
000
FXUS62 KGSP 071931
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
231 PM EST SAT NOV 7 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
ABUNDANT MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS EXPECTED TO
MOVE INTO THE CAROLINAS AND NORTH GEORGIA AHEAD OF A COLD FRONT ON
TUESDAY...WITH THE FRONT EXPECTED TO CROSS THE AREA LATE TUESDAY
INTO EARLY WEDNESDAY. HIGH PRESSURE WILL THEN RETURN FOR THE LATER
HALF OF NEXT WEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
UPPER RIDGE OVER THE AREA CONTINUES TO STRENGTHEN TONIGHT AS HIGH
PRESSURE RIDGE REMAINS CENTERED OVER THE AREA. CLEAR SKIES AND LIGHT
WINDS WILL LEAD TO GOOD RADIATIONAL CONDITIONS ONCE AGAIN. HAVE
TRENDED TOWARD THE COOLER GUIDANCE WITH RADIATIONAL PATTERN...WARMER
RIDGES THAN VALLEYS AND WARMER I-85 NE GA/SC AND NC THERMAL BELT.
TEMPS WILL BE COOL ENUF FOR AREAS OF FROST FROM THE SRN NC PIEDMONT
AND ERN UPSTATE TO THE SRN PORTIONS OF THE WRN UPSTATE AND NE GA.
WILL ISSUE A FROST ADV...ALTHOUGH THE FROST OVER THE SRN PIEDMONT
WILL LIKELY BE LIMITED TO RURAL AND COLDER LOCATIONS.
UPPER RIDGE STRENGTHENS EVEN FURTHER SUNDAY AS HIGH PRESSURE RIDGE
REMAINS OVER THE AREA. THICKNESS INCREASE...LIGHT SLY WINDS AND FULL
SUN WILL LEAD TO A VERY WARM DAY...AROUND 10 DEGREES ABOVE NORMAL.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
AS OF 230 PM EDT SATURDAY...A WELL AMPLIFIED UPPER RIDGE OVER THE
SOUTHEAST ON SUNDAY NIGHT WILL MOVE OFF THE EAST COAST ON MONDAY
NIGHT. THE UPPER TROUGH IN ITS WAKE WILL PROGRESS TO THE
APPALACHIANS ON TUESDAY...WHEN A WELL DEFINED SOUTHERN STREAM
SHORTWAVE IN ITS BASE WILL CROSS OUR AREA. DRY HIGH PRESSURE WILL
PERSIST OVER THE MID ATLANTIC COAST SUNDAY NIGHT AND MONDAY. ON
MONDAY NIGHT THE GFS SHOWS GULF MOISTURE ASSOCIATED WITH TROPICAL
SYSTEM IDA MOVING INTO GA AND THE WESTERN CAROLINAS...WITH THE
SURFACE PRESSURE GRADIENT TIGHTENING OVER THE SAVANNAH RIVER VALLEY.
THE TPC FORECAST FOR IDA SHOWS IT REMAINING IN THE NORTHEAST GULF
INTO TUESDAY...SO CONFIDENCE ON MOISTURE OVER OUR AREA IS NOT HIGH.
NEVERTHELESS...WITH ISENTROPIC UPGLIDE AND A MOIST UPSLOPE COMPONENT
EXPECTED...THE FORECAST WILL SHOW INCREASING CLOUD COVER AND A
CHANCE OF PRECIPITATION TUESDAY AND TUESDAY NIGHT...BEFORE A COLD
FRONT SWEEPS ACROSS THE AREA FROM THE NORTHWEST LATE TUESDAY
NIGHT.
MAXIMUMS TEMPERATURES WILL EXPERIENCE A DOWNWARD TREND AS HEIGHTS
FALL ALOFT AND CLOUD COVER INCREASES. MINIMUM TEMPERATURES WILL RISE
WITH THE INCREASE IN CLOUD COVER AND LOW LEVEL MOISTURE...THEN
DROP OFF TUESDAY NIGHT BEHIND THE FRONT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 200 PM SATURDAY...THE EXTENDED PERIOD STARTS WITH AN EXITING
LOW PRES SYSTEM TO OUR EAST...WITH DECENT LLVL CAA AND DOWNSLOPE
FLOW ACRS THE CWFA. DRY CP AIR MASS PUSHES INTO THE AREA FROM LATE
WED THRU FRIDAY UNDER CONFLUENT FLOW DOWNSTREAM OF SPLIT WRN NOAM
FLOW. SO EXPECT TEMPS AT OR SLIGHTLY BELOW NORMAL UNDER MOSTLY CLEAR
SKIES FOR WED AND THU.
FRIDAY INTO NEXT WEEKEND...GUIDANCE IN DECENT AGREEMENT ON SFC HI
PRES SHIFTING EAST OFF THE COAST...AS UPR LVL ENERGY BEGINS TO
ADVANCE EAST INTO THE GREAT PLAINS. FOR NOW...JUST ADDED A SLGT CHC
POP FOR SATURDAY WITH INCREASING CLOUDS AND A WARMING TREND.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
AT KCLT AND ELSEWHERE...SKC WITH SOUTH TO SOUTHWEST WINDS NEAR 10
KTS. LIGHT AND VARIABLE TO CALM WINDS THIS EVENING...WITH LIGHT SSW
DEVELOPING SUN MORN. THE EXCEPTION IS KAVL WHERE WINDS SUN WILL
START OUT LIGHT NLY. FOG LIKELY AGAIN AT KCEU AND THE LAKE NEAR
KAND. VALLEY FOG MORE LIKELY IN THE NC MTNS. GUIDANCE MIXED IF ANY
OF THIS FOG WILL AFFECT KAND OR KAVL. WILL KEEP FCST VFR FOR NOW AND
LET LATER SHIFTS SEE IF ANY TRENDS DEVELOP.
OUTLOOK...PREDOMINATE VFR WITH HIGH PRESSURE INTO THE FIRST PART OF
NEXT WEEK. EXPECTED AREAS OF MRNG FOG...MAINLY NEAR RIVERS AND
LAKES. COLD FRONT MOVES IN TUE WITH CHC SHWRS AND CIG/VSBY
RESTRICTIONS. FRONT MOVES EAST WED WITH VFR RETURNING.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FROST ADVISORY FROM 4 AM TO 8 AM EST SUNDAY FOR GAZ028-029.
NC...FROST ADVISORY FROM 4 AM TO 8 AM EST SUNDAY FOR NCZ068>072-082.
SC...FROST ADVISORY FROM 4 AM TO 8 AM EST SUNDAY FOR SCZ008>014-019.
&&
$$
SYNOPSIS...JPT
NEAR TERM...RWH
SHORT TERM...JAT
LONG TERM...ARK
AVIATION...RWH
000
FXUS62 KGSP 071738
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1238 PM EST SAT NOV 7 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS EXPECTED TO MOVE INTO
THE CAROLINAS AND NORTH GEORGIA AHEAD OF A COLD FRONT TUESDAY...WITH
THE FRONT EXPECTED TO CROSS THE AREA ON TUESDAY NIGHT AND EARLY
WEDNESDAY. HIGH PRESSURE WILL THEN RETURN FOR THE LATER HALF OF NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPPER RIDGE CONTINUES TO BUILD OVER THE AREA TODAY WHILE CENTER OF
SFC HIGH MOVES INTO THE ATLANTIC. SFC RIDGING REMAINS OVER THE AREA
THOUGH. SOUTH TO SOUTHWEST WINDS PICK UP AS THICKNESSES RISE AND
CIRRUS MOVES TO OUR EAST. HIGHS SHOULD BE A FEW DEGREES HIGHER THAN
FRIDAY. CURRENT FCST HAS THIS COVERED WITH ONLY MINOR ADJUSTMENTS
NEEDED.
UPPER RIDGE CONTINUES TO BUILD TONIGHT WITH S-SW WINDS AT THE SFC.
EVEN THOUGH SKIES WILL BE MCLEAR OVERNIGHT...RISING THICKNESS WILL
KEEP TEMPS IN THE U30S-L40S ACROSS THE PIEDMONT WITH 30S IN THE MTNS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 225 AM SATURDAY...THE UPPER RIDGE WILL CONTINUE BUILD ALONG
THE EAST COAST THROUGH SUNDAY NIGHT...BEFORE BEGINNING A SLIGHT
EASTWARD PROGRESSION/BREAK DOWN BY THE END OF THE SHORT TERM. HIGH
MID-LEVEL HEIGHTS/INCREASED THICKNESS WILL RESULT IN VERY WARM MAXES
THROUGH THE PERIOD...WITH MANY AREAS OF THE PIEDMONT EXPECTED TO
REACH THE MID 70S SUNDAY AFTERNOON. EVEN THE MTN VALLEYS COULD SEE
THE LOWER 70S. MUCH OF THE SAME IS EXPECTED ON MONDAY...ALTHOUGH
INCREASING HIGH CLOUDS MAY MODERATE TEMPS JUST A BIT. ALTHOUGH GOOD
RADIATIONAL COOLING CONDITIONS SHOULD ALLOW LOWS TO SETTLE TO NEAR
NORMAL LEVELS...FROST/FREEZE WILL NOT BE A CONCERN DURING THIS
TIME.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 230 AM SATURDAY...WEATHER BECOMES MORE ACTIVE DURING THE EARLY
PART OF THE MEDIUM RANGE...AS A SW TROUGH DIGGING ACROSS THE UPPER
MIDWEST RESULTS IN COMPLETE BREAKDOWN/EASTWARD PROGRESSION OF THE
UPPER RIDGE. MEANWHILE...TROPICAL STORM IDA IS EXPECTED TO BE MOVING
NORTHEAST ACROSS THE CENTRAL/NORTHERN GULF EARLY TUESDAY. THE GFS
AND ECMWF ARE IN VERY GOOD AGREEMENT IN SPREADING MOISTURE
ASSOCIATED WITH IDA INTO THE CAROLINAS TUESDAY...BEFORE THE UPPER
TROUGH AND ASSOCIATED COLD FRONT SWEEP IT OFF THE SOUTHEAST COAST
EARLY WEDNESDAY. THE NAM IS NOT AS EXCITED ABOUT THIS SCENARIO.
CONSIDERING ITS TRACK RECORD AND SUPPORT FROM OTHER MODELS...IT
APPEARS THE GFS IS THE WAY TO GO WITH THIS FORECAST. HOWEVER...THERE
IS STILL SUFFICIENT UNCERTAINTY TO CONTINUE WITH A CONSERVATIVE POP
FORECAST. WE WILL MAINTAIN AN AREA OF LIKELY POPS ACROSS THE SOUTH
TUESDAY...BUT HAVE ACTUALLY TEMPERED POPS A BIT ACROSS THE NORTH.
AFTER LINGERING TOKEN CHANCE POPS ACROSS THE AREA TUE NIGHT...THE
REMAINDER OF THE EXTENDED PERIODS APPEAR TO BE DOMINATED BY DRY/COOL
HIGH PRESSURE.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AT KCLT AND ELSEWHERE...SKC WITH SOUTH TO SOUTHWEST WINDS NEAR 10
KTS. LIGHT AND VARIABLE TO CALM WINDS THIS EVENING...WITH LIGHT SSW
DEVELOPING SUN MORN. THE EXCEPTION IS KAVL WHERE WINDS SUN WILL
START OUT LIGHT NLY. FOG LIKELY AGAIN AT KCEU AND THE LAKE NEAR
KAND. VALLEY FOG MORE LIKELY IN THE NC MTNS. GUIDANCE MIXED IF ANY
OF THIS FOG WILL AFFECT KAND OR KAVL. WILL KEEP FCST VFR FOR NOW AND
LET LATER SHIFTS SEE IF ANY TRENDS DEVELOP.
OUTLOOK...PREDOMINATE VFR WITH HIGH PRESSURE INTO THE FIRST PART OF
NEXT WEEK. EXPECTED AREAS OF MRNG FOG...MAINLY NEAR RIVERS AND
LAKES. COLD FRONT MOVES IN TUE WITH CHC SHWRS AND CIG/VSBY
RESTRICTIONS. FRONT MOVES EAST WED WITH VFR RETURNING.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JDL
NEAR TERM...RB/RWH
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...RWH
000
FXUS62 KCHS 071728
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1228 PM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE
WEEKEND. THE COMBINATION OF A STORM SYSTEM LIFTING OUT OF THE GULF
OF MEXICO AND A COLD FRONT APPROACHING FROM THE WEST WILL KEEP
THINGS UNSETTLED DURING THE EARLY TO MIDDLE PART OF NEXT WEEK.
HIGH PRESSURE WILL THEN BUILD BACK INTO THE REGION BY THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
VERY FEW CHANGES WERE MADE TO THE GRIDS AND TEXT PRODUCTS WITH THE
MORNING UPDATE. QUIET WEATHER WILL DOMINATE AGAIN TODAY AS HIGH
PRESSURE SHIFTS SLOWLY OFF THE NORTH CAROLINA COAST. EXPECT
SLIGHTLY WARMER TEMPERATURES THIS AFTERNOON WITH HIGHS IN THE
LOWER 70S AWAY FROM THE BEACHES. A DEVELOPING ONSHORE FLOW WILL
LIMIT TEMPERATURES ALONG THE BEACH FRONT TO THE UPPER 60S WITH A
FEW MID 60S ALONG A FEW OF THE CHARLESTON COUNTY BEACHES. SUNNY TO
MOSTLY SUNNY SKIES WILL PREVAIL WITH ONLY PATCHY CUMULUS EXPECTED
TO DEVELOP WITH THE ONSHORE FLOW.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
UPPER LEVEL RIDGING WILL EXPAND OVER THE SOUTHEASTERN U.S. TONIGHT
AS HIGH PRESSURE AT THE SURFACE LINGERS OVER THE WESTERN ATLANTIC.
A SYNOPTIC ONSHORE FLOW IN THE LOW LEVELS OF THE ATMOSPHERE WILL
CONTINUE TO ADVECT SOME MOISTURE INLAND...BUT TO WHAT EXTENT IS
STILL UNCERTAIN. EITHER WAY DO NOT ANTICIPATE MUCH IN THE WAY OF
CLOUD COVER...WITH THE GREATEST COVERAGE ACROSS NORTH COASTAL
GEORGIA. THE ONSHORE FLOW AND MODERATING AIRMASS WILL NOT ALLOW
TEMPERATURES TO FALL AS SIGNIFICANTLY AS THE PAST COUPLE OF
MORNINGS...WITH LOW TEMPERATURES EXPECTED TO RANGE FROM THE LOWER
40S WELL INLAND TO THE UPPER 40S TOWARD THE COAST. AREAS ALONG THE
IMMEDIATE COAST WILL BE SIGNIFICANTLY WARMER.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
FAIRLY GOOD MODEL AGREEMENT INTO MONDAY LEADS TO HIGHER THAN
NORMAL FORECAST CONFIDENCE...THEN CONFIDENCE LOWERS A BIT THROUGH
MID WEEK DUE TO THE UNCERTAINTY WITH REGARD TO TROPICAL CYCLONE
IDA...OR ITS REMNANTS.
HIGH PRESSURE TO THE NORTH WILL CONTINUE THROUGH MONDAY BEFORE THE
THE HIGH BEGINS TO BREAK DOWN DUE TO THE APPROACH OF A SURFACE AREA
OF LOW PRESSURE FROM THE SOUTH AND AN UPPER LEVEL TROUGH FROM THE
WEST. A STRONG AREA OF HIGH PRESSURE BUILDING IN QUICKLY BEHIND THE
DEPARTING TROUGH TUE NIGHT SHOULD HELP KEEP THE LOW /TC IDA OR ITS
REMNANTS/ SOUTH AND EAST OF THE AREA. HOWEVER...AN INCREASE IN
TROPICAL MOISTURE OVER THE SOUTHEAST ALONG WITH THE APPROACHING
FRONT WILL YIELD INCREASING RAIN CHANCES FROM MONDAY NIGHT AND
TUESDAY. DRIER WEATHER IS THEN EXPECTED BEHIND THE COLD FRONT
WEDNESDAY AND THURSDAY. THE TREND IS FOR LOWER POPS WEDNESDAY SO
HAVE FOLLOWED SUITE BUT DID NOT PULL POPS COMPLETELY JUST YET.
ALSO...AS PWATS INCREASE TO AROUND 2 INCHES /WHICH IS ABOUT 2
STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF YEAR/ AND THE AREA
BECOMES SITUATED IN A FAVORABLE JET ENTRANCE REGION...THERE IS A
CHANCE FOR AT LEAST A FEW INCHES OF RAIN FROM THIS EVENT.
TEMPERATURES WILL GENERALLY BE NEAR NORMAL THROUGH THE PERIOD EXCEPT
FOR ABOVE NORMAL TEMPERATURES SUNDAY...MONDAY AND FRIDAY.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH 18Z SUNDAY FOR KCHS
AND KSAV. WITH A PERSISTENT ONSHORE FLOW AND MODELS SHOWING A SLIGHT
INCREASE IN LOW LEVEL MOISTURE...EXPECT A FEW CUMULUS TO DEVELOP
ACROSS THE AREA THIS AFTERNOON. MAINLY CLEAR SKIES AND CALM WINDS
WILL PREVAIL OVERNIGHT BUT LOW LEVEL MOISTURE WILL CONTINUE TO
ADVECT INTO THE AREA AS AN ONSHORE FLOW REDEVELOPS SUNDAY AFTERNOON.
EXTENDED AVIATION OUTLOOK...VFR CONDITIONS WILL PREVAIL THROUGH
MONDAY. THE COMBINATION OF A STORM SYSTEM LIFTING NORTHEAST OUT OF
THE GULF OF MEXICO AND A COLD FRONT APPROACHING FROM THE WEST WILL
RESULT IN UNSETTLED WEATHER AND THE POTENTIAL FOR MVFR OR IFR
CONDITIONS MONDAY NIGHT THROUGH WEDNESDAY. LLWS IS ALSO POSSIBLE
WEDNESDAY MORNING.
&&
.MARINE...
HIGH PRESSURE WILL SHIFT OFFSHORE NORTH OF THE AREA TODAY...CAUSING
NORTHEAST WINDS TO SHIFT EAST THIS AFTERNOON. THE SURFACE PRESSURE
GRADIENT WILL NOT BE TIGHT ENOUGH TO SUPPORT WINDS ANY GREATER
THAN 10 KT ACROSS THE WATERS THROUGH THIS AFTERNOON. SEAS WILL
GENERALLY RANGE FROM 2-3 FT ACROSS THE NEARSHORE WATERS AND 3-4 FT
ACROSS THE OUTER GEORGIA WATERS.
HIGH PRESSURE WILL LINGER OVER THE WESTERN ATLANTIC TONIGHT...KEEPING
AN ONSHORE FLOW IN PLACE WITH WIND SPEEDS 15 KT OR LESS AND SEAS 4
FT OR LESS.
SUNDAY THROUGH WEDNESDAY...HIGH PRES WILL REMAIN N OF THE AREA EARLY
NEXT WEEK AS AN AREA OF LOW PRES /POSSIBLY TS IDA/ TRACKS N/NE OUT
OF THE GULF OF MEX. MEANWHILE...A COLD FRONT WILL PUSH ACROSS THE
AREA TUE/TUE NIGHT WHICH WILL KEEP THE LOW S AND E OF THE AREA.
HOWEVER...A VERY STRONG PRES GRADIENT WILL SET UP B/W THE LOW AND A
BUILDING HIGH PRES SYSTEM INLAND. SMALL CRAFT ADVISORIES ARE
EXPECTED ACROSS ALL WATERS BY TUE AND GALES ARE EVEN POSSIBLE
WED/WED NIGHT...ESPECIALLY ACROSS THE WATERS BEYOND 20 NM.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
000
FXUS62 KCAE 071726
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1226 PM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN IN CONTROL OF THE REGION THROUGH EARLY
NEXT WEEK. THIS WILL CONTINUE THE SUNNY SKIES AND SLIGHTLY WARMER
THAN NORMAL TEMPERATURES THROUGH MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL CONTINUE TO DOMINATE THE REGION WITH CLEAR
SKIES AND LIGHT WINDS THROUGH THE DAY. MAIN FOCUS REMAINS THE
POTENTIAL FOR FROST THROUGH 7AM THIS MORNING. TEMPERATURES AT MOST
LOCATIONS CURRENTLY IN THE MID 30S WITH TYPICALLY COOLER LOCATIONS
IN THE LOWER 30S. WITH DEWPOINTS ACROSS THE FORECAST AREA
GENERALLY IN THE MID 30S DO NOT EXPECT MUCH MORE COOLING THROUGH
DAYBREAK. WILL REMAIN WITH THE FROST ADVISORY THROUGH 7AM.
TEMPERATURES WILL QUICKLY WARM WITH SUNRISE AS SKIES WILL REMAIN
CLEAR THROUGH THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
SITUATION WILL REMAIN STATUS QUO THROUGH THE SHORT TERM AS
TEMPERATURES SLOWLY RISE A FEW DEGREES EACH DAY. THIS WILL ALSO
APPLY TO OVERNIGHT LOWS WHICH WILL END THE THREAT OF FROST. MONDAY
WILL SEE SOME CHANGE DURING THE AFTERNOON AS CLOUDS AHEAD OF THE
NEXT FRONT ALONG WITH SOME CLOUDS FROM TS IDA. EVEN WITH THE
INCREASING CLOUDS AT THE END OF THE SHORT TERM FORECAST DO NOT
EXPECT ANY RAIN UNTIL MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS IN GOOD AGREEMENT THROUGH MOST OF THE LONG TERM. MAIN ISSUE
IN THE LONG TERM WILL BE THE INTERACTION OF TS IDA AND THE NEXT
COLD FRONT MOVING THROUGH THE REGION TUESDAY NIGHT. CURRENTLY
EXPECT THE FRONT TO KEEP IDA AWAY FROM THE FORECAST AREA...HOWEVER
MOISTURE ASSOCIATED WITH IDA WILL MOVE INTO THE REGION MONDAY
NIGHT THROUGH TUESDAY NIGHT. HAVE INCREASED POPS FOR THIS PERIOD
WITH FEW OTHER CHANGES AS CONFIDENCE IN TIMING OF THE SYSTEMS IS
LOW. NO CHANGES MADE TO THE LONG TERM BEYOND TUESDAY NIGHT.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
DRY HIGH PRESSURE WILL REMAIN IN PLACE THROUGH THE TAF PERIOD.
EXPECT MAINLY VFR CONDITIONS THROUGH THE TAF PERIOD. THREAT FOR
FOG APPEARS HIGHER AT AGS AND OGB WHERE THE ADDED COOLING AND
MOISTURE ASSOCIATED WITH THE RIVER VALLEYS SUPPORT A PERIOD OF
MVFR OR IFR FOG DURING THE EARLY MORNING HOURS.
EXTENDED AVIATION OUTLOOK...WIDESPREAD CEILING AND VISIBILITY
RESTRICTIONS MAY OCCUR TUESDAY INTO WEDNESDAY ASSOCIATED WITH
ISENTROPIC LIFT.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...07
000
FXUS62 KGSP 071543
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1043 AM EST SAT NOV 7 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS EXPECTED TO MOVE INTO
THE CAROLINAS AND NORTH GEORGIA AHEAD OF A COLD FRONT TUESDAY...WITH
THE FRONT EXPECTED TO CROSS THE AREA ON TUESDAY NIGHT AND EARLY
WEDNESDAY. HIGH PRESSURE WILL THEN RETURN FOR THE LATER HALF OF NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPPER RIDGE CONTINUES TO BUILD OVER THE AREA TODAY WHILE CENTER OF
SFC HIGH MOVES INTO THE ATLANTIC. SFC RIDGING REMAINS OVER THE AREA
THOUGH. SOUTH TO SOUTHWEST WINDS PICK UP AS THICKNESSES RISE AND
CIRRUS MOVES TO OUR EAST. HIGHS SHOULD BE A FEW DEGREES HIGHER THAN
FRIDAY. CURRENT FCST HAS THIS COVERED WITH ONLY MINOR ADJUSTMENTS
NEEDED.
UPPER RIDGE CONTINUES TO BUILD TONIGHT WITH S-SW WINDS AT THE SFC.
EVEN THOUGH SKIES WILL BE MCLEAR OVERNIGHT...RISING THICKNESS WILL
KEEP TEMPS IN THE U30S-L40S ACROSS THE PIEDMONT WITH 30S IN THE MTNS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 225 AM SATURDAY...THE UPPER RIDGE WILL CONTINUE BUILD ALONG
THE EAST COAST THROUGH SUNDAY NIGHT...BEFORE BEGINNING A SLIGHT
EASTWARD PROGRESSION/BREAK DOWN BY THE END OF THE SHORT TERM. HIGH
MID-LEVEL HEIGHTS/INCREASED THICKNESS WILL RESULT IN VERY WARM MAXES
THROUGH THE PERIOD...WITH MANY AREAS OF THE PIEDMONT EXPECTED TO
REACH THE MID 70S SUNDAY AFTERNOON. EVEN THE MTN VALLEYS COULD SEE
THE LOWER 70S. MUCH OF THE SAME IS EXPECTED ON MONDAY...ALTHOUGH
INCREASING HIGH CLOUDS MAY MODERATE TEMPS JUST A BIT. ALTHOUGH GOOD
RADIATIONAL COOLING CONDITIONS SHOULD ALLOW LOWS TO SETTLE TO NEAR
NORMAL LEVELS...FROST/FREEZE WILL NOT BE A CONCERN DURING THIS
TIME.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 230 AM SATURDAY...WEATHER BECOMES MORE ACTIVE DURING THE EARLY
PART OF THE MEDIUM RANGE...AS A SW TROUGH DIGGING ACROSS THE UPPER
MIDWEST RESULTS IN COMPLETE BREAKDOWN/EASTWARD PROGRESSION OF THE
UPPER RIDGE. MEANWHILE...TROPICAL STORM IDA IS EXPECTED TO BE MOVING
NORTHEAST ACROSS THE CENTRAL/NORTHERN GULF EARLY TUESDAY. THE GFS
AND ECMWF ARE IN VERY GOOD AGREEMENT IN SPREADING MOISTURE
ASSOCIATED WITH IDA INTO THE CAROLINAS TUESDAY...BEFORE THE UPPER
TROUGH AND ASSOCIATED COLD FRONT SWEEP IT OFF THE SOUTHEAST COAST
EARLY WEDNESDAY. THE NAM IS NOT AS EXCITED ABOUT THIS SCENARIO.
CONSIDERING ITS TRACK RECORD AND SUPPORT FROM OTHER MODELS...IT
APPEARS THE GFS IS THE WAY TO GO WITH THIS FORECAST. HOWEVER...THERE
IS STILL SUFFICIENT UNCERTAINTY TO CONTINUE WITH A CONSERVATIVE POP
FORECAST. WE WILL MAINTAIN AN AREA OF LIKELY POPS ACROSS THE SOUTH
TUESDAY...BUT HAVE ACTUALLY TEMPERED POPS A BIT ACROSS THE NORTH.
AFTER LINGERING TOKEN CHANCE POPS ACROSS THE AREA TUE NIGHT...THE
REMAINDER OF THE EXTENDED PERIODS APPEAR TO BE DOMINATED BY DRY/COOL
HIGH PRESSURE.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
AT KCLT AND ELSEWHERE...FEW TO SCT250 WITH LGT S TO SW WIND...
INCRSNG TO 5-10 KTS THRU THE AFTN...THEN LGT AFTER SUNSET.
OUTLOOK...PREDOMINATE VFR WITH HIGH PRESSURE INTO THE FIRST PART OF
NEXT WEEK. EXPECTED AREAS OF MRNG FOG...MAINLY NEAR RIVERS AND
LAKES. COLD FRONT MOVES IN TUE WITH CHC SHWRS AND CIG/VSBY
RESTRICTIONS.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JDL
NEAR TERM...RB/RWH
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...RB
000
FXUS62 KCHS 071446
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
946 AM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE
WEEKEND. THE COMBINATION OF A STORM SYSTEM LIFTING OUT OF THE GULF
OF MEXICO AND A COLD FRONT APPROACHING FROM THE WEST WILL KEEP
THINGS UNSETTLED DURING THE EARLY TO MIDDLE PART OF NEXT WEEK.
HIGH PRESSURE WILL THEN BUILD BACK INTO THE REGION BY THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
VERY FEW CHANGES WERE MADE TO THE GRIDS AND TEXT PRODUCTS WITH THE
MORNING UPDATE. QUIET WEATHER WILL DOMINATE AGAIN TODAY AS HIGH
PRESSURE SHIFTS SLOWLY OFF THE NORTH CAROLINA COAST. EXPECT
SLIGHTLY WARMER TEMPERATURES THIS AFTERNOON WITH HIGHS IN THE
LOWER 70S AWAY FROM THE BEACHES. A DEVELOPING ONSHORE FLOW WILL
LIMIT TEMPERATURES ALONG THE BEACH FRONT TO THE UPPER 60S WITH A
FEW MID 60S ALONG A FEW OF THE CHARLESTON COUNTY BEACHES. SUNNY TO
MOSTLY SUNNY SKIES WILL PREVAIL WITH ONLY PATCHY CUMULUS EXPECTED
TO DEVELOP WITH THE ONSHORE FLOW.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
UPPER LEVEL RIDGING WILL EXPAND OVER THE SOUTHEASTERN U.S. TONIGHT
AS HIGH PRESSURE AT THE SURFACE LINGERS OVER THE WESTERN ATLANTIC.
A SYNOPTIC ONSHORE FLOW IN THE LOW LEVELS OF THE ATMOSPHERE WILL
CONTINUE TO ADVECT SOME MOISTURE INLAND...BUT TO WHAT EXTENT IS
STILL UNCERTAIN. EITHER WAY DO NOT ANTICIPATE MUCH IN THE WAY OF
CLOUD COVER...WITH THE GREATEST COVERAGE ACROSS NORTH COASTAL
GEORGIA. THE ONSHORE FLOW AND MODERATING AIRMASS WILL NOT ALLOW
TEMPERATURES TO FALL AS SIGNIFICANTLY AS THE PAST COUPLE OF
MORNINGS...WITH LOW TEMPERATURES EXPECTED TO RANGE FROM THE LOWER
40S WELL INLAND TO THE UPPER 40S TOWARD THE COAST. AREAS ALONG THE
IMMEDIATE COAST WILL BE SIGNIFICANTLY WARMER.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
FAIRLY GOOD MODEL AGREEMENT INTO MONDAY LEADS TO HIGHER THAN
NORMAL FORECAST CONFIDENCE...THEN CONFIDENCE LOWERS A BIT THROUGH
MID WEEK DUE TO THE UNCERTAINTY WITH REGARD TO TROPICAL CYCLONE
IDA...OR ITS REMNANTS.
HIGH PRESSURE TO THE NORTH WILL CONTINUE THROUGH MONDAY BEFORE THE
THE HIGH BEGINS TO BREAK DOWN DUE TO THE APPROACH OF A SURFACE AREA
OF LOW PRESSURE FROM THE SOUTH AND AN UPPER LEVEL TROUGH FROM THE
WEST. A STRONG AREA OF HIGH PRESSURE BUILDING IN QUICKLY BEHIND THE
DEPARTING TROUGH TUE NIGHT SHOULD HELP KEEP THE LOW /TC IDA OR ITS
REMNANTS/ SOUTH AND EAST OF THE AREA. HOWEVER...AN INCREASE IN
TROPICAL MOISTURE OVER THE SOUTHEAST ALONG WITH THE APPROACHING
FRONT WILL YIELD INCREASING RAIN CHANCES FROM MONDAY NIGHT AND
TUESDAY. DRIER WEATHER IS THEN EXPECTED BEHIND THE COLD FRONT
WEDNESDAY AND THURSDAY. THE TREND IS FOR LOWER POPS WEDNESDAY SO
HAVE FOLLOWED SUITE BUT DID NOT PULL POPS COMPLETELY JUST YET.
ALSO...AS PWATS INCREASE TO AROUND 2 INCHES /WHICH IS ABOUT 2
STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF YEAR/ AND THE AREA
BECOMES SITUATED IN A FAVORABLE JET ENTRANCE REGION...THERE IS A
CHANCE FOR AT LEAST A FEW INCHES OF RAIN FROM THIS EVENT.
TEMPERATURES WILL GENERALLY BE NEAR NORMAL THROUGH THE PERIOD EXCEPT
FOR ABOVE NORMAL TEMPERATURES SUNDAY...MONDAY AND FRIDAY.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL AT KCHS AND KSAV THROUGH 12Z SUNDAY.
THE AIRMASS WILL REMAIN EXTREMELY DRY THROUGH THIS MORNING AT BOTH
TERMINALS...LEADING TO CLEAR SKIES. HOWEVER...A LOW LEVEL ONSHORE FLOW
COULD ADVECT A FEW STRATOCUMULUS ONSHORE DURING THE AFTERNOON. WINDS
WILL REMAIN BELOW 10 KT THROUGH THE FORECAST PERIOD.
EXTENDED AVIATION OUTLOOK...VFR CONDITIONS WILL PREVAIL THROUGH
MONDAY. THE COMBINATION OF A STORM SYSTEM LIFTING NORTHEAST OUT OF
THE GULF OF MEXICO AND A COLD FRONT APPROACHING FROM THE WEST WILL
RESULT IN UNSETTLED WEATHER AND THE POTENTIAL FOR MVFR OR IFR
CONDITIONS MONDAY NIGHT THROUGH WEDNESDAY. LLWS IS ALSO POSSIBLE
WEDNESDAY MORNING.
&&
.MARINE...
HIGH PRESSURE WILL SHIFT OFFSHORE NORTH OF THE AREA TODAY...CAUSING
NORTHEAST WINDS TO SHIFT EAST THIS AFTERNOON. THE SURFACE PRESSURE
GRADIENT WILL NOT BE TIGHT ENOUGH TO SUPPORT WINDS ANY GREATER
THAN 10 KT ACROSS THE WATERS THROUGH THIS AFTERNOON. SEAS WILL
GENERALLY RANGE FROM 2-3 FT ACROSS THE NEARSHORE WATERS AND 3-4 FT
ACROSS THE OUTER GEORGIA WATERS.
HIGH PRESSURE WILL LINGER OVER THE WESTERN ATLANTIC TONIGHT...KEEPING
AN ONSHORE FLOW IN PLACE WITH WIND SPEEDS 15 KT OR LESS AND SEAS 4
FT OR LESS.
SUNDAY THROUGH WEDNESDAY...HIGH PRES WILL REMAIN N OF THE AREA EARLY
NEXT WEEK AS AN AREA OF LOW PRES /POSSIBLY TS IDA/ TRACKS N/NE OUT
OF THE GULF OF MEX. MEANWHILE...A COLD FRONT WILL PUSH ACROSS THE
AREA TUE/TUE NIGHT WHICH WILL KEEP THE LOW S AND E OF THE AREA.
HOWEVER...A VERY STRONG PRES GRADIENT WILL SET UP B/W THE LOW AND A
BUILDING HIGH PRES SYSTEM INLAND. SMALL CRAFT ADVISORIES ARE
EXPECTED ACROSS ALL WATERS BY TUE AND GALES ARE EVEN POSSIBLE
WED/WED NIGHT...ESPECIALLY ACROSS THE WATERS BEYOND 20 NM.
&&
.TIDES/COASTAL FLOODING...
TIDAL DEPARTURES WILL REMAIN ELEVATED THIS MORNING DUE TO A
PERSISTENT NORTHEAST FLOW...BUT CURRENT TRENDS SUGGEST TIDE LEVELS
WILL REMAIN BELOW ADVISORY THRESHOLDS. THERE COULD STILL BE SOME
VERY MINOR FLOODING IN PARTS OF DOWNTOWN CHARLESTON...BUT NOT
ENOUGH TO JUSTIFY THE ISSUANCE OF A COASTAL FLOOD ADVISORY.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
000
FXUS62 KGSP 071418
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
918 AM EST SAT NOV 7 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS EXPECTED TO MOVE INTO
THE CAROLINAS AND NORTH GEORGIA AHEAD OF A COLD FRONT TUESDAY...WITH
THE FRONT EXPECTED TO CROSS THE AREA ON TUESDAY NIGHT AND EARLY
WEDNESDAY. HIGH PRESSURE WILL THEN RETURN FOR THE LATER HALF OF NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATED FORECAST TO REMOVE FROST/FREEZE PRODUCTS AND CAPTURE CURRENT
TEMP/DEW POINT AND CLOUD TRENDS. OTHERWISE...FORECAST REASONING
REMAINS THE SAME.
PREVIOUS DISCUSSION...UPPER RIDGE AXIS CONTINUES TO BUILD OVERHEAD
WITH THIN HIGH CLOUDS AND CALM TO LGT S WINDS THIS MRNG. AFTER A
COLD START...SEE FREEZE WARNING/FROST ADVISORY FOR PIEDMONT
AREAS...TEMPS WILL WARM QUICKLY TODAY. HIGHS SHOULD REACH INTO THE
M-U60S ACROSS THE PIEDMONT WITH L-M60S MTNS. UPPER RIDGE CONTINUES
TO BUILD TONIGHT WITH S-SW WINDS AT THE SFC. EVEN THOUGH SKIES WILL
BE MCLEAR OVERNIGHT...RISING THICKNESS WILL KEEP TEMPS IN THE
U30S-L40S ACROSS THE PIEDMONT WITH 30S IN THE MTNS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 225 AM SATURDAY...THE UPPER RIDGE WILL CONTINUE BUILD ALONG
THE EAST COAST THROUGH SUNDAY NIGHT...BEFORE BEGINNING A SLIGHT
EASTWARD PROGRESSION/BREAK DOWN BY THE END OF THE SHORT TERM. HIGH
MID-LEVEL HEIGHTS/INCREASED THICKNESS WILL RESULT IN VERY WARM MAXES
THROUGH THE PERIOD...WITH MANY AREAS OF THE PIEDMONT EXPECTED TO
REACH THE MID 70S SUNDAY AFTERNOON. EVEN THE MTN VALLEYS COULD SEE
THE LOWER 70S. MUCH OF THE SAME IS EXPECTED ON MONDAY...ALTHOUGH
INCREASING HIGH CLOUDS MAY MODERATE TEMPS JUST A BIT. ALTHOUGH GOOD
RADIATIONAL COOLING CONDITIONS SHOULD ALLOW LOWS TO SETTLE TO NEAR
NORMAL LEVELS...FROST/FREEZE WILL NOT BE A CONCERN DURING THIS
TIME.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 230 AM SATURDAY...WEATHER BECOMES MORE ACTIVE DURING THE EARLY
PART OF THE MEDIUM RANGE...AS A SW TROUGH DIGGING ACROSS THE UPPER
MIDWEST RESULTS IN COMPLETE BREAKDOWN/EASTWARD PROGRESSION OF THE
UPPER RIDGE. MEANWHILE...TROPICAL STORM IDA IS EXPECTED TO BE MOVING
NORTHEAST ACROSS THE CENTRAL/NORTHERN GULF EARLY TUESDAY. THE GFS
AND ECMWF ARE IN VERY GOOD AGREEMENT IN SPREADING MOISTURE
ASSOCIATED WITH IDA INTO THE CAROLINAS TUESDAY...BEFORE THE UPPER
TROUGH AND ASSOCIATED COLD FRONT SWEEP IT OFF THE SOUTHEAST COAST
EARLY WEDNESDAY. THE NAM IS NOT AS EXCITED ABOUT THIS SCENARIO.
CONSIDERING ITS TRACK RECORD AND SUPPORT FROM OTHER MODELS...IT
APPEARS THE GFS IS THE WAY TO GO WITH THIS FORECAST. HOWEVER...THERE
IS STILL SUFFICIENT UNCERTAINTY TO CONTINUE WITH A CONSERVATIVE POP
FORECAST. WE WILL MAINTAIN AN AREA OF LIKELY POPS ACROSS THE SOUTH
TUESDAY...BUT HAVE ACTUALLY TEMPERED POPS A BIT ACROSS THE NORTH.
AFTER LINGERING TOKEN CHANCE POPS ACROSS THE AREA TUE NIGHT...THE
REMAINDER OF THE EXTENDED PERIODS APPEAR TO BE DOMINATED BY DRY/COOL
HIGH PRESSURE.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
AT KCLT AND ELSEWHERE...FEW TO SCT250 WITH LGT S TO SW WIND...
INCRSNG TO 5-10 KTS THRU THE AFTN...THEN LGT AFTER SUNSET.
OUTLOOK...PREDOMINATE VFR WITH HIGH PRESSURE INTO THE FIRST PART OF
NEXT WEEK. EXPECTED AREAS OF MRNG FOG...MAINLY NEAR RIVERS AND
LAKES. COLD FRONT MOVES IN TUE WITH CHC SHWRS AND CIG/VSBY
RESTRICTIONS.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JDL
NEAR TERM...RB/RWH
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...RB
000
FXUS62 KCHS 071247
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
747 AM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE
WEEKEND. THE COMBINATION OF A STORM SYSTEM LIFTING OUT OF THE GULF
OF MEXICO AND A COLD FRONT APPROACHING FROM THE WEST WILL KEEP
THINGS UNSETTLED DURING THE EARLY TO MIDDLE PART OF NEXT WEEK.
HIGH PRESSURE WILL THEN BUILD BACK INTO THE REGION BY THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SURFACE HIGH PRESSURE WILL CONTINUE TO EXTEND OVER THE AREA TODAY
AS ITS CENTER GRADUALLY MOVES OFF THE COAST OF NORTH CAROLINA AND
INTO THE WESTERN ATLANTIC. MEANWHILE...HEIGHTS WILL RISE ACROSS THE
REGION AS AN UPPER LEVEL RIDGE EXPANDS EASTWARD FROM THE DEEP SOUTH.
ANTICYCLONIC FLOW AROUND THE SURFACE HIGH PRESSURE SYSTEM WILL
RESULT IN A LOW LEVEL ONSHORE FLOW TODAY. THIS COULD ADVECT JUST
ENOUGH MOISTURE INLAND TO ALLOW FOR SOME STRATOCUMULUS DEVELOPMENT
THIS AFTERNOON...BUT OVERALL SKIES WILL BE SUNNY OR MOSTLY SUNNY.
THE AIRMASS WILL BEGIN TO MODIFY TODAY AS LOW-LEVEL THICKNESS VALUES
SLOWLY INCREASE...GENERALLY SUPPORTING HIGHS IN THE LOWER 70S
ACROSS THE AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
UPPER LEVEL RIDGING WILL EXPAND OVER THE SOUTHEASTERN U.S. TONIGHT
AS HIGH PRESSURE AT THE SURFACE LINGERS OVER THE WESTERN ATLANTIC.
A SYNOPTIC ONSHORE FLOW IN THE LOW LEVELS OF THE ATMOSPHERE WILL
CONTINUE TO ADVECT SOME MOISTURE INLAND...BUT TO WHAT EXTENT IS
STILL UNCERTAIN. EITHER WAY DO NOT ANTICIPATE MUCH IN THE WAY OF
CLOUD COVER...WITH THE GREATEST COVERAGE ACROSS NORTH COASTAL
GEORGIA. THE ONSHORE FLOW AND MODERATING AIRMASS WILL NOT ALLOW
TEMPERATURES TO FALL AS SIGNIFICANTLY AS THE PAST COUPLE OF
MORNINGS...WITH LOW TEMPERATURES EXPECTED TO RANGE FROM THE LOWER
40S WELL INLAND TO THE UPPER 40S TOWARD THE COAST. AREAS ALONG THE
IMMEDIATE COAST WILL BE SIGNIFICANTLY WARMER.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
FAIRLY GOOD MODEL AGREEMENT INTO MONDAY LEADS TO HIGHER THAN
NORMAL FORECAST CONFIDENCE...THEN CONFIDENCE LOWERS A BIT THROUGH
MID WEEK DUE TO THE UNCERTAINTY WITH REGARD TO TROPICAL CYCLONE
IDA...OR ITS REMNANTS.
HIGH PRESSURE TO THE NORTH WILL CONTINUE THROUGH MONDAY BEFORE THE
THE HIGH BEGINS TO BREAK DOWN DUE TO THE APPROACH OF A SURFACE AREA
OF LOW PRESSURE FROM THE SOUTH AND AN UPPER LEVEL TROUGH FROM THE
WEST. A STRONG AREA OF HIGH PRESSURE BUILDING IN QUICKLY BEHIND THE
DEPARTING TROUGH TUE NIGHT SHOULD HELP KEEP THE LOW /TC IDA OR ITS
REMNANTS/ SOUTH AND EAST OF THE AREA. HOWEVER...AN INCREASE IN
TROPICAL MOISTURE OVER THE SOUTHEAST ALONG WITH THE APPROACHING
FRONT WILL YIELD INCREASING RAIN CHANCES FROM MONDAY NIGHT AND
TUESDAY. DRIER WEATHER IS THEN EXPECTED BEHIND THE COLD FRONT
WEDNESDAY AND THURSDAY. THE TREND IS FOR LOWER POPS WEDNESDAY SO
HAVE FOLLOWED SUITE BUT DID NOT PULL POPS COMPLETELY JUST YET.
ALSO...AS PWATS INCREASE TO AROUND 2 INCHES /WHICH IS ABOUT 2
STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF YEAR/ AND THE AREA
BECOMES SITUATED IN A FAVORABLE JET ENTRANCE REGION...THERE IS A
CHANCE FOR AT LEAST A FEW INCHES OF RAIN FROM THIS EVENT.
TEMPERATURES WILL GENERALLY BE NEAR NORMAL THROUGH THE PERIOD EXCEPT
FOR ABOVE NORMAL TEMPERATURES SUNDAY...MONDAY AND FRIDAY.
&&
.AVIATION /13Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL AT KCHS AND KSAV THROUGH 12Z SUNDAY.
THE AIRMASS WILL REMAIN EXTREMELY DRY THROUGH THIS MORNING AT BOTH
TERMINALS...LEADING TO CLEAR SKIES. HOWEVER...A LOW LEVEL ONSHORE FLOW
COULD ADVECT A FEW STRATOCUMULUS ONSHORE DURING THE AFTERNOON. WINDS
WILL REMAIN BELOW 10 KT THROUGH THE FORECAST PERIOD.
EXTENDED AVIATION OUTLOOK...VFR CONDITIONS WILL PREVAIL THROUGH
MONDAY. THE COMBINATION OF A STORM SYSTEM LIFTING NORTHEAST OUT OF
THE GULF OF MEXICO AND A COLD FRONT APPROACHING FROM THE WEST WILL
RESULT IN UNSETTLED WEATHER AND THE POTENTIAL FOR MVFR OR IFR
CONDITIONS MONDAY NIGHT THROUGH WEDNESDAY. LLWS IS ALSO POSSIBLE
WEDNESDAY MORNING.
&&
.MARINE...
HIGH PRESSURE WILL SHIFT OFFSHORE NORTH OF THE AREA TODAY...CAUSING
NORTHEAST WINDS TO SHIFT EAST THIS AFTERNOON. THE SURFACE PRESSURE
GRADIENT WILL NOT BE TIGHT ENOUGH TO SUPPORT WINDS ANY GREATER
THAN 10-15 KT ACROSS THE WATERS THROUGH THIS AFTERNOON. SEAS WILL
GENERALLY RANGE FROM 2-3 FT ACROSS THE NEARSHORE WATERS AND 3-4 FT
ACROSS THE OUTER GEORGIA WATERS.
HIGH PRESSURE WILL LINGER OVER THE WESTERN ATLANTIC TONIGHT...KEEPING
AN ONSHORE FLOW IN PLACE WITH WIND SPEEDS 15 KT OR LESS AND SEAS 4
FT OR LESS.
SUNDAY THROUGH WEDNESDAY...HIGH PRES WILL REMAIN N OF THE AREA EARLY
NEXT WEEK AS AN AREA OF LOW PRES /POSSIBLY TS IDA/ TRACKS N/NE OUT
OF THE GULF OF MEX. MEANWHILE...A COLD FRONT WILL PUSH ACROSS THE
AREA TUE/TUE NIGHT WHICH WILL KEEP THE LOW S AND E OF THE AREA.
HOWEVER...A VERY STRONG PRES GRADIENT WILL SET UP B/W THE LOW AND A
BUILDING HIGH PRES SYSTEM INLAND. SMALL CRAFT ADVISORIES ARE
EXPECTED ACROSS ALL WATERS BY TUE AND GALES ARE EVEN POSSIBLE
WED/WED NIGHT...ESPECIALLY ACROSS THE WATERS BEYOND 20 NM.
&&
.TIDES/COASTAL FLOODING...
TIDAL DEPARTURES WILL REMAIN ELEVATED THIS MORNING DUE TO A
PERSISTENT NORTHEAST FLOW. THE POSSIBILITY OF COASTAL FLOODING
ALONG PARTS OF THE SOUTHERN SOUTH CAROLINA COAST WILL REMAIN IN
THE HAZARDOUS WEATHER OUTLOOK AS ANOTHER COASTAL FLOOD ADVISORY FOR
SHALLOW COASTAL FLOODING MAY BE NEEDED.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
JAQ/RJB
000
FXUS62 KCHS 071130
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
630 AM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE
WEEKEND. THE COMBINATION OF A STORM SYSTEM LIFTING OUT OF THE GULF
OF MEXICO AND A COLD FRONT APPROACHING FROM THE WEST WILL KEEP
THINGS UNSETTLED DURING THE EARLY TO MIDDLE PART OF NEXT WEEK.
HIGH PRESSURE WILL THEN BUILD BACK INTO THE REGION BY THURSDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SURFACE HIGH PRESSURE WILL CONTINUE TO EXTEND OVER THE AREA TODAY
AS ITS CENTER GRADUALLY MOVES OFF THE COAST OF NORTH CAROLINA AND
INTO THE WESTERN ATLANTIC. MEANWHILE...HEIGHTS WILL RISE ACROSS THE
REGION AS AN UPPER LEVEL RIDGE EXPANDS EASTWARD FROM THE DEEP SOUTH.
AN EXTREMELY DRY AIRMASS...LEADING TO CLEAR SKIES...AND CALM WINDS
EARLY THIS MORNING HAVE RESULTED IN IDEAL RADIATIONAL COOLING
CONDITIONS. SCATTERED FROST IS EXPECTED FOR MANY INLAND LOCATIONS
ACROSS SOUTHERN SOUTH CAROLINA AND SOUTHEAST GEORGIA...THUS NO
CHANGES PLANNED TO THE ONGOING FROST ADVISORY WHICH IS SET TO
EXPIRE AT 8 AM THIS MORNING.
ANTICYCLONIC FLOW AROUND THE SURFACE HIGH PRESSURE SYSTEM WILL
RESULT IN A LOW LEVEL ONSHORE FLOW TODAY. THIS COULD ADVECT JUST
ENOUGH MOISTURE INLAND TO ALLOW FOR SOME STRATOCUMULUS DEVELOPMENT
THIS AFTERNOON...BUT OVERALL SKIES WILL BE SUNNY OR MOSTLY SUNNY.
THE AIRMASS WILL BEGIN TO MODIFY TODAY AS LOW-LEVEL THICKNESS VALUES
SLOWLY INCREASE...GENERALLY SUPPORTING HIGHS IN THE LOWER 70S
ACROSS THE AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
UPPER LEVEL RIDGING WILL EXPAND OVER THE SOUTHEASTERN U.S. TONIGHT
AS HIGH PRESSURE AT THE SURFACE LINGERS OVER THE WESTERN ATLANTIC.
A SYNOPTIC ONSHORE FLOW IN THE LOW LEVELS OF THE ATMOSPHERE WILL
CONTINUE TO ADVECT SOME MOISTURE INLAND...BUT TO WHAT EXTENT IS
STILL UNCERTAIN. EITHER WAY DO NOT ANTICIPATE MUCH IN THE WAY OF
CLOUD COVER...WITH THE GREATEST COVERAGE ACROSS NORTH COASTAL
GEORGIA. THE ONSHORE FLOW AND MODERATING AIRMASS WILL NOT ALLOW
TEMPERATURES TO FALL AS SIGNIFICANTLY AS THE PAST COUPLE OF
MORNINGS...WITH LOW TEMPERATURES EXPECTED TO RANGE FROM THE LOWER
40S WELL INLAND TO THE UPPER 40S TOWARD THE COAST. AREAS ALONG THE
IMMEDIATE COAST WILL BE SIGNIFICANTLY WARMER.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
FAIRLY GOOD MODEL AGREEMENT INTO MONDAY LEADS TO HIGHER THAN
NORMAL FORECAST CONFIDENCE...THEN CONFIDENCE LOWERS A BIT THROUGH
MID WEEK DUE TO THE UNCERTAINTY WITH REGARD TO TROPICAL CYCLONE
IDA...OR ITS REMNANTS.
HIGH PRESSURE TO THE NORTH WILL CONTINUE THROUGH MONDAY BEFORE THE
THE HIGH BEGINS TO BREAK DOWN DUE TO THE APPROACH OF A SURFACE AREA
OF LOW PRESSURE FROM THE SOUTH AND AN UPPER LEVEL TROUGH FROM THE
WEST. A STRONG AREA OF HIGH PRESSURE BUILDING IN QUICKLY BEHIND THE
DEPARTING TROUGH TUE NIGHT SHOULD HELP KEEP THE LOW /TC IDA OR ITS
REMNANTS/ SOUTH AND EAST OF THE AREA. HOWEVER...AN INCREASE IN
TROPICAL MOISTURE OVER THE SOUTHEAST ALONG WITH THE APPROACHING
FRONT WILL YIELD INCREASING RAIN CHANCES FROM MONDAY NIGHT AND
TUESDAY. DRIER WEATHER IS THEN EXPECTED BEHIND THE COLD FRONT
WEDNESDAY AND THURSDAY. THE TREND IS FOR LOWER POPS WEDNESDAY SO
HAVE FOLLOWED SUITE BUT DID NOT PULL POPS COMPLETELY JUST YET.
ALSO...AS PWATS INCREASE TO AROUND 2 INCHES /WHICH IS ABOUT 2
STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF YEAR/ AND THE AREA
BECOMES SITUATED IN A FAVORABLE JET ENTRANCE REGION...THERE IS A
CHANCE FOR AT LEAST A FEW INCHES OF RAIN FROM THIS EVENT.
TEMPERATURES WILL GENERALLY BE NEAR NORMAL THROUGH THE PERIOD EXCEPT
FOR ABOVE NORMAL TEMPERATURES SUNDAY...MONDAY AND FRIDAY.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL AT KCHS AND KSAV THROUGH 12Z SUNDAY.
THE AIRMASS WILL REMAIN EXTREMELY DRY THROUGH THIS MORNING AT BOTH
TERMINALS...LEADING TO CLEAR SKIES. HOWEVER...A LOW LEVEL ONSHORE FLOW
COULD ADVECT A FEW STRATOCUMULUS ONSHORE DURING THE AFTERNOON. WINDS
WILL REMAIN BELOW 10 KT THROUGH THE FORECAST PERIOD.
EXTENDED AVIATION OUTLOOK...VFR CONDITIONS WILL PREVAIL THROUGH
MONDAY. THE COMBINATION OF A STORM SYSTEM LIFTING NORTHEAST OUT OF
THE GULF OF MEXICO AND A COLD FRONT APPROACHING FROM THE WEST WILL
RESULT IN UNSETTLED WEATHER AND THE POTENTIAL FOR MVFR OR IFR
CONDITIONS MONDAY NIGHT THROUGH WEDNESDAY. LLWS IS ALSO POSSIBLE
WEDNESDAY MORNING.
&&
.MARINE...
HIGH PRESSURE WILL SHIFT OFFSHORE NORTH OF THE AREA TODAY...CAUSING
NORTHEAST WINDS TO SHIFT EAST THIS AFTERNOON. THE SURFACE PRESSURE
GRADIENT WILL NOT BE TIGHT ENOUGH TO SUPPORT WINDS ANY GREATER
THAN 10-15 KT ACROSS THE WATERS THROUGH THIS AFTERNOON. SEAS WILL
GENERALLY RANGE FROM 2-3 FT ACROSS THE NEARSHORE WATERS AND 3-4 FT
ACROSS THE OUTER GEORGIA WATERS.
HIGH PRESSURE WILL LINGER OVER THE WESTERN ATLANTIC TONIGHT...KEEPING
AN ONSHORE FLOW IN PLACE WITH WIND SPEEDS 15 KT OR LESS AND SEAS 4
FT OR LESS.
SUNDAY THROUGH WEDNESDAY...HIGH PRES WILL REMAIN N OF THE AREA EARLY
NEXT WEEK AS AN AREA OF LOW PRES /POSSIBLY TS IDA/ TRACKS N/NE OUT
OF THE GULF OF MEX. MEANWHILE...A COLD FRONT WILL PUSH ACROSS THE
AREA TUE/TUE NIGHT WHICH WILL KEEP THE LOW S AND E OF THE AREA.
HOWEVER...A VERY STRONG PRES GRADIENT WILL SET UP B/W THE LOW AND A
BUILDING HIGH PRES SYSTEM INLAND. SMALL CRAFT ADVISORIES ARE
EXPECTED ACROSS ALL WATERS BY TUE AND GALES ARE EVEN POSSIBLE
WED/WED NIGHT...ESPECIALLY ACROSS THE WATERS BEYOND 20 NM.
&&
.TIDES/COASTAL FLOODING...
TIDAL DEPARTURES WILL REMAIN ELEVATED THIS MORNING DUE TO A
PERSISTENT NORTHEAST FLOW. THE POSSIBILITY OF COASTAL FLOODING
ALONG PARTS OF THE SOUTHERN SOUTH CAROLINA COAST WILL REMAIN IN
THE HAZARDOUS WEATHER OUTLOOK AS ANOTHER COASTAL FLOOD ADVISORY FOR
SHALLOW COASTAL FLOODING MAY BE NEEDED.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...FROST ADVISORY UNTIL 8 AM EST THIS MORNING FOR GAZ087-088-
099>101-114-115.
SC...FROST ADVISORY UNTIL 8 AM EST THIS MORNING FOR SCZ040-042>045-
047.
MARINE...NONE.
&&
$$
JAQ/RJB
000
FXUS62 KCAE 071126
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
626 AM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN IN CONTROL OF THE REGION THROUGH EARLY
NEXT WEEK. THIS WILL CONTINUE THE SUNNY SKIES AND SLIGHTLY WARMER
THAN NORMAL TEMPERATURES THROUGH MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL CONTINUE TO DOMINATE THE REGION WITH CLEAR
SKIES AND LIGHT WINDS THROUGH THE DAY. MAIN FOCUS REMAINS THE
POTENTIAL FOR FROST THROUGH 7AM THIS MORNING. TEMPERATURES AT MOST
LOCATIONS CURRENTLY IN THE MID 30S WITH TYPICALLY COOLER LOCATIONS
IN THE LOWER 30S. WITH DEWPOINTS ACROSS THE FORECAST AREA
GENERALLY IN THE MID 30S DO NOT EXPECT MUCH MORE COOLING THROUGH
DAYBREAK. WILL REMAIN WITH THE FROST ADVISORY THROUGH 7AM.
TEMPERATURES WILL QUICKLY WARM WITH SUNRISE AS SKIES WILL REMAIN
CLEAR THROUGH THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
SITUATION WILL REMAIN STATUS QUO THROUGH THE SHORT TERM AS
TEMPERATURES SLOWLY RISE A FEW DEGREES EACH DAY. THIS WILL ALSO
APPLY TO OVERNIGHT LOWS WHICH WILL END THE THREAT OF FROST. MONDAY
WILL SEE SOME CHANGE DURING THE AFTERNOON AS CLOUDS AHEAD OF THE
NEXT FRONT ALONG WITH SOME CLOUDS FROM TS IDA. EVEN WITH THE
INCREASING CLOUDS AT THE END OF THE SHORT TERM FORECAST DO NOT
EXPECT ANY RAIN UNTIL MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS IN GOOD AGREEMENT THROUGH MOST OF THE LONG TERM. MAIN ISSUE
IN THE LONG TERM WILL BE THE INTERACTION OF TS IDA AND THE NEXT
COLD FRONT MOVING THROUGH THE REGION TUESDAY NIGHT. CURRENTLY
EXPECT THE FRONT TO KEEP IDA AWAY FROM THE FORECAST AREA...HOWEVER
MOISTURE ASSOCIATED WITH IDA WILL MOVE INTO THE REGION MONDAY
NIGHT THROUGH TUESDAY NIGHT. HAVE INCREASED POPS FOR THIS PERIOD
WITH FEW OTHER CHANGES AS CONFIDENCE IN TIMING OF THE SYSTEMS IS
LOW. NO CHANGES MADE TO THE LONG TERM BEYOND TUESDAY NIGHT.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
DRY HIGH PRESSURE WILL REMAIN IN PLACE THROUGH THE TAF PERIOD.
EXPECT MAINLY VFR CONDITIONS THROUGH THE TAF PERIOD. EXCEPTIONS MAY
BE AT AGS AND OGB WHERE THE ADDED COOLING AND MOISTURE ASSOCIATED
WITH THE RIVER VALLEYS SUPPORT A PERIOD OF MVFR OR IFR FOG DURING
THE EARLY MORNING HOURS.
EXTENDED AVIATION OUTLOOK...WIDESPREAD CEILING AND VISIBILITY
RESTRICTIONS MAY OCCUR TUESDAY INTO WEDNESDAY ASSOCIATED WITH
ISENTROPIC LIFT.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...FROST ADVISORY UNTIL 7 AM EST THIS MORNING FOR SCZ015-016-018-
020>022-025>031-035>038-041.
GA...FROST ADVISORY UNTIL 7 AM EST THIS MORNING FOR GAZ040-063>065-
077.
&&
$$
000
FXUS62 KGSP 071106
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
606 AM EST SAT NOV 7 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS EXPECTED TO MOVE INTO
THE CAROLINAS AND NORTH GEORGIA AHEAD OF A COLD FRONT TUESDAY...WITH
THE FRONT EXPECTED TO CROSS THE AREA ON TUESDAY NIGHT AND EARLY
WEDNESDAY. HIGH PRESSURE WILL THEN RETURN FOR THE LATER HALF OF NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPPER RIDGE AXIS CONTINUES TO BUILD OVERHEAD WITH THIN HIGH CLOUDS
AND CALM TO LGT S WINDS THIS MRNG. AFTER A COLD START...SEE FREEZE
WARNING/FROST ADVISORY FOR PIEDMONT AREAS...TEMPS WILL WARM QUICKLY
TODAY. HIGHS SHOULD REACH INTO THE M-U60S ACROSS THE PIEDMONT WITH
L-M60S MTNS. UPPER RIDGE CONTINUES TO BUILD TONIGHT WITH S-SW WINDS
AT THE SFC. EVEN THOUGH SKIES WILL BE MCLEAR OVERNIGHT...RISING
THICKNESS WILL KEEP TEMPS IN THE U30S-L40S ACROSS THE PIEDMONT WITH
30S IN THE MTNS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 225 AM SATURDAY...THE UPPER RIDGE WILL CONTINUE BUILD ALONG
THE EAST COAST THROUGH SUNDAY NIGHT...BEFORE BEGINNING A SLIGHT
EASTWARD PROGRESSION/BREAK DOWN BY THE END OF THE SHORT TERM. HIGH
MID-LEVEL HEIGHTS/INCREASED THICKNESS WILL RESULT IN VERY WARM MAXES
THROUGH THE PERIOD...WITH MANY AREAS OF THE PIEDMONT EXPECTED TO
REACH THE MID 70S SUNDAY AFTERNOON. EVEN THE MTN VALLEYS COULD SEE
THE LOWER 70S. MUCH OF THE SAME IS EXPECTED ON MONDAY...ALTHOUGH
INCREASING HIGH CLOUDS MAY MODERATE TEMPS JUST A BIT. ALTHOUGH GOOD
RADIATIONAL COOLING CONDITIONS SHOULD ALLOW LOWS TO SETTLE TO NEAR
NORMAL LEVELS...FROST/FREEZE WILL NOT BE A CONCERN DURING THIS
TIME.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 230 AM SATURDAY...WEATHER BECOMES MORE ACTIVE DURING THE EARLY
PART OF THE MEDIUM RANGE...AS A SW TROUGH DIGGING ACROSS THE UPPER
MIDWEST RESULTS IN COMPLETE BREAKDOWN/EASTWARD PROGRESSION OF THE
UPPER RIDGE. MEANWHILE...TROPICAL STORM IDA IS EXPECTED TO BE MOVING
NORTHEAST ACROSS THE CENTRAL/NORTHERN GULF EARLY TUESDAY. THE GFS
AND ECMWF ARE IN VERY GOOD AGREEMENT IN SPREADING MOISTURE
ASSOCIATED WITH IDA INTO THE CAROLINAS TUESDAY...BEFORE THE UPPER
TROUGH AND ASSOCIATED COLD FRONT SWEEP IT OFF THE SOUTHEAST COAST
EARLY WEDNESDAY. THE NAM IS NOT AS EXCITED ABOUT THIS SCENARIO.
CONSIDERING ITS TRACK RECORD AND SUPPORT FROM OTHER MODELS...IT
APPEARS THE GFS IS THE WAY TO GO WITH THIS FORECAST. HOWEVER...THERE
IS STILL SUFFICIENT UNCERTAINTY TO CONTINUE WITH A CONSERVATIVE POP
FORECAST. WE WILL MAINTAIN AN AREA OF LIKELY POPS ACROSS THE SOUTH
TUESDAY...BUT HAVE ACTUALLY TEMPERED POPS A BIT ACROSS THE NORTH.
AFTER LINGERING TOKEN CHANCE POPS ACROSS THE AREA TUE NIGHT...THE
REMAINDER OF THE EXTENDED PERIODS APPEAR TO BE DOMINATED BY DRY/COOL
HIGH PRESSURE.
&&
.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
AT KCLT AND ELSEWHERE...FEW TO SCT250 WITH LGT S TO SW WIND...
INCRSNG TO 5-10 KTS THRU THE AFTN...THEN LGT AFTER SUNSET.
OUTLOOK...PREDOMINATE VFR WITH HIGH PRESSURE INTO THE FIRST PART OF
NEXT WEEK. EXPECTED AREAS OF MRNG FOG...MAINLY NEAR RIVERS AND
LAKES. COLD FRONT MOVES IN TUE WITH CHC SHWRS AND CIG/VSBY
RESTRICTIONS.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FROST ADVISORY UNTIL 9 AM EST THIS MORNING FOR GAZ018-026-028.
FREEZE WARNING UNTIL 9 AM EST THIS MORNING FOR GAZ029.
NC...FROST ADVISORY UNTIL 9 AM EST THIS MORNING FOR NCZ508-510.
FREEZE WARNING UNTIL 9 AM EST THIS MORNING FOR NCZ035>037-056-
057-068>072-082.
SC...FROST ADVISORY UNTIL 9 AM EST THIS MORNING FOR SCZ001>007-010.
FREEZE WARNING UNTIL 9 AM EST THIS MORNING FOR SCZ008-009-
011>014-019.
&&
$$
SYNOPSIS...JDL
NEAR TERM...RB
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...RB
000
FXUS62 KCAE 070855
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
355 AM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN IN CONTROL OF THE REGION THROUGH EARLY
NEXT WEEK. THIS WILL CONTINUE THE SUNNY SKIES AND SLIGHTLY WARMER
THAN NORMAL TEMPERATURES THROUGH MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HIGH PRESSURE WILL CONTINUE TO DOMINATE THE REGION WITH CLEAR
SKIES AND LIGHT WINDS THROUGH THE DAY. MAIN FOCUS REMAINS THE
POTENTIAL FOR FROST THROUGH 7AM THIS MORNING. TEMPERATURES AT MOST
LOCATIONS CURRENTLY IN THE MID 30S WITH TYPICALLY COOLER LOCATIONS
IN THE LOWER 30S. WITH DEWPOINTS ACROSS THE FORECAST AREA
GENERALLY IN THE MID 30S DO NOT EXPECT MUCH MORE COOLING THROUGH
DAYBREAK. WILL REMAIN WITH THE FROST ADVISORY THROUGH 7AM.
TEMPERATURES WILL QUICKLY WARM WITH SUNRISE AS SKIES WILL REMAIN
CLEAR THROUGH THE DAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
SITUATION WILL REMAIN STATUS QUO THROUGH THE SHORT TERM AS
TEMPERATURES SLOWLY RISE A FEW DEGREES EACH DAY. THIS WILL ALSO
APPLY TO OVERNIGHT LOWS WHICH WILL END THE THREAT OF FROST. MONDAY
WILL SEE SOME CHANGE DURING THE AFTERNOON AS CLOUDS AHEAD OF THE
NEXT FRONT ALONG WITH SOME CLOUDS FROM TS IDA. EVEN WITH THE
INCREASING CLOUDS AT THE END OF THE SHORT TERM FORECAST DO NOT
EXPECT ANY RAIN UNTIL MONDAY NIGHT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS IN GOOD AGREEMENT THROUGH MOST OF THE LONG TERM. MAIN ISSUE
IN THE LONG TERM WILL BE THE INTERACTION OF TS IDA AND THE NEXT
COLD FRONT MOVING THROUGH THE REGION TUESDAY NIGHT. CURRENTLY
EXPECT THE FRONT TO KEEP IDA AWAY FROM THE FORECAST AREA...HOWEVER
MOISTURE ASSOCIATED WITH IDA WILL MOVE INTO THE REGION MONDAY
NIGHT THROUGH TUESDAY NIGHT. HAVE INCREASED POPS FOR THIS PERIOD
WITH FEW OTHER CHANGES AS CONFIDENCE IN TIMING OF THE SYSTEMS IS
LOW. NO CHANGES MADE TO THE LONG TERM BEYOND TUESDAY NIGHT.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
DRY HIGH PRESSURE WILL REMAIN IN PLACE THROUGH THE TAF PERIOD. VFR
CONDITIONS SHOULD CONTINUE.
EXTENDED AVIATION OUTLOOK...WIDESPREAD CEILING AND VISIBILITY
RESTRICTIONS MAY OCCUR TUESDAY INTO WEDNESDAY ASSOCIATED WITH
ISENTROPIC LIFT.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...FROST ADVISORY UNTIL 7 AM EST THIS MORNING FOR SCZ015-016-018-
020>022-025>031-035>038-041.
GA...FROST ADVISORY UNTIL 7 AM EST THIS MORNING FOR GAZ040-063>065-
077.
&&
$$
000
FXUS62 KCHS 070819
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
319 AM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE
WEEKEND. THE COMBINATION OF A STORM SYSTEM LIFTING OUT OF THE GULF
OF MEXICO AND A COLD FRONT APPROACHING FROM THE WEST WILL KEEP
THINGS UNSETTLED DURING THE EARLY TO MIDDLE PART OF NEXT WEEK.
HIGH PRESSURE WILL THEN BUILD BACK INTO THE REGION BY THURSDAY.
&&
.NEAR TERM /THROUGH TODAY/...
SURFACE HIGH PRESSURE WILL CONTINUE TO EXTEND OVER THE AREA TODAY
AS ITS CENTER GRADUALLY MOVES OFF THE COAST OF NORTH CAROLINA AND
INTO THE WESTERN ATLANTIC. MEANWHILE...HEIGHTS WILL RISE ACROSS THE
REGION AS AN UPPER LEVEL RIDGE EXPANDS EASTWARD FROM THE DEEP SOUTH.
AN EXTREMELY DRY AIRMASS...LEADING TO CLEAR SKIES...AND CALM WINDS
EARLY THIS MORNING HAVE RESULTED IN IDEAL RADIATIONAL COOLING
CONDITIONS. SCATTERED FROST IS EXPECTED FOR MANY INLAND LOCATIONS
ACROSS SOUTHERN SOUTH CAROLINA AND SOUTHEAST GEORGIA...THUS NO
CHANGES PLANNED TO THE ONGOING FROST ADVISORY WHICH IS SET TO
EXPIRE AT 8 AM THIS MORNING.
ANTICYCLONIC FLOW AROUND THE SURFACE HIGH PRESSURE SYSTEM WILL
RESULT IN A LOW LEVEL ONSHORE FLOW TODAY. THIS COULD ADVECT JUST
ENOUGH MOISTURE INLAND TO ALLOW FOR SOME STRATOCUMULUS DEVELOPMENT
THIS AFTERNOON...BUT OVERALL SKIES WILL BE SUNNY OR MOSTLY SUNNY.
THE AIRMASS WILL BEGIN TO MODIFY TODAY AS LOW-LEVEL THICKNESS VALUES
SLOWLY INCREASE...GENERALLY SUPPORTING HIGHS IN THE LOWER 70S
ACROSS THE AREA.
&&
.SHORT TERM /TONIGHT/...
UPPER LEVEL RIDGING WILL EXPAND OVER THE SOUTHEASTERN U.S. TONIGHT
AS HIGH PRESSURE AT THE SURFACE LINGERS OVER THE WESTERN ATLANTIC.
A SYNOPTIC ONSHORE FLOW IN THE LOW LEVELS OF THE ATMOSPHERE WILL
CONTINUE TO ADVECT SOME MOISTURE INLAND...BUT TO WHAT EXTENT IS
STILL UNCERTAIN. EITHER WAY DO NOT ANTICIPATE MUCH IN THE WAY OF
CLOUD COVER...WITH THE GREATEST COVERAGE ACROSS NORTH COASTAL
GEORGIA. THE ONSHORE FLOW AND MODERATING AIRMASS WILL NOT ALLOW
TEMPERATURES TO FALL AS SIGNIFICANTLY AS THE PAST COUPLE OF
MORNINGS...WITH LOW TEMPERATURES EXPECTED TO RANGE FROM THE LOWER
40S WELL INLAND TO THE UPPER 40S TOWARD THE COAST. AREAS ALONG THE
IMMEDIATE COAST WILL BE SIGNIFICANTLY WARMER.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
FAIRLY GOOD MODEL AGREEMENT INTO MONDAY LEADS TO HIGHER THAN
NORMAL FORECAST CONFIDENCE...THEN CONFIDENCE LOWERS A BIT THROUGH
MID WEEK DUE TO THE UNCERTAINTY WITH REGARD TO TROPICAL CYCLONE
IDA...OR ITS REMNANTS.
HIGH PRESSURE TO THE NORTH WILL CONTINUE THROUGH MONDAY BEFORE THE
THE HIGH BEGINS TO BREAK DOWN DUE TO THE APPROACH OF A SURFACE AREA
OF LOW PRESSURE FROM THE SOUTH AND AN UPPER LEVEL TROUGH FROM THE
WEST. A STRONG AREA OF HIGH PRESSURE BUILDING IN QUICKLY BEHIND THE
DEPARTING TROUGH TUE NIGHT SHOULD HELP KEEP THE LOW /TC IDA OR ITS
REMNANTS/ SOUTH AND EAST OF THE AREA. HOWEVER...AN INCREASE IN
TROPICAL MOISTURE OVER THE SOUTHEAST ALONG WITH THE APPROACHING
FRONT WILL YIELD INCREASING RAIN CHANCES FROM MONDAY NIGHT AND
TUESDAY. DRIER WEATHER IS THEN EXPECTED BEHIND THE COLD FRONT
WEDNESDAY AND THURSDAY. THE TREND IS FOR LOWER POPS WEDNESDAY SO
HAVE FOLLOWED SUITE BUT DID NOT PULL POPS COMPLETELY JUST YET.
ALSO...AS PWATS INCREASE TO AROUND 2 INCHES /WHICH IS ABOUT 2
STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF YEAR/ AND THE AREA
BECOMES SITUATED IN A FAVORABLE JET ENTRANCE REGION...THERE IS A
CHANCE FOR AT LEAST A FEW INCHES OF RAIN FROM THIS EVENT.
TEMPERATURES WILL GENERALLY BE NEAR NORMAL THROUGH THE PERIOD EXCEPT
FOR ABOVE NORMAL TEMPERATURES SUNDAY...MONDAY AND FRIDAY.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL AT KCHS AND KSAV THROUGH 06Z SUNDAY.
THE AIRMASS WILL REMAIN EXTREMELY DRY THROUGH THIS MORNING AT BOTH
TERMINALS...LEADING TO CLEAR SKIES. A LOW LEVEL ONSHORE FLOW COULD
ADVECT A FEW STRATOCUMULUS ONSHORE DURING THE AFTERNOON...AND
POSSIBLY THROUGH SATURDAY NIGHT AT KSAV...BUT NO CEILINGS ARE
ANTICIPATED AT THIS TIME. WINDS WILL REMAIN BELOW 10 KT THROUGH
THE FORECAST PERIOD.
EXTENDED AVIATION OUTLOOK...VFR CONDITIONS WILL PREVAIL THROUGH
MONDAY. THE COMBINATION OF A STORM SYSTEM LIFTING NORTHEAST OUT OF
THE GULF OF MEXICO AND A COLD FRONT APPROACHING FROM THE WEST WILL
RESULT IN UNSETTLED WEATHER AND THE POTENTIAL FOR MVFR OR IFR
CONDITIONS MONDAY NIGHT THROUGH WEDNESDAY. LLWS IS ALSO POSSIBLE
WEDNESDAY MORNING.
&&
.MARINE...
HIGH PRESSURE WILL SHIFT OFFSHORE NORTH OF THE AREA TODAY...CAUSING
NORTHEAST WINDS TO SHIFT EAST THIS AFTERNOON. THE SURFACE PRESSURE
GRADIENT WILL NOT BE TIGHT ENOUGH TO SUPPORT WINDS ANY GREATER
THAN 10-15 KT ACROSS THE WATERS THROUGH THIS AFTERNOON. SEAS WILL
GENERALLY RANGE FROM 2-3 FT ACROSS THE NEARSHORE WATERS AND 3-4 FT
ACROSS THE OUTER GEORGIA WATERS.
HIGH PRESSURE WILL LINGER OVER THE WESTERN ATLANTIC TONIGHT...KEEPING
AN ONSHORE FLOW IN PLACE WITH WIND SPEEDS 15 KT OR LESS AND SEAS 4
FT OR LESS.
SUNDAY THROUGH WEDNESDAY...HIGH PRES WILL REMAIN N OF THE AREA EARLY
NEXT WEEK AS AN AREA OF LOW PRES /POSSIBLY TS IDA/ TRACKS N/NE OUT
OF THE GULF OF MEX. MEANWHILE...A COLD FRONT WILL PUSH ACROSS THE
AREA TUE/TUE NIGHT WHICH WILL KEEP THE LOW S AND E OF THE AREA.
HOWEVER...A VERY STRONG PRES GRADIENT WILL SET UP B/W THE LOW AND A
BUILDING HIGH PRES SYSTEM INLAND. SMALL CRAFT ADVISORIES ARE
EXPECTED ACROSS ALL WATERS BY TUE AND GALES ARE EVEN POSSIBLE
WED/WED NIGHT...ESPECIALLY ACROSS THE WATERS BEYOND 20 NM.
&&
.TIDES/COASTAL FLOODING...
TIDAL DEPARTURES WILL REMAIN ELEVATED THIS MORNING DUE TO A
PERSISTENT NORTHEAST FLOW. THE POSSIBILITY OF COASTAL FLOODING
ALONG PARTS OF THE SOUTHERN SOUTH CAROLINA COAST WILL REMAIN IN
THE HAZARDOUS WEATHER OUTLOOK AS ANOTHER COASTAL FLOOD ADVISORY FOR
SHALLOW COASTAL FLOODING MAY BE NEEDED.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...FROST ADVISORY UNTIL 8 AM EST THIS MORNING FOR GAZ087-088-
099>101-114-115.
SC...FROST ADVISORY UNTIL 8 AM EST THIS MORNING FOR SCZ040-042>045-
047.
MARINE...NONE.
&&
$$
JAQ/RJB
000
FXUS62 KGSP 070748
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
248 AM EST SAT NOV 7 2009
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH MONDAY.
MOISTURE ASSOCIATED WITH TROPICAL STORM IDA IS EXPECTED TO MOVE INTO
THE CAROLINAS AND NORTH GEORGIA AHEAD OF A COLD FRONT TUESDAY...WITH
THE FRONT EXPECTED TO CROSS THE AREA ON TUESDAY NIGHT AND EARLY
WEDNESDAY. HIGH PRESSURE WILL THEN RETURN FOR THE LATER HALF OF NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPPER RIDGE AXIS CONTINUES TO BUILD OVERHEAD WITH THIN HIGH CLOUDS
AND CALM TO LGT S WINDS THIS MRNG. AFTER A COLD START...SEE FREEZE
WARNING/FROST ADVISORY FOR PIEDMONT AREAS...TEMPS WILL WARM QUICKLY
TODAY. HIGHS SHOULD REACH INTO THE M-U60S ACROSS THE PIEDMONT WITH
L-M60S MTNS. UPPER RIDGE CONTINUES TO BUILD TONIGHT WITH S-SW WINDS
AT THE SFC. EVEN THOUGH SKIES WILL BE MCLEAR OVERNIGHT...RISING
THICKNESS WILL KEEP TEMPS IN THE U30S-L40S ACROSS THE PIEDMONT WITH
30S IN THE MTNS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 225 AM SATURDAY...THE UPPER RIDGE WILL CONTINUE BUILD ALONG
THE EAST COAST THROUGH SUNDAY NIGHT...BEFORE BEGINNING A SLIGHT
EASTWARD PROGRESSION/BREAK DOWN BY THE END OF THE SHORT TERM. HIGH
MID-LEVEL HEIGHTS/INCREASED THICKNESS WILL RESULT IN VERY WARM MAXES
THROUGH THE PERIOD...WITH MANY AREAS OF THE PIEDMONT EXPECTED TO
REACH THE MID 70S SUNDAY AFTERNOON. EVEN THE MTN VALLEYS COULD SEE
THE LOWER 70S. MUCH OF THE SAME IS EXPECTED ON MONDAY...ALTHOUGH
INCREASING HIGH CLOUDS MAY MODERATE TEMPS JUST A BIT. ALTHOUGH GOOD
RADIATIONAL COOLING CONDITIONS SHOULD ALLOW LOWS TO SETTLE TO NEAR
NORMAL LEVELS...FROST/FREEZE WILL NOT BE A CONCERN DURING THIS
TIME.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 230 AM SATURDAY...WEATHER BECOMES MORE ACTIVE DURING THE EARLY
PART OF THE MEDIUM RANGE...AS A SW TROUGH DIGGING ACROSS THE UPPER
MIDWEST RESULTS IN COMPLETE BREAKDOWN/EASTWARD PROGRESSION OF THE
UPPER RIDGE. MEANWHILE...TROPICAL STORM IDA IS EXPECTED TO BE MOVING
NORTHEAST ACROSS THE CENTRAL/NORTHERN GULF EARLY TUESDAY. THE GFS
AND ECMWF ARE IN VERY GOOD AGREEMENT IN SPREADING MOISTURE
ASSOCIATED WITH IDA INTO THE CAROLINAS TUESDAY...BEFORE THE UPPER
TROUGH AND ASSOCIATED COLD FRONT SWEEP IT OFF THE SOUTHEAST COAST
EARLY WEDNESDAY. THE NAM IS NOT AS EXCITED ABOUT THIS SCENARIO.
CONSIDERING ITS TRACK RECORD AND SUPPORT FROM OTHER MODELS...IT
APPEARS THE GFS IS THE WAY TO GO WITH THIS FORECAST. HOWEVER...THERE
IS STILL SUFFICIENT UNCERTAINTY TO CONTINUE WITH A CONSERVATIVE POP
FORECAST. WE WILL MAINTAIN AN AREA OF LIKELY POPS ACROSS THE SOUTH
TUESDAY...BUT HAVE ACTUALLY TEMPERED POPS A BIT ACROSS THE NORTH.
AFTER LINGERING TOKEN CHANCE POPS ACROSS THE AREA TUE NIGHT...THE
REMAINDER OF THE EXTENDED PERIODS APPEAR TO BE DOMINATED BY DRY/COOL
HIGH PRESSURE.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
AT KCLT AND ELSEWHERE...SKC TO SCT250 WITH LGT S TO SW WIND...
INCRSNG TO 5-10 KTS THRU THE AFTN.
OUTLOOK...VFR WITH HIGH PRESSURE INTO THE FIRST PART OF NEXT WEEK.
EXPECTED AREAS OF MRNG FOG...MAINLY NEAR RIVERS AND LAKES. COLD
FRONT MOVES IN TUE WITH CHC SHWRS AND CIG/VSBY RESTRICTIONS.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FROST ADVISORY UNTIL 9 AM EST THIS MORNING FOR GAZ018-026-028.
FREEZE WARNING UNTIL 9 AM EST THIS MORNING FOR GAZ029.
NC...FROST ADVISORY UNTIL 9 AM EST THIS MORNING FOR NCZ508-510.
FREEZE WARNING UNTIL 9 AM EST THIS MORNING FOR NCZ035>037-056-
057-068>072-082.
SC...FROST ADVISORY UNTIL 9 AM EST THIS MORNING FOR SCZ001>007-010.
FREEZE WARNING UNTIL 9 AM EST THIS MORNING FOR SCZ008-009-
011>014-019.
&&
$$
SYNOPSIS...JDL
NEAR TERM...RB
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...RB
000
FXUS62 KCHS 070535
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1235 AM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE
WEEKEND. THE COMBINATION OF A STORM SYSTEM LIFTING OUT OF THE GULF
OF MEXICO AND A COLD FRONT APPROACHING FROM THE WEST WILL KEEP
THINGS UNSETTLED DURING THE EARLY TO MIDDLE PART OF NEXT WEEK.
HIGH PRESSURE WILL THEN BUILD BACK INTO THE REGION FOR THURSDAY
AND FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
A COLD AND DRY HIGH PRESSURE WILL REMAIN ACROSS THE AREA
TONIGHT...RESULTING IN CLEAR SKIES AND MOSTLY CALM WINDS.
EXCELLENT RADIATIONAL COOLING WILL BE THE END RESULT...WITH THE
COLDEST AIR OF THE SEASON FOR MANY LOCATIONS. WE LOOK FOR AN
AVERAGE TEMP FALL OF ABOUT A DEGREE AN HOUR THROUGH THE
NIGHT...WHICH WILL PRODUCE LOWEST TEMPS DOWN INTO THE MID AND
UPPER 30S JUST ABOUT EVERYWHERE NEAR AND WEST OF US-17. WHILE WE
HAVE EXPANDED THE COVERAGE OF PATCHY FROST A LITTLE FURTHER EAST
INTO CHARLESTON COUNTY AND ALSO INTO FAR NORTHERN BEAUFORT
COUNTY...THERE IS NO CHANGE TO THE COUNTIES IMPACTED BY OUR FROST
ADVISORY. THE GREATEST COVERAGE OF FROST WILL BE ROUGHLY NW OF A
LINE FROM SHULERVILLE TO SUMMERVILLE TO JACKSONBORO AND RIDGELAND
IN SC...AND NW OF A LINE FROM RINCON TO CLAXTON AND REIDSVILLE IN
GA. THE EXCEPTION WILL BE THE URBAN COMMUNITIES AND LOCATIONS NEAR
LARGE BODIES OF WATER...WHERE WARMER TEMPS WILL OCCUR.
NEAR AND ALONG THE COAST A N-NE BREEZE OF 5-10 MPH WILL CONTINUE
THROUGH THE NIGHT. THIS WILL KEEP TEMPS AT LEAST 15-20 DEGREES
HIGHER THAN INLAND...WITH MODERATING INFLUENCES FROM THE ATLANTIC.
LOOK FOR LOWEST READINGS AROUND 50 IN MANY AREAS EAST OF THE
INTRACOASTAL...BUT EVEN SOME LOWER TO MID 50S IN PLACES SUCH AS
FOLLY BEACH AND TYBEE ISLAND.
THERE WAS A LARGE PRESCRIBED BURN NEAR SHULERVILLE AGAIN EARLIER
TODAY...WHICH SHOWED UP NICELY ON IR 3.9 MICRON SATELLITE
IMAGES...AND WAS ALSO VISIBLE IN THE DISTANT NE HORIZON FROM THE
LOCAL AREA. WE HAVE NOT YET HEARD FROM ANY FIRE WEATHER OFFICIALS
NEAR THAT SITE TO SEE IF ANY LINGERING SMOKE IS STILL
OCCURRING...AS THE BURN HAS LONG SINCE ENDED HAVING LAST SHOWN ON
SATELLITE AT 2015Z FRIDAY.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
HIGH PRESSURE WILL SHIFT OFF THE NORTH CAROLINA COAST INTO THE
WESTERN ATLANTIC SATURDAY...ALLOWING FOR THE WINDS TO SHIFT
ONSHORE AND THE AIR MASS TO MODERATE. COULD SEE A FEW FAIR
WEATHER CUMULUS DEVELOP...BUT OVERALL SUNNY SKIES ARE ANTICIPATED.
LOW LEVEL THICKNESS VALUES SUPPORT HIGHS GENERALLY IN THE LOWER
70S...AND SEE NO REASON TO DEVIATE FROM THESE VALUES.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
MEDIUM RANGE GUIDANCE IS IN EXCELLENT AGREEMENT THROUGH THE
WEEKEND...WITH SOLUTIONS THEN DIVERGING BY THE EARLY TO MIDDLE PART
OF THE UPCOMING WORK WEEK.
SATURDAY NIGHT THROUGH MONDAY...
HIGH PRESSURE OVER THE WESTERN ATLANTIC WILL REMAIN THE DOMINANT
WEATHER FEATURE OVER THE FORECAST AREA SATURDAY THROUGH SUNDAY
NIGHT...RESULTING IN RAIN FREE WEATHER. BY MONDAY...BOUNDARY LAYER
MOISTURE WILL CONTINUE TO SLOWLY INCREASE DUE TO THE PERSISTENT
EASTERLY FLOW OFF THE ATLANTIC...AND ALTHOUGH AN ISOLATED SHOWER
CAN/T BE RULED OUT...PROBABILITIES FOR ANY MEASURABLE RAINFALL
APPEAR TOO LOW TO INCLUDE IN THE FORECAST AT THIS TIME.
THEREFORE...WILL KEEP THE FORECAST RAIN FREE ON MONDAY.
MONDAY NIGHT THROUGH WEDNESDAY NIGHT...
THE FORECAST BECOMES A BIT MORE INTERESTING MONDAY NIGHT THROUGH
WEDNESDAY NIGHT...WITH GUIDANCE SOLUTIONS OFFERING UP A NUMBER OF
POSSIBILITIES WITH RESPECT TO A STORM SYSTEM LIFTING NORTHWARD OUT
OF THE GULF OF MEXICO. ALTHOUGH EXACT TIMING AND TRACK DETAILS LEAVE
QUITE A BIT TO BE DESIRED...GUIDANCE DOES AGREE FAIRLY WELL THAT
DEEP MOISTURE AND ISENTROPIC ASCENT WILL BEGIN TO OVERSPREAD THE
REGION MONDAY NIGHT AND CONTINUE TO IMPACT THE AREA THROUGH TUESDAY
NIGHT BEFORE A STRONG UPPER LEVEL TROUGH APPROACHING FROM THE WEST
PUSHES THE STORM SYSTEM EASTWARD AND INTO THE ATLANTIC. THE GFS
ISN/T AS STRONG AS THE OPERATIONAL MODELS WITH THE APPROACHING UPPER
LEVEL TROUGH...AND STALLS THE STORM SYSTEM OFFSHORE THROUGH LATE
IN THE WEEK. FOR NOW...WILL FOLLOW GUIDANCE CONSENSUS WHICH
MAINTAINS GOOD PERSISTENCE...AND FORECAST THE SYSTEM TO SHIFT
OFFSHORE WEDNESDAY WITH HIGH PRESSURE THEN BUILDING BACK INTO THE
REGION WEDNESDAY NIGHT. AS FOR FORECAST DETAILS...WILL INCREASE
POPS IN THE MONDAY NIGHT THROUGH WEDNESDAY TIME FRAME AS A DECENT
RAIN EVENT IS APPEARING MORE LIKELY...WITH RAIN FREE WEATHER TO
FOLLOW WEDNESDAY NIGHT.
THURSDAY THROUGH FRIDAY...
THE FAVORED ECMWF/CANADIAN SOLUTIONS SHOW THE SYSTEM PUSHING FURTHER
EASTWARD INTO THE ATLANTIC THURSDAY...WITH HIGH PRESSURE BUILDING
BACK INTO THE REGION THROUGH FRIDAY. WILL KEEP THE FORECAST RAIN
FREE THROUGH THIS PERIOD.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PREVAIL AT KCHS AND KSAV THROUGH 06Z SUNDAY.
THE AIRMASS WILL REMAIN EXTREMELY DRY THROUGH THIS MORNING AT BOTH
TERMINALS...LEADING TO CLEAR SKIES. A LOW LEVEL ONSHORE FLOW COULD
ADVECT A FEW STRATOCUMULUS ONSHORE DURING THE AFTERNOON...AND
POSSIBLY THROUGH SATURDAY NIGHT AT KSAV...BUT NO CEILINGS ARE
ANTICIPATED AT THIS TIME. WINDS WILL REMAIN BELOW 10 KT THROUGH
THE FORECAST PERIOD.
EXTENDED AVIATION OUTLOOK...VFR CONDITIONS WILL PREVAIL THROUGH
MONDAY. THE COMBINATION OF A STORM SYSTEM LIFTING NORTHEASTWARD
OUT OF THE GULF OF MEXICO AND A COLD FRONT APPROACHING FROM THE
WEST...WILL RESULT IN UNSETTLED WEATHER AND THE POTENTIAL FOR MVFR
OR IFR CONDITIONS MONDAY NIGHT THROUGH WEDNESDAY.
&&
.MARINE...
TONIGHT...HIGH PRESSURE WILL REMAIN CENTERED OVER THE MID ATLANTIC
STATES OVERNIGHT...WITH ITS ASSOCIATED RIDGE AXIS STRETCHING SW
TO THE GULF COAST. THIS WILL KEEP SUBTLE PINCHING OF THE PRESSURE
GRADIENT ACROSS THE COASTAL WATERS...AS NE WINDS REMAIN AS HIGH AS
AROUND 15 KT. THIS FAVORABLE FETCH WILL ALSO ALLOW FOR SEAS TO
CHANGE LITTLE THROUGH THE NIGHT...AT 5 FT OR LESS. AS A RESULT WE
HAVE DROPPED THE SCA FOR AMZ374...AS THE HIGHEST REPORT OF SEAS WE
CAN FIND ANYWHERE NEAR THE MARINE AREA WOULD BE THE 5 FOOTERS AT
BUOY 41012 OFF THE NE FLORIDA COAST.
SATURDAY THROUGH WEDNESDAY...HIGH PRESSURE WILL REMAIN THE
DOMINANT WEATHER FEATURE OVER THE WEEKEND. A STORM SYSTEM WILL
THEN MOVE TRACK ACROSS THE REGION DURING THE EARLY TO MIDDLE PART
OF NEXT WEEK. FAIRLY TRANQUIL CONDITIONS ARE EXPECTED SATURDAY
NIGHT AND SUNDAY WITH WINDS AND SEAS REMAINING BELOW SMALL CRAFT
THRESHOLDS. EXPECT THE GRADIENT TO GRADUALLY TIGHTEN UP SUNDAY
NIGHT THROUGH WEDNESDAY AS A STORM SYSTEM LIFTS NORTHEASTWARD OUT
OF THE GULF OF MEXICO AND A STRONG RIDGE OF HIGH PRESSURE BUILDS
NORTH OF THE REGION. THIS WILL RESULT IN A LONG DURATION OF
NORTHEASTERLY FLOW OVER THE WATERS...AND SEAS MAY BUILD TO SMALL
CRAFT LEVELS AS EARLY AS SUNDAY NIGHT ACROSS THE OUTER GEORGIA
WATERS. SMALL CRAFT CONDITIONS MAY IMPACT THE NEARSHORE WATERS
MONDAY THROUGH WEDNESDAY AS THE GRADIENT TIGHTENS AND SEAS
CONTINUE TO BUILD.
&&
.TIDES/COASTAL FLOODING...
TIDAL DEPARTURES WILL REMAIN ELEVATED SATURDAY MORNING DUE TO A
PERSISTENT NORTHEAST FLOW...AND THE POSSIBILITY OF COASTAL
FLOODING WILL REMAIN IN THE HAZARDOUS WEATHER OUTLOOK AS WE MAY
NEED TO ISSUE ANOTHER COASTAL FLOOD ADVISORY FOR SHALLOW COASTAL
FLOODING.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...FROST ADVISORY UNTIL 8 AM EST THIS MORNING FOR GAZ087-088-
099>101-114-115.
SC...FROST ADVISORY UNTIL 8 AM EST THIS MORNING FOR SCZ040-042>045-
047.
MARINE...NONE.
&&
$$
000
FXUS62 KCAE 070520
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1220 AM EST SAT NOV 7 2009
.SYNOPSIS...
HIGH PRESSURE WILL DOMINATE THE WEATHER THROUGH THE WEEKEND. THE
NEXT FRONT WILL APPROACH THE AREA TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
REMAINDER OF TONIGHT...CLEAR SKIES AND CALM WINDS WILL REMAIN.
CURRENT OBS FOR BOTH TEMPS AND DEWPOINTS RUNNING BELOW GUIDANCE AT
THIS TIME. HAVE TWEAKED GRIDS FOR CURRENT OBS AND TRENDS. FROST
ADVISORY LOOKS GOOD FOR THE MORNING HOURS AS MOST AREAS WILL BE AT
OR SLIGHTLY ABOVE FREEZING BY SUNRISE. HELD OFF ON UPGRADING TO A
FREEZE WARNING DUE TO THE FACT THAT IF TEMPS DO FALL TO JUST BELOW
FREEZING...THEY WILL BE THERE ONLY BRIEFLY AND QUICKLY REBOUND
ONCE THE SUN RISES.
PREVIOUS DISCUSSION...LARGE AREA OF DRY HIGH PRESSURE DOMINATES
MUCH OF THE MID-ATLANTIC AND THE SOUTHEAST. AS THE CENTER OF THE
HIGH PRESSURE MOVES OVER THE CAROLINAS AND WITH EXCELLENT
RADIATIONAL COOLING ANTICIPATED...EXPECT FORECAST MIN TEMPS TO DIP
INTO THE MID 30S OVER MUCH OF THE FA BY SUNRISE SATURDAY MORNING.
A FEW AREAS COULD BRIEFLY TOUCH THE FREEZING MARK. WILL CONTINUE
WITH FROST ADVISORY FOR THE AREA EARLY SATURDAY MORNING.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH SUNDAY NIGHT/...
TEMPS WILL MODERATE THROUGH THE SHORT TERM AS THE CENTER OF HIGH
PRESSURE MOVES OFF THE ATLANTIC COAST. DAYTIME TEMPS WILL RISE
INTO THE LOW TO MID 70S SATURDAY AND SUNDAY WITH OVERNIGHT LOWS IN
THE UPPER 30S SATURDAY NIGHT TO THE LOWER 40S SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
LOW CONFIDENCE AS TO THE DEVELOPMENT OF THE FORECAST PATTERN BY
MIDWEEK. GFS SHOWS HIGH PRESSURE MOVING FARTHER OFFSHORE AS
TROPICAL CYCLONE IDA MOVES NORTHWARD FROM THE CARIBBEAN SEA INTO
THE NORTHERN GULF OF MEXICO. A COLD FRONT WILL APPROACH FROM THE
NORTHWEST TUESDAY INTO EARLY WEDNESDAY. THE LATEST GFS NOW SHOWS
THAT SOME COLD AIR DAMMING MAY OCCUR OVER THE SE STATES LATE
WEDNESDAY INTO THURSDAY AS AN AREA OF LOW PRESSURE...POSSIBLY
ASSOCIATE WITH IDA...CROSSING THE FL PENINSULA MOVING OFF THE
CAROLINA COAST BY THURSDAY. THIS SCENARIO COULD BRING SOME
POSSIBLE GUSTY WINDS TO THE FA WITH THE HELP OF A STRONG PRESSURE
GRADIENT. FOR NOW...WILL CONTINUE MENTION OF CHANCE POPS MAINLY
TUESDAY INTO EARLY WEDNESDAY. DRY WEATHER LATE WEEK AS HIGH
PRESSURE BUILDS IN FROM THE NORTH. TEMPS CLOSE TO MEX NUMBERS.
&&
.AVIATION /05Z SATURDAY THROUGH WEDNESDAY/...
DRY HIGH PRESSURE WILL REMAIN IN PLACE THROUGH THE TAF PERIOD. VFR
CONDITIONS SHOULD CONTINUE.
EXTENDED AVIATION OUTLOOK...WIDESPREAD CEILING AND VISIBILITY
RESTRICTIONS MAY OCCUR TUESDAY INTO WEDNESDAY ASSOCIATED WITH
ISENTROPIC LIFT.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...FROST ADVISORY UNTIL 7 AM EST THIS MORNING FOR SCZ015-016-018-
020>022-025>031-035>038-041.
GA...FROST ADVISORY UNTIL 7 AM EST THIS MORNING FOR GAZ040-063>065-
077.
&&
$$
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