[top]
000
FXUS66 KPQR 230449
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
848 PM PST SUN NOV 22 2009
.SYNOPSIS...ISOLATED SHOWERS WILL CONTINUE TO DECREASE TONIGHT AS
A WEAK UPPER RIDGE SHIFTS INTO OREGON. A WEAK WARM FRONT OFF THE
COAST WILL SHIFT NORTHEAST ON MONDAY...THEN STALL OVER THE REGION ON
TUESDAY. THE FRONT WILL FINALLY LIFT NORTH INTO WASHINGTON ON
WEDNESDAY...BEFORE A COLD FRONT PUSHES SOUTHEAST INTO THE REGION LATE
THURSDAY.
&&
.SHORT TERM...SATELLITE IMAGERY AND METARS SHOW THE CLOUDS BREAKING
UP OVER THE VALLEYS THIS EVENING...WHILE WEAKENING ONSHORE FLOW IS
STILL ALLOWING SOME SHOWERS OVER THE MOUNTAINS. HOWEVER SATELLITE AND
MODELS SUGGEST MID LEVEL CLOUDS AHEAD OF A WEAK WARM FRONT WILL
ADVECT INTO THE REGION OVERNIGHT...BUT MODELS SHOWING NO QPF EXCEPT
FOR A LITTLE RESIDUAL PRECIP OVER THE NORTHERN MOUNTAINS...AS WEAK
SUBSIDENCE DEVELOPS AS A PRECURSOR UPPER RIDGE SHIFTS INLAND. ADDED
SOME PATCHY VALLEY FOG FOR EARLY MON BUT THIS MIGHT NOT MATERIALIZE
IF THE MID LEVEL CLOUDS ARE THICK ENOUGH. RW
REMAINDER OF SHORT TERM UNCHANGED...
AN AREA OF WARM AIR ADVECTION SETS UP OVER THE NW PART OF THE
FORECAST AREA MON...AND CONTINUES INTO TUE. A WEAK SHORTWAVE MOVES
ACROSS THE TOP OF THE DEVELOPING UPPER RIDGE TUE...BRINGING THE BEST
CHANCE FOR OVERRUNNING PRECIPITATION TO THE NW PART OF THE AREA ON
MON NIGHT WITH THE SHORT WAVE MOVING THROUGH THE FORECAST AREA
WEDNESDAY.
.LONG TERM...MODELS IN SOME AGREEMENT ON BRINGING A FRONTAL SYSTEM
AND ITS ASSOCIATED UPPER LEVEL TROF THROUGH THE REGION THU/THU NIGHT
FOR A RETURN TO WET WEATHER. AFTER THIS SYSTEM MOVES THROUGH...THE
WEAK HIGH PRES RIDGE REASSERTS ITSELF OVER THE FORECAST
AREA...KEEPING MOST ENERGY NORTH OF FORECAST AREA.
&&
.AVIATION...CLOUDS AND SHOWERS CONTINUE TO DECREASE THIS EVENING AS
HIGH PRESSURE BUILDS OVERHEAD. DESPITE RELATIVELY STRONG GRADIENTS
THIS EVENING WINDS ACROSS MOST AREAS ARE CALM. WITH RECENT RAINS AND
CLEARING SKIES AREAS OF IFR FOG MAY FORM IN FAVORED AREAS SUCH AS
HILLSBORO AND THE SOUTH WILLAMETTE VALLEY AFTER 09Z...OTHERWISE
EXPECT VFR CONDITIONS. THE NEXT SYSTEM WILL BEGIN TO MOVE IN MONDAY
AFTERNOON WITH RAIN STARTING IN THE AFTERNOON ON THE COAST.
KPDX AND APPROACHES...VFR CONDITIONS EXPECTED TONIGHT. HOWEVER...
THERE IS A 30% CHANCE OF IFR FOG OR STRATUS BETWEEN 10Z AND 18Z.
&&
.MARINE...LIGHT WINDS WILL CONTINUE TONIGHT. WINDS WILL INCREASE TO
GALE FORCE BY LATE MONDAY MORNING ACROSS THE NORTHERN WATERS AND
SMALL CRAFT ACROSS THE SOUTHERN WATERS. SEAS AT 15-18 FT THIS EVENING
WILL DROP TONIGHT TO NEAR 11 FT BEFORE BUILDING BACK INTO THE MID
TEENS ON MONDAY EVENING.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
WA/OR...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CAPE SHOALWATER TO
FLORENCE THROUGH MONDAY MORNING.
SMALL CRAFT ADVISORY FOR WINDS CAPE SHOALWATER TO
CASCADE HEAD MONDAY MORNING.
SMALL CRAFT ADVISORY FOR WINDS CASCADE HEAD TO FLORENCE
MONDAY AND MONDAY EVENING.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR CONDITIONS
THROUGH MON NIGHT.
GALE WARNING FROM CAPE SHOALWATER TO CASCADE HEAD MONDAY
THROUGH EARLY MONDAY EVENING.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
[top]
000
FXUS66 KMFR 230446
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
850 PM PST SUN NOV 22 2009
.DISCUSSION...HIGH PRESSURE ALOFT IS BUILDING BRINGING INCREASING
STABILITY OVER THE REGION. ALL SHOWERS HAVE ENDING IN OUR REGION.
LIGHT WINDS...LONG NIGHTS...SURFACE HIGH PRESSURE AND RECENT RAIN
AND SNOWFALL IS A PERFECT SCENARIO FOR FOG DEVELOPING IN THE VALLEYS
IN THE WEST AND EAST SIDE. MONDAY THROUGH WEDNESDAY WILL FEATURE FOG
FORMING AFTER MIDNIGHT IN FAVORED VALLEYS. THE FOG WILL LIFT TO LOW
CLOUDS AND EVENTUALLY CLEAR AROUND NOON IN MOST LOCATIONS. TUESDAY A
WEAK COLD FRONT BRUSHES THE COASTAL ZONES...BUT RAIN CHANCES ARE
VERY LOW. CLEARING TIME WILL DICTATE HOW WARM TEMPERATURES GET
DURING THE FIRST HALF OF THE WEEK. CURRENT FORECAST PRESENTS THE
IDEA THAT WEDNESDAY WILL BE THE WARMEST DAY AS GFS AND NAM AGREE
THAT AIRMASS MAY BE 1-2 STANDARD DEVIATIONS ABOVE AVERAGE BY THAT
TIME. CLOUDS WILL BE MOSTLY OF THE MID AND HIGH VARIETY THIS WEEK.
WEATHER FOR THANKSGIVING DAY TRAVEL IS GRADUALLY COMING INTO
FOCUS. GFS ENSEMBLE MEMBERS ALL INDICATE A SIMILAR IDEA OF AN
UPPER TROUGH AND COLD FRONT AFFECTING NORTHERN CALIFORNIA AND
OREGON BY THURSDAY AFTERNOON. SNOW LEVELS WILL INITIALLY BE
BETWEEN 5000 TO 7000 FEET BUT WILL FALL THURSDAY NIGHT AND END UP
AROUND 3500 FEET FRIDAY MORNING. THE ECMWF INDICATES MORE MOISTURE
THAN THE GFS SO WILL NEED TO MONITOR TRENDS IN THE NEAR-TERM.
SISKIYOU PASS WILL NOT LIKELY HAVE SIGNIFICANT SNOW IMPACTS WITH
THIS WEATHER SYSTEM. HOWEVER...AS COLD AIR FOLLOWS THE COLD
FRONT...SOME SNOW MAY ACCUMULATE AT PASS LEVEL LATE THURSDAY NIGHT
OR EARLY FRIDAY MORNING.
&&
.AVIATION...VFR CONDITIONS ARE EXPECTED TO CONTINUE AT ALL TAF
SITES THROUGH LATE TONIGHT WHEN FOG FORMS AT RBG AND
MFR...RESULTING IN IFR CONDITIONS THAT SHOULD LAST THROUGH MIDDAY
MONDAY. MOUNTAIN OBSCURATION WILL CONTINUE TO IMPACT MOST OF THE
HIGH TERRAIN THROUGH ABOUT 06Z WHEN DRY AIR BEGINS TO FILTER INTO
THE ELEVATED AREAS AND CLOUDS THERE DIMINISH.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...HAZARDOUS SEAS WARNING UNTIL 4 AM PST
MONDAY FOR PZZ350-PZZ356-PZZ370-PZZ376.
$$
11
[top]
000
FXUS66 KPDT 230430
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
830 PM PST SUN NOV 22 2009
.UPDATE...UPPER LEVEL LOW HAS MOVED INTO WESTERN MONTANA THIS
EVENING AND ACTIVE WEATHER HAS BEEN STEADILY WINDING DOWN. RADAR
STILL SHOWS A FEW LIGHT SNOW SHOWERS IN THE EASTERN MOUNTAINS BUT
INTENSITY IS MUCH REDUCED IN THE LAST FEW HOURS. HAVE ALREADY
ALLOWED WINTER STORM WARNING FOR THE NORTHERN BLUE MOUNTAINS TO
EXPIRE ON SCHEDULE. PRESSURE GRADIENTS HAVE RELAXED CONSIDERABLY IN
THE LAST SEVERAL HOURS AND WINDS HAVE ALSO BEEN DYING DOWN. HAVE
ALLOWED WIND ADVISORY FOR THE BLUE MOUNTAIN FOOTHILLS OF OREGON TO
EXPIRE EARLIER THIS EVENING. WINDS ARE GENERALLY IN THE 10 TO 20 MPH
RANGE WITH A FEW GUSTS TO 25 OR 30 MPH. HAVE UPDATED WINDS THE REST
OF THE NIGHT TO REFLECT THE WINDS DROPPING OFF FASTER THAN FORECAST.
HAVE ALSO MADE A FEW ADJUSTMENTS TO POPS. TEMPERATURES LOOK GOOD.
UPDATE OUT SHORTLY. PERRY
&&
.PREV DISCUSSION... /ISSUED 302 PM PST SUN NOV 22 2009/
SHORT TERM...TONIGHT THROUGH TUESDAY...UPPER LEVEL LOW CENTER OVER
NORTHEAST WASHINGTON AT THIS HOUR WITH SURFACE LOW TRAILING SLIGHTLY
BEHIND ACROSS NORTH CENTRAL WASHINGTON. HAVE SEEN WIDESPREAD
ADVISORY WINDS TODAY WITH LOCALLY STRONGER GUSTS NEARING 60 MPH
NOTED JUST TODAY. OTHER STRONG WINDS HAVE BEEN REPORTED ALONG WITH
SOME DOWNED TREES AS WELL. REFER TO LOCAL STORM REPORTS FOR FURTHER
DETAILS. MANY WIND ADVISORIES AND WINTER WEATHER ADVISORIES WILL BE
ALLOWED TO EXPIRE AT 4 PM AS PLANNED WITH THE WIND ADVISORIES ALONG
THE FOOTHILLS AND THE WINTER WEATHER STATEMENTS FOR THE BLUE
MOUNTAINS LIKELY TO CONTINUE THROUGH THEIR PLANNED EXPIRATION OF 7
PM TONIGHT. SINCE THE PAIR OF LOW CIRCULATIONS HAVE PROGRESSED
SLIGHTLY FURTHER NORTH THAN EXPECTED, SNOW AMOUNTS OVER THE BLUE
MOUNTAINS HAVE BEEN ON THE LIGHT SIDE, BUT ACCUMULATION RATES HAVE
PICKED UP OVER THE LAST FEW HOURS, THUS WILL WAIT AND SEE.
WINDS AND PRECIPITATION WILL CONTINUE TO DECREASE ACROSS THE REGION
AS THE SYSTEM MOVES FURTHER EAST. EXPECT SOME LIGHT SNOW SHOWERS
WILL CONTINUE OVERNIGHT NEAR THE CASCADE CREST AND OVER THE
NORTHEASTERN MOUNTAINS BUT ACCUMULATIONS SHOULD BE FAIRLY LIGHT.
MONDAY WILL BE A RELATIVELY CALM DAY AS FLAT HIGH PRESSURE
CROSSES OVER THE REGION. THE SOUTHERN EDGE OF A COLD FRONT WILL CLIP
THE NORTHEASTERN THIRD OF THE CWA MONDAY NIGHT AND TUESDAY POSSIBLY
BRINGING ANOTHER COUPLE INCHES OF SNOW TO THE WASHINGTON CASCADE
EAST SLOPES AND NORTHEASTERN MOUNTAINS. THAT REALLY SEEMS TO BE THE
ONLY IMPACT THOUGH. IT APPEARS MOST OF THE REGION IS UNDER THE
CASCADE SHADOW INFLUENCE AND WILL REMAIN DRY. TEMPERATURES WILL
GENERALLY REMAIN ON THE COOLER SIDE AS WELL. /JBONK
LONG TERM...TUESDAY NIGHT THROUGH SUNDAY...AN UPPER RIDGE WILL
BUILD OVER EASTERN WASHINGTON AND OREGON TUESDAY NIGHT. SUBSIDENCE
FROM THE RIDGE WILL WILL PROVIDE CLEARING SKIES AND LIGHT WINDS
WITH STRONG SURFACE INVERSIONS TUESDAY NIGHT. IN THE LOWER COLUMBIA
BASIN PATCHY FOG AND FREEZING FOG WILL FORM AT NIGHT UNDER THE
INVERSIONS AND KEEP DAYTIME TEMPERATURES WEDNESDAY BELOW NORMAL. THE
FOG WILL FORM MAINLY ALONG THE LARGE RIVERS AND STREAMS AND THEN
GRADUALLY EXPAND IN COVERAGE WEDNESDAY NIGHT AND THURSDAY. AT HIGHER
ELEVATIONS THE SURFACE INVERSIONS WILL BREAK DURING THE DAY AND
WARMER AIR ALOFT ASSOCIATED WITH THE RIDGE WILL REACH THE SURFACE TO
PRODUCE LARGE DIURNAL TEMPERATURE SPREADS. A COLD FRONT WILL MOVE
INLAND THURSDAY AFTERNOON AND BRING ANOTHER ROUND OF PRECIPITATION
TO THE FORECAST AREA THURSDAY NIGHT AND FRIDAY. MORE SYSTEMS WILL
MOVE THROUGH SATURDAY AND SUNDAY. COONFIELD
AVIATION...0Z TAFS...VFR CONDITIONS WILL PREVAIL AT ALL LOCATIONS.
STRONG SOUTHWEST TO WEST 12 TO 25 KTS WILL DIMINISH OVERNIGHT. 76
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 32 46 37 41 / 10 10 20 10
ALW 34 47 36 42 / 10 10 20 10
PSC 29 45 35 45 / 10 10 10 10
YKM 24 42 31 49 / 10 10 20 10
HRI 28 45 32 45 / 10 10 10 10
ELN 27 40 27 40 / 10 10 30 10
RDM 20 46 25 47 / 10 10 10 10
LGD 25 40 30 42 / 20 10 20 20
GCD 21 44 25 52 / 10 10 10 10
DLS 33 45 35 49 / 20 10 40 20
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
MONDAY : GREEN
TUESDAY : GREEN
WEDNESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
83/76/76
[top]
000
FXUS65 KBOI 230347
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
847 PM MST SUN NOV 22 2009
.DISCUSSION...SNOW SHOWER ACTIVITY WAS DIMINISHING OVER THE
BOISE/WEST CENTRAL MOUNTAINS BUT FLURRIES WERE STILL OCCURRING PER
WEBCAMS. THIS TREND WILL CONTINUE WITH SCATTERED MTN SNOW SHOWERS
BECOMING ISOLATED OVERNIGHT AS THE UPPER TROUGH RESPONSIBLE FOR THE
ACTIVITY MOVES EAST. SKIES HAVE BEGUN CLEARING IN MANY AREAS OUTSIDE
OF THE BOISE/WEST CENTRAL MOUNTAINS. WINDS REMAIN GUSTY WITH SOME
GUSTS TOPPING 20 MPH BUT THOSE TOO WERE DIMINISHING. AREAS OF
CLEARING COINCIDING WITH LIGHT WINDS OVERNIGHT WILL BE LOCATIONS
PRONE TO FOG. WILL UPDATE FOR LOWER POPS AND LESS CLOUDS FOR THE
REMAINDER OF TONIGHT....OTHERWISE FORECAST IS IN GOOD SHAPE.
&&
.AVIATION...ISOLATED IFR CONDITIONS IN THE MOUNTAINS TONIGHT DUE TO
LOW CEILINGS...OTHERWISE VFR TONIGHT AND MONDAY. SURFACE WINDS
GENERALLY 10 KTS OR LESS TONIGHT WITH WINDS ALOFT MODERATE FROM THE
NORTHWEST. AS CLOUDS DECREASE TONIGHT AND WINDS BECOME
LIGHT...ESPECIALLY IN SHELTERED VALLEYS...CAN NOT RULE OUT AREAS OF
VALLEY FOG BY MONDAY MORNING. CAN EXPECT LOCAL MVFR CONDITIONS AND
ISOLATED IFR CONDITIONS IN VALLEY FOG THROUGH 17Z.
&&
.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH TUESDAY...SNOW SHOWERS IN CENTRAL IDAHO
ASSOCIATED WITH AN EXITING UPPER LEVEL TROUGH WILL ALLOW UP TO AN
ADDITIONAL 2 INCHES ACCUMULATION IN EASTERN VALLEY COUNTY AND THE
BOISE MOUNTAINS AND UP TO AN INCH OF WET SNOW GRASSY/BARE AREAS IN
THE WESTERN MAGIC VALLEY...UNTIL AROUND 6 PM. LOCALLY GUSTY WEST
WINDS TO 35 MPH LOOK TO DIMINISH TO LIGHT EARLY THIS EVENING EXCEPT
IN THE MAGIC VALLEY WHERE 15-20 MPH SUSTAINED WIND ARE EXPECTED
TONIGHT. SO PATCHY FOG IS POSSIBLE WHERE WINDS DROP OFF. QUICK
MOVING STORM WILL LEAVE COOL NW FLOW AND DRYING ACROSS THE REGION
THROUGH MONDAY NOON RESULTING TEMPERATURES 3-5F BELOW NORMAL THOUGH
HIGH ELEVATION SHELTERED AREAS /I.E. FAFI1/ COULD SEE SINGLE DIGIT
LOWS THE NEXT COUPLE NIGHTS. A SYSTEM THAT BRUSHES PRECIP NORTH OF
US IS EXPECTED TO BRING SOME CLOUDS ACROSS SE OREGON AND SW IDAHO
MONDAY AFTERNOON AND FAR NORTHERN ZONES TUESDAY AS A RIDGE/INVERSION
BUILDS NORTHWARD INTO THE AREA. COULD SEE STRATUS EARLY TUESDAY
MORNING IN THE UPPER WEISER ZONE WHERE SNOW ACCUMULATED AND INTO THE
OREGON LOWER TREASURE VALLEY WHERE DIURNAL WINDS TEND TO ACCUMULATE
SUCH LOW LEVEL MOISTURE.
LONG TERM...TUESDAY NIGHT THROUGH SUNDAY...SHORTWAVE RIDGE WILL KEEP
INVERSION IN PLACE THROUGH THURSDAY. RESULT WILL BE ABOVE NORMAL
TEMPS IN THE MOUNTAINS WITH COLDER AIR TRAPPED IN THE VALLEYS.
MODELS HAVE HINT OF A SE WIND IN BOISE WHICH COULD BE ENOUGH TO KEEP
FOG/STRATUS OUT OF THE CITY. LOOKS LIKE A BETTER CHANCE IN LOWER
TREASURE/WEISER AND BAKER VALLEYS FOR WEDNESDAY AND THURSDAY MORNING
WITH LITTLE WIND. WHILE INVERSION REMAINS IN PLACE ON THURSDAY...
SURFACE WINDS WILL INCREASE DURING THE DAY HELPING TO SCOUR OUT THE
FOG/STRATUS IN MOST LOCATIONS. SHORTWAVE MOVES INTO THE REGION ON
FRIDAY BRINGING CHANCE OF SNOW TO THE MTNS AND RAIN TO THE VALLEYS.
CONDITIONS DRY OUT FOR SAT/SUN IN N-NW FLOW WITH NEAR NORMAL TEMPS.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.
&&
$$
WEATHER.GOV/BOISE
DISCUSSION...BW
AVIATION.....JA
PREV SHORT TERM...VM
PREV LONG TERM....DG/DD
000
FXUS66 KPDT 222303 AAA
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
302 PM PST SUN NOV 22 2009
UPDATED AVIATION DISCUSSION
.SHORT TERM...TONIGHT THROUGH TUESDAY...UPPER LEVEL LOW CENTER OVER
NORTHEAST WASHINGTON AT THIS HOUR WITH SURFACE LOW TRAILING SLIGHTLY
BEHIND ACROSS NORTH CENTRAL WASHINGTON. HAVE SEEN WIDESPREAD
ADVISORY WINDS TODAY WITH LOCALLY STRONGER GUSTS NEARING 60 MPH
NOTED JUST TODAY. OTHER STRONG WINDS HAVE BEEN REPORTED ALONG WITH
SOME DOWNED TREES AS WELL. REFER TO LOCAL STORM REPORTS FOR FURTHER
DETAILS. MANY WIND ADVISORIES AND WINTER WEATHER ADVISORIES WILL BE
ALLOWED TO EXPIRE AT 4 PM AS PLANNED WITH THE WIND ADVISORIES ALONG
THE FOOTHILLS AND THE WINTER WEATHER STATEMENTS FOR THE BLUE
MOUNTAINS LIKELY TO CONTINUE THROUGH THEIR PLANNED EXPIRATION OF 7
PM TONIGHT. SINCE THE PAIR OF LOW CIRCULATIONS HAVE PROGRESSED
SLIGHTLY FURTHER NORTH THAN EXPECTED, SNOW AMOUNTS OVER THE BLUE
MOUNTAINS HAVE BEEN ON THE LIGHT SIDE, BUT ACCUMULATION RATES HAVE
PICKED UP OVER THE LAST FEW HOURS, THUS WILL WAIT AND SEE.
WINDS AND PRECIPITATION WILL CONTINUE TO DECREASE ACROSS THE REGION
AS THE SYSTEM MOVES FURTHER EAST. EXPECT SOME LIGHT SNOW SHOWERS
WILL CONTINUE OVERNIGHT NEAR THE CASCADE CREST AND OVER THE
NORTHEASTERN MOUNTAINS BUT ACCUMULATIONS SHOULD BE FAIRLY LIGHT.
MONDAY WILL BE A RELATIVELY CALM DAY AS FLAT HIGH PRESSURE
CROSSES OVER THE REGION. THE SOUTHERN EDGE OF A COLD FRONT WILL CLIP
THE NORTHEASTERN THIRD OF THE CWA MONDAY NIGHT AND TUESDAY POSSIBLY
BRINGING ANOTHER COUPLE INCHES OF SNOW TO THE WASHINGTON CASCADE
EAST SLOPES AND NORTHEASTERN MOUNTAINS. THAT REALLY SEEMS TO BE THE
ONLY IMPACT THOUGH. IT APPEARS MOST OF THE REGION IS UNDER THE
CASCADE SHADOW INFLUENCE AND WILL REMAIN DRY. TEMPERATURES WILL
GENERALLY REMAIN ON THE COOLER SIDE AS WELL. /JBONK
.LONG TERM...TUESDAY NIGHT THROUGH SUNDAY...AN UPPER RIDGE WILL
BUILD OVER EASTERN WASHINGTON AND OREGON TUESDAY NIGHT. SUBSIDENCE
FROM THE RIDGE WILL WILL PROVIDE CLEARING SKIES AND LIGHT WINDS
WITH STRONG SURFACE INVERSIONS TUESDAY NIGHT. IN THE LOWER COLUMBIA
BASIN PATCHY FOG AND FREEZING FOG WILL FORM AT NIGHT UNDER THE
INVERSIONS AND KEEP DAYTIME TEMPERATURES WEDNESDAY BELOW NORMAL. THE
FOG WILL FORM MAINLY ALONG THE LARGE RIVERS AND STREAMS AND THEN
GRADUALLY EXPAND IN COVERAGE WEDNESDAY NIGHT AND THURSDAY. AT HIGHER
ELEVATIONS THE SURFACE INVERSIONS WILL BREAK DURING THE DAY AND
WARMER AIR ALOFT ASSOCIATED WITH THE RIDGE WILL REACH THE SURFACE TO
PRODUCE LARGE DIURNAL TEMPERATURE SPREADS. A COLD FRONT WILL MOVE
INLAND THURSDAY AFTERNOON AND BRING ANOTHER ROUND OF PRECIPITATION
TO THE FORECAST AREA THURSDAY NIGHT AND FRIDAY. MORE SYSTEMS WILL
MOVE THROUGH SATURDAY AND SUNDAY. COONFIELD
&&
.AVIATION...0Z TAFS...VFR CONDITIONS WILL PREVAIL AT ALL LOCATIONS.
STRONG SOUTHWEST TO WEST 12 TO 25 KTS WILL DIMINISH OVERNIGHT. 76
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 32 46 37 41 / 10 10 20 10
ALW 34 47 36 42 / 10 10 20 10
PSC 29 45 35 45 / 10 10 10 10
YKM 24 42 31 49 / 10 10 20 10
HRI 28 45 32 45 / 10 10 10 10
ELN 27 40 27 40 / 10 10 30 10
RDM 20 46 25 47 / 10 10 10 10
LGD 25 40 30 42 / 20 10 20 20
GCD 21 44 25 52 / 10 10 10 10
DLS 33 45 35 49 / 20 10 40 20
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR ORZ041-044.
HIGH WIND WARNING UNTIL 4 PM PST THIS AFTERNOON FOR ORZ042.
WIND ADVISORY UNTIL 7 PM PST THIS EVENING FOR ORZ501-504.
WINTER STORM WARNING UNTIL 7 PM PST THIS EVENING FOR ORZ502.
WINTER WEATHER ADVISORY UNTIL 7 PM PST THIS EVENING FOR ORZ503.
WA...WINTER WEATHER ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR WAZ501-
502.
WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR WAZ024-028-502.
WIND ADVISORY UNTIL 7 PM PST THIS EVENING FOR WAZ029.
WINTER STORM WARNING UNTIL 7 PM PST THIS EVENING FOR WAZ030.
&&
THREAT INDEX
MONDAY : GREEN
TUESDAY : GREEN
WEDNESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
87/76/76
000
FXUS66 KMFR 222250
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
250 PM PST SUN NOV 22 2009
.DISCUSSION...COLD AIR ALOFT COMBINED WITH WEAKENING DYNAMICS AND
SOME UPSLOPE FLOW IS CAUSING SNOW SHOWERS OVER THE CASCADES WITH
ISOLATED RAIN SHOWERS IN THE COASTAL AREAS. UPSTREAM...A RIDGE IS
BUILDING AHEAD OF A STORM SYSTEM THAT WILL RIDE INTO THE GULF OF
ALASKA. THIS WILL REFLECT AS HIGH PRESSURE ON THE
SURFACE...INCREASING STABILITY OVER THE REGION AND ENDING ANY
SHOWERS. LIGHT WINDS...LONG NIGHTS...SURFACE HIGH PRESSURE AND
RECENT RAIN AND SNOWFALL IS A PERFECT SCENARIO FOR FOG DEVELOPING
IN THE VALLEYS IN THE WEST AND EAST SIDE. MONDAY THROUGH WEDNESDAY
WILL FEATURE FOG FORMING AFTER MIDNIGHT IN FAVORED VALLEYS. THE
FOG WILL LIFT TO LOW CLOUDS AND EVENTUALLY CLEAR AROUND NOON IN
MOST LOCATIONS. TUESDAY A WEAK COLD FRONT BRUSHES THE COASTAL
ZONES...BUT RAIN CHANCES ARE VERY LOW. CLEARING TIME WILL DICTATE
HOW WARM TEMPERATURES GET DURING THE FIRST HALF OF THE WEEK. CURRENT
FORECAST PRESENTS THE IDEA THAT WEDNESDAY WILL BE THE WARMEST DAY
AS GFS AND NAM AGREE THAT AIRMASS MAY BE 1-2 STANDARD DEVIATIONS
ABOVE AVERAGE BY THAT TIME. CLOUDS WILL BE MOSTLY OF THE MID AND
HIGH VARIETY THIS WEEK.
WEATHER FOR THANKSGIVING DAY TRAVEL IS GRADUALLY COMING INTO
FOCUS. GFS ENSEMBLE MEMBERS ALL INDICATE A SIMILAR IDEA OF AN
UPPER TROUGH AND COLD FRONT AFFECTING NORTHERN CALIFORNIA AND
OREGON BY THURSDAY AFTERNOON. SNOW LEVELS WILL INITIALLY BE
BETWEEN 5000 TO 7000 FEET BUT WILL FALL THURSDAY NIGHT AND END UP
AROUND 3500 FEET FRIDAY MORNING. THE ECMWF INDICATES MORE MOISTURE
THAN THE GFS SO WILL NEED TO MONITOR TRENDS IN THE NEAR-TERM. SISKIYOU PASS
WILL NOT LIKELY HAVE SIGNIFICANT SNOW IMPACTS WITH THIS WEATHER
SYSTEM. HOWEVER...AS COLD AIR FOLLOWS THE COLD FRONT...SOME SNOW
MAY ACCUMULATE AT PASS LEVEL LATE THURSDAY NIGHT OR EARLY FRIDAY
MORNING.
&&
.AVIATION...VFR CONDITIONS ARE EXPECTED TO CONTINUE AT ALL TAF
SITES THROUGH LATE TONIGHT WHEN FOG FORMS AT RBG AND
MFR...RESULTING IN IFR CONDITIONS THAT SHOULD LAST THROUGH MIDDAY
MONDAY. MOUNTAIN OBSCURATION WILL CONTINUE TO IMPACT MOST OF THE
HIGH TERRAIN THROUGH ABOUT 06Z WHEN DRY AIR BEGINS TO FILTER INTO
THE ELEVATED AREAS AND CLOUDS THERE DIMINISH.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...HAZARDOUS SEAS WARNING UNTIL 4 AM PST MONDAY
FOR PZZ350-PZZ356-PZZ370-PZZ376.
$$
KEENE
000
FXUS66 KPDT 222226
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
226 PM PST SUN NOV 22 2009
.SHORT TERM...TONIGHT THROUGH TUESDAY...UPPER LEVEL LOW CENTER OVER
NORTHEAST WASHINGTON AT THIS HOUR WITH SURFACE LOW TRAILING SLIGHTLY
BEHIND ACROSS NORTH CENTRAL WASHINGTON. HAVE SEEN WIDESPREAD
ADVISORY WINDS TODAY WITH LOCALLY STRONGER GUSTS NEARING 60 MPH
NOTED JUST TODAY. OTHER STRONG WINDS HAVE BEEN REPORTED ALONG WITH
SOME DOWNED TREES AS WELL. REFER TO LOCAL STORM REPORTS FOR FURTHER
DETAILS. MANY WIND ADVISORIES AND WINTER WEATHER ADVISORIES WILL BE
ALLOWED TO EXPIRE AT 4 PM AS PLANNED WITH THE WIND ADVISORIES ALONG
THE FOOTHILLS AND THE WINTER WEATHER STATEMENTS FOR THE BLUE
MOUNTAINS LIKELY TO CONTINUE THROUGH THEIR PLANNED EXPIRATION OF 7
PM TONIGHT. SINCE THE PAIR OF LOW CIRCULATIONS HAVE PROGRESSED
SLIGHTLY FURTHER NORTH THAN EXPECTED, SNOW AMOUNTS OVER THE BLUE
MOUNTAINS HAVE BEEN ON THE LIGHT SIDE, BUT ACCUMULATION RATES HAVE
PICKED UP OVER THE LAST FEW HOURS, THUS WILL WAIT AND SEE.
WINDS AND PRECIPITATION WILL CONTINUE TO DECREASE ACROSS THE REGION
AS THE SYSTEM MOVES FURTHER EAST. EXPECT SOME LIGHT SNOW SHOWERS
WILL CONTINUE OVERNIGHT NEAR THE CASCADE CREST AND OVER THE
NORTHEASTERN MOUNTAINS BUT ACCUMULATIONS SHOULD BE FAIRLY LIGHT.
MONDAY WILL BE A RELATIVELY CALM DAY AS FLAT HIGH PRESSURE
CROSSES OVER THE REGION. THE SOUTHERN EDGE OF A COLD FRONT WILL CLIP
THE NORTHEASTERN THIRD OF THE CWA MONDAY NIGHT AND TUESDAY POSSIBLY
BRINGING ANOTHER COUPLE INCHES OF SNOW TO THE WASHINGTON CASCADE
EAST SLOPES AND NORTHEASTERN MOUNTAINS. THAT REALLY SEEMS TO BE THE
ONLY IMPACT THOUGH. IT APPEARS MOST OF THE REGION IS UNDER THE
CASCADE SHADOW INFLUENCE AND WILL REMAIN DRY. TEMPERATURES WILL
GENERALLY REMAIN ON THE COOLER SIDE AS WELL. /JBONK
.LONG TERM...TUESDAY NIGHT THROUGH SUNDAY...AN UPPER RIDGE WILL
BUILD OVER EASTERN WASHINGTON AND OREGON TUESDAY NIGHT. SUBSIDENCE
FROM THE RIDGE WILL WILL PROVIDE CLEARING SKIES AND LIGHT WINDS
WITH STRONG SURFACE INVERSIONS TUESDAY NIGHT. IN THE LOWER COLUMBIA
BASIN PATCHY FOG AND FREEZING FOG WILL FORM AT NIGHT UNDER THE
INVERSIONS AND KEEP DAYTIME TEMPERATURES WEDNESDAY BELOW NORMAL. THE
FOG WILL FORM MAINLY ALONG THE LARGE RIVERS AND STREAMS AND THEN
GRADUALLY EXPAND IN COVERAGE WEDNESDAY NIGHT AND THURSDAY. AT HIGHER
ELEVATIONS THE SURFACE INVERSIONS WILL BREAK DURING THE DAY AND
WARMER AIR ALOFT ASSOCIATED WITH THE RIDGE WILL REACH THE SURFACE TO
PRODUCE LARGE DIURNAL TEMPERATURE SPREADS. A COLD FRONT WILL MOVE
INLAND THURSDAY AFTERNOON AND BRING ANOTHER ROUND OF PRECIPITATION
TO THE FORECAST AREA THURSDAY NIGHT AND FRIDAY. MORE SYSTEMS WILL
MOVE THROUGH SATURDAY AND SUNDAY. COONFIELD
&&
.AVIATION...18Z TAFS...INCREASING CEILINGS AS THE COLD FRONT MOVES
THROUGH THIS MORNING. MVFR CONDITIONS AT TIMES DUE TO PASSING RAIN
AND SHOW SHOWERS. STRONG SOUTHWEST 20 TO 40 KTS WILL BE COMMON THIS
MORNING AT MOST STATIONS BUT WILL SLOWLY DIMINISH THROUGH THE DAY.
AFTER 0Z DECREASING WINDS WITH VFR CONDITIONS WILL PREVAIL AT
ALL LOCATIONS. 76
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 32 46 37 41 / 10 10 20 10
ALW 34 47 36 42 / 10 10 20 10
PSC 29 45 35 45 / 10 10 10 10
YKM 24 42 31 49 / 10 10 20 10
HRI 28 45 32 45 / 10 10 10 10
ELN 27 40 27 40 / 10 10 30 10
RDM 20 46 25 47 / 10 10 10 10
LGD 25 40 30 42 / 20 10 20 20
GCD 21 44 25 52 / 10 10 10 10
DLS 33 45 35 49 / 20 10 40 20
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR ORZ041-044.
HIGH WIND WARNING UNTIL 4 PM PST THIS AFTERNOON FOR ORZ042.
WIND ADVISORY UNTIL 7 PM PST THIS EVENING FOR ORZ501-504.
WINTER STORM WARNING UNTIL 7 PM PST THIS EVENING FOR ORZ502.
WINTER WEATHER ADVISORY UNTIL 7 PM PST THIS EVENING FOR ORZ503.
WA...WINTER WEATHER ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR WAZ501-
502.
WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR WAZ024-028-502.
WIND ADVISORY UNTIL 7 PM PST THIS EVENING FOR WAZ029.
WINTER STORM WARNING UNTIL 7 PM PST THIS EVENING FOR WAZ030.
&&
THREAT INDEX
MONDAY : GREEN
TUESDAY : GREEN
WEDNESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
87/76/76
000
FXUS66 KPQR 222217
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
216 PM PST SUN NOV 22 2009
.SYNOPSIS...SHOWERS CONTINUE TO SPREAD OVER THE FORECAST AREA IN COLD
UNSTABLE WESTERLY FLOW ALOFT. HIGH PRES WILL BUILD OVER WESTERN
OREGON LATER TODAY AND TONIGHT. A WARM FRONT OFF THE COAST ON MON
WILL LIFT NE TOWARDS NW OREGON AND WESTERN WA...THEN STALL ON TUE.
WED THE FRONT WILL FINALLY LIFT N INTO WA...BEFORE A COLD FRONT
PUSHES SE THROUGH THE REGION LATE THU.
&&
.SHORT TERM...SATELLITE IMAGERY SHOWS A LARGE AREA OF SHOWERS OVER
THE PACIFIC SPREADING OVER THE FORECAST AREA IN COLD UNSTABLE
WESTERLY FLOW ALOFT. DOPPLER RADAR SHOWS THE SHOWER ACTIVITY
CONTINUING...WITHOUT A LOT OF CHANGES IN INTENSITY...HOWEVER THEY ARE
BECOMING A LITTLE MORE SCATTERED. LIGHTNING DETECTION DATA HAS SHOWN
A FEW LIGHTNING STRIKES AND HAVE HAD A FEW REPORTS OF SMALL HAIL THIS
AFTERNOON. OROGRAPHICS WILL CONTINUE TO WEAKEN THIS AFTERNOON AS H8
FLOW WEAKENS...SO EXPECT SNOW ACCUMULATIONS TO DROP OFF CONSIDERABLY
AND WILL PROBABLY DROP THE WINTER STORM WARNING WITH THE AFTERNOON
PACKAGE. POST FRONTAL SHOWERS DROP OFF QUICKLY TONIGHT...LAST ON THE
N PART OF THE CASCADES.
AN AREA OF WARM AIR ADVECTION SETS UP OVER THE NW PART OF THE
FORECAST AREA MON...AND CONTINUES INTO TUE. A WEAK SHORTWAVE MOVES
ACROSS THE TOP OF THE DEVELOPING UPPER RIDGE TUE...BRINGING THE BEST
CHANCE FOR OVERRUNNING PRECIPITATION TO THE NW PART OF THE AREA ON
MON NIGHT WITH THE SHORT WAVE MOVING THROUGH THE FORECAST AREA
WEDNESDAY.
.LONG TERM...MODELS IN SOME AGREEMENT ON BRINGING A FRONTAL SYSTEM
AND ITS ASSOCIATED UPPER LEVEL TROF THROUGH THE REGION THU/THU NIGHT
FOR A RETURN TO WET WEATHER. AFTER THIS SYSTEM MOVES THROUGH...THE
WEAK HIGH PRES RIDGE REASSERTS ITSELF OVER THE FORECAST
AREA...KEEPING MOST ENERGY NORTH OF FORECAST AREA.
&&
.AVIATION...MOSTLY VFR CONDITIONS WITH PLENTY OF SHOWERS MOST VFR
THOUGH ISOLATED MVFR. SHOWERS SHOULD BEGIN TO TAPER OFF TONIGHT AS
HIGH PRESSURE BUILDS IN. PRESSURE GRADIENT STAYS STRONG ENOUGH TO
KEEP AREA MIXY TONIGHT DIMINISHING ANY CHANCES FOR FOG AND SOUTH
VALLEY MAY BE A LITTLE CLEARER BUT DRY AIR IS FILTERING INTO THE
REGION AND THIS WILL LIKELY KEEP THEM FOG FREE AS WELL. NEXT
SYSTEM BEGINS TO MOVE IN MONDAY AFTERNOON WITH RAIN STARTING AFTER
18Z ON THE COAST.
KPDX AND APPROACHES...VFR FOR THROUGH 12Z EXCEPT FOR ISOLATED MVFR
SHOWERS THEN INCREASING CHANCE FOR MVFR STRATUS MON MORNING AND THEN
THE NEXT FRONT APPROACHES AND WILL LIKELY SEE MVFR CIGS MON
AFTERNOON. WOLFE
&&
.MARINE...SOLID SMALL CRAFT WINDS WILL LET UP TONIGHT AND THEN
INCREASE AGAIN TO NEAR GALE BY TOMORROW MIDDAY WITH GUSTS NEAR 40 KT
BY TOMORROW AFTERNOON. SEAS AT 18 FT AND WILL DROP TONIGHT TO NEAR
11 FT BEFORE BUILDING TO THE MID TEENS ON MONDAY EVENING. WOLFE
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
WA/OR...GALE WATCH MONDAY MORNING THROUGH MONDAY AFTERNOON CAPE
SHOALWATER TO CASCADE HEAD.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CAPE SHOALWATER TO
FLORENCE THROUGH MONDAY MORNING.
SMALL CRAFT ADVISORY FOR WINDS CAPE SHOALWATER TO
FLORENCE THROUGH MONDAY MORNING.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR CONDITIONS
THROUGH MON NIGHT.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS65 KBOI 222202
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
302 PM MST SUN NOV 22 2009
.SHORT TERM...TONIGHT THROUGH TUESDAY...SNOW SHOWERS IN CENTRAL
IDAHO ASSOCIATED WITH AN EXITING UPPER LEVEL TROUGH WILL ALLOW UP
TO AN ADDITIONAL 2 INCHES ACCUMULATION IN EASTERN VALLEY COUNTY AND
THE BOISE MOUNTAINS AND UP TO AN INCH OF WET SNOW GRASSY/BARE
AREAS IN THE WESTERN MAGIC VALLEY...UNTIL AROUND 6 PM. LOCALLY
GUSTY WEST WINDS TO 35 MPH LOOK TO DIMINISH TO LIGHT EARLY THIS
EVENING EXCEPT IN THE MAGIC VALLEY WHERE 15-20 MPH SUSTAINED WIND
ARE EXPECTED TONIGHT. SO PATCHY FOG IS POSSIBLE WHERE WINDS DROP
OFF. QUICK MOVING STORM WILL LEAVE COOL NW FLOW AND DRYING
ACROSS THE REGION THROUGH MONDAY NOON RESULTING TEMPERATURES 3-5F
BELOW NORMAL THOUGH HIGH ELEVATION SHELTERED AREAS /I.E. FAFI1/
COULD SEE SINGLE DIGIT LOWS THE NEXT COUPLE NIGHTS. A SYSTEM THAT
BRUSHES PRECIP NORTH OF US IS EXPECTED TO BRING SOME CLOUDS ACROSS
SE OREGON AND SW IDAHO MONDAY AFTERNOON AND FAR NORTHERN ZONES
TUESDAY AS A RIDGE/INVERSION BUILDS NORTHWARD INTO THE AREA. COULD
SEE STRATUS EARLY TUESDAY MORNING IN THE UPPER WEISER ZONE WHERE
SNOW ACCUMULATED AND INTO THE OREGON LOWER TREASURE VALLEY WHERE
DIURNAL WINDS TEND TO ACCUMULATE SUCH LOW LEVEL MOISTURE.
.LONG TERM...TUESDAY NIGHT THROUGH SUNDAY...SHORTWAVE RIDGE WILL KEEP
INVERSION IN PLACE THROUGH THURSDAY. RESULT WILL BE ABOVE NORMAL
TEMPS IN THE MOUNTAINS WITH COLDER AIR TRAPPED IN THE VALLEYS.
MODELS HAVE HINT OF A SE WIND IN BOISE WHICH COULD BE ENOUGH TO KEEP
FOG/STRATUS OUT OF THE CITY. LOOKS LIKE A BETTER CHANCE IN LOWER
TREASURE/WEISER AND BAKER VALLEYS FOR WEDNESDAY AND THURSDAY MORNING
WITH LITTLE WIND. WHILE INVERSION REMAINS IN PLACE ON THURSDAY...
SURFACE WINDS WILL INCREASE DURING THE DAY HELPING TO SCOUR OUT THE
FOG/STRATUS IN MOST LOCATIONS. SHORTWAVE MOVES INTO THE REGION ON
FRIDAY BRINGING CHANCE OF SNOW TO THE MTNS AND RAIN TO THE VALLEYS.
CONDITIONS DRY OUT FOR SAT/SUN IN N-NW FLOW WITH NEAR NORMAL TEMPS.
&&
.AVIATION...LOCAL IFR IN THE SW IDAHO MTNS AND MVFR IN THE WESTERN
MAGIC VALLEY THIS AFTERNOON WILL GRADUALLY IMPROVE THIS EVENING.
ISOLATED IFR IN THE MTNS OVERNIGHT DUE TO LOW CEILINGS...OTHERWISE
VFR TONIGHT AND MONDAY. SURFACE WINDS GENERALLY DECREASING TO 10 KTS
OR LESS FOR MONDAY. WINDS ALOFT DECREASE TO 20 KTS OR LESS BELOW 10K
FEET MSL.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.
&&
$$
WEATHER.GOV/BOISE
SHORT TERM...VM
LONG TERM....DG/DD
AVIATION.....DG
000
FXUS66 KPDT 221731
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
931 AM PST SUN NOV 22 2009
.UPDATE...SOUTHWEST TO WEST WINDS ARE PICKING UP AS THE SURFACE
LOW HAS STARTED TO CROSS THE CASCADES. HAVE RECEIVED REPORTS OF
ADVISORY LEVEL GUSTS ACROSS THE FAR SOUTHERN END OF THE YAKIMA
VALLEY. HAVE ADDED A WIND ADVISORY FOR THE YAKIMA VALLEY THINKING
WINDS WILL CONTINUE DOWN-SLOPING INTO THE WESTERN VALLEY AS WELL.
WILL LET THE HIGH WIND WARNING EXPIRE AS PLANNED FOR WALLOWA
COUNTY AND THE GRANDE RONDE VALLEY AS WINDS WILL CONTINUE TO
DECREASE AND REMAIN BELOW WARNING LEVELS FOR THE REST OF THE DAY.
THE REMAINING WARNING FOR NORTH CENTRAL OREGON AND THE REMAINING
ADVISORIES APPEAR TO BE ON TRACK FOR NOW SO WILL LET THEM CONTINUE.
STILL SEEING SHOWERS CROSS THE OREGON CREST RATHER EASILY WITH
SNOW LEVEL HOVERING BETWEEN 2500 AND 3500 FEET. A QUICK INCH OF
ADDITIONAL ACCUMULATION COULD COME FROM ANY PARTICULAR SHOWER
ACROSS CENTRAL OREGON SO WILL LET THE ADVISORY CONTINUE. SEEING
MORE STRATIFORM PRECIPITATION CONTINUE ALONG THE WASHINGTON
CASCADES AND STILL THINK MOST ACCUMULATION WILL BE NEAR THE CREST
WITH THE ADVISORIES CONTINUING AS PLANNED AS WELL. MODELS
CONTINUE TO INDICATE THE BULK OF SNOWFALL ACROSS THE BLUE
MOUNTAINS WILL FALL OVER THE NEXT FEW HOURS SO WILL CONTINUE THE
WARNINGS AND ADVISORY ALTHOUGH ACCUMULATIONS THUS FAR OVER THE
NORTHERN BLUES HAVE BEEN DISAPPOINTING.
UPDATES WILL BE OUT SHORTLY. /JBONK
&&
.AVIATION...18Z TAFS...INCREASING CEILINGS AS THE COLD FRONT MOVES
THROUGH THIS MORNING. MVFR CONDITIONS AT TIMES DUE TO PASSING RAIN
AND SHOW SHOWERS. STRONG SOUTHWEST 20 TO 40 KTS WILL BE COMMON THIS
MORNING AT MOST STATIONS BUT WILL SLOWLY DIMINISH THROUGH THE DAY.
AFTER 0Z DECREASING WINDS WITH VFR CONDITIONS WILL PREVAIL AT
ALL LOCATIONS. 76
&&
.PREV DISCUSSION... /ISSUED 340 AM PST SUN NOV 22 2009/
SHORT TERM...TODAY THROUGH MONDAY...A VIGOROUS STORM SYSTEM
CONTINUES TO MOVE ONSHORE THIS MORNING. THE SURFACE LOW IS NOW OVER
SOUTHWEST WASHINGTON...FAIRLY CLOSE TO THE NAM FORECAST POSITION. A
WARM FRONT...EXTENDING FROM THE TRIPLE POINT NEAR STAMPEDE PASS
SOUTHEAST INTO EAST-CENTRAL OREGON...IS SWINGING NORTHEAST AND EAST.
EXPECT THIS FRONT TO EXIT OUR AREA IN THE NEXT COUPLE OF HOURS.
MEANWHILE THE COLD FRONT HAS STARTED TO JUMP THE CASCADE CREST AND
SHOULD BE THROUGH A GOOD PORTION OF OUR AREA BY DAYBREAK. WILL
CONTINUE ALL CURRENT WARNINGS AND ADVISORIES AS THEY ARE...BUT DID
HAVE TO ADD A SNOW ADVISORY FOR THE CENTRAL OREGON ZONE EARLIER AS
AREAS ABOVE 3500 FEET WERE GETTING A GOOD DUMP OF SNOW. SNOW IS
FALLING AT YAKIMA AND ELLENSBURG. AT THIS TIME IT LOOKS THAT THEY
WILL SEE UP TO 2 INCHES...BUT THE COLD FRONT SHOULD BE THROUGH THESE
TWO LOCATIONS BY 5 AM (POSSIBLY EARLIER). THIS WILL TURN FLOW
WESTERLY AND SIGNIFICANTLY REDUCE PRECIP AND MAY ALSO MIX OUT
TRAPPED COLD AIR AND RAISE THE SNOW LEVELS.
HIGH PRESSURE WILL BUILD INTO THE REGION TONIGHT RESULTING IN WIND
DOWN IN POST SYSTEM SHOWERS. IT WILL ALSO ALLOW FOR SOME CLEARING OF
THE SKIES FOR COOLER OVERNIGHT LOW TEMPS. A WEAK WAVE WILL RIDE OVER
THE UPPER LEVEL HIGH PRESSURE RIDGE OVER THE AREA MONDAY. THIS WAVE
MAY SPREAD SOME LIGHT SNOW OR RAIN INTO THE WASHINGTON CASCADE EAST
SLOPE AREAS. ELSEWHERE CONDITIONS WILL BE DRY. 90
LONG TERM...MONDAY NIGHT THROUGH NEXT SATURDAY...AN UPPER RIDGE
WILL BEGIN TO BUILD OVER THE PACIFIC NORTHWEST MONDAY NIGHT AND
TUESDAY. THIS WILL CAUSE MOST OF THE MOISTURE WITH ANY WEATHER
SYSTEMS TO BE PUSHED NORTHWARD NORTH OF THE UPPER JET STREAM INTO
FAR NORTHWEST WASHINGTON AND SOUTHWEST CANADA. THIS WILL SPARE THE
FORECAST AREA FROM ANY SIGNIFICANT WEATHER EVENTS THROUGH MOST OF
THE WEEK AS THE UPPER RIDGE STRENGTHENS. HOWEVER WITH THE UPPER
RIDGE DEVELOPING AND THE PRESENCE OF THE RECENT PRECIPITATION PATCHY
VALLEY FOG AND FREEZING FOG WILL DEVELOP OVER THE LOWER COLUMBIA
BASIN AND ADJACENT VALLEYS. IT WILL FORM MAINLY ALONG THE LARGE
RIVERS AND STREAMS AT FIRST AND THEN GRADUALLY EXPAND IN COVERAGE BY
WEDNESDAY AND WILL PERSIST THROUGH THURSDAY. AND PRECIPITATION WILL
BE MAINLY LIGHT RAIN AND SNOW SHOWERS OVER THE MOUNTAINS. A COLD
FRONT WITH A WEATHER SYSTEM WILL APPROACH THE CWA LATE THURSDAY INTO
FRIDAY BRINGING THE NEXT BETTER CHANCE OF PRECIPITATION TO THE
FORECAST AREA BY FRIDAY INTO SATURDAY. TEMPERATURES WILL BE NEAR TO
ABOVE NORMAL IN HIGHER TERRAIN AND NEAR TO BELOW NORMAL IN THE LOWER
TERRAIN THAT IS CAUGHT UNDER TEMPERATURE INVERSIONS AND/OR WITH
FOG/LOW CLOUDS. 88
AVIATION...12Z TAFS...LIFR TO IFR CONDITIONS WILL PREVAIL AT KRDM
AND KYKM AT TIMES DUE TO SNOW OR A MIX OF RAIN AND SNOW WITH LOW
CEILINGS. A COLD FRONT WILL PASS THESE AREAS ALLOWING PRECIPITATION
TO DECREASE WITH INCREASING CEILINGS...WHICH WILL ALLOW MVFR TO VFR
CONDITIONS TO RETURN FOR MOST OF THE TIME WITH OCCASIONAL PERIODS
OF IFR DUE TO PASSING RAIN AND SHOW SHOWERS. ELSEWHERE MAINLY VFR
CONDITIONS WILL PREVAIL BUT THERE WILL BE PERIODS OF IFR TO MVFR DUE
TO RAIN OR SNOW SHOWERS WITH LOWERED CEILINGS THIS MORNING...WITH
IMPROVING CONDITIONS THIS AFTERNOON. STRONG SOUTH TO EAST WINDS OF
AT LEAST 25 TO 40 KTS WILL BE COMMON EARLY THIS MORNING AT MOST
STATIONS BUT WILL SLOWLY DIMINISH THROUGH THE DAY INTO TONIGHT AND
TURN TO THE SOUTHWEST TO WEST. TONIGHT DECREASING WINDS WITH VFR
CONDITIONS WILL PREVAIL AT ALL LOCATIONS. 88
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 47 32 46 37 / 70 10 10 10
ALW 48 34 47 36 / 80 10 10 20
PSC 53 29 45 35 / 60 10 10 20
YKM 48 23 42 31 / 40 10 10 20
HRI 52 28 45 32 / 60 10 10 10
ELN 44 27 40 27 / 60 10 20 30
RDM 45 20 46 25 / 50 10 10 10
LGD 42 25 40 30 / 80 20 10 10
GCD 42 21 44 25 / 60 10 10 10
DLS 49 33 45 35 / 40 20 10 40
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR ORZ041-044.
HIGH WIND WARNING UNTIL 10 AM PST THIS MORNING FOR ORZ049-050.
WINTER STORM WARNING UNTIL 7 PM PST THIS EVENING FOR ORZ502.
HIGH WIND WARNING UNTIL 4 PM PST THIS AFTERNOON FOR ORZ042.
WINTER WEATHER ADVISORY UNTIL NOON PST TODAY FOR ORZ043.
WIND ADVISORY UNTIL 1 PM PST THIS AFTERNOON FOR ORZ043.
WIND ADVISORY UNTIL 7 PM PST THIS EVENING FOR ORZ501-504.
WINTER WEATHER ADVISORY UNTIL 7 PM PST THIS EVENING FOR ORZ503.
WA...WINTER WEATHER ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR WAZ501-
502.
WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR WAZ024-028-502.
WINTER STORM WARNING UNTIL 7 PM PST THIS EVENING FOR WAZ030.
WIND ADVISORY UNTIL 7 PM PST THIS EVENING FOR WAZ027-029.
&&
THREAT INDEX
TODAY : RED
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
87/76
000
FXUS66 KMFR 221709
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
909 AM PST SUN NOV 22 2009
.DISCUSSION...DISCUSSION...FIRST LOOK AT VISIBLE IMAGERY SUGGESTS PARTLY CLOUDY
SKIES ACROSS THE REGION...WITH THE MOST SUN AT THE COAST AND THE
MOST CLOUDS ALONG THE CASCADES AND EAST SIDE. MORNING MFR SOUNDING
SHOWS FAIRLY STABLE CONDITIONS BUT COLD AIR CUMULUS OFFSHORE
SUGGESTS INSTABILITY WILL INCREASE DURING THE LATE MORNING AND
AFTERNOON...FUELING SOME ISOLATED SHOWERS OVER THE HIGHER TERRAIN.
BY TONIGHT...STABILITY WILL INCREASE ACROSS THE REGION AND SKIES
WILL CLEAR SOME...HELPING TO GENERATE FOG IN MANY VALLEYS. THIS
PATTERN WILL CONTINUE THROUGH WEDNESDAY WITH LATE NIGHT AND
MORNING FOG IN THE LOW ELEVATIONS TRANSITIONING TO PARTLY SUNNY
SKIES DURING THE AFTERNOON. CLIMATOLOGY SUGGESTS THAT LOCATIONS
LIKE ROSEBURG AND MEDFORD WILL LIKELY HAVE LOW CLOUDS THROUGH
ABOUT NOON ON MONDAY THROUGH WEDNESDAY.
LOOKING TOWARD THE BUSY THANKSGIVING TRAVEL PERIOD...ECMWF AND GFS
ARE IN BETTER SYNC THAN PREVIOUS DAYS WITH A SOLUTION THAT
INVOLVES A TROUGH REACHING THE OREGON COASTAL WATERS THURSDAY.
PRECIPITATION AMOUNTS LOOK TO BE LIGHT TO MODERATE FOR THIS TIME
OF YEAR. INITIAL LOOK AT SNOW LEVELS SUGGEST THEY WILL BE ABOVE
SISKIYOU PASS LEVEL...ABOUT 5000 FEET. PRECIPITATION TAPERS OFF
DURING THE DAY ON FRIDAY.
&&
.AVIATION...FLYING WEATHER WILL FEATURE MOUNTAIN OBSCURATION TODAY
OVER THE HIGHER TERRAIN WITH MOSTLY VFR CEILINGS AT LOWER
ELEVATIONS. TONIGHT...LOW CLOUDS AND FOG WILL FORM IN THE VALLEYS
AFFECTING RBG AND MFR AFTER 10Z...WITH IFR CONDITIONS LASTING
THROUGH LATE MONDAY MORNING. KEENE
&&
.PREV DISCUSSION... /ISSUED 311 AM PST SUN NOV 22 2009/
DISCUSSION...THE STRONG COLD FRONT IS TRAVERSING OUR REGION AS
INDICATED BY THE 00Z GFS. IT IS ABOUT TO REACH THE CASCADES AND
SHOULD MOVE EAST OF LAKE AND MODOC COUNTIES BY AROUND 10 AM.
PRECIPITATION IS LIGHT TO MODERATE WITH SNOW LEVELS AT 3500 TO
4000 FEET. THERE WERE FEW ADJUSTMENTS TO MAKE TO THE FIRST 24
HOURS OF THE FORECAST. THE WIND AND WINTER WEATHER HEADLINE
PRODUCTS ARE EXPECTED TO REMAIN APPROPRIATE THROUGH THEIR
CURRENTLY SCHEDULED EXPIRATIONS...4 AND 7 AM RESPECTIVELY FOR THE
COASTAL AND SHASTA VALLEY WINDS AND 7 AM FOR THE CASCADE AND EAST
SIDE WINTER WEATHER ADVISORY.
SHOWERS WILL BE NUMEROUS BEHIND THE FRONT THEN GRADUALLY TAPER OFF
FROM LATE MORNING INTO THIS EVENING...WITH EVENING CLEARING
LEADING TO A MUCH COLDER NIGHT AND AREAS OF FREEZING FOG.
THE MAIN UPPER LEVEL FEATURE MONDAY THROUGH WEDNESDAY WILL BE A
HIGH PRESSURE RIDGE CENTERED OFFSHORE FROM CENTRAL AND SOUTHERN
CALIFORNIA. A COUPLE OF WEAK TROUGHS WILL RIDE OVER THE TOP OF THE
RIDGE INTO WASHINGTON AND NORTHERN OREGON. THUS...IT WILL BE DRY
ASIDE FROM A SLIGHT CHANCE OF COASTAL SHOWERS NORTH OF CAPE
BLANCO. THE PROXIMITY OF THE TROUGHS WILL ALLOW PERIODS OF SCATTERED
TO BROKEN HIGH CLOUDS. LATE NIGHT AND MORNING FOG WILL BE
PREVALENT IN WEST SIDE VALLEYS.
POPS HAVE BEEN LOWERED FOR WEDNESDAY NIGHT AND ALSO FOR
THANKSGIVING DAY...ESPECIALLY IN AREAS EAST OF THE CASCADES WITH
THE ECMWF AND GFS COMING INTO CLOSER AGREEMENT ON A SLOWER SOLUTION
WITH THE NEXT COLD FRONT. SNOW LEVELS DO NOT LOOK TO BE ESPECIALLY
LOW WITH THE FRONT...AROUND 5000 TO 5500 FEET WHICH IS HIGHER THAN
NORMAL. GIVEN THAT THE MODELS HAVE JUST NOW COME INTO BETTER
AGREEMENT...I WILL KEEP THURSDAY EVENING INTO FRIDAY MORNING POPS IN
THE CHANCE CATEGORY.
BEYOND FRIDAY...THE ECMWF IS STRONGER THAN THE GFS WITH A RIDGE
BUILDING OVER THE OFFSHORE WATERS. THUS...THE ECMWF SOLUTION FOR
FRIDAY NIGHT THROUGH THE WEEKEND WOULD BE COLDER BUT DRIER. I WILL
CONTINUE WITH A COMPROMISE BETWEEN THE TWO MODELS FOR THE LATTER
PART OF THE FORECAST PERIOD. ANY LIGHT SHOWERS DEPICTED BY THE
GFS WOULD BE MAINLY FROM THE CASCADES WESTWARD.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH SURF ADVISORY UNTIL 3 PM PST THIS AFTERNOON FOR ORZ021-
ORZ022.
CA...NONE.
PACIFIC COASTAL WATERS...HAZARDOUS SEAS WARNING UNTIL 4 AM PST MONDAY
FOR PZZ350-PZZ356-PZZ370-PZZ376.
$$
000
FXUS65 KBOI 221700
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
1000 AM MST SUN NOV 22 2009
.DISCUSSION...WEBCAMS SHOW MANY SNOW COVERED ROADS AS LOW AS 3100
FT MSL IN SE OREGON AND SW IDAHO. RADAR AND SATELLITE IMAGERY AND
SURFACE OBS INDICATE THE COLD FRONT ACROSS CENTRAL OREGON. SNOW
SHOWERS HAVE DECERASED IN COVERAGE IN HARNEY COUNTY WHERE THE
SN/BLSN ADVISORY HAS BEEN DISCONTINUED. A BAND OF HEAVIER SNOW
SHOWERS IS MOVING THROUGH BOISE AND MCCALL. A SPOTTER IN PINE
REPORTED 4 INCHES AS OF 959 AM. GUSTY SE WINDS TO 30 MPH SHIFTING
TO SW/NW BEHIND FRONT STILL ON TRACK. NO OTHER CHANGES THIS
MORNING.
&&
.AVIATION...WIDESPREAD IFR IN SNOW OVER SW IDAHO MTNS THIS MORNING
BECOMING SCATTERED IN COVERAGE THIS AFTERNOON. VFR/MVFR IN LOWER
VALLEYS WITH RAIN/SNOW MIX ENDING FROM WEST TO EAST. IN SE OREGON
WIDELY SCATTERED SNOW SHOWERS AND ACCOMPANYING IFR CONDITIONS INTO
EARLY AFTERNOON. STRONG WINDS SURFACE AND ALOFT TODAY DECREASING
TONIGHT. GUSTS TO 35 KTS AT THE SURFACE WITH WEST WINDS OVER 50 KTS
ALOFT.
&&
.PREV DISCUSSION...
SHORT TERM...VIGOROUS STORM SYSTEM CURRENTLY PUSHING INTO THE
FORECAST AREA WITH SNOW AND WIND. SYSTEM IS FAST MOVING EMBEDDED
WITHIN 120-140 KNOT JETSTREAM CORE...THUS MAIN IMPACTS NOT EXPECTED
TO LAST MORE THAN A FEW HOURS OVER ANY ONE AREA TODAY. HAVE ADDED
HARNEY AND MALHEUR COUNTIES IN OREGON TO THE WINTER WEATHER
ADVISORIES WITH LIGHT TO MODERATE SNOW AND INCREASING WINDS.
SYNOPTICALLY...A WARM FRONT IS MOVING THROUGH SOUTHEAST OREGON WITH
A COLD FRONT ALIGNED NORTH SOUTH JUST EAST OF THE CASCADES. SYSTEM
EXPECTED TO OCCLUDE LATER THIS AFTERNOON OVER OUR AREA AND WEAKEN.
NEVERTHELESS...SEVERAL INCHES OF NEW SNOW CAN BE EXPECTED IN THE
NORTHERN MOUNTAINS WITH 1 TO 3 INCHES IN VALLEYS SOUTH TO THE SNAKE
RIVER. LESS SNOW IS FORECAST SOUTHWARD TOWARD THE NEVADA STATE LINE.
DUE TO THE QUICK MOVEMENT TO THE SYSTEM...HEAVY PRECIP IS NOT
EXPECTED TO LAST FOR A LONG TIME BUT INCREASING WINDS WITH BLOWING
SNOW WILL BE JUST AS IMPORTANT AN IMPACT AS THE ACTUAL SNOW FALL.
TREASURE AND MAGIC VALLEYS A LITTLE MORE TRICKY WITH SOUNDING
PROFILES INDICATING LIGHT SNOW EARLY THIS MORNING FOLLOWED BY A
MIXTURE...THEN TO ALL RAIN BY THIS AFTERNOON AS WINDS TURN WESTERLY
BEHIND FRONT...ALTHOUGH NOT EXPECTING SIGNIFICANT SNOW
ACCUMULATIONS. LINGERING SNOW SHOWERS TO REMAIN TONIGHT IN THE UPPER
TROF AXIS WITH DRIER CONDITIONS ANTICIPATED FOR MONDAY AS YET
ANOTHER RIDGE BUILDS OVER THE AREA.
LONG TERM..MONDAY NIGHT THROUGH SUNDAY...DRY CONDITIONS MONDAY
THROUGH THURSDAY AS AN UPPER LEVEL RIDGE AMPLIFIES OVER NRN
CALIFORNIA/NEVADA. THUS...STRENGTH OF SURFACE INVERSION CONTINUES TO
BE THE MAIN FORECAST CHALLENGE. MODEL SOUNDINGS INDICATE SOME MIXING
TUESDAY AFTERNOON...NOT UNTIL WEDNESDAY DOES INVERSION LOOK TO REACH
ITS FULL POTENTIAL. EXPECT BELOW NORMAL VALLEY TEMPERATURES /ABOVE
NORMAL TEMPS IN MTN VALLEYS/ AND FOG ON WEDNESDAY...AND POSSIBLY
EVEN THURSDAY. MODELS IN BETTER AGREEMENT WITH AN UPPER LEVEL TROUGH
PROGGED TO MOVE INTO THE FORECAST AREA EARLY FRIDAY. EXPECT CHANCES
FOR VALLEY RAIN/SNOW AND MOUNTAIN SNOW ON FRIDAY...THEN DRIER ON
SATURDAY AND SUNDAY AS SYSTEM QUICKLY EXITS THE FORECAST AREA.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...WINTER WEATHER ADVISORY UNTIL 2 PM MST THIS AFTERNOON FOR IDZ011-
IDZ013-IDZ033.
OR...WINTER WEATHER ADVISORY UNTIL 11 AM MST /10 AM PST/ THIS MORNING
FOR ORZ063.
WINTER WEATHER ADVISORY UNTIL 10 AM PST THIS MORNING FOR ORZ062.
&&
$$
WEATHER.GOV/BOISE
DISCUSSION...VM
AVIATION.....DG
PREV SHORT TERM...GS
PREV LONG TERM....MT/JT
000
FXUS66 KPQR 221639
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
839 AM PST SUN NOV 22 2009
.SYNOPSIS...A STRONG SURFACE LOW OVER WESTERN WASHINGTON THIS MORNING
WILL CONTINUE TO MOVE EAST TODAY AND WEAKEN. HIGH PRES WILL BUILD IN
OVER WESTERN OREGON LATER TODAY AND TONIGHT. A WARM FRONT OFF THE
COAST ON MON WILL LIFT NE TOWARDS NW OREGON AND WESTERN WA....THEN
STALL ON TUE. WED THE FRONT WILL FINALLY LIFT N INTO WA...BEFORE A
COLD FRONT PUSHES SE THROUGH THE REGION THU.
&&
.SHORT TERM...SATELLITE IMAGERY SHOWS THE LOW PRESSURE SYSTEM THAT
CAME ONSHORE OVERNIGHT NEAR WILLAPA BAY IS NOW IN WESTERN WASHINGTON
NEAR 48N 123W. THE ASSOCIATED OCCLUDED FRONT ARCS JUST EAST OF THE
OREGON CASCADES. WINDS OVER THE FORECAST AREA ARE BELOW WARNING
CRITERIA...HOWEVER THERE ARE STILL STRONG WESTERLY WINDS ON THE
BACKSIDE OF THE FRONT WITH WINDS STILL GUSTING IN THE 40S ALONG THE
COAST.
DOPPLER RADAR SHOWING GOOD SHOWER ACTIVITY OVER THE FORECAST AREA
THIS MORNING. CASCADES HAVE ALREADY RECEIVED 8 TO 12 INCHES OF NEW
SNOW OVERNIGHT. STRONG OROGRAPHIC WESTERLY FLOW WILL KEEP SHOWERS
GOING THIS MORNING...AND WILL KEEP THE WINTER STORM WARNING GOING
TODAY. OROGRAPHICS WEAKEN THIS AFTERNOON AS H8 FLOW WEAKENS...SO WE
SHOULD SEE SNOW ACCUMULATIONS DROP OFF CONSIDERABLY THIS AFTERNOON.
POST FRONTAL SHOWERS DROP OFF QUICKLY TONIGHT...LAST ON THE N PART OF
THE CASCADES. AN AREA OF WARM AIR ADVECTION SETS UP OVER THE NW PART
OF THE FORECAST AREA MON...AND CONTINUES INTO TUE. A WEAK SHORTWAVE
MOVES ACROSS THE TOP OF THE DEVELOPING UPPER RIDGE TUE...BRINGING THE
BEST CHANCE FOR OVERRUNNING PRECIPITATION TO THE NW PART OF THE AREA
ON TUE.
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...WEAK HIGH PRES
RIDGE OVER THE FORECAST AREA CONTINUES TO PUSH ENERGY NORTH OF
FORECAST AREA MID WEEK. IT MANAGES TO DELAY THE ARRIVAL OF A SECOND
SYSTEM THROUGH THUR. MODEL SOLUTIONS DIVERGE TOWARD THE END OF THE
WEEK AND HAVE LITTLE CONFIDENCE IN THEM. AT THIS TIME WILL GO WITH
CLIMATOLOGY UNTIL THERE IS SOME CONSISTENCY BETWEEN THE MODELS..
&&
.AVIATION...STRONG FRONT NOW PUSHING INTO EASTERN OREGON...WITH
MOSTLY VFR CONDITIONS. PLENTY OF SHOWERS TO PUSH INLAND THIS
MORNING...WITH OCCASIONAL MVFR. GUSTY SOUTHWEST WINDS WILL EASE
GRADUALLY BETWEEN NOW AND 18Z.
KPDX AND APPROACHES...VFR TODAY...BUT EXPECT OCCASIONAL MVFR CIGS
DOWN TO 2000 FT WITH SHOWERS...ESPECIALLY THIS MORNING. GUSTY SOUTH
TO SOUTHWEST WINDS WILL CONTINUE UNTIL 17Z...THEN GRADUALLY EASE.
WOLFE
&&
.MARINE...WORST IS OVER...BUT STILL A LOT OF GRADIENT ON BACK SIDE
OF THE LOW. WINDS STILL HITTING 40 KT...WILL MAINTAIN SOLID GALES
THROUGH EARLY AFTERNOON. SEAS TOPPING AROUND 22 TO 24 FT THIS
AM...BUT WILL EASE TO THE MID TO LOWER TEENS BY TONIGHT. NEXT SYSTEM
WILL MOVE ACROSS THE COASTAL WATERS ON MON...WITH NEAR GALE FORCE
WINDS. DIFFERENCE IS THAT THE PARENT LOW WILL PASS MUCH FURTHER TO
THE N OF THE AREA. WOLFE
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
WA/OR...GALE WARNING FOR THE COASTAL WATERS FROM CAPE SHOALWATER TO
FLORENCE UNTIL NOON TODAY.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR CONDITIONS
THROUGH SUN NIGHT.
WINTERSTORM WARNING FOR THE S WA AND N AND CENTRAL OREGON
CASCADES TODAY.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS66 KPDT 221141
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
340 AM PST SUN NOV 22 2009
UPDATED AVIATION DISCUSSION
.SHORT TERM...TODAY THROUGH MONDAY...A VIGOROUS STORM SYSTEM
CONTINUES TO MOVE ONSHORE THIS MORNING. THE SURFACE LOW IS NOW OVER
SOUTHWEST WASHINGTON...FAIRLY CLOSE TO THE NAM FORECAST POSITION. A
WARM FRONT...EXTENDING FROM THE TRIPLE POINT NEAR STAMPEDE PASS
SOUTHEAST INTO EAST-CENTRAL OREGON...IS SWINGING NORTHEAST AND EAST.
EXPECT THIS FRONT TO EXIT OUR AREA IN THE NEXT COUPLE OF HOURS.
MEANWHILE THE COLD FRONT HAS STARTED TO JUMP THE CASCADE CREST AND
SHOULD BE THROUGH A GOOD PORTION OF OUR AREA BY DAYBREAK. WILL
CONTINUE ALL CURRENT WARNINGS AND ADVISORIES AS THEY ARE...BUT DID
HAVE TO ADD A SNOW ADVISORY FOR THE CENTRAL OREGON ZONE EARLIER AS
AREAS ABOVE 3500 FEET WERE GETTING A GOOD DUMP OF SNOW. SNOW IS
FALLING AT YAKIMA AND ELLENSBURG. AT THIS TIME IT LOOKS THAT THEY
WILL SEE UP TO 2 INCHES...BUT THE COLD FRONT SHOULD BE THROUGH THESE
TWO LOCATIONS BY 5 AM (POSSIBLY EARLIER). THIS WILL TURN FLOW
WESTERLY AND SIGNIFICANTLY REDUCE PRECIP AND MAY ALSO MIX OUT
TRAPPED COLD AIR AND RAISE THE SNOW LEVELS.
HIGH PRESSURE WILL BUILD INTO THE REGION TONIGHT RESULTING IN WIND
DOWN IN POST SYSTEM SHOWERS. IT WILL ALSO ALLOW FOR SOME CLEARING OF
THE SKIES FOR COOLER OVERNIGHT LOW TEMPS. A WEAK WAVE WILL RIDE OVER
THE UPPER LEVEL HIGH PRESSURE RIDGE OVER THE AREA MONDAY. THIS WAVE
MAY SPREAD SOME LIGHT SNOW OR RAIN INTO THE WASHINGTON CASCADE EAST
SLOPE AREAS. ELSEWHERE CONDITIONS WILL BE DRY. 90
.LONG TERM...MONDAY NIGHT THROUGH NEXT SATURDAY...AN UPPER RIDGE
WILL BEGIN TO BUILD OVER THE PACIFIC NORTHWEST MONDAY NIGHT AND
TUESDAY. THIS WILL CAUSE MOST OF THE MOISTURE WITH ANY WEATHER
SYSTEMS TO BE PUSHED NORTHWARD NORTH OF THE UPPER JET STREAM INTO
FAR NORTHWEST WASHINGTON AND SOUTHWEST CANADA. THIS WILL SPARE THE
FORECAST AREA FROM ANY SIGNIFICANT WEATHER EVENTS THROUGH MOST OF
THE WEEK AS THE UPPER RIDGE STRENGTHENS. HOWEVER WITH THE UPPER
RIDGE DEVELOPING AND THE PRESENCE OF THE RECENT PRECIPITATION PATCHY
VALLEY FOG AND FREEZING FOG WILL DEVELOP OVER THE LOWER COLUMBIA
BASIN AND ADJACENT VALLEYS. IT WILL FORM MAINLY ALONG THE LARGE
RIVERS AND STREAMS AT FIRST AND THEN GRADUALLY EXPAND IN COVERAGE BY
WEDNESDAY AND WILL PERSIST THROUGH THURSDAY. AND PRECIPITATION WILL
BE MAINLY LIGHT RAIN AND SNOW SHOWERS OVER THE MOUNTAINS. A COLD
FRONT WITH A WEATHER SYSTEM WILL APPROACH THE CWA LATE THURSDAY INTO
FRIDAY BRINGING THE NEXT BETTER CHANCE OF PRECIPITATION TO THE
FORECAST AREA BY FRIDAY INTO SATURDAY. TEMPERATURES WILL BE NEAR TO
ABOVE NORMAL IN HIGHER TERRAIN AND NEAR TO BELOW NORMAL IN THE LOWER
TERRAIN THAT IS CAUGHT UNDER TEMPERATURE INVERSIONS AND/OR WITH
FOG/LOW CLOUDS. 88
&&
.AVIATION...12Z TAFS...LIFR TO IFR CONDITIONS WILL PREVAIL AT KRDM
AND KYKM AT TIMES DUE TO SNOW OR A MIX OF RAIN AND SNOW WITH LOW
CEILINGS. A COLD FRONT WILL PASS THESE AREAS ALLOWING PRECIPITATION
TO DECREASE WITH INCREASING CEILINGS...WHICH WILL ALLOW MVFR TO VFR
CONDITIONS TO RETURN FOR MOST OF THE TIME WITH OCCASIONAL PERIODS
OF IFR DUE TO PASSING RAIN AND SHOW SHOWERS. ELSEWHERE MAINLY VFR
CONDITIONS WILL PREVAIL BUT THERE WILL BE PERIODS OF IFR TO MVFR DUE
TO RAIN OR SNOW SHOWERS WITH LOWERED CEILINGS THIS MORNING...WITH
IMPROVING CONDITIONS THIS AFTERNOON. STRONG SOUTH TO EAST WINDS OF
AT LEAST 25 TO 40 KTS WILL BE COMMON EARLY THIS MORNING AT MOST
STATIONS BUT WILL SLOWLY DIMINISH THROUGH THE DAY INTO TONIGHT AND
TURN TO THE SOUTHWEST TO WEST. TONIGHT DECREASING WINDS WITH VFR
CONDITIONS WILL PREVAIL AT ALL LOCATIONS. 88
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 47 32 46 37 / 70 10 10 10
ALW 48 34 47 36 / 80 10 10 20
PSC 53 29 45 35 / 60 10 10 20
YKM 48 23 42 31 / 40 10 10 20
HRI 52 28 45 32 / 60 10 10 10
ELN 44 27 40 27 / 70 10 20 30
RDM 45 20 46 25 / 50 10 10 10
LGD 42 25 40 30 / 80 20 10 10
GCD 42 21 44 25 / 60 10 10 10
DLS 49 33 45 35 / 40 20 10 40
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING UNTIL 10 AM PST THIS MORNING FOR ORZ049-050.
WINTER STORM WARNING UNTIL 7 PM PST THIS EVENING FOR ORZ502.
HIGH WIND WARNING UNTIL 4 PM PST THIS AFTERNOON FOR ORZ042.
WINTER WEATHER ADVISORY UNTIL NOON PST TODAY FOR ORZ043.
WIND ADVISORY UNTIL 1 PM PST THIS AFTERNOON FOR ORZ043.
WIND ADVISORY UNTIL 7 PM PST THIS EVENING FOR ORZ501-504.
WINTER WEATHER ADVISORY UNTIL 7 PM PST THIS EVENING FOR ORZ503.
WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR ORZ041-044.
WA...WINTER WEATHER ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR
WAZ501-502.
WINTER STORM WARNING UNTIL 7 PM PST THIS EVENING FOR WAZ030.
WIND ADVISORY UNTIL 7 PM PST THIS EVENING FOR WAZ029.
WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR WAZ024-028.
&&
THREAT INDEX
TODAY : RED
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
90/88/88
000
FXUS66 KMFR 221111
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
311 AM PST SUN NOV 22 2009
.DISCUSSION...THE STRONG COLD FRONT IS TRAVERSING OUR REGION AS
INDICATED BY THE 00Z GFS. IT IS ABOUT TO REACH THE CASCADES AND
SHOULD MOVE EAST OF LAKE AND MODOC COUNTIES BY AROUND 10 AM.
PRECIPITATION IS LIGHT TO MODERATE WITH SNOW LEVELS AT 3500 TO
4000 FEET. THERE WERE FEW ADJUSTMENTS TO MAKE TO THE FIRST 24
HOURS OF THE FORECAST. THE WIND AND WINTER WEATHER HEADLINE
PRODUCTS ARE EXPECTED TO REMAIN APPROPRIATE THROUGH THEIR
CURRENTLY SCHEDULED EXPIRATIONS...4 AND 7 AM RESPECTIVELY FOR THE
COASTAL AND SHASTA VALLEY WINDS AND 7 AM FOR THE CASCADE AND EAST
SIDE WINTER WEATHER ADVISORY.
SHOWERS WILL BE NUMEROUS BEHIND THE FRONT THEN GRADUALLY TAPER OFF
FROM LATE MORNING INTO THIS EVENING...WITH EVENING CLEARING
LEADING TO A MUCH COLDER NIGHT AND AREAS OF FREEZING FOG.
THE MAIN UPPER LEVEL FEATURE MONDAY THROUGH WEDNESDAY WILL BE A
HIGH PRESSURE RIDGE CENTERED OFFSHORE FROM CENTRAL AND SOUTHERN
CALIFORNIA. A COUPLE OF WEAK TROUGHS WILL RIDE OVER THE TOP OF THE
RIDGE INTO WASHINGTON AND NORTHERN OREGON. THUS...IT WILL BE DRY
ASIDE FROM A SLIGHT CHANCE OF COASTAL SHOWERS NORTH OF CAPE
BLANCO. THE PROXIMITY OF THE TROUGHS WILL ALLOW PERIODS OF SCATTERED
TO BROKEN HIGH CLOUDS. LATE NIGHT AND MORNING FOG WILL BE
PREVALENT IN WEST SIDE VALLEYS.
POPS HAVE BEEN LOWERED FOR WEDNESDAY NIGHT AND ALSO FOR
THANKSGIVING DAY...ESPECIALLY IN AREAS EAST OF THE CASCADES WITH
THE ECMWF AND GFS COMING INTO CLOSER AGREEMENT ON A SLOWER SOLUTION
WITH THE NEXT COLD FRONT. SNOW LEVELS DO NOT LOOK TO BE ESPECIALLY
LOW WITH THE FRONT...AROUND 5000 TO 5500 FEET WHICH IS HIGHER THAN
NORMAL. GIVEN THAT THE MODELS HAVE JUST NOW COME INTO BETTER
AGREEMENT...I WILL KEEP THURSDAY EVENING INTO FRIDAY MORNING POPS IN
THE CHANCE CATEGORY.
BEYOND FRIDAY...THE ECMWF IS STRONGER THAN THE GFS WITH A RIDGE
BUILDING OVER THE OFFSHORE WATERS. THUS...THE ECMWF SOLUTION FOR
FRIDAY NIGHT THROUGH THE WEEKEND WOULD BE COLDER BUT DRIER. I WILL
CONTINUE WITH A COMPROMISE BETWEEN THE TWO MODELS FOR THE LATTER
PART OF THE FORECAST PERIOD. ANY LIGHT SHOWERS DEPICTED BY THE
GFS WOULD BE MAINLY FROM THE CASCADES WESTWARD.
&&
.AVIATION...A STRONG COLD FRONT JUST WEST OF THE CASCADES WILL
CONTINUE TO MOVE EAST AND EXIT OUR REGION AROUND 10 AM THIS MORNING.
THE FRONT HAS LIGHT TO MODERATE PRECIPITATION WITH MOUNTAIN
OBSCURATIONS...STRONG SOUTHERLY WINDS AND AREAS OF MVFR CEILINGS.
POST-FRONTAL SHOWERS WILL GRADUALLY DECREASE THIS AFTERNOON INTO
THIS EVENING WITH VFR BECOMING THE PREVAILING CONDITION. VALLEY FOG
WILL DEVELOP LATE TONIGHT INTO MONDAY MORNING WEST OF THE CASCADES WITH
AREAS OF IFR CONDITIONS.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 7 AM PST THIS MORNING FOR ORZ027-
ORZ028-ORZ029-ORZ030.
WIND ADVISORY UNTIL 7 AM PST THIS MORNING FOR ORZ031.
HIGH WIND WARNING UNTIL 4 AM PST EARLY THIS MORNING FOR ORZ021-
ORZ022.
CA...WIND ADVISORY UNTIL 4 AM PST EARLY THIS MORNING FOR CAZ081.
PACIFIC COASTAL WATERS...STORM WARNING UNTIL 4 AM PST EARLY THIS
MORNING FOR PZZ350-PZZ370.
HAZARDOUS SEAS WARNING UNTIL 4 AM PST MONDAY FOR PZZ350-PZZ356-
PZZ370-PZZ376.
GALE WARNING UNTIL 4 AM PST EARLY THIS MORNING FOR PZZ356-PZZ376.
$$
DW
000
FXUS66 KPDT 221059
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
259 AM PST SUN NOV 22 2009
.SHORT TERM...TODAY THROUGH MONDAY...A VIGOROUS STORM SYSTEM
CONTINUES TO MOVE ONSHORE THIS MORNING. THE SURFACE LOW IS NOW OVER
SOUTHWEST WASHINGTON...FAIRLY CLOSE TO THE NAM FORECAST POSITION. A
WARM FRONT...EXTENDING FROM THE TRIPLE POINT NEAR STAMPEDE PASS
SOUTHEAST INTO EAST-CENTRAL OREGON...IS SWINGING NORTHEAST AND EAST.
EXPECT THIS FRONT TO EXIT OUR AREA IN THE NEXT COUPLE OF HOURS.
MEANWHILE THE COLD FRONT HAS STARTED TO JUMP THE CASCADE CREST AND
SHOULD BE THROUGH A GOOD PORTION OF OUR AREA BY DAYBREAK. WILL
CONTINUE ALL CURRENT WARNINGS AND ADVISORIES AS THEY ARE...BUT DID
HAVE TO ADD A SNOW ADVISORY FOR THE CENTRAL OREGON ZONE EARLIER AS
AREAS ABOVE 3500 FEET WERE GETTING A GOOD DUMP OF SNOW. SNOW IS
FALLING AT YAKIMA AND ELLENSBURG. AT THIS TIME IT LOOKS THAT THEY
WILL SEE UP TO 2 INCHES...BUT THE COLD FRONT SHOULD BE THROUGH THESE
TWO LOCATIONS BY 5 AM (POSSIBLY EARLIER). THIS WILL TURN FLOW
WESTERLY AND SIGNIFICANTLY REDUCE PRECIP AND MAY ALSO MIX OUT
TRAPPED COLD AIR AND RAISE THE SNOW LEVELS.
HIGH PRESSURE WILL BUILD INTO THE REGION TONIGHT RESULTING IN WIND
DOWN IN POST SYSTEM SHOWERS. IT WILL ALSO ALLOW FOR SOME CLEARING OF
THE SKIES FOR COOLER OVERNIGHT LOW TEMPS. A WEAK WAVE WILL RIDE OVER
THE UPPER LEVEL HIGH PRESSURE RIDGE OVER THE AREA MONDAY. THIS WAVE
MAY SPREAD SOME LIGHT SNOW OR RAIN INTO THE WASHINGTON CASCADE EAST
SLOPE AREAS. ELSEWHERE CONDITIONS WILL BE DRY. 90
.LONG TERM...MONDAY NIGHT THROUGH NEXT SATURDAY...AN UPPER RIDGE
WILL BEGIN TO BUILD OVER THE PACIFIC NORTHWEST MONDAY NIGHT AND
TUESDAY. THIS WILL CAUSE MOST OF THE MOISTURE WITH ANY WEATHER
SYSTEMS TO BE PUSHED NORTHWARD NORTH OF THE UPPER JET STREAM INTO
FAR NORTHWEST WASHINGTON AND SOUTHWEST CANADA. THIS WILL SPARE THE
FORECAST AREA FROM ANY SIGNIFICANT WEATHER EVENTS THROUGH MOST OF
THE WEEK AS THE UPPER RIDGE STRENGTHENS. HOWEVER WITH THE UPPER
RIDGE DEVELOPING AND THE PRESENCE OF THE RECENT PRECIPITATION PATCHY
VALLEY FOG AND FREEZING FOG WILL DEVELOP OVER THE LOWER COLUMBIA
BASIN AND ADJACENT VALLEYS. IT WILL FORM MAINLY ALONG THE LARGE
RIVERS AND STREAMS AT FIRST AND THEN GRADUALLY EXPAND IN COVERAGE BY
WEDNESDAY AND WILL PERSIST THROUGH THURSDAY. AND PRECIPITATION WILL
BE MAINLY LIGHT RAIN AND SNOW SHOWERS OVER THE MOUNTAINS. A COLD
FRONT WITH A WEATHER SYSTEM WILL APPROACH THE CWA LATE THURSDAY INTO
FRIDAY BRINGING THE NEXT BETTER CHANCE OF PRECIPITATION TO THE
FORECAST AREA BY FRIDAY INTO SATURDAY. TEMPERATURES WILL BE NEAR TO
ABOVE NORMAL IN HIGHER TERRAIN AND NEAR TO BELOW NORMAL IN THE LOWER
TERRAIN THAT IS CAUGHT UNDER TEMPERATURE INVERSIONS AND/OR WITH
FOG/LOW CLOUDS. 88
&&
.AVIATION...PREVIOUS DISCUSSION...06Z TAFS...A PACIFIC WEATHER
SYSTEM WILL MOVE THROUGH THE AREA BRINGING RAIN AND SNOW LATER
TONIGHT AND TOMORROW MORNING BEFORE TAPERING OFF IN THE AFTERNOON.
VFR CONDITIONS WITH BROKEN MID AND HIGH CLOUDS ARE EXPECTED THROUGH
22/09Z THEN AS THE RAIN AND SNOW MOVES IN...MVFR CEILINGS ARE
EXPECTED TO DEVELOP IN AND NEAR THE CASCADES AND IN THE EASTERN
MOUNTAINS AFFECTING KDLS...KRDM AND KYKM AT TIMES THROUGH 22/20Z.
MVFR VISIBILITIES ARE POSSIBLE NEAR THE HEAVIER SNOW SHOWERS AT KYKM
AND KRDM. KPSC...KPDT AND KALW WILL GENERALLY STAY AT LOW VFR
CEILINGS THOUGH STRONGER SHOWERS COULD HAVE BRIEF PERIODS OF MVFR
CEILINGS. CONDITIONS WILL IMPROVE TO VFR LEVELS AT ALL TAF LOCATIONS
AFTER 22/20Z. WINDS AT KDLS...KRDM...KYKM AND KPSC WILL INCREASE
LATER TONIGHT TO 10 TO 20 KTS WITH GUSTS TO 30 KTS AT ALL TAF
LOCATIONS THROUGH 23/00Z THEN DECREASE TO BELOW 15 KTS AFTER THAT.
KPDT AND KALW WILL SEE 10 TO 20 KTS WITH GUSTS TO 30 KTS THROUGH
22/12Z...INCREASE TO 15 TO 25 KTS WITH GUSTS TO 40 KTS THROUGH
23/02Z THE DECREASE BACK TO 10 TO 20 KTS WITH GUSTS TO 25 KTS AFTER
THAT.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 47 32 46 37 / 70 10 10 10
ALW 48 34 47 36 / 80 10 10 20
PSC 53 29 45 35 / 60 10 10 20
YKM 48 23 42 31 / 40 10 10 20
HRI 52 28 45 32 / 60 10 10 10
ELN 44 27 40 27 / 70 10 20 30
RDM 45 20 46 25 / 50 10 10 10
LGD 42 25 40 30 / 80 20 10 10
GCD 42 21 44 25 / 60 10 10 10
DLS 49 33 45 35 / 40 20 10 40
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING UNTIL 10 AM PST THIS MORNING FOR ORZ049-050.
WINTER STORM WARNING UNTIL 7 PM PST THIS EVENING FOR ORZ502.
HIGH WIND WARNING UNTIL 4 PM PST THIS AFTERNOON FOR ORZ042.
WINTER WEATHER ADVISORY UNTIL NOON PST TODAY FOR ORZ043.
WIND ADVISORY UNTIL 1 PM PST THIS AFTERNOON FOR ORZ043.
WIND ADVISORY UNTIL 7 PM PST THIS EVENING FOR ORZ501-504.
WINTER WEATHER ADVISORY UNTIL 7 PM PST THIS EVENING FOR ORZ503.
WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR ORZ041-044.
WA...WINTER WEATHER ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR WAZ501-
502.
WINTER STORM WARNING UNTIL 7 PM PST THIS EVENING FOR WAZ030.
WIND ADVISORY UNTIL 7 PM PST THIS EVENING FOR WAZ029.
WIND ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR WAZ024-028.
&&
THREAT INDEX
TODAY : RED
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
90/88/88
000
FXUS65 KBOI 221039
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
340 AM MST SUN NOV 22 2009
.SHORT TERM...VIGOROUS STORM SYSTEM CURRENTLY PUSHING INTO THE
FORECAST AREA WITH SNOW AND WIND. SYSTEM IS FAST MOVING EMBEDDED
WITHIN 120-140 KNOT JETSTREAM CORE...THUS MAIN IMPACTS NOT EXPECTED
TO LAST MORE THAN A FEW HOURS OVER ANY ONE AREA TODAY. HAVE ADDED
HARNEY AND MALHEUR COUNTIES IN OREGON TO THE WINTER WEATHER
ADVISORIES WITH LIGHT TO MODERATE SNOW AND INCREASING WINDS.
SYNOPTICALLY...A WARM FRONT IS MOVING THROUGH SOUTHEAST OREGON WITH
A COLD FRONT ALIGNED NORTH SOUTH JUST EAST OF THE CASCADES. SYSTEM
EXPECTED TO OCCLUDE LATER THIS AFTERNOON OVER OUR AREA AND WEAKEN.
NEVERTHELESS...SEVERAL INCHES OF NEW SNOW CAN BE EXPECTED IN THE
NORTHERN MOUNTAINS WITH 1 TO 3 INCHES IN VALLEYS SOUTH TO THE SNAKE
RIVER. LESS SNOW IS FORECAST SOUTHWARD TOWARD THE NEVADA STATE LINE.
DUE TO THE QUICK MOVEMENT TO THE SYSTEM...HEAVY PRECIP IS NOT
EXPECTED TO LAST FOR A LONG TIME BUT INCREASING WINDS WITH BLOWING
SNOW WILL BE JUST AS IMPORTANT AN IMPACT AS THE ACTUAL SNOW FALL.
TREASURE AND MAGIC VALLEYS A LITTLE MORE TRICKY WITH SOUNDING
PROFILES INDICATING LIGHT SNOW EARLY THIS MORNING FOLLOWED BY A
MIXTURE...THEN TO ALL RAIN BY THIS AFTERNOON AS WINDS TURN WESTERLY
BEHIND FRONT...ALTHOUGH NOT EXPECTING SIGNIFICANT SNOW
ACCUMULATIONS. LINGERING SNOW SHOWERS TO REMAIN TONIGHT IN THE UPPER
TROF AXIS WITH DRIER CONDITIONS ANTICIPATED FOR MONDAY AS YET
ANOTHER RIDGE BUILDS OVER THE AREA.
.LONG TERM..MONDAY NIGHT THROUGH SUNDAY...DRY CONDITIONS MONDAY
THROUGH THURSDAY AS AN UPPER LEVEL RIDGE AMPLIFIES OVER NRN
CALIFORNIA/NEVADA. THUS...STRENGTH OF SURFACE INVERSION CONTINUES TO
BE THE MAIN FORECAST CHALLENGE. MODEL SOUNDINGS INDICATE SOME MIXING
TUESDAY AFTERNOON...NOT UNTIL WEDNESDAY DOES INVERSION LOOK TO REACH
ITS FULL POTENTIAL. EXPECT BELOW NORMAL VALLEY TEMPERATURES /ABOVE
NORMAL TEMPS IN MTN VALLEYS/ AND FOG ON WEDNESDAY...AND POSSIBLY
EVEN THURSDAY. MODELS IN BETTER AGREEMENT WITH AN UPPER LEVEL TROUGH
PROGGED TO MOVE INTO THE FORECAST AREA EARLY FRIDAY. EXPECT CHANCES
FOR VALLEY RAIN/SNOW AND MOUNTAIN SNOW ON FRIDAY...THEN DRIER ON
SATURDAY AND SUNDAY AS SYSTEM QUICKLY EXITS THE FORECAST AREA.
&&
.AVIATION...WIDESPREAD IFR CONDITIONS IN SNOW /ALL AREAS/ THROUGH
20Z. AFTER 20Z...SHOWERS WILL SLOWLY TAPER OFF ACROSS SE OREGON BUT
PERSIST ACROSS SW ID. STILL EXPECTING SEVERAL HOURS OF IFR
CONDITIONS AT KBOI LATE SUNDAY MORNING...GENERALLY 14Z-19Z. MODERATE
SE SURFACE WINDS WITH LOCALIZED GUSTS TO 35 KTS...WILL BECOME
MODERATE WESTERLY THIS AFTERNOON. STRONG /40-50 KTS/ WESTERLY WINDS
ALOFT.
OUTLOOK...DEVELOPMENT OF INVERSION NEXT WEEK WILL BRING CHANCE OF
IFR CONDITIONS IN FOG/STRATUS TO TREASURE/BAKER/WEISER VALLEYS ON
WEDNESDAY.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...WINTER WEATHER ADVISORY FROM 4 AM TO 2 PM MST SUNDAY FOR IDZ033.
WINTER WEATHER ADVISORY FROM 4 AM TO 2 PM MST SUNDAY FOR IDZ011-
IDZ013.
OR...WINTER WEATHER ADVISORY FROM 1 AM TO 10 AM PST SUNDAY FOR
ORZ061-ORZ62-ORZ63.
&&
$$
WEATHER.GOV/BOISE
SHORT TERM...GS
LONG TERM....MT/JT
AVIATION.....MT
000
FXUS66 KPQR 221030
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
230 AM PST SUN NOV 22 2009
.SYNOPSIS...A STRONG SURFACE LOW OVER SW WA THIS MORNING WILL
CONTINUE TO MOVE E TODAY AND WEAKEN. HIGH PRES WILL BUILD IN OVER
WESTERN OREGON LATER TODAY AND TONIGHT. A WARM FRONT OFF THE COAST
ON MON WILL LIFT NE TOWARDS NW OREGON AND WESTERN WA....THEN STALL
ON TUE. WED THE FRONT WILL FINALLY LIFT N INTO WA...BEFORE A COLD
FRONT PUSHES SE THROUGH THE REGION THU.
&&
.SHORT TERM...SURFACE LOW PASSED JUST N OF BUOY 46089 A FEW HOURS
AGO...APPARENTLY MOVING ENE HEADED TOWARDS ROUGHLY WILLAPA BAY. COLD
FRONT HAS PUSHED E INTO THE CENTRAL OREGON COAST WITH PEAK GUSTS
AROUND 80 MPH. BUOYS INDICATE AN IMPRESSIVE WIND FIELD IN THE POST
FRONTAL WESTERLY FLOW...WITH STORM FORCE GUSTS CONTINUING THROUGH
09Z AT 46089 AND 46050. BASED ON E WINDS ALONG THE N OREGON
COAST...FRONT APPEARS TO BE OCCLUDED N OF KTMK...SO ANY HIGH WINDS N
OF THERE WILL NEED TO COME OUT OF THE SW BEHIND THE FRONT. STRONG
PRESSURE RISES BEHIND THE COLD FRONT HAVE MAINTAINED HIGH WINDS FOR
A COUPLE HOURS BEHIND THE FRONT. WITH THE STRONG PRESSURE RISES
BEHIND THE FRONT...WILL LIKELY NEED TO HANG ONTO THE INLAND WIND
ADVISORY EARLY THIS MORNING. ELSEWHERE EXPECT BE ABLE TO DROP THE
HIGH WIND WARNINGS WITH THE NEXT FORECAST PACKAGE.
SNOW INTENSITY PICKED UP IN THE CASCADES AFTER ROUGHLY 10 PM AS
HEAVIER BANDS OF PRECIPITATION LIFTED UP. SATELLITE AND RADAR
SUGGEST AT LEAST ONE MORE BAND OF ENHANCED PRECIPITATION YET EARLY
THIS MORNING...BEFORE THE STRONG OROGRAPHIC WESTERLY FLOW KICKS IN
BEHIND THE FRONT. OROGRAPHICS WEAKEN IN THE AFTERNOON AS H8 FLOW
WEAKENS...SO WE SHOULD SEE SNOW ACCUMULATIONS DROP OFF CONSIDERABLY
IN THE AFTERNOON.
POST FRONTAL SHOWERS DROP OFF QUICKLY TONIGHT...LAST ON THE N PART
OF THE CASCADES. AN AREA OF WARM AIR ADVECTION SETS UP OVER THE NW
PART OF THE FORECAST AREA MON...AND CONTINUES INTO TUE. A WEAK
SHORTWAVE MOVES ACROSS THE TOP OF THE DEVELOPING UPPER RIDGE
TUE...BRINGING THE BEST CHANCE FOR OVERRUNNING PRECIPITATION TO THE
NW PART OF THE AREA ON TUE.
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
WEAK HIGH PRES RIDGE OVER THE FORECAST AREA CONTINUES TO PUSH ENERGY
NORTH OF FORECAST AREA MID WEEK. IT MANAGES TO DELAY THE ARRIVAL OF
A SECOND SYSTEM THROUGH THUR. MODEL SOLUTIONS DIVERGE TOWARD THE END
OF THE WEEK AND HAVE LITTLE CONFIDENCE IN THEM. AT THIS TIME WILL GO
WITH CLIMATOLOGY UNTIL THERE IS SOME CONSISTENCY BETWEEN THE MODELS..
&&
.AVIATION...STRONG FRONT NOW PUSHING ACROSS THE REGION...WITH MOSTLY
VFR CONDITIONS. PLENTY OF SHOWERS TO PUSH INLAND THIS MORNING...WITH
OCCASIONAL MVFR. MAIN STORY IS THE GUSTY SOUTH TO SOUTHWEST WINDS
OVER REGION. WINDS WILL EASE GRADUALLY BETWEEN 14Z AND 18Z.
KPDX AND APPROACHES...VFR TODAY...BUT EXPECT OCCASIONAL MVFR CIGS
DOWN TO 2000 FT WITH SHOWERS...ESPECIALLY AFTER 14Z. GUSTY SOUTH TO
SOUTHWEST WINDS WILL CONTINUE UNTIL 17Z...THEN GRADUALLY EASE.
&&
.MARINE...WORST IS OVER...BUT STILL A LOT OF GRADIENT ON BACK SIDE
OF THE LOW. WITH WINDS STILL HITTING 45 TO 50 KT...WILL MAINTAIN
STORM WARNING UNTIL 7 AM. THEN SOLID GALES AFTERWARDS. SEAS TOPPING
AROUND 22 TO 24 FT THIS AM...BUT LIKE THE WIND THESE TOO SHALL EASE
TODAY. NEXT SYSTEM WILL MOVE ACROSS THE COASTAL WATERS ON MON...WITH
NEAR GALE FORCE WIND. DIFFERENCE IS THAT THE PARENT LOW WILL PASS
MUCH FURTHER TO THE N OF THE AREA. &&
.PQR WATCHES/WARNINGS/ADVISORIES...
WA/OR...STORM WARNING FOR THE COASTAL WATERS FROM CAPE SHOALWATER TO
FLORENCE UNTIL 7 AM THIS MORNING.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR CONDITIONS
THROUGH SUN NIGHT.
WINTER STORM WARNING FOR THE S WA AND N AND CENTRAL OREGON
CASCADES TODAY.
WIND ADVISORY FOR THE WILLAMETTE VALLEY...THE LOWER
COLUMBIA...AND THE I-5 CORRIDOR FOR THIS EVENING THROUGH
7 AM.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS66 KPDT 220600 AAA
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
1000 PM PST SAT NOV 21 2009
UPDATED AVIATION DISCUSSION.
.UPDATE...A DEVELOPING FRONT IS APPROACHING THE PACIFIC NORTHWEST
COAST AND WILL COME ASHORE BEFORE MIDNIGHT. RADAR ON THE WEST SIDE
OF THE CASCADES IS SHOWING SUBSTANTIAL RETURNS AND LIGHT RAIN HAS
BEEN FALLING IN PORTLAND AND SEATTLE FOR A COUPLE OF HOURS. STAMPEDE
PASS IS REPORTING MODERATE SNOW AT THIS TIME BUT AM NOT SEEING SNOW
ON ANY OF THE WEB CAMS IN THE CASCADE PASSES. EXPECT THAT
PRECIPITATION WILL BEGIN IN THE NEXT HOUR OR TWO NEAR THE CASCADE
CREST AND WORK ITS WAY ACROSS THE AREA OVERNIGHT. WINDS HAVE BEEN
LIGHT BUT RADAR VELOCITY RETURNS ARE INCREASING ON BOTH LOCAL AND
PORTLAND AND SEATTLE RADARS SHOWING THAT STRONGER WINDS WILL BE
PRESENT ALOFT BEFORE LONG. WIND PROFILER DATA SHOWS AN INCREASING
TREND AS WELL. WATER VAPOR LOOP SHOWS AN AREA OF DARKENING BEHIND
THE FRONT THAT IS INCREASING IN SIZE AND STRENGTH AS THE FRONT
DEVELOPS. ALTHOUGH WINDS WILL TAKE A FEW HOURS TO TAKE OFF...WILL
LEAVE WIND GRIDS AS IS THOUGH STRONG WINDS MAY BE SPOTTY IN COVERAGE
AT FIRST. LATEST OBSERVATIONS ARE STARTING TO SHOW SOME 15 TO 25 MPH
WINDS SO WIND FORECAST...ADVISORIES AND WARNINGS LOOK GOOD.
TEMPERATURES ARE IN MANY CASES NOT TOO FAR FROM FORECAST OVERNIGHT
LOW TEMPERATURES WHICH IS A BIT CONCERNING BUT AS SOUTH WINDS
INCREASE...TEMPERATURES SHOULD INCREASE SO WILL LEAVE FORECAST AS
IS. OVERALL...FORECAST IS IN GOOD SHAPE. NO UPDATE PLANNED. PERRY
&&
.AVIATION...06Z TAFS...A PACIFIC WEATHER SYSTEM WILL MOVE THROUGH
THE AREA BRINGING RAIN AND SNOW LATER TONIGHT AND TOMORROW MORNING
BEFORE TAPERING OFF IN THE AFTERNOON. VFR CONDITIONS WITH BROKEN MID
AND HIGH CLOUDS ARE EXPECTED THROUGH 22/09Z THEN AS THE RAIN AND
SNOW MOVES IN...MVFR CEILINGS ARE EXPECTED TO DEVELOP IN AND NEAR
THE CASCADES AND IN THE EASTERN MOUNTAINS AFFECTING KDLS...KRDM AND
KYKM AT TIMES THROUGH 22/20Z. MVFR VISIBILITIES ARE POSSIBLE NEAR
THE HEAVIER SNOW SHOWERS AT KYKM AND KRDM. KPSC...KPDT AND KALW WILL
GENERALLY STAY AT LOW VFR CEILINGS THOUGH STRONGER SHOWERS COULD
HAVE BRIEF PERIODS OF MVFR CEILINGS. CONDITIONS WILL IMPROVE TO VFR
LEVELS AT ALL TAF LOCATIONS AFTER 22/20Z. WINDS AT
KDLS...KRDM...KYKM AND KPSC WILL INCREASE LATER TONIGHT TO 10 TO 20
KTS WITH GUSTS TO 30 KTS AT ALL TAF LOCATIONS THROUGH 23/00Z THEN
DECREASE TO BELOW 15 KTS AFTER THAT. KPDT AND KALW WILL SEE 10 TO 20
KTS WITH GUSTS TO 30 KTS THROUGH 22/12Z...INCREASE TO 15 TO 25 KTS
WITH GUSTS TO 40 KTS THROUGH 23/02Z THE DECREASE BACK TO 10 TO 20
KTS WITH GUSTS TO 25 KTS AFTER THAT. PERRY
&&
.PREV DISCUSSION... /ISSUED 332 PM PST SAT NOV 21 2009/
SHORT TERM...TONIGHT THROUGH MONDAY...THOUGHTS HAVE CHANGED LITTLE
FROM THE PREVIOUS OVERNIGHT SHIFT. MODELS REMAINED VERY CONSISTENT
WITH THE PROGRESSION OF THE SYSTEM ACROSS THE AREA. WITH A COUPLE OF
PRONOUNCED ISSUES DEALT WITH TODAY.
FIRST, DECIDED TO FOLLOW THE SURFACE LOW AS SHOWN BY THE NAM WITH
THE 18Z GFS NOW LENDING THE CLOSEST SUPPORT OF RECENT RUNS. THIS
GIVES A VERY TIGHT PRESSURE GRADIENT ACROSS MOST OF THE AREA AS THE
SURFACE LOW TRACKS ACROSS THE WASHINGTON CASCADES AND THE LOWER
COLUMBIA BASIN BEFORE LIFTING NORTHEAST LATER TOMORROW. THESE
GRADIENTS, COMBINED WITH A VERY STABLE LOWER LEVEL AIR MASS, WILL
GIVE A PROLONGED PERIOD OF STRONG WINDS ALOFT DOWN TOWARD THE
SURFACE. WILL ISSUE NUMEROUS WIND ADVISORIES AND HIGH WIND WARNINGS
AS A RESULT.
THE SECOND ISSUE DEALS WITH SNOWFALL. SNOW LEVEL WILL BE SOMEWHAT
VARIABLE WITH A BRIEF PERIOD OF WARM AIR ADVECTION AS WARM DIFFLUENT
AIR CROSSES THE CASCADES TONIGHT. THE WASHINGTON CASCADES WILL SEE
SIGNIFICANT ACCUMULATIONS MAINLY TONIGHT WITH THE MAJOR PASSES
IMPACTED. DO THINK MAINLY WESTERN AREAS WILL BEAR THE BRUNT AFTER
THE COLD FRONT PASSES LATER TONIGHT AND SUNDAY. THE BLUE MOUNTAINS
WILL START SEEING ACCUMULATIONS LATER TONIGHT AT THE HIGHER
ELEVATIONS AND PASSES BUT SNOW LEVELS WILL DROP AND ACCUMULATION
RATES WILL INCREASE MAINLY TOMORROW AFTER THE COLD FRONT PASSES AND
A NORTHWESTERLY FLOW DEVELOPS. BOTH AREAS WILL SEE SIGNIFICANT
BLOWING SNOW BUT DONT HAVE THE CONFIDENCE TO GO WITH A BLIZZARD
WARNING, BUT IT BEARS WATCHING HOWEVER.
OTHER MOUNTAIN AREAS WILL SEE SNOW AND MAYBE SOME BLOWING AS WELL,
BUT SHOULD STAY BELOW ADVISORY AMOUNTS. PRECIPITATION SHOULD BEGIN
TAPERING OFF ACROSS THE WEST BY TOMORROW AFTERNOON AND GRADUALLY
TAPER OFF ACROSS THE EAST TOMORROW EVENING. /JBONK
LONG TERM...MONDAY NIGHT THROUGH SATURDAY...A WEAK SYSTEM WILL
BREAK UP MONDAY NIGHT IT RIDES OVER A BUILDING UPPER LEVEL RIDGE.
THE BUILDING RIDGE WILL MOVE SLOWLY EAST OVER THE PACIFIC NORTHWEST
TUESDAY. THE DEPARTING SYSTEM WILL COMBINE WILL UPSLOPE FLOW IN THE
MOUNTAINS TO KEEP A SLIGHT CHANCE OF SHOWERS IN NORTHEAST OREGON
TUESDAY. ALSO...SLOPOVER PRECIPITATION MAY OCCUR NEAR THE CASCADES.
SUBSIDENCE ASSOCIATED WITH THE RIDGE WILL PROVIDE LIGHT WINDS AND
CLEARING SKIES WITH THE STRONG SURFACE INVERSIONS TUESDAY NIGHT. IN
THE LOWER COLUMBIA BASIN PATCHY FOG AND FREEZING FOG WILL FORM AT
NIGHT UNDER THE INVERSIONS AND KEEP DAYTIME TEMPERATURES WEDNESDAY
BELOW NORMAL. AT HIGHER ELEVATIONS THE SURFACE INVERSIONS WILL BREAK
DURING THE DAY AND WARMER AIR ALOFT ASSOCIATED WITH THE RIDGE WILL
REACH THE SURFACE TO PRODUCE LARGE DIURNAL TEMPERATURE SPREADS.
WEDNESDAY NIGHT THROUGH FRIDAY THERE ARE DRAMATIC DIFFERENCES
BETWEEN THE GFS AND ECMWF MODELS EVEN THOUGH BOTH HAVE SOUTHWEST
FLOW AT 500 MB. THE 0Z ECMWF HAS A MORE PROGRESSIVE PATTERN WITH A
FRONT AT AN ANGLE TO THE 500 MB FLOW THAT WILL MOVE INTO EASTERN
WASHINGTON AND OREGON AND FORM A DEFORMATION ZONE OVER THE BLUE
MOUNTAINS THAT DROPS HALF AN INCH OF RAIN THURSDAY. THE 12Z GFS HAS
THE FRONT PARALLEL TO THE 500 MB FLOW SO IT REMAINS OFFSHORE UNTIL
FRIDAY. THE GFS ENSEMBLE RUNS SHOW 500 MB FLOW RUNNING TO BOTH
EXTREMES WITH NO CLUSTERING. DECIDED TO MAKE LITTLE CHANGE TO
EXISTING FORECAST WITH A CHANCE OF POPS MOST PLACES AND LIKELY POPS
OVER THE MOUNTAINS. THINK ECMWF IS OVERBLOWN WITH AMOUNT OF
PRECIPITATION UNLESS THE DEFORMATION BAND DOES SET UP...BUT DID
TREND TOWARD IT BY KEEPING AT LEAST A CHANCE OF POPS ACROSS THE
AREA. WHEN THE 12Z RUN OF THE ECMWF ARRIVED IT WAS SLOWER WITH NO
DEFORMATION BAND...BUT IT STILL SUPPORTED THE FASTER ARRIVAL OF THE
FRONT DURING THE DAY THURSDAY. BOTH MODELS HAD PRECIPITATION FRIDAY
WITH THE GFS PUSHING THE FRONT THROUGH AND THE ECMWF MOVING THE
UPPER LEVEL TROUGH THROUGH. WITH LOW CONFIDENCE DUE TO MODEL
DIFFERENCES KEPT A LOW CHANCE POPS ACROSS THE AREA SATURDAY.
COONFIELD
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 41 47 31 43 / 80 70 10 10
ALW 39 48 32 43 / 90 80 10 10
PSC 37 51 30 44 / 90 50 10 10
YKM 32 45 29 44 / 90 40 10 10
HRI 38 49 29 45 / 80 50 10 10
ELN 34 39 26 39 / 90 70 10 20
RDM 35 45 24 47 / 80 40 10 10
LGD 36 42 23 40 / 80 80 20 10
GCD 34 41 21 44 / 70 60 10 10
DLS 37 49 32 47 / 80 40 20 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING UNTIL 10 AM PST SUNDAY FOR ORZ049-050.
WINTER STORM WARNING UNTIL 7 PM PST SUNDAY FOR ORZ502.
HIGH WIND WARNING FROM 1 AM TO 4 PM PST SUNDAY FOR ORZ042.
WIND ADVISORY UNTIL 1 PM PST SUNDAY FOR ORZ043.
WIND ADVISORY UNTIL 7 PM PST SUNDAY FOR ORZ501-504.
WINTER WEATHER ADVISORY UNTIL 7 PM PST SUNDAY FOR ORZ503.
WIND ADVISORY FROM 4 AM TO 4 PM PST SUNDAY FOR ORZ041-044.
WA...WINTER WEATHER ADVISORY UNTIL 4 PM PST SUNDAY FOR WAZ501-502.
WINTER STORM WARNING UNTIL 7 PM PST SUNDAY FOR WAZ030.
WIND ADVISORY UNTIL 7 PM PST SUNDAY FOR WAZ029.
WIND ADVISORY FROM 4 AM TO 4 PM PST SUNDAY FOR WAZ024-028.
&&
THREAT INDEX
SUNDAY : RED
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
83/76/83
000
FXUS66 KMFR 220548
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
902 PM PST SAT NOV 21 2009
.DISCUSSION...TIGHT...RAPIDLY DEVELOPING DEEP SURFACE LOW MOVING
QUICKLY TOWARD THE NORTHERN OREGON COAST. NAM POSITION SLIGHTLY
TOO FAR NORTH AND EAST. EXPECT THE TRACK TO BE SOUTH OF NAM
FORECAST POSITION. CURRENT FORECASTS TAKE THIS INTO ACCOUNT AND
LOOK GOOD. STORM FORCE WINDS ALREADY IN THE OUTER WATERS NORTH
OF THE CAPE AND WINDS SHOULD COME UP RAPIDLY IN THE NEXT 3 HOURS
ALONG THE COAST. PROGS SHOW THE WEATHER SETTLING DOWN SUNDAY AND
MONDAY...THEN HIGH PRESSURE DOMINATING UNTIL THE END OF NEXT WEEK.
NO UPDATES NEEDED THIS EVENING.
&&
.AVIATION...CURRENT VFR CEILINGS WILL BE SHORT-LIVED AS THE
OFFSHORE FRONT DROPS CEILING TO MVFR IN LOW CLOUDS AND SHOWERS IN
THE NEXT FEW HOURS. COASTAL TERMINALS WILL LIKELY BE IMPACTED BY
LOW LEVEL WIND SHEAR WITH GUSTY WINDS TO 35KT BUT EVEN STRONGER
50-60KT WINDS JUST ABOVE THE SURFACE. STRONG WINDS WILL ALSO
IMPACT THE CASCADES AND THE EAST SIDE LATE TONIGHT AND SUNDAY
MORNING. MOUNTAINS AND EAST SIDE WILL HAVE SNOW LATE TONIGHT AND
SUNDAY MORNING...REDUCING VISIBILITIES. MOUNTAIN OBSCURATION WILL
BE WIDESPREAD BY TONIGHT THROUGH SUNDAY AS DEEP MOISTURE PUSHES
INTO THE REGION.
&&
.PREV DISCUSSION... /ISSUED 301 PM PST SAT NOV 21 2009/
DISCUSSION...QUICK-MOVING DEVELOPING FRONTAL SYSTEM WILL IMPACT
THE CWA TONIGHT THROUGH SUNDAY MORNING. THE MAIN IMPACTS WILL BE
STRONG WINDS AND SOME SNOW OVER THE CASCADES AND THE EAST SIDE.
THE FAST MOVEMENT OF THIS SYSTEM...ALONG WITH MORE WESTERLY
WINDS...WILL FAVOR THE CASCADES RECEIVING MORE SNOWFALL AND THE
MOUNT SHASTA AREA RECEIVING LESS THAN THE PREVIOUS STORM. MODELS
HAVE SETTLED ON A 990MB LOW CENTERED WEST OF THE WA/OR BORDER LATE
TONIGHT. THE STRONGEST WINDS WILL IMPACT COASTAL WATERS AND
COASTAL ZONES TONIGHT...WITH WINDS AFFECTING THE CASCADES THROUGH
THE EAST SIDE LATE TONIGHT THROUGH SUNDAY MORNING. VERY STRONG H8
FLOW OF 50KT IS NOTED OVER NORTHWESTERN PORTION OF THE CWA LATE
TONIGHT...BUT STABILITY SHOULD KEEP MOST OF THIS AREA FROM GETTING
ADVISORY LEVEL WINDS. THIS SITUATION MAY NEED TO BE LOOKED AT
DURING THE LATE AFTERNOON. SIGNIFICANT SNOW WILL FALL DURING A
SHORT PERIOD BETWEEN TONIGHT AND TOMORROW MORNING. A FOOT IS
POSSIBLE IN THE HIGHER TERRAIN OF THE CASCADES WITH SEVERAL INCHES
EXPECTED EAST OF THE CASCADES IN KLAMATH COUNTY. ON SUNDAY IN THE
POSTFRONTAL ENVIRONMENT EXPECT SNOW SHOWERS ABOVE 3500 FEET AND
RAIN SHOWERS IN THE LOWER ELEVATIONS. RIDGING WILL BUILD OVER THE
REGION SUNDAY NIGHT...ESSENTIALLY ENDING THE PRECIPITATION OVER
THE CWA.
MODELS HAVE BEEN VERY PERSISTENT WITH UPPER RIDGING FROM MONDAY
THROUGH WEDNESDAY OVER NORTHERN CA AND SOUTHWESTERN OR...WITH THE
RESULTANT WEATHER IMPACTS BEING MORNING FOG MONDAY THROUGH
WEDNESDAY IN THE FAVORED LOW ELEVATION AREAS LIKE THE ROGUE AND
ILLINOIS VALLEYS...AND THE UMPQUA BASIN. A WEAK WARM FRONT BRUSHES
THE COAST ON WEDNESDAY BUT WILL NOT LIKELY RESULT IN ANY
SIGNIFICANT PRECIPITATION. GFS AND ECMWF BOTH PUT AN END TO THE
DRY WEATHER ON THANKSGIVING DAY BUT THEIR SOLUTIONS ARE STILL
FAIRLY DIFFERENT. THERE ARE STILL UNKNOWNS REGARDING THE FORECAST
FOR THURSDAY...BUT AT THIS POINT IT SEEMS REASONABLE TO EXPECT
LIGHT SNOW IN THE MOUNTAINS AND LIGHT RAIN IN THE VALLEYS ON LATE
THURSDAY. IT STILL SEEMS THERE WILL NOT BE A LARGE STORM FOR
THANKSGIVING DAY TRAVELERS IN THE REGION.
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 7 AM PST SUNDAY FOR ORZ027-ORZ028-
ORZ029-ORZ030.
WIND ADVISORY UNTIL 7 AM PST SUNDAY FOR ORZ031.
HIGH WIND WARNING UNTIL 4 AM PST SUNDAY FOR ORZ021-ORZ022.
CA...WIND ADVISORY UNTIL 4 AM PST SUNDAY FOR CAZ081.
PACIFIC COASTAL WATERS...STORM WARNING UNTIL 4 AM PST SUNDAY FOR
PZZ350-PZZ370.
HAZARDOUS SEAS WARNING UNTIL 4 AM PST MONDAY FOR PZZ350-PZZ356-
PZZ370-PZZ376.
GALE WARNING UNTIL 4 AM PST SUNDAY FOR PZZ356-PZZ376.
$$
DDG
000
FXUS66 KMFR 220502
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
902 PM PST SAT NOV 21 2009
.DISCUSSION...TIGHT...RAPIDLY DEVELOPING DEEP SURFACE LOW MOVING
RAPIDLY TOWARD THE NORTHERN OREGON COAST. NAM POSITION SLIGHTLY
TO FAR NORTH AND EAST. EXPECT THE TRACK TO BE SOUTH OF NAM
FORECAST POSITION. CURRENT FORECAST TAKE THIS INTO ACCOUNT AND
LOOK GOOD. STORM FORCE WINDS ALREADY IN THE OUTER WATERS NORTH
OF THE CAPE AND WINDS SHOULD COME UP RAPIDLY IN THE NEXT 3 HOURS
ALONG THE COAST. PROGS SHOWS THE WEATHER SETTLING DOWN SUNDAY AND
MONDAY...THEN HIGH PRESSURE DOMINATING UNTIL THE END OF NEXT WEEK.
NO UPDATES NEEDED THIS EVENING.
&&
.AVIATION...CURRENT VFR CEILINGS WILL BE SHORT-LIVED AS THE
OFFSHORE FRONT DROPS CEILING TO MVFR IN LOW CLOUDS AND SHOWERS IN
THE NEXT FEW HOURS. COASTAL TERMINALS WILL LIKELY BE IMPACTED BY
LOW LEVEL WIND SHEAR WITH GUSTY WINDS TO 35KT BUT EVEN STRONGER
50-60KT WINDS JUST ABOVE THE SURFACE. STRONG WINDS WILL ALSO
IMPACT THE CASCADES AND THE EAST SIDE LATE TONIGHT AND SUNDAY
MORNING. MOUNTAINS AND EAST SIDE WILL HAVE SNOW LATE TONIGHT AND
SUNDAY MORNING...REDUCING VISIBILITIES. MOUNTAIN OBSCURATION WILL
BE WIDESPREAD BY TONIGHT THROUGH SUNDAY AS DEEP MOISTURE PUSHES
INTO THE REGION.
&&
.PREV DISCUSSION... /ISSUED 301 PM PST SAT NOV 21 2009/
DISCUSSION...QUICK-MOVING DEVELOPING FRONTAL SYSTEM WILL IMPACT
THE CWA TONIGHT THROUGH SUNDAY MORNING. THE MAIN IMPACTS WILL BE
STRONG WINDS AND SOME SNOW OVER THE CASCADES AND THE EAST SIDE.
THE FAST MOVEMENT OF THIS SYSTEM...ALONG WITH MORE WESTERLY
WINDS...WILL FAVOR THE CASCADES RECEIVING MORE SNOWFALL AND THE
MOUNT SHASTA AREA RECEIVING LESS THAN THE PREVIOUS STORM. MODELS
HAVE SETTLED ON A 990MB LOW CENTERED WEST OF THE WA/OR BORDER LATE
TONIGHT. THE STRONGEST WINDS WILL IMPACT COASTAL WATERS AND
COASTAL ZONES TONIGHT...WITH WINDS AFFECTING THE CASCADES THROUGH
THE EAST SIDE LATE TONIGHT THROUGH SUNDAY MORNING. VERY STRONG H8
FLOW OF 50KT IS NOTED OVER NORTHWESTERN PORTION OF THE CWA LATE
TONIGHT...BUT STABILITY SHOULD KEEP MOST OF THIS AREA FROM GETTING
ADVISORY LEVEL WINDS. THIS SITUATION MAY NEED TO BE LOOKED AT
DURING THE LATE AFTERNOON. SIGNIFICANT SNOW WILL FALL DURING A
SHORT PERIOD BETWEEN TONIGHT AND TOMORROW MORNING. A FOOT IS
POSSIBLE IN THE HIGHER TERRAIN OF THE CASCADES WITH SEVERAL INCHES
EXPECTED EAST OF THE CASCADES IN KLAMATH COUNTY. ON SUNDAY IN THE
POSTFRONTAL ENVIRONMENT EXPECT SNOW SHOWERS ABOVE 3500 FEET AND
RAIN SHOWERS IN THE LOWER ELEVATIONS. RIDGING WILL BUILD OVER THE
REGION SUNDAY NIGHT...ESSENTIALLY ENDING THE PRECIPITATION OVER
THE CWA.
MODELS HAVE BEEN VERY PERSISTENT WITH UPPER RIDGING FROM MONDAY
THROUGH WEDNESDAY OVER NORTHERN CA AND SOUTHWESTERN OR...WITH THE
RESULTANT WEATHER IMPACTS BEING MORNING FOG MONDAY THROUGH
WEDNESDAY IN THE FAVORED LOW ELEVATION AREAS LIKE THE ROGUE AND
ILLINOIS VALLEYS...AND THE UMPQUA BASIN. A WEAK WARM FRONT BRUSHES
THE COAST ON WEDNESDAY BUT WILL NOT LIKELY RESULT IN ANY
SIGNIFICANT PRECIPITATION. GFS AND ECMWF BOTH PUT AN END TO THE
DRY WEATHER ON THANKSGIVING DAY BUT THEIR SOLUTIONS ARE STILL
FAIRLY DIFFERENT. THERE ARE STILL UNKNOWNS REGARDING THE FORECAST
FOR THURSDAY...BUT AT THIS POINT IT SEEMS REASONABLE TO EXPECT
LIGHT SNOW IN THE MOUNTAINS AND LIGHT RAIN IN THE VALLEYS ON LATE
THURSDAY. IT STILL SEEMS THERE WILL NOT BE A LARGE STORM FOR
THANKSGIVING DAY TRAVELERS IN THE REGION.
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 7 AM PST SUNDAY FOR ORZ027-ORZ028-
ORZ029-ORZ030.
WIND ADVISORY UNTIL 7 AM PST SUNDAY FOR ORZ031.
HIGH WIND WARNING UNTIL 4 AM PST SUNDAY FOR ORZ021-ORZ022.
CA...WIND ADVISORY UNTIL 4 AM PST SUNDAY FOR CAZ081.
PACIFIC COASTAL WATERS...STORM WARNING UNTIL 4 AM PST SUNDAY FOR
PZZ350-PZZ370.
HAZARDOUS SEAS WARNING UNTIL 4 AM PST MONDAY FOR PZZ350-PZZ356-
PZZ370-PZZ376.
GALE WARNING UNTIL 4 AM PST SUNDAY FOR PZZ356-PZZ376.
$$
DDG
000
FXUS66 KPQR 220442
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
841 PM PST SAT NOV 21 2009
.SYNOPSIS...A STRONG PACIFIC COLD FRONT WILL MOVE INLAND OVERNIGHT AS
A DEEP SURFACE LOW OFF THE COAST MOVES NORTHEAST INTO WASHINGTON.
A WEAK RIDGE OF HIGH PRESSURE WILL FOLLOW SUNDAY AFTERNOON AND
NIGHT...BEFORE THE NEXT FRONTAL SYSTEM ARRIVES LATER ON MONDAY.
&&
.SHORT TERM...MODELS ARE IN REASONABLY GOOD AGREEMENT SHOWING THE
DEEP SURFACE LOW MOVING ONTO THE CENTRAL WA COAST OR POSSIBLY A BIT S
AROUND 09Z. HOWEVER AT 00Z MODELS WERE ABOUT 4 MB TOO HIGH COMPARED
WITH SHIP REPORTS W OF 130W NEAR THE LOW. MODELS ARE IN GOOD
AGREEMENT ON THE UPPER FEATURES...WITH A STRONG SHORTWAVE MOVING
ACROSS THE FORECAST AREA TONIGHT...DIGGING SLIGHTLY TO THE ESE.
TIMING OF THE COLD FRONT IN ALL MODELS INDICATES FRONTAL PASSAGE ON
THE COAST AROUND MIDNIGHT. HAVE ISSUED A HIGH WIND WARNING FOR THE
WILLAPA HILLS TO GO ALONG WITH THE COASTAL WARNING AND INLAND VALLEY
WIND ADVISORIES. WINDS INLAND LOOK GUSTY WITH THE FRONT BUT
ESPECIALLY AFTER THE FRONT AND LOW MOVE INLAND AS THERE WILL BE
STRONG PRES RISES IN THE OVERNIGHT HOURS.
DOPPLER RADAR SHOWS THE PRECIP FIELD HAS FINALLY SPREAD TO THE
CASCADES THIS EVENING. WILL CONTINUE THE WINTER STORM WARNING FOR THE
CASCADES AS MOISTURE...STRENGTH OF THE FRONT AND THE POST FRONTAL
WESTERLY OROGRAPHIC FLOW ALL FAVOR SIGNIFICANT SNOWFALL FOR LATER
TONIGHT AND SUN.
A WEAK UPPER RIDGE WILL BUILD OVER THE FORECAST AREA SUN NIGHT AND
MON FOLLOWING THE FRONT. BEST CHANCES FOR PRECIP MON AND TUE WILL
SHIFT N INTO WA WITH WARM FRONT OVERRUNNING. THE UPPER RIDGE HOLDS
COLD FRONT AT BAY UNTIL AFTER TUE NIGHT. RW
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...WEAK HIGH PRES
RIDGE OVER THE FORECAST AREA CONTINUES TO
PUSH ENERGY NORTH OF FORECAST AREA MID WEEK. IT MANAGES TO DELAY THE
ARRIVAL OF A SECOND SYSTEM THROUGH THUR. MODEL SOLUTIONS DIVERGE
TOWARD THE END OF THE WEEK AND HAVE LITTLE CONFIDENCE IN THEM. AT
THIS TIME WILL GO WITH CLIMATOLOGY UNTIL THERE IS SOME CONSISTENCY
BETWEEN THE MODELS..
&&
.AVIATION...AREAS OF MVFR CONDITIONS ALONG THE COAST THIS EVENING
WILL EXPAND INLAND TONIGHT AS THE RAIN SHIELD FROM THE NEXT STRONG
SYSTEM APPROACHES. SOUTH WINDS WILL INCREASE THROUGH 09Z AND THEN
TURN WESTERLY FROM WEST TO EAST AS THE ASSOCIATED STRONG COLD FRONT
SWINGS ACROSS THE AREA. A MIX OF VFR AND MVFR CONDITIONS ARE
EXPECTED SUNDAY MORNING IN STRONG UNSTABLE ONSHORE FLOW.
KPDX AND APPROACHES...VFR CONDITIONS ARE EXPECTED THROUGH 06Z...THEN
MVFR CONDITIONS WILL DEVELOP AS A COLD FRONT APPROACHES. SOUTH TO
SOUTHWEST WINDS MAY BECOME QUITE STRONG AROUND 12Z AS A STRONG
GRADIENT DEVELOPS OVER THE NORTH VALLEY AS THE LOW MOVES INLAND.
WIND GUSTS NEAR 50 MPH ARE POSSIBLE. A MIX OF VFR AND MVFR
CONDITIONS ARE EXPECTED SUNDAY MORNING IN STRONG UNSTABLE ONSHORE
FLOW.
&&
.MARINE...GALE FORCE SOUTH WINDS WILL STRENGTHEN TO STORM FORCE
LATER THIS EVENING AS A POTENT LOW MOVES NORTH OF THE COASTAL WATERS
AND INLAND ALONG THE WASHINGTON COAST. WINDS WILL TURN W TO NW ON
SUNDAY AND BEGIN EASING. SEAS TONIGHT WILL LIKELY PEAK AROUND 20 FT
...BUT WILL DROP QUICKLY TO THE MID TEENS ON SUN.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
WA/OR...STORM WARNING FOR THE COASTAL WATERS FROM CAPE SHOALWATER TO
FLORENCE THROUGH 3 AM SUNDAY MORNING.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR CONDITIONS
THROUGH SUN EVENING.
WINTER STORM WARNING FOR THE S WA AND N AND CENTRAL OREGON
CASCADES TONIGHT AND SUNDAY.
HIGH WIND WARNING FOR THE S WA/N AND CENTRAL OREGON COAST...
AND WILLAPA HILLS TONIGHT.
WIND ADVISORY FOR THE WILLAMETTE VALLEY...THE LOWER
COLUMBIA...AND THE I-5 CORRIDOR FOR THIS EVENING
THROUGH SUNDAY MORNING.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS66 KPDT 220426
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
826 PM PST SAT NOV 21 2009
.UPDATE...A DEVELOPING FRONT IS APPROACHING THE PACIFIC NORTHWEST
COAST AND WILL COME ASHORE BEFORE MIDNIGHT. RADAR ON THE WEST SIDE
OF THE CASCADES IS SHOWING SUBSTANTIAL RETURNS AND LIGHT RAIN HAS
BEEN FALLING IN PORTLAND AND SEATTLE FOR A COUPLE OF HOURS. STAMPEDE
PASS IS REPORTING MODERATE SNOW AT THIS TIME BUT AM NOT SEEING SNOW
ON ANY OF THE WEB CAMS IN THE CASCADE PASSES. EXPECT THAT
PRECIPITATION WILL BEGIN IN THE NEXT HOUR OR TWO NEAR THE CASCADE
CREST AND WORK ITS WAY ACROSS THE AREA OVERNIGHT. WINDS HAVE BEEN
LIGHT BUT RADAR VELOCITY RETURNS ARE INCREASING ON BOTH LOCAL AND
PORTLAND AND SEATTLE RADARS SHOWING THAT STRONGER WINDS WILL BE
PRESENT ALOFT BEFORE LONG. WIND PROFILER DATA SHOWS AN INCREASING
TREND AS WELL. WATER VAPOR LOOP SHOWS AN AREA OF DARKENING BEHIND
THE FRONT THAT IS INCREASING IN SIZE AND STRENGTH AS THE FRONT
DEVELOPS. ALTHOUGH WINDS WILL TAKE A FEW HOURS TO TAKE OFF...WILL
LEAVE WIND GRIDS AS IS THOUGH STRONG WINDS MAY BE SPOTTY IN COVERAGE
AT FIRST. LATEST OBSERVATIONS ARE STARTING TO SHOW SOME 15 TO 25 MPH
WINDS SO WIND FORECAST...ADVISORIES AND WARNINGS LOOK GOOD.
TEMPERATURES ARE IN MANY CASES NOT TOO FAR FROM FORECAST OVERNIGHT
LOW TEMPERATURES WHICH IS A BIT CONCERNING BUT AS SOUTH WINDS
INCREASE...TEMPERATURES SHOULD INCREASE SO WILL LEAVE FORECAST AS
IS. OVERALL...FORECAST IS IN GOOD SHAPE. NO UPDATE PLANNED. PERRY
&&
.PREV DISCUSSION... /ISSUED 332 PM PST SAT NOV 21 2009/
SHORT TERM...TONIGHT THROUGH MONDAY...THOUGHTS HAVE CHANGED LITTLE
FROM THE PREVIOUS OVERNIGHT SHIFT. MODELS REMAINED VERY CONSISTENT
WITH THE PROGRESSION OF THE SYSTEM ACROSS THE AREA. WITH A COUPLE OF
PRONOUNCED ISSUES DEALT WITH TODAY.
FIRST, DECIDED TO FOLLOW THE SURFACE LOW AS SHOWN BY THE NAM WITH
THE 18Z GFS NOW LENDING THE CLOSEST SUPPORT OF RECENT RUNS. THIS
GIVES A VERY TIGHT PRESSURE GRADIENT ACROSS MOST OF THE AREA AS THE
SURFACE LOW TRACKS ACROSS THE WASHINGTON CASCADES AND THE LOWER
COLUMBIA BASIN BEFORE LIFTING NORTHEAST LATER TOMORROW. THESE
GRADIENTS, COMBINED WITH A VERY STABLE LOWER LEVEL AIR MASS, WILL
GIVE A PROLONGED PERIOD OF STRONG WINDS ALOFT DOWN TOWARD THE
SURFACE. WILL ISSUE NUMEROUS WIND ADVISORIES AND HIGH WIND WARNINGS
AS A RESULT.
THE SECOND ISSUE DEALS WITH SNOWFALL. SNOW LEVEL WILL BE SOMEWHAT
VARIABLE WITH A BRIEF PERIOD OF WARM AIR ADVECTION AS WARM DIFFLUENT
AIR CROSSES THE CASCADES TONIGHT. THE WASHINGTON CASCADES WILL SEE
SIGNIFICANT ACCUMULATIONS MAINLY TONIGHT WITH THE MAJOR PASSES
IMPACTED. DO THINK MAINLY WESTERN AREAS WILL BEAR THE BRUNT AFTER
THE COLD FRONT PASSES LATER TONIGHT AND SUNDAY. THE BLUE MOUNTAINS
WILL START SEEING ACCUMULATIONS LATER TONIGHT AT THE HIGHER
ELEVATIONS AND PASSES BUT SNOW LEVELS WILL DROP AND ACCUMULATION
RATES WILL INCREASE MAINLY TOMORROW AFTER THE COLD FRONT PASSES AND
A NORTHWESTERLY FLOW DEVELOPS. BOTH AREAS WILL SEE SIGNIFICANT
BLOWING SNOW BUT DONT HAVE THE CONFIDENCE TO GO WITH A BLIZZARD
WARNING, BUT IT BEARS WATCHING HOWEVER.
OTHER MOUNTAIN AREAS WILL SEE SNOW AND MAYBE SOME BLOWING AS WELL,
BUT SHOULD STAY BELOW ADVISORY AMOUNTS. PRECIPITATION SHOULD BEGIN
TAPERING OFF ACROSS THE WEST BY TOMORROW AFTERNOON AND GRADUALLY
TAPER OFF ACROSS THE EAST TOMORROW EVENING. /JBONK
LONG TERM...MONDAY NIGHT THROUGH SATURDAY...A WEAK SYSTEM WILL
BREAK UP MONDAY NIGHT IT RIDES OVER A BUILDING UPPER LEVEL RIDGE.
THE BUILDING RIDGE WILL MOVE SLOWLY EAST OVER THE PACIFIC NORTHWEST
TUESDAY. THE DEPARTING SYSTEM WILL COMBINE WILL UPSLOPE FLOW IN THE
MOUNTAINS TO KEEP A SLIGHT CHANCE OF SHOWERS IN NORTHEAST OREGON
TUESDAY. ALSO...SLOPOVER PRECIPITATION MAY OCCUR NEAR THE CASCADES.
SUBSIDENCE ASSOCIATED WITH THE RIDGE WILL PROVIDE LIGHT WINDS AND
CLEARING SKIES WITH THE STRONG SURFACE INVERSIONS TUESDAY NIGHT. IN
THE LOWER COLUMBIA BASIN PATCHY FOG AND FREEZING FOG WILL FORM AT
NIGHT UNDER THE INVERSIONS AND KEEP DAYTIME TEMPERATURES WEDNESDAY
BELOW NORMAL. AT HIGHER ELEVATIONS THE SURFACE INVERSIONS WILL BREAK
DURING THE DAY AND WARMER AIR ALOFT ASSOCIATED WITH THE RIDGE WILL
REACH THE SURFACE TO PRODUCE LARGE DIURNAL TEMPERATURE SPREADS.
WEDNESDAY NIGHT THROUGH FRIDAY THERE ARE DRAMATIC DIFFERENCES
BETWEEN THE GFS AND ECMWF MODELS EVEN THOUGH BOTH HAVE SOUTHWEST
FLOW AT 500 MB. THE 0Z ECMWF HAS A MORE PROGRESSIVE PATTERN WITH A
FRONT AT AN ANGLE TO THE 500 MB FLOW THAT WILL MOVE INTO EASTERN
WASHINGTON AND OREGON AND FORM A DEFORMATION ZONE OVER THE BLUE
MOUNTAINS THAT DROPS HALF AN INCH OF RAIN THURSDAY. THE 12Z GFS HAS
THE FRONT PARALLEL TO THE 500 MB FLOW SO IT REMAINS OFFSHORE UNTIL
FRIDAY. THE GFS ENSEMBLE RUNS SHOW 500 MB FLOW RUNNING TO BOTH
EXTREMES WITH NO CLUSTERING. DECIDED TO MAKE LITTLE CHANGE TO
EXISTING FORECAST WITH A CHANCE OF POPS MOST PLACES AND LIKELY POPS
OVER THE MOUNTAINS. THINK ECMWF IS OVERBLOWN WITH AMOUNT OF
PRECIPITATION UNLESS THE DEFORMATION BAND DOES SET UP...BUT DID
TREND TOWARD IT BY KEEPING AT LEAST A CHANCE OF POPS ACROSS THE
AREA. WHEN THE 12Z RUN OF THE ECMWF ARRIVED IT WAS SLOWER WITH NO
DEFORMATION BAND...BUT IT STILL SUPPORTED THE FASTER ARRIVAL OF THE
FRONT DURING THE DAY THURSDAY. BOTH MODELS HAD PRECIPITATION FRIDAY
WITH THE GFS PUSHING THE FRONT THROUGH AND THE ECMWF MOVING THE
UPPER LEVEL TROUGH THROUGH. WITH LOW CONFIDENCE DUE TO MODEL
DIFFERENCES KEPT A LOW CHANCE POPS ACROSS THE AREA SATURDAY.
COONFIELD
AVIATION...0Z TAFS...VFR CONDITIONS WILL PREVAIL IN MOST AREAS
THROUGH 04Z WITH BROKEN MID LEVEL CEILINGS. ANOTHER PACIFIC WEATHER
SYSTEM WILL MOVE INTO THE AREA TONIGHT AND EARLY SUNDAY MORNING WITH
RAIN AND MOUNTAIN SNOW. THIS WILL CAUSE AREAS OF MVFR CONDITIONS.
IFR WITH POSSIBLY EVEN LIFR CONDITIONS IN LOCAL AREAS WITH RAIN AND
SNOW...ESPECIALLY NEAR ANY MOUNTAIN RANGES OR OVER THE CENTRAL
OREGON PLATEAUS NEAR TAF SITE KRDM. WINDS OF 10 TO 20 KTS WITH GUSTS
TO 30 KTS FROM THE SOUTHWEST WILL BE COMMON IN ALL AREAS TODAY.
HOWEVER THE WINDS WILL INCREASE OVERNIGHT TONIGHT AS PRESSURE
GRADIENTS TIGHTEN UP AHEAD OF THE NEXT WEATHER SYSTEM. DURING THAT
TIME WINDS ARE EXPECTED TO INCREASE TO AT LEAST 15 TO 25 KTS WITH
GUSTS TO 40 KTS OR POSSIBLY EVEN HIGHER INTO SUNDAY. 76
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 41 47 31 43 / 80 70 10 10
ALW 39 48 32 43 / 90 80 10 10
PSC 37 51 30 44 / 90 50 10 10
YKM 32 45 29 44 / 90 40 10 10
HRI 38 49 29 45 / 80 50 10 10
ELN 34 39 26 39 / 90 70 10 20
RDM 35 45 24 47 / 80 40 10 10
LGD 36 42 23 40 / 80 80 20 10
GCD 34 41 21 44 / 70 60 10 10
DLS 37 49 32 47 / 80 40 20 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING UNTIL 10 AM PST SUNDAY FOR ORZ049-050.
WINTER STORM WARNING UNTIL 7 PM PST SUNDAY FOR ORZ502.
HIGH WIND WARNING FROM 1 AM TO 4 PM PST SUNDAY FOR ORZ042.
WIND ADVISORY UNTIL 1 PM PST SUNDAY FOR ORZ043.
WIND ADVISORY UNTIL 7 PM PST SUNDAY FOR ORZ501-504.
WINTER WEATHER ADVISORY UNTIL 7 PM PST SUNDAY FOR ORZ503.
WIND ADVISORY FROM 4 AM TO 4 PM PST SUNDAY FOR ORZ041-044.
WA...WINTER WEATHER ADVISORY UNTIL 4 PM PST SUNDAY FOR WAZ501-502.
WINTER STORM WARNING UNTIL 7 PM PST SUNDAY FOR WAZ030.
WIND ADVISORY UNTIL 7 PM PST SUNDAY FOR WAZ029.
WIND ADVISORY FROM 4 AM TO 4 PM PST SUNDAY FOR WAZ024-028.
&&
THREAT INDEX
SUNDAY : RED
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
83/76/76
000
FXUS65 KBOI 220339
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
838 PM MST SAT NOV 21 2009
.DISCUSSION...THE LATEST DATA AND NAM MODEL RUN FIT FORECAST TRENDS
WELL...SO NOT PLANNING ON MAKING ANY CHANGES THIS EVENING. WILL...
HOWEVER...UPDATE THE WINTER WEATHER BULLETIN TO INCLUDE THE UPPER
WEISER RIVER ZONE 33. MOST OF THE SNOWFALL...WHICH WILL BE LOCALLY
HEAVY IN THE MOUNTAINS...WILL OCCUR IN A 3-6 HOUR PERIOD IN THE WARM
SECTOR AHEAD OF THE FRONT...STARTING LATE TONIGHT IN SE OREGON
ENDING IN SW IDAHO EARLY SUNDAY AFTERNOON. THE SNOW WILL TAPER OFF
TO SNOW SHOWERS AFTER THE COLD FRONT MOVES THROUGH PROVIDING
ADDITIONAL LIGHT SNOW ACCUMS. WINDS WILL INCREASE AS WELL AND
COMBINE WITH THE SNOWFALL FOR AREAS OF BLOWING AND DRIFTING SNOW.
&&
.AVIATION...THICKENING AND LOWERING CLOUDS TONIGHT. WIDESPREAD
MOUNTAIN OBSCURATION AND IFR CONDITIONS IN SNOW SHOWERS DEVELOPING
OVER SOUTHEAST OREGON AFTER 09Z AND SOUTHWEST IDAHO AFTER 12Z. IFR
CONDITIONS WILL CONTINUE IN SOUTHWEST IDAHO MOUNTAINS AND WESTERN
MAGIC VALLEY THROUGH SUNDAY AFTERNOON. CONDITIONS WILL IMPROVE TO
VFR IN SOUTHEAST OREGON AND THE TREASURE VALLEY OF SOUTHWEST IDAHO
BY SUNDAY AFTERNOON. GUSTY SOUTHEAST SURFACE WINDS TONIGHT WILL
SHIFT TO THE WEST BY SUNDAY AFTERNOON. WINDS ALOFT WILL BE STRONG
FROM THE NORTHWEST.
&&
.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH MONDAY...WINDS WILL BUILD TONIGHT FROM
THE SOUTHEAST AND SOUTH THEN SHIFT TO SW AND NW SUNDAY BEHIND A FAST
MOVING COLD FRONT. HUGE..IE...-4/-6 TO +10/+15 MB PRESSURE FALL/RISE
COUPLET STAYS TO OUR NW AND N FOR LOCALLY VERY WINDY CONDITIONS
ACROSS SE OREGON AND BREEZY AREAS FOR SW IDAHO...BUT NO HEADLINES
FOR WIND. SNOW AND AREAS OF BLOWING/DRIFTING SNOW ARE EXPECTED WITH
THIS FAST MOVING SYSTEM SUNDAY SO AN ADVISORY FOR SNOW AND BLOWING
SNOW HAS BEEN HOISTED ACROSS BAKER COUNTY...THE WEST CENTRAL AND
BOISE MOUNTAINS. GUSTY NW WINDS DIMINISH RAPIDLY MONDAY NIGHT AS
HIGH PRESSURE BUILDS IN...WITH LIGHT WINDS AND MOSTLY CLEAR SKIES.
COUPLED WITH NEW SNOW COVER...GENERALLY ABOVE 3500 FEET...LOW TEMPS
WILL PLUMMET TO SINGLE DIGITS COLDEST SPOTS SUCH AS FAIRFIELD AND
MID 20S...TEENS ACROSS THE RELATIVELY MILDER LOCALES. LIGHT WINDS
AND A COLD START MONDAY LOOK TO KEEP TEMPS BELOW NORMAL AND NEAR TO
BELOW MOS.
LONG TERM...MONDAY NIGHT THROUGH SATURDAY...UPPER RIDGE BUILDS INTO
THE PACIFIC NW ON TUESDAY. WEAK SYSTEM MOVING THROUGH THE PANHANDLE
TUESDAY AFTERNOON WILL DO LITTLE MORE THAT INCREASE CLOUDS OVER THE
WEST CENTRAL MTNS. WITH WARMING ALOFT...INVERSION SETS UP IN THE
LOWER ELEVATIONS FOR TUE/WED. INTRODUCED FOG INTO THE FORECAST FOR
TUESDAY NIGHT AND WEDNESDAY IN THE LOWER TREASURE...WEISER AND BAKER
VALLEYS. LESS CONFIDENT ON DEVELOPMENT OF FOG/STRATUS OVER BOISE
WEDNESDAY MORNING SO HAVE LEFT IT OUT FOR NOW. GOOD MODEL AGREEMENT
THAT INVERSION IS SHORT-LIVED...AS ANOTHER STORM ENTERS THE PAC NW
LATE IN THE WEEK. THE 12Z SOLUTIONS ARE IN BETTER AGREEMENT ON
BRINGING THE STORM THROUGH THE INTERMOUNTAIN NW ON FRIDAY. WINDS
AHEAD OF THE SYSTEM WOULD LIKELY CLEAR OUT ANY FOG/STRATUS IN THE
LOWER VALLEYS THANKSGIVING DAY. LOOKS LIKE RAIN IN THE VALLEYS ON
FRIDAY WITH MTN SNOW. PATTERN REMAINS ACTIVE THROUGH NEXT WEEKEND.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...WINTER WEATHER ADVISORY FROM 4 AM TO 2 PM MST SUNDAY FOR IDZ033.
WINTER WEATHER ADVISORY FROM 4 AM TO 2 PM MST SUNDAY FOR IDZ011-
IDZ013.
OR...WINTER WEATHER ADVISORY FROM 1 AM TO 10 AM PST SUNDAY FOR
ORZ062.
&&
$$
WEATHER.GOV/BOISE
DISCUSSION...BW
AVIATION.....JA
PREV SHORT TERM...VM
PREV LONG TERM....DG/DD
000
FXUS66 KPDT 212332 AAA
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
332 PM PST SAT NOV 21 2009
UPDATED AVIATION DISCUSSION
.SHORT TERM...TONIGHT THROUGH MONDAY...THOUGHTS HAVE CHANGED LITTLE
FROM THE PREVIOUS OVERNIGHT SHIFT. MODELS REMAINED VERY CONSISTENT
WITH THE PROGRESSION OF THE SYSTEM ACROSS THE AREA. WITH A COUPLE OF
PRONOUNCED ISSUES DEALT WITH TODAY.
FIRST, DECIDED TO FOLLOW THE SURFACE LOW AS SHOWN BY THE NAM WITH
THE 18Z GFS NOW LENDING THE CLOSEST SUPPORT OF RECENT RUNS. THIS
GIVES A VERY TIGHT PRESSURE GRADIENT ACROSS MOST OF THE AREA AS THE
SURFACE LOW TRACKS ACROSS THE WASHINGTON CASCADES AND THE LOWER
COLUMBIA BASIN BEFORE LIFTING NORTHEAST LATER TOMORROW. THESE
GRADIENTS, COMBINED WITH A VERY STABLE LOWER LEVEL AIR MASS, WILL
GIVE A PROLONGED PERIOD OF STRONG WINDS ALOFT DOWN TOWARD THE
SURFACE. WILL ISSUE NUMEROUS WIND ADVISORIES AND HIGH WIND WARNINGS
AS A RESULT.
THE SECOND ISSUE DEALS WITH SNOWFALL. SNOW LEVEL WILL BE SOMEWHAT
VARIABLE WITH A BRIEF PERIOD OF WARM AIR ADVECTION AS WARM DIFFLUENT
AIR CROSSES THE CASCADES TONIGHT. THE WASHINGTON CASCADES WILL SEE
SIGNIFICANT ACCUMULATIONS MAINLY TONIGHT WITH THE MAJOR PASSES
IMPACTED. DO THINK MAINLY WESTERN AREAS WILL BEAR THE BRUNT AFTER
THE COLD FRONT PASSES LATER TONIGHT AND SUNDAY. THE BLUE MOUNTAINS
WILL START SEEING ACCUMULATIONS LATER TONIGHT AT THE HIGHER
ELEVATIONS AND PASSES BUT SNOW LEVELS WILL DROP AND ACCUMULATION
RATES WILL INCREASE MAINLY TOMORROW AFTER THE COLD FRONT PASSES AND
A NORTHWESTERLY FLOW DEVELOPS. BOTH AREAS WILL SEE SIGNIFICANT
BLOWING SNOW BUT DONT HAVE THE CONFIDENCE TO GO WITH A BLIZZARD
WARNING, BUT IT BEARS WATCHING HOWEVER.
OTHER MOUNTAIN AREAS WILL SEE SNOW AND MAYBE SOME BLOWING AS WELL,
BUT SHOULD STAY BELOW ADVISORY AMOUNTS. PRECIPITATION SHOULD BEGIN
TAPERING OFF ACROSS THE WEST BY TOMORROW AFTERNOON AND GRADUALLY
TAPER OFF ACROSS THE EAST TOMORROW EVENING. /JBONK
.LONG TERM...MONDAY NIGHT THROUGH SATURDAY...A WEAK SYSTEM WILL
BREAK UP MONDAY NIGHT IT RIDES OVER A BUILDING UPPER LEVEL RIDGE.
THE BUILDING RIDGE WILL MOVE SLOWLY EAST OVER THE PACIFIC NORTHWEST
TUESDAY. THE DEPARTING SYSTEM WILL COMBINE WILL UPSLOPE FLOW IN THE
MOUNTAINS TO KEEP A SLIGHT CHANCE OF SHOWERS IN NORTHEAST OREGON
TUESDAY. ALSO...SLOPOVER PRECIPITATION MAY OCCUR NEAR THE CASCADES.
SUBSIDENCE ASSOCIATED WITH THE RIDGE WILL PROVIDE LIGHT WINDS AND
CLEARING SKIES WITH THE STRONG SURFACE INVERSIONS TUESDAY NIGHT. IN
THE LOWER COLUMBIA BASIN PATCHY FOG AND FREEZING FOG WILL FORM AT
NIGHT UNDER THE INVERSIONS AND KEEP DAYTIME TEMPERATURES WEDNESDAY
BELOW NORMAL. AT HIGHER ELEVATIONS THE SURFACE INVERSIONS WILL BREAK
DURING THE DAY AND WARMER AIR ALOFT ASSOCIATED WITH THE RIDGE WILL
REACH THE SURFACE TO PRODUCE LARGE DIURNAL TEMPERATURE SPREADS.
WEDNESDAY NIGHT THROUGH FRIDAY THERE ARE DRAMATIC DIFFERENCES
BETWEEN THE GFS AND ECMWF MODELS EVEN THOUGH BOTH HAVE SOUTHWEST
FLOW AT 500 MB. THE 0Z ECMWF HAS A MORE PROGRESSIVE PATTERN WITH A
FRONT AT AN ANGLE TO THE 500 MB FLOW THAT WILL MOVE INTO EASTERN
WASHINGTON AND OREGON AND FORM A DEFORMATION ZONE OVER THE BLUE
MOUNTAINS THAT DROPS HALF AN INCH OF RAIN THURSDAY. THE 12Z GFS HAS
THE FRONT PARALLEL TO THE 500 MB FLOW SO IT REMAINS OFFSHORE UNTIL
FRIDAY. THE GFS ENSEMBLE RUNS SHOW 500 MB FLOW RUNNING TO BOTH
EXTREMES WITH NO CLUSTERING. DECIDED TO MAKE LITTLE CHANGE TO
EXISTING FORECAST WITH A CHANCE OF POPS MOST PLACES AND LIKELY POPS
OVER THE MOUNTAINS. THINK ECMWF IS OVERBLOWN WITH AMOUNT OF
PRECIPITATION UNLESS THE DEFORMATION BAND DOES SET UP...BUT DID
TREND TOWARD IT BY KEEPING AT LEAST A CHANCE OF POPS ACROSS THE
AREA. WHEN THE 12Z RUN OF THE ECMWF ARRIVED IT WAS SLOWER WITH NO
DEFORMATION BAND...BUT IT STILL SUPPORTED THE FASTER ARRIVAL OF THE
FRONT DURING THE DAY THURSDAY. BOTH MODELS HAD PRECIPITATION FRIDAY
WITH THE GFS PUSHING THE FRONT THROUGH AND THE ECMWF MOVING THE
UPPER LEVEL TROUGH THROUGH. WITH LOW CONFIDENCE DUE TO MODEL
DIFFERENCES KEPT A LOW CHANCE POPS ACROSS THE AREA SATURDAY.
COONFIELD
&&
.AVIATION...0Z TAFS...VFR CONDITIONS WILL PREVAIL IN MOST AREAS
THROUGH 04Z WITH BROKEN MID LEVEL CEILINGS. ANOTHER PACIFIC WEATHER
SYSTEM WILL MOVE INTO THE AREA TONIGHT AND EARLY SUNDAY MORNING WITH
RAIN AND MOUNTAIN SNOW. THIS WILL CAUSE AREAS OF MVFR CONDITIONS.
IFR WITH POSSIBLY EVEN LIFR CONDITIONS IN LOCAL AREAS WITH RAIN AND
SNOW...ESPECIALLY NEAR ANY MOUNTAIN RANGES OR OVER THE CENTRAL
OREGON PLATEAUS NEAR TAF SITE KRDM. WINDS OF 10 TO 20 KTS WITH GUSTS
TO 30 KTS FROM THE SOUTHWEST WILL BE COMMON IN ALL AREAS TODAY.
HOWEVER THE WINDS WILL INCREASE OVERNIGHT TONIGHT AS PRESSURE
GRADIENTS TIGHTEN UP AHEAD OF THE NEXT WEATHER SYSTEM. DURING THAT
TIME WINDS ARE EXPECTED TO INCREASE TO AT LEAST 15 TO 25 KTS WITH
GUSTS TO 40 KTS OR POSSIBLY EVEN HIGHER INTO SUNDAY. 76
.PRELIMINARY POINT TEMPS/POPS...
PDT 41 47 31 43 / 80 70 10 10
ALW 39 48 32 43 / 90 80 10 10
PSC 37 51 30 44 / 90 50 10 10
YKM 32 45 29 44 / 90 40 10 10
HRI 38 49 29 45 / 80 50 10 10
ELN 34 39 26 39 / 90 70 10 20
RDM 35 45 24 47 / 80 40 10 10
LGD 36 42 23 40 / 80 80 20 10
GCD 34 41 21 44 / 70 60 10 10
DLS 37 49 32 47 / 80 40 20 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING FROM 7 PM THIS EVENING TO 10 AM PST SUNDAY FOR
ORZ049-050.
WINTER STORM WARNING FROM 10 PM THIS EVENING TO 7 PM PST SUNDAY
FOR ORZ502.
HIGH WIND WARNING FROM 1 AM TO 4 PM PST SUNDAY FOR ORZ042.
WIND ADVISORY FROM 10 PM THIS EVENING TO 1 PM PST SUNDAY FOR
ORZ043.
WIND ADVISORY FROM 10 PM THIS EVENING TO 7 PM PST SUNDAY FOR
ORZ501-504.
WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 7 PM PST
SUNDAY FOR ORZ503.
WIND ADVISORY FROM 4 AM TO 4 PM PST SUNDAY FOR ORZ041-044.
WA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 4 PM PST
SUNDAY FOR WAZ501-502.
WINTER STORM WARNING FROM 10 PM THIS EVENING TO 7 PM PST SUNDAY
FOR WAZ030.
WIND ADVISORY FROM 10 PM THIS EVENING TO 7 PM PST SUNDAY FOR
WAZ029.
WIND ADVISORY FROM 4 AM TO 4 PM PST SUNDAY FOR WAZ024-028.
&&
THREAT INDEX
SUNDAY : RED
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
87/76/76
000
FXUS66 KMFR 212301
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
301 PM PST SAT NOV 21 2009
...UPDATED FOR HIGH WIND WARNING FOR COASTAL ZONES...WIND
ADVISORIES FOR SHASTA VALLEY AND LAKE COUNTY...AND WINTER WEATHER
ADVISORY FOR SNOW AND BLOWING SNOW OVER THE CASCADES AND MUCH OF
KLAMATH COUNTY.
.DISCUSSION...QUICK-MOVING DEVELOPING FRONTAL SYSTEM WILL IMPACT
THE CWA TONIGHT THROUGH SUNDAY MORNING. THE MAIN IMPACTS WILL BE
STRONG WINDS AND SOME SNOW OVER THE CASCADES AND THE EAST SIDE.
THE FAST MOVEMENT OF THIS SYSTEM...ALONG WITH MORE WESTERLY
WINDS...WILL FAVOR THE CASCADES RECEIVING MORE SNOWFALL AND THE
MOUNT SHASTA AREA RECEIVING LESS THAN THE PREVIOUS STORM. MODELS
HAVE SETTLED ON A 990MB LOW CENTERED WEST OF THE WA/OR BORDER LATE
TONIGHT. THE STRONGEST WINDS WILL IMPACT COASTAL WATERS AND
COASTAL ZONES TONIGHT...WITH WINDS AFFECTING THE CASCADES THROUGH
THE EAST SIDE LATE TONIGHT THROUGH SUNDAY MORNING. VERY STRONG H8
FLOW OF 50KT IS NOTED OVER NORTHWESTERN PORTION OF THE CWA LATE
TONIGHT...BUT STABILITY SHOULD KEEP MOST OF THIS AREA FROM GETTING
ADVISORY LEVEL WINDS. THIS SITUATION MAY NEED TO BE LOOKED AT
DURING THE LATE AFTERNOON. SIGNIFICANT SNOW WILL FALL DURING A
SHORT PERIOD BETWEEN TONIGHT AND TOMORROW MORNING. A FOOT IS
POSSIBLE IN THE HIGHER TERRAIN OF THE CASCADES WITH SEVERAL INCHES
EXPECTED EAST OF THE CASCADES IN KLAMATH COUNTY. ON SUNDAY IN THE
POSTFRONTAL ENVIRONMENT EXPECT SNOW SHOWERS ABOVE 3500 FEET AND
RAIN SHOWERS IN THE LOWER ELEVATIONS. RIDGING WILL BUILD OVER THE
REGION SUNDAY NIGHT...ESSENTIALLY ENDING THE PRECIPITATION OVER
THE CWA.
MODELS HAVE BEEN VERY PERSISTENT WITH UPPER RIDGING FROM MONDAY
THROUGH WEDNESDAY OVER NORTHERN CA AND SOUTHWESTERN OR...WITH THE
RESULTANT WEATHER IMPACTS BEING MORNING FOG MONDAY THROUGH
WEDNESDAY IN THE FAVORED LOW ELEVATION AREAS LIKE THE ROGUE AND
ILLINOIS VALLEYS...AND THE UMPQUA BASIN. A WEAK WARM FRONT BRUSHES
THE COAST ON WEDNESDAY BUT WILL NOT LIKELY RESULT IN ANY
SIGNIFICANT PRECIPITATION. GFS AND ECMWF BOTH PUT AN END TO THE
DRY WEATHER ON THANKSGIVING DAY BUT THEIR SOLUTIONS ARE STILL
FAIRLY DIFFERENT. THERE ARE STILL UNKNOWNS REGARDING THE FORECAST
FOR THURSDAY...BUT AT THIS POINT IT SEEMS REASONABLE TO EXPECT
LIGHT SNOW IN THE MOUNTAINS AND LIGHT RAIN IN THE VALLEYS ON LATE
THURSDAY. IT STILL SEEMS THERE WILL NOT BE A LARGE STORM FOR
THANKSGIVING DAY TRAVELERS IN THE REGION.
&&
.AVIATION...MID CLOUDS ARE STREAMING OVER THE REGION TODAY AND
WILL GRADUALLY LOWER DURING THE DAY AND EVENING. CURRENT VFR
CEILINGS WILL BE SHORT-LIVED AS ANOTHER FRONT DROPS MOST TERMINALS
TO MVFR AND OCCASIONAL IFR IN LOW CLOUDS AND SHOWERS BY THIS
EVENING. COASTAL TERMINALS WILL LIKELY BE IMPACTED BY LOW LEVEL
WIND SHEAR WITH GUSTY WINDS TO 35KT BUT EVEN STRONGER 50-60KT
WINDS JUST ABOVE THE SURFACE. STRONG WINDS WILL ALSO IMPACT THE
CASCADES AND THE EAST SIDE LATE TONIGHT AND SUNDAY MORNING.
MOUNTAINS AND EAST SIDE WILL HAVE SNOW TONIGHT AND SUNDAY
MORNING...REDUCING VISIBILITIES. MOUNTAIN OBSCURATION WILL BE
WIDESPREAD BY TONIGHT THROUGH SUNDAY AS DEEP MOISTURE PUSHES INTO
THE REGION.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 AM PST
SUNDAY FOR ORZ027-ORZ028-ORZ029-ORZ030.
WIND ADVISORY FROM 10 PM THIS EVENING TO 7 AM PST SUNDAY FOR
ORZ031.
HIGH WIND WARNING UNTIL 4 AM PST SUNDAY FOR ORZ021-ORZ022.
CA...WIND ADVISORY FROM 10 PM THIS EVENING TO 4 AM PST SUNDAY FOR
CAZ081.
PACIFIC COASTAL WATERS...STORM WARNING UNTIL 4 AM PST SUNDAY FOR
PZZ350-PZZ370.
GALE WARNING UNTIL 4 PM PST THIS AFTERNOON FOR PZZ350-PZZ370.
HAZARDOUS SEAS WARNING UNTIL 4 AM PST MONDAY FOR PZZ350-PZZ356-
PZZ370-PZZ376.
GALE WARNING UNTIL 4 AM PST SUNDAY FOR PZZ356-PZZ376.
$$
KEENE
000
FXUS66 KPDT 212246
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
246 PM PST SAT NOV 21 2009
.SHORT TERM...TONIGHT THROUGH MONDAY...THOUGHTS HAVE CHANGED LITTLE
FROM THE PREVIOUS OVERNIGHT SHIFT. MODELS REMAINED VERY CONSISTENT
WITH THE PROGRESSION OF THE SYSTEM ACROSS THE AREA. WITH A COUPLE OF
PRONOUNCED ISSUES DEALT WITH TODAY.
FIRST, DECIDED TO FOLLOW THE SURFACE LOW AS SHOWN BY THE NAM WITH
THE 18Z GFS NOW LENDING THE CLOSEST SUPPORT OF RECENT RUNS. THIS
GIVES A VERY TIGHT PRESSURE GRADIENT ACROSS MOST OF THE AREA AS THE
SURFACE LOW TRACKS ACROSS THE WASHINGTON CASCADES AND THE LOWER
COLUMBIA BASIN BEFORE LIFTING NORTHEAST LATER TOMORROW. THESE
GRADIENTS, COMBINED WITH A VERY STABLE LOWER LEVEL AIR MASS, WILL
GIVE A PROLONGED PERIOD OF STRONG WINDS ALOFT DOWN TOWARD THE
SURFACE. WILL ISSUE NUMEROUS WIND ADVISORIES AND HIGH WIND WARNINGS
AS A RESULT.
THE SECOND ISSUE DEALS WITH SNOWFALL. SNOW LEVEL WILL BE SOMEWHAT
VARIABLE WITH A BRIEF PERIOD OF WARM AIR ADVECTION AS WARM DIFFLUENT
AIR CROSSES THE CASCADES TONIGHT. THE WASHINGTON CASCADES WILL SEE
SIGNIFICANT ACCUMULATIONS MAINLY TONIGHT WITH THE MAJOR PASSES
IMPACTED. DO THINK MAINLY WESTERN AREAS WILL BEAR THE BRUNT AFTER
THE COLD FRONT PASSES LATER TONIGHT AND SUNDAY. THE BLUE MOUNTAINS
WILL START SEEING ACCUMULATIONS LATER TONIGHT AT THE HIGHER
ELEVATIONS AND PASSES BUT SNOW LEVELS WILL DROP AND ACCUMULATION
RATES WILL INCREASE MAINLY TOMORROW AFTER THE COLD FRONT PASSES AND
A NORTHWESTERLY FLOW DEVELOPS. BOTH AREAS WILL SEE SIGNIFICANT
BLOWING SNOW BUT DONT HAVE THE CONFIDENCE TO GO WITH A BLIZZARD
WARNING, BUT IT BEARS WATCHING HOWEVER.
OTHER MOUNTAIN AREAS WILL SEE SNOW AND MAYBE SOME BLOWING AS WELL,
BUT SHOULD STAY BELOW ADVISORY AMOUNTS. PRECIPITATION SHOULD BEGIN
TAPERING OFF ACROSS THE WEST BY TOMORROW AFTERNOON AND GRADUALLY
TAPER OFF ACROSS THE EAST TOMORROW EVENING. /JBONK
.LONG TERM...MONDAY NIGHT THROUGH SATURDAY...A WEAK SYSTEM WILL
BREAK UP MONDAY NIGHT IT RIDES OVER A BUILDING UPPER LEVEL RIDGE.
THE BUILDING RIDGE WILL MOVE SLOWLY EAST OVER THE PACIFIC NORTHWEST
TUESDAY. THE DEPARTING SYSTEM WILL COMBINE WILL UPSLOPE FLOW IN THE
MOUNTAINS TO KEEP A SLIGHT CHANCE OF SHOWERS IN NORTHEAST OREGON
TUESDAY. ALSO...SLOPOVER PRECIPITATION MAY OCCUR NEAR THE CASCADES.
SUBSIDENCE ASSOCIATED WITH THE RIDGE WILL PROVIDE LIGHT WINDS AND
CLEARING SKIES WITH THE STRONG SURFACE INVERSIONS TUESDAY NIGHT. IN
THE LOWER COLUMBIA BASIN PATCHY FOG AND FREEZING FOG WILL FORM AT
NIGHT UNDER THE INVERSIONS AND KEEP DAYTIME TEMPERATURES WEDNESDAY
BELOW NORMAL. AT HIGHER ELEVATIONS THE SURFACE INVERSIONS WILL BREAK
DURING THE DAY AND WARMER AIR ALOFT ASSOCIATED WITH THE RIDGE WILL
REACH THE SURFACE TO PRODUCE LARGE DIURNAL TEMPERATURE SPREADS.
WEDNESDAY NIGHT THROUGH FRIDAY THERE ARE DRAMATIC DIFFERENCES
BETWEEN THE GFS AND ECMWF MODELS EVEN THOUGH BOTH HAVE SOUTHWEST
FLOW AT 500 MB. THE 0Z ECMWF HAS A MORE PROGRESSIVE PATTERN WITH A
FRONT AT AN ANGLE TO THE 500 MB FLOW THAT WILL MOVE INTO EASTERN
WASHINGTON AND OREGON AND FORM A DEFORMATION ZONE OVER THE BLUE
MOUNTAINS THAT DROPS HALF AN INCH OF RAIN THURSDAY. THE 12Z GFS HAS
THE FRONT PARALLEL TO THE 500 MB FLOW SO IT REMAINS OFFSHORE UNTIL
FRIDAY. THE GFS ENSEMBLE RUNS SHOW 500 MB FLOW RUNNING TO BOTH
EXTREMES WITH NO CLUSTERING. DECIDED TO MAKE LITTLE CHANGE TO
EXISTING FORECAST WITH A CHANCE OF POPS MOST PLACES AND LIKELY POPS
OVER THE MOUNTAINS. THINK ECMWF IS OVERBLOWN WITH AMOUNT OF
PRECIPITATION UNLESS THE DEFORMATION BAND DOES SET UP...BUT DID
TREND TOWARD IT BY KEEPING AT LEAST A CHANCE OF POPS ACROSS THE
AREA. WHEN THE 12Z RUN OF THE ECMWF ARRIVED IT WAS SLOWER WITH NO
DEFORMATION BAND...BUT IT STILL SUPPORTED THE FASTER ARRIVAL OF THE
FRONT DURING THE DAY THURSDAY. BOTH MODELS HAD PRECIPITATION FRIDAY
WITH THE GFS PUSHING THE FRONT THROUGH AND THE ECMWF MOVING THE
UPPER LEVEL TROUGH THROUGH. WITH LOW CONFIDENCE DUE TO MODEL
DIFFERENCES KEPT A LOW CHANCE POPS ACROSS THE AREA SATURDAY.
COONFIELD
&&
.AVIATION...18Z TAFS...VFR CONDITIONS WILL PREVAIL IN MOST AREAS
THROUGH 03Z WITH SCATTERED TO BROKEN MID LEVEL CEILINGS. ANOTHER
PACIFIC WEATHER SYSTEM WILL MOVE INTO THE AREA TONIGHT AND EARLY
SUNDAY MORNING WITH RAIN AND MOUNTAIN SNOW INCREASING. THIS WILL
CAUSE AREAS OF MVFR CONDITIONS. IFR WITH POSSIBLY EVEN LIFR
CONDITIONS IN LOCAL AREAS WITH RAIN AND SNOW...ESPECIALLY NEAR ANY
MOUNTAIN RANGES OR OVER THE CENTRAL OREGON PLATEAUS NEAR TAF SITE
KRDM. WINDS OF 10 TO 20 KTS WITH GUSTS TO 30 KTS FROM THE SOUTHWEST
WILL BE COMMON IN ALL AREAS TODAY. HOWEVER THE WINDS WILL INCREASE
OVERNIGHT TONIGHT AS PRESSURE GRADIENTS TIGHTEN UP AHEAD OF THE NEXT
WEATHER SYSTEM. DURING THAT TIME WINDS ARE EXPECTED TO INCREASE TO
AT LEAST 15 TO 25 KTS WITH GUSTS TO 40 KTS OR POSSIBLY EVEN HIGHER
INTO SUNDAY. 76
.PRELIMINARY POINT TEMPS/POPS...
PDT 41 47 31 43 / 80 70 10 10
ALW 39 48 32 43 / 90 80 10 10
PSC 37 51 30 44 / 90 50 10 10
YKM 32 45 29 44 / 90 40 10 10
HRI 38 49 29 45 / 80 50 10 10
ELN 34 39 26 39 / 90 70 10 20
RDM 35 45 24 47 / 80 40 10 10
LGD 36 42 23 40 / 80 80 20 10
GCD 34 41 21 44 / 70 60 10 10
DLS 37 49 32 47 / 80 40 20 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING FROM 7 PM THIS EVENING TO 10 AM PST SUNDAY FOR
ORZ049-050.
WINTER STORM WARNING FROM 10 PM THIS EVENING TO 7 PM PST SUNDAY
FOR ORZ502.
HIGH WIND WARNING FROM 1 AM TO 4 PM PST SUNDAY FOR ORZ042.
WIND ADVISORY FROM 10 PM THIS EVENING TO 1 PM PST SUNDAY FOR
ORZ043.
WIND ADVISORY FROM 10 PM THIS EVENING TO 7 PM PST SUNDAY FOR
ORZ501-504.
WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 7 PM PST
SUNDAY FOR ORZ503.
WIND ADVISORY FROM 4 AM TO 4 PM PST SUNDAY FOR ORZ041-044.
WA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 4 PM PST
SUNDAY FOR WAZ501-502.
WINTER STORM WARNING FROM 10 PM THIS EVENING TO 7 PM PST SUNDAY
FOR WAZ030.
WIND ADVISORY FROM 10 PM THIS EVENING TO 7 PM PST SUNDAY FOR
WAZ029.
WIND ADVISORY FROM 4 AM TO 4 PM PST SUNDAY FOR WAZ024-028.
&&
THREAT INDEX
SUNDAY : RED
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
87/76/76
000
FXUS66 KPQR 212226
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
220 PM PST SAT NOV 21 2009
.SYNOPSIS...A STRONG PACIFIC FRONTAL SYSTEM IS APPROACHING THE COAST
THIS AFTERNOON WITH A WARM FRONT MOVING INLAND THIS AFTERNOON AND
EVENING...AND THE ASSOCIATED COLD FRONT QUICKLY FOLLOWING TONIGHT AS
A SURFACE LOW PRESSURE SYSTEM MOVES INLAND NEAR THE WA OREGON BORDER.
A WEAK RIDGE OF HIGH PRESSURE WILL FOLLOW SUN AFTERNOON AND
NIGHT...BEFORE THE NEXT FRONTAL SYSTEM ARRIVES MON.
&&
.SHORT TERM...MODELS ARE STILL SHOWING DIFFERENCES IN TRACK OF THE
SURFACE LOW COMING IN TONIGHT. THE GENERAL CONSENSUS IS TO BRING IT
IN JUST NORTH OF THE WASHINGTON/OREGON BORDER. MODELS ARE IN BETTER
AGREEMENT ON THE UPPER FEATURES...WITH A STRONG SHORTWAVE MOVING
ACROSS THE FORECAST AREA TONIGHT...DIGGING TO THE ESE. TIMING OF THE
COLD FRONT IN ALL MODELS INDICATES FRONTAL PASSAGE ON THE COAST
AROUND MIDNIGHT TONIGHT. HAVE UPGRADED THE HIGH WIND WATCH FOR THE
ENTIRE COAST TO A HIGH WIND WARNING. WINDS INLAND LOOK GUSTY WITH AND
BEHIND THE FRONT AS THERE ARE STRONG PRESSURE RISES BEHIND THE
FRONT...WILL ISSUE AN ADVISORY FOR THE WILLAMETTE VALLEY..I-5
CORRIDOR AND THE LOWER COLUMBIA FOR TONIGHT AND EARLY SUNDAY MORNING
WITH THE AFTERNOON PACKAGE.
DOPPLER RADAR INDICATES THAT SHOWERS HAVE SIGNIFICANTLY DIMINISHED
OVER THE AREA WITH ONLY AN ISOLATED SHOWER OR TWO OVER THE SOUTH
WASHINGTON CASCADES AND HAVE ALREADY CANCELLED THE SNOW ADVISORY FOR
THE CASCADES. WILL CONTINUE THE WINTER STORM WARNING FOR THE
CASCADES AS MOISTURE...STRENGTH OF THE FRONT AND THE POST FRONTAL
FLOW ALL FAVOR SIGNIFICANT SNOWFALL FOR LATER TONIGHT AND SUN.
A WEAK UPPER RIDGE WILL BUILD OVER THE FORECAST AREA SUNDAY NIGHT AND
MONDAY FOLLOWING THE FRONT. BEST CHANCES FOR PRECIPITATION MONDAY AND
TUESDAY WILL SHIFT N INTO WA WITH WARM FRONT OVERRUNNING. THE UPPER
RIDGE HOLDS COLD FRONT AT BAY UNTIL AFTER TUE NIGHT. LIKENS
.LONG TERM...WEAK HIGH PRES RIDGE OVER THE FORECAST AREA CONTINUES TO
PUSH ENERGY NORTH OF FORECAST AREA MID WEEK. IT MANAGES TO DELAY THE
ARRIVAL OF A SECOND SYSTEM THROUGH THUR. MODEL SOLUTIONS DIVERGE
TOWARD THE END OF THE WEEK AND HAVE LITTLE CONFIDENCE IN THEM. AT
THIS TIME WILL GO WITH CLIMATOLOGY UNTIL THERE IS SOME CONSISTENCY
BETWEEN THE MODELS..
&&
.AVIATION...PREDOMINATELY VFR WITH SCATTERED SHOWERS...WHICH MAY
BRING VERY BRIEF MVFR CIGS. CONDITIONS REMAIN VFR THIS
AFTERNOON...THOUGH WILL SEE INCREASING MVFR ALONG THE COAST AS WARM
FRONT SWINGS ACROSS THE REGION. COLD FRONT TONIGHT WILL BRING
INCREASING MVFR AFTER 04Z...AND INCREASING SOUTHERLY WINDS SOME OF
WHICH MAY BE QUITE STRONG IN SOME AREAS. LOCATION OF STRONG WINDS
WILL DEPEND ON WHERE THE LOW COMES INLAND.
KPDX AND APPROACHES...VFR CONDITIONS THROUGH 05Z...THEN INCREASING
MVFR CIGS AS COLD FRONT APPROACHES. WATCH FOR POTENTIAL OF LOW LEVEL
WIND SHEAR BETWEEN 06Z AND 18Z TONIGHT AND TOMORROW MORNING AS WILL
SEE INCREASING SOUTH WINDS ALOFT...BLOWING OVER THE LOW LEVEL
EASTERLY FLOW COMING FROM GORGE. SOUTH TO SOUTHWEST WINDS MAY BE
QUITE STRONG AROUND 12Z AS STRONG GRADIENT DEVELOPS OVER NORTH
VALLEY AS LOW MOVES INLAND. WIND GUSTS NEAR 50 TO 55 MPH ARE
POSSIBLE. WOLFE
&&
.MARINE...GALE FORCE SOUTH WINDS WILL STRENGTHEN TO STORM FORCE AS
POTENT LOW MOVES OVER THE COASTAL WATERS. STORM WARNING FOR THE
COASTAL WATERS FOR TONIGHT. WINDS TURN MORE W TO NW ON SUNDAY AND
BEGIN EASING. SEAS TONIGHT LIKELY TO PEAK IN THE 20 TO 25 FT
RANGE...BUT WILL DROP QUICKLY TO THE MID TEENS ON SUN.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
WA/OR...GALE WARNING FOR COASTAL WATERS FROM CAPE SHOALWATER TO
FLORENCE FOR THIS AFTERNOON.
STORM WARNING FOR COASTAL WATERS FROM CAPE SHOALWATER TO
FLORENCE FOR TONIGHT.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR CONDITIONS
THROUGH SUN.
WINTER STORM WARNING FOR THE S WA AND N AND CENTRAL OREGON
CASCADES TONIGHT AND SUNDAY.
HIGH WIND WARNING FOR THE SOUTHERN WASHINGTON/NORTHERN AND
CENTRAL OREGON COAST TONIGHT.
WIND ADVISORY FOR THE WILLAMETTE VALLEY..THE LOWER
COLUMBIA..AND THE I-5 CORRIDOR FOR THIS EVENING THROUGH
SUNDAY MORNING.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS65 KBOI 212205
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
305 PM MST SAT NOV 21 2009
.SHORT TERM...TONIGHT THROUGH MONDAY...WINDS WILL BUILD TONIGHT
FROM THE SOUTHEAST AND SOUTH THEN SHIFT TO SW AND NW SUNDAY BEHIND
A FAST MOVING COLD FRONT. HUGE..IE...-4/-6 TO +10/+15 MB PRESSURE
FALL/RISE COUPLET STAYS TO OUR NW AND N FOR LOCALLY VERY WINDY
CONDITIONS ACROSS SE OREGON AND BREEZY AREAS FOR SW IDAHO...BUT NO
HEADLINES FOR WIND. SNOW AND AREAS OF BLOWING/DRIFTING SNOW ARE
EXPECTED WITH THIS FAST MOVING SYSTEM SUNDAY SO AN ADVISORY FOR
SNOW AND BLOWING SNOW HAS BEEN HOISTED ACROSS BAKER COUNTY...THE
WEST CENTRAL AND BOISE MOUNTAINS. GUSTY NW WINDS DIMINISH RAPIDLY
MONDAY NIGHT AS HIGH PRESSURE BUILDS IN...WITH LIGHT WINDS AND
MOSTLY CLEAR SKIES. COUPLED WITH NEW SNOW COVER...GENERALLY ABOVE
3500 FEET...LOW TEMPS WILL PLUMMET TO SINGLE DIGITS COLDEST SPOTS
SUCH AS FAIRFIELD AND MID 20S...TEENS ACROSS THE RELATIVELY MILDER
LOCALES. LIGHT WINDS AND A COLD START MONDAY LOOK TO KEEP TEMPS
BELOW NORMAL AND NEAR TO BELOW MOS.
.LONG TERM...MONDAY NIGHT THROUGH SATURDAY...UPPER RIDGE BUILDS INTO
THE PACIFIC NW ON TUESDAY. WEAK SYSTEM MOVING THROUGH THE PANHANDLE
TUESDAY AFTERNOON WILL DO LITTLE MORE THAT INCREASE CLOUDS OVER THE
WEST CENTRAL MTNS. WITH WARMING ALOFT...INVERSION SETS UP IN THE
LOWER ELEVATIONS FOR TUE/WED. INTRODUCED FOG INTO THE FORECAST FOR
TUESDAY NIGHT AND WEDNESDAY IN THE LOWER TREASURE...WEISER AND BAKER
VALLEYS. LESS CONFIDENT ON DEVELOPMENT OF FOG/STRATUS OVER BOISE
WEDNESDAY MORNING SO HAVE LEFT IT OUT FOR NOW. GOOD MODEL AGREEMENT
THAT INVERSION IS SHORT-LIVED...AS ANOTHER STORM ENTERS THE PAC NW
LATE IN THE WEEK. THE 12Z SOLUTIONS ARE IN BETTER AGREEMENT ON
BRINGING THE STORM THROUGH THE INTERMOUNTAIN NW ON FRIDAY. WINDS
AHEAD OF THE SYSTEM WOULD LIKELY CLEAR OUT ANY FOG/STRATUS IN THE
LOWER VALLEYS THANKSGIVING DAY. LOOKS LIKE RAIN IN THE VALLEYS ON
FRIDAY WITH MTN SNOW. PATTERN REMAINS ACTIVE THROUGH NEXT WEEKEND.
&&
.AVIATION...WIDESPREAD IFR CONDITIONS IN SNOW DEVELOPING SUNDAY
MORNING...OVER SE OREGON AFTER 06Z AND SW ID AFTER 09Z. WILL SEE 4-6
HOURS OF IFR CONDITIONS AT BOISE SUNDAY MORNING. IFR CONDITIONS
CONTINUE IN SW IDAHO MTNS AND WESTERN MAGIC VALLEY THROUGH SUNDAY
AFTERNOON. CONDITIONS IMPROVE TO VFR IN SE OREGON AND TREASURE
VALLEY OF SW IDAHO SUNDAY AFTERNOON. GUSTY SE SURFACE WINDS EARLY
SUNDAY MORNING SHIFTING TO THE WEST IN THE AFTERNOON. STRONG
WESTERLY WINDS ALOFT OF 40-60 KTS ON SUNDAY.
OUTLOOK...DEVELOPMENT OF INVERSION NEXT WEEK WILL BRING CHANCE OF
IFR CONDITIONS IN FOG/STRATUS TO TREASURE/BAKER/WEISER VALLEYS ON
WEDNESDAY.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...WINTER WEATHER ADVISORY FROM 4 AM TO 2 PM MST SUNDAY FOR IDZ011-
IDZ013.
OR...WINTER WEATHER ADVISORY FROM 1 AM TO 10 AM PST SUNDAY FOR ORZ062.
&&
$$
WEATHER.GOV/BOISE
SHORT TERM...VM
LONG TERM....DG/DD
AVIATION.....DG
000
FXUS66 KPDT 211743 AAA
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
943 AM PST SAT NOV 21 2009
UPDATED AVIATION DISCUSSION
.UPDATE...RELATIVELY FEW CHANGES MADE TO TODAY`S FORECAST WITH
PRIMARY FOCUS BEING DIRECTED ON THE APPROACHING SYSTEM AFFECTING
TONIGHT AND TOMORROW. AN EARLY LOOK AT THE 12Z RUNS SHOW RATHER
GOOD CONTINUITY FROM THE NAM AND GFS REGARDING POSITION OF THE
SURFACE LOW SO WILL NEED TO WORK OUT THE DIFFERENCES AND RELATIVE
IMPACTS. AS PREVIOUSLY STATED, THE SPECIFIC TRACK OF THE LOW WILL
DETERMINE THE DIFFERENCE BETWEEN ADVISORY AND WARNING AMOUNTS AND
WIND SPEEDS. RECENTLY RELEASED PRECIPITATION ESTIMATES FROM
NESDIS INDICATE AVAILABLE MOISTURE AND RAIN RATES ARE LESS THAT
HAVE BEEN SEEN WITH THE MOST RECENT SYSTEM SO MAY BE LEANING
TOWARD THE OVERALL DRIER NAM QPF, BUT THIS MODEL STILL BRINGS
SIGNIFICANT QPF TO THE NORTHERN BLUE MOUNTAINS AFTER A BRIEF
PERIOD OF MODERATE PRECIP MAINLY TO THE WASHINGTON PORTION OF THE
CWA. /JBONK
&&
.AVIATION...18Z TAFS...VFR CONDITIONS WILL PREVAIL IN MOST AREAS
THROUGH 03Z WITH SCATTERED TO BROKEN MID LEVEL CEILINGS. ANOTHER
PACIFIC WEATHER SYSTEM WILL MOVE INTO THE AREA TONIGHT AND EARLY
SUNDAY MORNING WITH RAIN AND MOUNTAIN SNOW INCREASING. THIS WILL
CAUSE AREAS OF MVFR CONDITIONS. IFR WITH POSSIBLY EVEN LIFR
CONDITIONS IN LOCAL AREAS WITH RAIN AND SNOW...ESPECIALLY NEAR ANY
MOUNTAIN RANGES OR OVER THE CENTRAL OREGON PLATEAUS NEAR TAF SITE
KRDM. WINDS OF 10 TO 20 KTS WITH GUSTS TO 30 KTS FROM THE SOUTHWEST
WILL BE COMMON IN ALL AREAS TODAY. HOWEVER THE WINDS WILL INCREASE
OVERNIGHT TONIGHT AS PRESSURE GRADIENTS TIGHTEN UP AHEAD OF THE NEXT
WEATHER SYSTEM. DURING THAT TIME WINDS ARE EXPECTED TO INCREASE TO
AT LEAST 15 TO 25 KTS WITH GUSTS TO 40 KTS OR POSSIBLY EVEN HIGHER
INTO SUNDAY. 76
&&
.PREV DISCUSSION... /ISSUED 300 AM PST SAT NOV 21 2009/
SHORT TERM...TODAY THROUGH SUNDAY...THE BACK SIDE OF A VERY SHARP
AND DEEP UPPER TROUGH CONTINUES TO MOVE ACROSS THE REGION EARLY THIS
MORNING. THE ENERGY DIGGING DOWN THE BACK SIDE OF THE TROUGH IS
KEEPING A FEW SHOWERS...MOSTLY SNOW...GOING OVER PORTIONS OF THE
AREA...ESPECIALLY ALONG AND JUST EAST OF THE CASCADES. AS THIS
TROUGH EXITS THE AREA THIS MORNING SHOULD SEE THESE SHOWERS WIND
DOWN FURTHER...TO MAINLY A FEW ALONG THE CASCADE CREST. A POTENT
SYSTEM IS CURRENTLY TAKING SHAPE OUT ALONG 150W THIS MORNING. THIS
SYSTEM WILL SWING ACROSS THE REGION LATE TONIGHT AND ON SUNDAY.
THERE IS A CHANCE THAT A SURFACE LOW WILL FORM OFF THE NORTHWEST
OREGON COAST LATE TONIGHT AND THEN MOVE EAST ACROSS WASHINGTON STATE
SUNDAY. THERE IS SOME UNCERTAINTY AS TO THE TRACK OF THIS SURFACE
LOW AS SOME DATA POINTS TO IT SWINGING MORE NORTHEASTWARD THROUGH
WESTERN WASHINGTON INTO BRITISH COLUMBIA. THE TRACK OF THIS SURFACE
LOW WILL DETERMINE THE WEATHER CONDITIONS OVER OUR AREA SUNDAY. IF
THE LOW MOVES INTO THE INTERIOR NORTHWEST AS SOME DATA SUGGESTS THEN
WE WOULD SEE STRONG WINDS OVER CENTRAL OREGON...THE BLUE MOUNTAIN
FOOTHILLS...THE GRANDE RONDE VALLEY AND WALLOWA COUNTY. ALSO THERE
WOULD BE SIGNIFICANT PRECIP OVER MANY AREAS AS THE SYSTEM MOVES
THROUGH. ALSO THERE WOULD BE WESTERLY UPSLOPE FLOW BEHIND THE
SYSTEM. A QUICK CUT OFF OF PRECIP IN THE LEE OF THE CASCADES DUE TO
THE WEST FLOW WOULD LIMIT SNOW ALONG THE CASCADE EAST SLOPE ZONES.
MEANWHILE THE UPSLOPE FLOW INTO THE BLUE MOUNTAINS WOULD ALLOW
CONSIDERABLE POST SYSTEM SNOW ACCUMULATIONS. THE ALTERNATE SOLUTION
REDUCES THE WIND RISK ACROSS THE AREA...AND ALTERS THE FOCUS OF
PRECIP AND SNOW ACCUMULATIONS AWAY FROM THE BLUES AND TO THE
WASHINGTON CASCADE EAST SLOPES. AT THIS TIME WILL SIDE WITH THE
SOLUTIONS (NAM AND EUROPEAN) THAT ADVERTISE THE SURFACE LOW TRACKING
EAST INTO THE INTERIOR NORTHWEST. AS SUCH WILL ISSUE WIND AND WINTER
STORM WATCHES FOR THE AREAS MENTIONED ABOVE THAT WOULD BE AFFECTED
BY THE EASTERLY TRACK. WILL ONLY GO WITH WATCHES THOUGH DUE TO THE
CONTINUED UNCERTAINTY. 90
LONG TERM...SUNDAY NIGHT THROUGH NEXT SATURDAY...A WEATHER SYSTEM
WILL BE DEPARTING THE FORECAST AREA SUNDAY NIGHT WHILE AN UPPER
RIDGE BUILDS OVER THE REGION. THIS WILL PUSH MOST OF THE MOISTURE
WITH ANY NEW SYSTEMS THAT TRY TO MOVE INTO THE PACIFIC NORTHWEST UP
INTO SW CANADA AND EXTREME NW WASHINGTON. AS A RESULT OUR FORECAST
AREA WILL SEE MOSTLY DRY CONDITIONS WITH JUST ISOLATED TO SCATTERED
SHOWERS IN THE MOUNTAINS. THIS SCENARIO WILL PERSIST THROUGH
THURSDAY. THERE WILL BE PATCHY FOG DEVELOPMENT IN THE USUAL LOW
AREAS OF THE LOWER COLUMBIA BASIN AND ESPECIALLY ALONG THE LARGER
RIVERS SUCH AS THE COLUMBIA...YAKIMA AND SNAKE RIVERS. A PACIFIC
TROUGH WILL THEN MOVE INTO THE REGION AGAIN ON FRIDAY AND FRIDAY
NIGHT BRINGING ANOTHER CHANCE OF RAIN AND MOUNTAIN SNOW. THERE IS
CONSIDERABLE MODEL DIFFERENCES THAT FAR OUT IN THE EXTENDED PERIOD
SO WILL NOT MAKE ANY CHANGES TO THE CURRENT FORECAST WHICH IS
ALREADY REPRESENTATIVE FOR THAT SYSTEM. 88
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 48 37 47 31 / 10 80 70 10
ALW 49 38 48 32 / 10 80 70 10
PSC 52 36 51 30 / 10 80 50 10
YKM 49 32 48 29 / 10 80 40 10
HRI 50 35 49 29 / 10 80 50 10
ELN 46 32 45 26 / 20 80 50 10
RDM 44 34 45 24 / 20 70 40 10
LGD 43 36 43 22 / 20 80 80 20
GCD 42 33 42 21 / 10 70 60 10
DLS 50 37 49 32 / 20 80 40 20
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON FOR
ORZ501-504.
WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR ORZ502.
HIGH WIND WATCH FROM THIS EVENING THROUGH SUNDAY MORNING FOR
ORZ042-043.
HIGH WIND WATCH FROM 7 PM PST THIS EVENING THROUGH SUNDAY
MORNING FOR ORZ049-050.
WA...HIGH WIND WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON FOR
WAZ029.
WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR WAZ030.
&&
THREAT INDEX
TODAY : RED
SUNDAY : RED
MONDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
87
000
FXUS66 KPQR 211718
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
917 AM PST SAT NOV 21 2009
...UPDATED FOR HIGH WIND WATCH AND POSSIBLE WIND ADVISORY IN THE
WILLAMETTE VALLEY TONIGHT...
.SYNOPSIS...A WARM FRONT WILL APPROACH THE OREGON COAST THIS
AFTERNOON THEN PUSH INLAND THIS EVENING. A COLD FRONT WILL QUICKLY
FOLLOW TONIGHT AS A SURFACE LOW PRESSURE SYSTEM MOVES INLAND NEAR THE
WA OREGON BORDER. A WEAK RIDGE OF HIGH PRESSURE WILL FOLLOW SUN
AFTERNOON AND NIGHT...BEFORE THE NEXT FRONTAL SYSTEM ARRIVES MON.
&&
.SHORT TERM...LATEST MODEL RUNS CONTINUE TO EXHIBIT DIFFERENCES IN
TRACK OF THE SURFACE LOW COMING IN TONIGHT. UPPER FEATURES APPEAR
PRETTY WELL AGREED ON...WITH A STRONG SHORTWAVE MOVING ACROSS THE
FORECAST AREA TONIGHT...DIGGING TO THE ESE. GIVEN THE TRACT OF THE
UPPER VORT MAX AND THE NEGATIVE TILT OF THE UPPER TROUGH...CONTINUE
TO PREFER A MORE SOUTHERLY TRACK OF THE SURFACE LOW...AS SUCH PREFER
THE 00Z RUN OF THE ECMWF WHICH TAKES A SURFACE LOW E ROUGHLY ACROSS
KKLS AT 12Z SUN. TIMING OF THE COLD FRONT IN ALL MODELS INDICATES
FRONTAL PASSAGE ON THE COAST NOT UNTIL SOMETIME TONIGHT. GIVEN THE
CONTINUED UNCERTAINTIES IN THE MODELS...WILL EXTEND THE HIGH WIND
WATCH FOR THE N AND CENTRAL OREGON COAST TO INCLUDE THE SOUTHERN
WASHINGTON COAST...AND EXTEND IT TILL 6AM. WINDS INLAND LOOK GUSTY
WITH AND BEHIND THE FRONT AS THERE ARE STRONG PRESSURE RISES BEHIND
THE FRONT...EXPECT AN ADVISORY FOR SOME PORTION OF THE WILLAMETTE
VALLEY FOR LATE TONIGHT WILL BE NEEDED...WILL PROBABLY ISSUE WITH
AFTERNOON PACKAGE.
DOPPLER RADAR CONTINUES TO SHOW SHOWERS SPREADING OVER MOST OF THE
FORECAST AREA THIS MORNING AS WESTERLY FLOW ALOFT FOLLOWS THE UPPER
TROUGH. WITH UPPER RIDGING LATER TODAY...AND LOW LEVEL FLOW BACKING
MORE TO THE S...SHOULD SEE SHOWERS DROP OFF TODAY. OVERNIGHT SNOWFALL
AMOUNTS IN THE CASCADES SINCE LAST EVENING HAVE RANGED FROM ROUGHLY 4
TO 9 INCHES. FOR NOW WILL HANG ONTO THE SNOW ADVISORY FOR THE N
OREGON AND S WA CASCADES TODAY...ALTHOUGH WILL LIKELY SEE A
SIGNIFICANT DROPOFF IN SNOWFALL LATER THIS MORNING. WILL CONTINUE
THE WINTER STORM WARNING FOR THE CASCADES AS MOISTURE...STRENGTH OF
THE FRONT AND THE POST FRONTAL FLOW ALL FAVOR SIGNIFICANT SNOWFALL
LATER TONIGHT AND SUN.
CURRENT MODEL RUNS INDICATE BEST CHANCES FOR PRECIPITATION MONDAY
WILL SHIFT N INTO WA WITH WARM FRONT OVERRUNNING. THE UPPER RIDGE
HOLDS COLD FRONT AT BAY UNTIL MON NIGHT. LIKENS
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...WEAK HIGH PRES
BUILDS OVER THE FORECAST AREA MON NIGHT. MODELS SHOW A WEAK SYSTEM
APPROACH THE COAST EARLY TUE...BUT IT TRACKS FURTHER NORTH AND
LIGHTLY BRUSHES THE FAR NORTHWEST CORNER OF THE CWA. THIS RIDGE IS
MORE PERSISTENT THAN PREVIOUS MODEL RUNS SUGGESTED. IT MANAGES TO
DELAY THE ARRIVAL OF A SECOND SYSTEM THROUGH THUR. BY MID NEXT
WEEK...MODELS DISAGREE ON THE SOLUTION FOR THE WEEKEND. GFS MODEL
RUNS ARE INCONSISTENT...THE 06Z RUN HELD BACK ON PRECIP THROUGH THURS
NIGHT BUT THE CURRENT RUN SHOWS RAIN EXTENDING TO THE CASCADES THURS
NIGHT. SO FAR...MODELS SUGGEST A FAIRLY NICE WEEKEND AS ANOTHER UPPER
HIGH PRES TEMPORARILY SETS UP OVER THE PAC NW. LRAMIREZ
&&
.AVIATION...LITTLE CHANGE IN OVERALL CONDITIONS THIS MORNING.
PREDOMINATELY VFR WITH SCATTERED SHOWERS...WHICH MAY BRING VERY
BRIEF MVFR CIGS. CONDITIONS REMAIN VFR THROUGH TODAY...THOUGH WILL
SEE INCREASING MVFR ALONG THE COAST AFTER 20Z AS WARM FRONT SWINGS
ACROSS THE REGION. COLD FRONT TONIGHT WILL BRING INCREASING MVFR
AFTER 04Z...AND INCREASING SOUTHERLY WINDS.
KPDX AND APPROACHES...VFR CONDITIONS THROUGH 05Z...THEN INCREASING
MVFR CIGS AS COLD FRONT APPROACHES. WATCH FOR POTENTIAL OF LOW LEVEL
WIND SHEAR BETWEEN 00Z AND 06Z TONIGHT AS WILL SEE INCREASING SOUTH
WINDS ALOFT...BLOWING OVER THE LOW LEVEL EASTERLY FLOW COMING FROM
GORGE.ROCKEY/WOLFE
&&
.MARINE...NOT MUCH CHANGE. CONDITIONS WILL DETERIORATE LATER TODAY
AS WARM FRONT LIFTS ACROSS THE REGION. THIS WILL BRING GALE FORCE
SOUTH WINDS. HOWEVER...STRONG WINDS ARRIVE TONIGHT AS RATHER STRONG
LOW PRES PASSES ACROSS THE N OREGON COASTAL WATERS. STORM WARNING
FOR THE COASTAL WATERS FOR TONIGHT. WINDS TURN MORE W TO NW ON
SUNDAY AND BEGIN EASING. SEAS TONIGHT LIKELY TO PEAK IN THE 20 TO 25
FT RANGE...BUT WILL DROP QUICKLY ON SUN.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
WA/OR...GALE WARNING FOR COASTAL WATERS FROM CAPE SHOALWATER TO
FLORENCE FOR THIS AFTERNOON.
STORM WARNING FOR COASTAL WATERS FROM CAPE SHOALWATER TO
FLORENCE FOR TONIGHT.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR CONDITIONS
THROUGH SUN.
SNOW ADVISORY FOR THE SOUTH WASHINGTON AND NORTH OREGON
CASCADES THROUGH 4 PM.
WINTER STORM WARNING FOR THE S WA AND N AND CENTRAL OREGON
CASCADES TONIGHT AND SUNDAY.
HIGH WIND WATCH FOR THE SOUTHERN WASHINGTON/NORTHERN AND
CENTRAL OREGON COAST TONIGHT.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS66 KMFR 211703
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
903 AM PST SAT NOV 21 2009
.DISCUSSION...CURRENT FORECAST LOOKS GOOD OVER REGION WITH FRONT
ENTERING THE COASTAL WATERS TONIGHT...USHERING WINDY CONDITIONS
OVER THE COASTAL WATERS AND INTO THE COOS AND CURRY COUNTIES. HIGH
WIND WATCH IS ACCURATELY PORTRAYING CONDITIONS FOR TONIGHT AS
STRONG WINDS WILL IMPACT THE COASTAL COUNTIES...AND WILL LIKELY BE
ISSUING HIGH WIND WARNING FOR THAT AREA WITH THE AFTERNOON PACKAGE.
WILL BE LOOKING AT THE DATA AND PROGRESSION OF UPSTREAM DEVELOPING
STORM FURTHER TO DECIDE ON ANY POSSIBLE WIND ADVISORY FOR DOUGLAS
COUNTY AREA WITH NAM INTENSIFYING LOW A BIT ON RECENT MODEL RUNS.
ALSO...WILL BE FINE TUNING SNOW FORECAST FOR KLAMATH FALLS AREA
AND LOOKING AT SNOW ADVISORY FOR THAT AREA LATE TONIGHT INTO
SUNDAY MORNING. MODELS ARE STILL AGREEING ON DRY SOLUTION FOR
MONDAY THROUGH WEDNESDAY WITH A WEAK FRONT ENTERING THE AREA
THURSDAY. CURRENT SNOW LEVEL IS ABOUT 3500 FEET PER MFR
SOUNDING...AND LEVELS WILL RISE A BIT AHEAD OF FRONT AND THEN DROP
BEHIND THE FRONT TOMORROW MORNING.
&&
.AVIATION...FOG IN THE ROGUE VALLEY AND UMPQUA BASIN...RESULTING
IN IFR CONDITIONS...WILL LIFT TO VFR BY LATER THIS MORNING. VFR
CONDITIONS WILL BE SHORT-LIVED AS ANOTHER FRONT DROPS MOST
TERMINALS TO MVFR IN LOW CLOUDS AND SHOWERS BY THIS EVENING.
MOUNTAINS AND EAST SIDE WILL HAVE SNOW REDUCING VISIBILITIES
TONIGHT AND SUNDAY MORNING. MOUNTAIN OBSCURATION WILL BE
WIDESPREAD BY TONIGHT THROUGH SUNDAY AS DEEP MOISTURE PUSHES INTO
THE REGION.
&&
.PREV DISCUSSION... /ISSUED 405 AM PST SAT NOV 21 2009/
DISCUSSION...A FEW SHOWERS WILL LINGER ACROSS THE HIGHER TERRAIN
OF THE FORECAST AREA THIS MORNING BUT THE TREND IS FOR BRIEF
DRYING THIS AFTERNOON. BY EARLY EVENING ANOTHER PACIFIC FRONT WILL
MOVE INTO THE COASTAL WATERS. FIRST THE WARM FRONT WILL BRING
GUSTY SOUTH WINDS TO THE COAST TONIGHT. BOTH THE NAM AND GFS SHOW
BOUNDARY LAYER WINDS TO BE IN THE 40 TO 50 MPH RANGE. AS A RESULT
HAVE ISSUED A HIGH WIND WATCH AT THE COAST. THE STRONGEST WINDS
SHOULD OCCUR BETWEEN 10PM AND MIDNIGHT TONIGHT. FARTHER EAST
SOUTHWEST WINDS WILL ALSO PICK UP AHEAD OF THE FRONT. PART OF
HIGHWAY 31 RUNNING FROM PAISLEY TO SUMMER LAKE IN LAKE COUNTY IS
EXPECTED TO SEE ANOTHER ROUND OF GUSTY WINDS AND WIND ADVISORY MAY
BE NEEDED LATER. GUIDANCE ALSO INDICATES INCREASING WINDS IN THE
SHASTA VALLEY THIS EVENING ALTHOUGH WIND DIRECTION DOES NOT APPEAR
AS CONDUCIVE TO THE SPEED REACHING WARNING CRITERIA.
THE COLD FRONT WILL MOVE INTO SOUTHWEST OREGON THIS EVENING WITH
PRECIPITATION SPREADING INTO THE ROGUE VALLEY IN THE EARLY
EVENING. STEADY PRECIPITATION IS EXPECTED TO BE OVERNIGHT TONIGHT
AND THROUGH SUNDAY MORNING. SOUTHERLY WIND AHEAD OF THE FRONT
COULD DELAY COLD AIR FROM FILTERING INTO KLAMATH FALLS BUT BY LATE
TONIGHT THE FRONT IS EXPECTED TO BRING COLD AIR INTO THE EAST
SIDE. IF THE CURRENT QPF FORECAST HOLDS...WE MAY NEED A SNOW
ADVISORY FOR NORTHERN KLAMATH COUNTY FROM DIAMOND LAKE JUNCTION
NORTH THROUGH CHEMULT. BY SUNDAY AFTERNOON PRECIPITATION SHOULD
TAPER OFF TO SHOWERS AND BE CONFINED MAINLY IN UPSLOPE AREA AND
HIGHER TERRAIN.
THE LATEST GFS AND ECMWF CONTINUES WITH THE DRYING TREND FOR MOST
OF NEXT WEEK AS THE STORM TRACK SHIFTS NORTH. THE ECMWF BRINGS THE
NEXT COLD FRONT INLAND ON THANKSGIVING BUT THE GFS HOLDS THE FRONT
OFFSHORE BEFORE BRINGING THE FRONT INLAND DURING THAT NIGHT. HAVE
INTRODUCED A CHANCE POPS FOR THANKSGIVING DAY BUT CONFIDENCE ON
TIMING IS NOT VERY HIGH.
AVIATION...WIDESPREAD MVFR AT THE COAST THIS EVENING THROUGH
TONIGHT IN FREQUENT MODERATE RAIN. WINDS ALONG THE COAST WILL ALSO
BE VERY STRONG OVERNIGHT WITH LLWS POSSIBLE. MVFR CIGS AND VIS
SPREAD INLAND AND ARE MORE LIKELY AFTER 06Z TONIGHT. HIGHER MOUNTAINS
WILL BE OBSCURED OVERNIGHT.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WATCH FROM 4 PM PST THIS AFTERNOON THROUGH LATE
TONIGHT FOR ORZ021-ORZ022.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 PM
PST THIS AFTERNOON FOR PZZ350-PZZ356-PZZ370-PZZ376.
GALE WARNING FROM 1 PM THIS AFTERNOON TO 4 AM PST SUNDAY FOR
PZZ356-PZZ376.
HAZARDOUS SEAS WARNING UNTIL 4 PM PST SUNDAY FOR PZZ350-PZZ356-
PZZ370-PZZ376.
STORM WARNING FROM 4 PM THIS AFTERNOON TO 4 AM PST SUNDAY FOR
PZZ350-PZZ370.
GALE WARNING FROM 1 PM TO 4 PM PST THIS AFTERNOON FOR PZZ350-
PZZ370.
$$
NK
000
FXUS66 KPDT 211701
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
901 AM PST SAT NOV 21 2009
.UPDATE...RELATIVELY FEW CHANGES MADE TO TODAY`S FORECAST WITH
PRIMARY FOCUS BEING DIRECTED ON THE APPROACHING SYSTEM AFFECTING
TONIGHT AND TOMORROW. AN EARLY LOOK AT THE 12Z RUNS SHOW RATHER
GOOD CONTINUITY FROM THE NAM AND GFS REGARDING POSITION OF THE
SURFACE LOW SO WILL NEED TO WORK OUT THE DIFFERENCES AND RELATIVE
IMPACTS. AS PREVIOUSLY STATED, THE SPECIFIC TRACK OF THE LOW WILL
DETERMINE THE DIFFERENCE BETWEEN ADVISORY AND WARNING AMOUNTS AND
WIND SPEEDS. RECENTLY RELEASED PRECIPITATION ESTIMATES FROM
NESDES INDICATE AVAILABLE MOISTURE AND RAIN RATES ARE LESS THAT
HAVE BEEN SEEN WITH THE MOST RECENT SYSTEM SO MAY BE LEANING
TOWARD THE OVERALL DRIER NAM QPF, BUT THIS MODEL STILL BRINGS
SIGNIFICANT QPF TO THE NORTHERN BLUE MOUNTAINS AFTER A BRIEF
PERIOD OF MODERATE PRECIP MAINLY TO THE WASHINGTON PORTION OF THE
CWA. /JBONK
&&
.PREV DISCUSSION... /ISSUED 300 AM PST SAT NOV 21 2009/
SHORT TERM...TODAY THROUGH SUNDAY...THE BACK SIDE OF A VERY SHARP
AND DEEP UPPER TROUGH CONTINUES TO MOVE ACROSS THE REGION EARLY THIS
MORNING. THE ENERGY DIGGING DOWN THE BACK SIDE OF THE TROUGH IS
KEEPING A FEW SHOWERS...MOSTLY SNOW...GOING OVER PORTIONS OF THE
AREA...ESPECIALLY ALONG AND JUST EAST OF THE CASCADES. AS THIS
TROUGH EXITS THE AREA THIS MORNING SHOULD SEE THESE SHOWERS WIND
DOWN FURTHER...TO MAINLY A FEW ALONG THE CASCADE CREST. A POTENT
SYSTEM IS CURRENTLY TAKING SHAPE OUT ALONG 150W THIS MORNING. THIS
SYSTEM WILL SWING ACROSS THE REGION LATE TONIGHT AND ON SUNDAY.
THERE IS A CHANCE THAT A SURFACE LOW WILL FORM OFF THE NORTHWEST
OREGON COAST LATE TONIGHT AND THEN MOVE EAST ACROSS WASHINGTON STATE
SUNDAY. THERE IS SOME UNCERTAINTY AS TO THE TRACK OF THIS SURFACE
LOW AS SOME DATA POINTS TO IT SWINGING MORE NORTHEASTWARD THROUGH
WESTERN WASHINGTON INTO BRITISH COLUMBIA. THE TRACK OF THIS SURFACE
LOW WILL DETERMINE THE WEATHER CONDITIONS OVER OUR AREA SUNDAY. IF
THE LOW MOVES INTO THE INTERIOR NORTHWEST AS SOME DATA SUGGESTS THEN
WE WOULD SEE STRONG WINDS OVER CENTRAL OREGON...THE BLUE MOUNTAIN
FOOTHILLS...THE GRANDE RONDE VALLEY AND WALLOWA COUNTY. ALSO THERE
WOULD BE SIGNIFICANT PRECIP OVER MANY AREAS AS THE SYSTEM MOVES
THROUGH. ALSO THERE WOULD BE WESTERLY UPSLOPE FLOW BEHIND THE
SYSTEM. A QUICK CUT OFF OF PRECIP IN THE LEE OF THE CASCADES DUE TO
THE WEST FLOW WOULD LIMIT SNOW ALONG THE CASCADE EAST SLOPE ZONES.
MEANWHILE THE UPSLOPE FLOW INTO THE BLUE MOUNTAINS WOULD ALLOW
CONSIDERABLE POST SYSTEM SNOW ACCUMULATIONS. THE ALTERNATE SOLUTION
REDUCES THE WIND RISK ACROSS THE AREA...AND ALTERS THE FOCUS OF
PRECIP AND SNOW ACCUMULATIONS AWAY FROM THE BLUES AND TO THE
WASHINGTON CASCADE EAST SLOPES. AT THIS TIME WILL SIDE WITH THE
SOLUTIONS (NAM AND EUROPEAN) THAT ADVERTISE THE SURFACE LOW TRACKING
EAST INTO THE INTERIOR NORTHWEST. AS SUCH WILL ISSUE WIND AND WINTER
STORM WATCHES FOR THE AREAS MENTIONED ABOVE THAT WOULD BE AFFECTED
BY THE EASTERLY TRACK. WILL ONLY GO WITH WATCHES THOUGH DUE TO THE
CONTINUED UNCERTAINTY. 90
LONG TERM...SUNDAY NIGHT THROUGH NEXT SATURDAY...A WEATHER SYSTEM
WILL BE DEPARTING THE FORECAST AREA SUNDAY NIGHT WHILE AN UPPER
RIDGE BUILDS OVER THE REGION. THIS WILL PUSH MOST OF THE MOISTURE
WITH ANY NEW SYSTEMS THAT TRY TO MOVE INTO THE PACIFIC NORTHWEST UP
INTO SW CANADA AND EXTREME NW WASHINGTON. AS A RESULT OUR FORECAST
AREA WILL SEE MOSTLY DRY CONDITIONS WITH JUST ISOLATED TO SCATTERED
SHOWERS IN THE MOUNTAINS. THIS SCENARIO WILL PERSIST THROUGH
THURSDAY. THERE WILL BE PATCHY FOG DEVELOPMENT IN THE USUAL LOW
AREAS OF THE LOWER COLUMBIA BASIN AND ESPECIALLY ALONG THE LARGER
RIVERS SUCH AS THE COLUMBIA...YAKIMA AND SNAKE RIVERS. A PACIFIC
TROUGH WILL THEN MOVE INTO THE REGION AGAIN ON FRIDAY AND FRIDAY
NIGHT BRINGING ANOTHER CHANCE OF RAIN AND MOUNTAIN SNOW. THERE IS
CONSIDERABLE MODEL DIFFERENCES THAT FAR OUT IN THE EXTENDED PERIOD
SO WILL NOT MAKE ANY CHANGES TO THE CURRENT FORECAST WHICH IS
ALREADY REPRESENTATIVE FOR THAT SYSTEM. 88
AVIATION...12Z TAFS...VFR CONDITIONS WILL PREVAIL IN MOST AREAS
THROUGH TODAY WITH SCATTERED TO BROKEN MID LEVEL CEILINGS. ANOTHER
PACIFIC WEATHER SYSTEM WILL MOVE INTO THE AREA LATE TONIGHT AND
EARLY SUNDAY MORNING WITH RAIN AND MOUNTAIN SNOW INCREASING. THIS
WILL CAUSE AREAS OF MVFR TO IFR CONDITIONS WITH POSSIBLY EVEN LIFR
OR VLIFR CONDITIONS IN LOCAL AREAS WITH SNOW OR FOG...ESPECIALLY
NEAR ANY MOUNTAIN RANGES OR OVER THE CENTRAL OREGON PLATEAUS NEAR
TAF SITE KRDM. WINDS OF 10 TO 20 KTS WITH GUSTS TO 30 KTS FROM THE
SOUTHWEST WILL BE COMMON IN ALL AREAS TODAY. HOWEVER THE WINDS WILL
INCREASE OVERNIGHT TONIGHT AS PRESSURE GRADIENTS TIGHTEN UP AHEAD OF
THE NEXT WEATHER SYSTEM. DURING THAT TIME WINDS ARE EXPECTED TO
INCREASE TO AT LEAST 20 TO 30 KTS WITH GUSTS TO 40 KTS OR POSSIBLY
EVEN HIGHER INTO SUNDAY. 88
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 48 37 47 31 / 10 80 70 10
ALW 49 38 48 32 / 10 80 70 10
PSC 52 36 51 30 / 10 80 50 10
YKM 49 32 48 29 / 10 80 40 10
HRI 50 35 49 29 / 10 80 50 10
ELN 46 32 45 26 / 20 80 50 10
RDM 44 34 45 24 / 20 70 40 10
LGD 43 36 43 22 / 20 80 80 20
GCD 42 33 42 21 / 10 70 60 10
DLS 50 37 49 32 / 20 80 40 20
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON FOR
ORZ501-504.
WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR ORZ502.
HIGH WIND WATCH FROM THIS EVENING THROUGH SUNDAY MORNING FOR
ORZ042-043.
HIGH WIND WATCH FROM 7 PM PST THIS EVENING THROUGH SUNDAY
MORNING FOR ORZ049-050.
WA...HIGH WIND WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON FOR
WAZ029.
WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR WAZ030.
&&
THREAT INDEX
TODAY : RED
SUNDAY : RED
MONDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
87
000
FXUS65 KBOI 211638
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
938 AM MST SAT NOV 21 2009
.DISCUSSION...UPDATED FORECASTS. COLD FRONTAL COOLING WILL LIMIT
HIGHS TODAY TO THE 30S TO MID 40S...AND MORNING SOUNDING INDICATES
44 FOR A HIGH AT BOISE. VALLEY SHOWERS LAST EVENING SCRUBBED
DUST/DIRT OUT WITH REPORTS FROM MARSING TO MIDDLETON TO EMMETT
CONSISTENT WITH YESTERDDAY/S BLOWING DUST REPORTS AND MULTI SENSOR
PRECIPITATION ESTIMATES THOSE LOCATIONS AS WELL. COLD FRONT
BRINGING IN CLEANER AIR IN AS WELL. ABOUT 7C/KM LAPSE RATES BELOW
550 MBS AIDING FAST MOVING SNOW SHOWERS THROUGH THE BOISE
MOUNTAINS AS OF 9 AM. DRY ACROSS SE OREGON AND VALLEYS OF SW IDAHO
TODAY WITH DIMINISHING SNOW SHOWERS IN THE CENTRAL MOUNTAINS. NEXT
SYSTEM IS PROGGED 3HRS LATER IN THE SREF...6 NAM/GFS..AND 9 HRS
LATER IN 00Z EC. SO HAVE ADJUSTED TIMING BY 3 HRS FOR NOW. THIS
ALLOWS MINS TO BE A COUPLE DEGREES COLDER AND SUPPORTS UP TO AN
INCH OF WET SNOW ACCUMULATION ON GRASSY/GROUND AREAS ON THE NORTH
HALF OF THE TREASURE VALLEY ZONES. SOME ROADWAYS MAY GET A
DUSTING. SNOW ENDS IN THE VALLEYS TOWARDS NOON AND TEMPERATURES
WARM IN TO THE UPPER 30S BY NOON SUNDAY...WHILE MODERATE TO HEAVY
SNOW IS EXPECTED TO LINGER IN THE WEST CENTRAL AND BOISE MOUNTAINS
THROUGH EARLY TO MID-AFTERNOON. WILL UPDATE WX STORY AS WELL FOR
THIS NEW TIMING AND STILL EXPECTED AMOUNTS FROM LIGHT IN THE SRN
VALLEYS AND HARNEY/MALHEUR COUNTIES TO MODERATE...BKE/IDAHO
CITY/FAIRFIELD TO MODERATE OR HEAVY...ZONE 11/13 MOUNTAINS.
&&
.AVIATION...BRIEF IFR CONDITIONS WILL ACCOMPANY WIDELY SCATTERED
SNOW SHOWERS IN THE BOISE AND WEST CENTRAL MTNS TODAY. LOWER
VALLEYS OF SW IDAHO AND ALL OF SE OREGON WILL BE VFR. ANOTHER
STORM BRINGS IFR CONDITIONS TO SE OREGON AFTER 06Z SUNDAY MORNING
AND AFTER 10Z IN SW IDAHO. EXPECT A 4-6 HOUR PERIOD OF IFR
CONDITIONS AT KBOI WITH BRIEF PERIODS OF MODERATE SNOW POSSIBLE.
IFR CONDITIONS CONTINUE IN THE SW IDAHO MTNS AND WESTERN MAGIC
VALLEY THROUGH SUNDAY AFTERNOON. STRONG WESTERLY WINDS ALOFT ON
SUNDAY OF 40-60 KTS.
&&
.PREV DISCUSSION...
SHORT TERM...TODAY THROUGH SUNDAY...WEAK SYSTEM EXITING THE
FORECAST AREA AT THIS TIME WITH LINGERING SCATTERED RAIN AND SNOW
SHOWERS. THESE CURRENT CONVECTIVE SHOWERS ASSOCIATED WITH PASSAGE OF
THE UPPER LEVEL TROUGH. A DECENT WEATHER DAY TODAY WITH A DRIER PUSH
OF WEST TO NORTHWEST FLOW AND SEASONAL TEMPS AHEAD OF A MORE POTENT
PACIFIC SYSTEM FOR TONIGHT AND SUNDAY. THIS NEXT SYSTEM IS FAST
MOVING...EMBEDDED WITHIN A POWERFUL JETSTREAM FLOW. YET...QPF LOOKS
RATHER SUBSTANTIAL IN NORTHERN AREAS AND WITH WEST FLOW...OROGRAPHIC
ENHANCEMENT WILL AID STORM TOTAL SNOW ACCUMULATIONS. TIMING INTO
BAKER COUNTY OREGON TONIGHT ABOUT 03Z WHICH IS ABOUT 3 HOURS EARLIER
THEN START TIME OVER THE IDAHO ZONES. OVERALL DURATION TO EVENT
SHOULD NOT LAST PAST MID AFTERNOON SUNDAY WITH THE EXCEPTION OF A
FEW LINGERING SNOW SHOWERS. MAIN IMPACTS WITH TONIGHTS STORM
EXPECTED TO BE MODERATE TO LOCALLY HEAVY SNOWFALL AND POOR
VISIBILITY ON NORTH SOUTH RURAL ROADS. TEMPERATURES EXPECTED TO TURN
SHARPLY COLDER NORTH OF THE JET STREAM WHICH WILL PRODUCE A LESS
DENSE SNOW THAN IS EXPECTED IN THE SOUTHERN ZONES. THIS IN TURN
SHOULD DROP VISIBILITY TO LESS THAN ONE HALF MILE AT TIMES. HAVE
OPTED TO ISSUE A WINTER STORM WATCH FOR THE NORTHERN MOUNTAIN ZONES
AND LET DAY CREW MAKE FINAL DECISION OF SPECIFIC WINTER HIGHLIGHTS
JUST BEFORE THE EVENT UNFOLDS.
LONG TERM..SUNDAY NIGHT THROUGH SATURDAY...SNOW SHOWERS WILL
PERSIST ACROSS SW IDAHO TERRAIN...BEFORE TAPERING OFF BY MONDAY
EVENING. TEMPERATURES WILL QUICKLY REBOUND TO ABOVE NORMAL VALUES ON
TUESDAY AS AN UPPER LEVEL RIDGE BUILDS OVER NRN CALIFORNIA/NEVADA.
BY WEDNESDAY...A STRENGTHENING SURFACE INVERSION WILL KEEP AFTERNOON
MIXING TO A MINIMUM - FOR COOLER VALLEY HIGHS. A SIMILAR ISSUE
POSSIBLE ON THURSDAY...BUT CURRENT FORECAST RELIES ON LOW-LEVEL WARM
ADVECTION /AHEAD OF AN APPROACHING TROUGH/ TO INCREASE MIXING AND
KEEP TEMPERATURES ABOVE NORMAL. UPPER TROUGH PROGGED TO MOVE INTO
THE REGION EARLY FRIDAY...BUT MODELS VARY SUBSTANTIALLY IN LOCATION.
THEREFORE HAVE REMAINED CONSERVATIVE WITH NEAR CLIMO POPS /FRIDAY
AND SATURDAY/ DUE TO UNCERTAINTY.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR IDZ011-IDZ013.
OR...WINTER STORM WATCH FROM THIS EVENING THROUGH SUNDAY AFTERNOON
FOR ORZ062.
&&
$$
WEATHER.GOV/BOISE
DISCUSSION...VM
AVIATION.....DG
PREV SHORT TERM...GS
PREV LONG TERM....MT/JT
000
FXUS66 KPQR 211634
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
833 AM PST SAT NOV 21 2009
.SYNOPSIS...A WARM FRONT WILL APPROACH THE OREGON COAST THIS
AFTERNOON THEN PUSH INLAND THIS EVENING. A COLD FRONT WILL QUICKLY
FOLLOW TONIGHT AS A SURFACE LOW PRESSURE SYSTEM MOVES INLAND NEAR THE
WA OREGON BORDER. A WEAK RIDGE OF HIGH PRESSURE WILL FOLLOW SUN
AFTERNOON AND NIGHT...BEFORE THE NEXT FRONTAL SYSTEM ARRIVES MON.
&&
.SHORT TERM...LATEST MODEL RUNS CONTINUE TO EXHIBIT DIFFERENCES IN
TRACK OF THE SURFACE LOW COMING IN TONIGHT. UPPER FEATURES APPEAR
PRETTY WELL AGREED ON...WITH A STRONG SHORTWAVE MOVING ACROSS THE
FORECAST AREA TONIGHT...DIGGING TO THE ESE. GIVEN THE TRACT OF THE
UPPER VORT MAX AND THE NEGATIVE TILT OF THE UPPER TROUGH...CONTINUE
TO PREFER A MORE SOUTHERLY TRACK OF THE SURFACE LOW...AS SUCH PREFER
THE 00Z RUN OF THE ECMWF WHICH TAKES A SURFACE LOW E ROUGHLY ACROSS
KKLS AT 12Z SUN. TIMING OF THE COLD FRONT IN ALL MODELS INDICATES
FRONTAL PASSAGE ON THE COAST NOT UNTIL SOMETIME TONIGHT. GIVEN THE
CONTINUED UNCERTAINTIES IN THE MODELS...FOR NOW WILL LEAVE HEADLINE
AS A HIGH WIND WATCH FOR THE N AND CENTRAL OREGON COAST...BUT LIMIT
IT TO TONIGHT PERIOD. WINDS INLAND LOOK GUSTY WITH AND BEHIND THE
FRONT AS THERE ARE STRONG PRESSURE RISES BEHIND THE FRONT. AT THIS
TIME THOUGH...BEST GUESS IS FOR WINDS TO BE BELOW WARNING
CRITERIA...ALTHOUGH WILLAMETTE VALLEY MAY APPROACH ADVISORY LEVELS
LATE TONIGHT.
DOPPLER RADAR CONTINUES TO SHOW SHOWERS SPREADING OVER MOST OF THE
FORECAST AREA THIS MORNING AS WESTERLY FLOW ALOFT FOLLOWS THE UPPER
TROUGH. WITH UPPER RIDGING LATER TODAY...AND LOW LEVEL FLOW BACKING
MORE TO THE S...SHOULD SEE SHOWERS DROP OFF TODAY. OVERNIGHT SNOWFALL
AMOUNTS IN THE CASCADES SINCE LAST EVENING HAVE RANGED FROM ROUGHLY 4
TO 9 INCHES. FOR NOW WILL HANG ONTO THE SNOW ADVISORY FOR THE N
OREGON AND S WA CASCADES TODAY...ALTHOUGH WILL LIKELY SEE A
SIGNIFICANT DROPOFF IN SNOWFALL LATER THIS MORNING. WILL CONTINUE
THE WINTER STORM WARNING FOR THE CASCADES AS MOISTURE...STRENGTH OF
THE FRONT AND THE POST FRONTAL FLOW ALL FAVOR SIGNIFICANT SNOWFALL
LATER TONIGHT AND SUN.
CURRENT MODEL RUNS INDICATE BEST CHANCES FOR PRECIPITATION MONDAY
WILL SHIFT N INTO WA WITH WARM FRONT OVERRUNNING. THE UPPER RIDGE
HOLDS COLD FRONT AT BAY UNTIL MON NIGHT. LIKENS
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...WEAK HIGH PRES
BUILDS OVER THE FORECAST AREA MON NIGHT. MODELS SHOW A WEAK SYSTEM
APPROACH THE COAST EARLY TUE...BUT IT TRACKS FURTHER NORTH AND
LIGHTLY BRUSHES THE FAR NORTHWEST CORNER OF THE CWA. THIS RIDGE IS
MORE PERSISTENT THAN PREVIOUS MODEL RUNS SUGGESTED. IT MANAGES TO
DELAY THE ARRIVAL OF A SECOND SYSTEM THROUGH THUR. BY MID NEXT
WEEK...MODELS DISAGREE ON THE SOLUTION FOR THE WEEKEND. GFS MODEL
RUNS ARE INCONSISTENT...THE 06Z RUN HELD BACK ON PRECIP THROUGH THURS
NIGHT BUT THE CURRENT RUN SHOWS RAIN EXTENDING TO THE CASCADES THURS
NIGHT. SO FAR...MODELS SUGGEST A FAIRLY NICE WEEKEND AS ANOTHER UPPER
HIGH PRES TEMPORARILY SETS UP OVER THE PAC NW. LRAMIREZ
&&
.AVIATION...LITTLE CHANGE IN OVERALL CONDITIONS THIS MORNING.
PREDOMINATELY VFR WITH SCATTERED SHOWERS...WHICH MAY BRING VERY
BRIEF MVFR CIGS. CONDITIONS REMAIN VFR THROUGH TODAY...THOUGH WILL
SEE INCREASING MVFR ALONG THE COAST AFTER 20Z AS WARM FRONT SWINGS
ACROSS THE REGION. COLD FRONT TONIGHT WILL BRING INCREASING MVFR
AFTER 04Z...AND INCREASING SOUTHERLY WINDS.
KPDX AND APPROACHES...VFR CONDITIONS THROUGH 05Z...THEN INCREASING
MVFR CIGS AS COLD FRONT APPROACHES. WATCH FOR POTENTIAL OF LOW LEVEL
WIND SHEAR BETWEEN 00Z AND 06Z TONIGHT AS WILL SEE INCREASING SOUTH
WINDS ALOFT...BLOWING OVER THE LOW LEVEL EASTERLY FLOW COMING FROM
GORGE.ROCKEY/WOLFE
&&
.MARINE...NOT MUCH CHANGE. CONDITIONS WILL DETERIORATE LATER TODAY
AS WARM FRONT LIFTS ACROSS THE REGION. THIS WILL BRING GALE FORCE
SOUTH WINDS. HOWEVER...STRONG WINDS ARRIVE TONIGHT AS RATHER STRONG
LOW PRES PASSES ACROSS THE N OREGON COASTAL WATERS. STORM WARNING
FOR THE COASTAL WATERS FOR TONIGHT. WINDS TURN MORE W TO NW ON
SUNDAY AND BEGIN EASING. SEAS TONIGHT LIKELY TO PEAK IN THE 20 TO 25
FT RANGE...BUT WILL DROP QUICKLY ON SUN.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
WA/OR...GALE WARNING FOR COASTAL WATERS FROM CAPE SHOALWATER TO
FLORENCE FOR THIS AFTERNOON.
STORM WARNING FOR COASTAL WATERS FROM CAPE SHOALWATER TO
FLORENCE FOR TONIGHT.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR CONDITIONS
THROUGH SUN.
SNOW ADVISORY FOR THE SOUTH WASHINGTON AND NORTH OREGON
CASCADES THROUGH 4 PM.
WINTER STORM WARNING FOR THE S WA AND N AND CENTRAL OREGON
CASCADES TONIGHT AND SUNDAY.
HIGH WIND WATCH FOR THE NORTHERN AND CENTRAL OREGON COAST
TONIGHT.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS66 KMFR 211205
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
405 AM PST SAT NOV 21 2009
.DISCUSSION...A FEW SHOWERS WILL LINGER ACROSS THE HIGHER TERRAIN
OF THE FORECAST AREA THIS MORNING BUT THE TREND IS FOR BRIEF
DRYING THIS AFTERNOON. BY EARLY EVENING ANOTHER PACIFIC FRONT WILL
MOVE INTO THE COASTAL WATERS. FIRST THE WARM FRONT WILL BRING
GUSTY SOUTH WINDS TO THE COAST TONIGHT. BOTH THE NAM AND GFS SHOW
BOUNDARY LAYER WINDS TO BE IN THE 40 TO 50 MPH RANGE. AS A RESULT
HAVE ISSUED A HIGH WIND WATCH AT THE COAST. THE STRONGEST WINDS
SHOULD OCCUR BETWEEN 10PM AND MIDNIGHT TONIGHT. FARTHER EAST
SOUTHWEST WINDS WILL ALSO PICK UP AHEAD OF THE FRONT. PART OF
HIGHWAY 31 RUNNING FROM PAISLEY TO SUMMER LAKE IN LAKE COUNTY IS
EXPECTED TO SEE ANOTHER ROUND OF GUSTY WINDS AND WIND ADVISORY MAY
BE NEEDED LATER. GUIDANCE ALSO INDICATES INCREASING WINDS IN THE
SHASTA VALLEY THIS EVENING ALTHOUGH WIND DIRECTION DOES NOT APPEAR
AS CONDUCIVE TO THE SPEED REACHING WARNING CRITERIA.
THE COLD FRONT WILL MOVE INTO SOUTHWEST OREGON THIS EVENING WITH
PRECIPITATION SPREADING INTO THE ROGUE VALLEY IN THE EARLY
EVENING. STEADY PRECIPITATION IS EXPECTED TO BE OVERNIGHT TONIGHT
AND THROUGH SUNDAY MORNING. SOUTHERLY WIND AHEAD OF THE FRONT
COULD DELAY COLD AIR FROM FILTERING INTO KLAMATH FALLS BUT BY LATE
TONIGHT THE FRONT IS EXPECTED TO BRING COLD AIR INTO THE EAST
SIDE. IF THE CURRENT QPF FORECAST HOLDS...WE MAY NEED A SNOW
ADVISORY FOR NORTHERN KLAMATH COUNTY FROM DIAMOND LAKE JUNCTION
NORTH THROUGH CHEMULT. BY SUNDAY AFTERNOON PRECIPITATION SHOULD
TAPER OFF TO SHOWERS AND BE CONFINED MAINLY IN UPSLOPE AREA AND
HIGHER TERRAIN.
THE LATEST GFS AND ECMWF CONTINUES WITH THE DRYING TREND FOR MOST
OF NEXT WEEK AS THE STORM TRACK SHIFTS NORTH. THE ECMWF BRINGS THE
NEXT COLD FRONT INLAND ON THANKSGIVING BUT THE GFS HOLDS THE FRONT
OFFSHORE BEFORE BRINGING THE FRONT INLAND DURING THAT NIGHT. HAVE
INTRODUCED A CHANCE POPS FOR THANKSGIVING DAY BUT CONFIDENCE ON
TIMING IS NOT VERY HIGH.
&&
.AVIATION...WIDESPREAD MVFR AT THE COAST THIS EVENING THROUGH
TONIGHT IN FREQUENT MODERATE RAIN. WINDS ALONG THE COAST WILL ALSO
BE VERY STRONG OVERNIGHT WITH LLWS POSSIBLE. MVFR CIGS AND VIS
SPREAD INLAND AND ARE MORE LIKELY AFTER 06Z TONIGHT. HIGHER MOUNTAINS
WILL BE OBSCURED OVERNIGHT.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WATCH FROM THIS AFTERNOON THROUGH LATE TONIGHT FOR
ORZ021-ORZ022.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS FROM 10 AM
THIS MORNING TO 1 PM PST THIS AFTERNOON FOR PZZ350-PZZ356-
PZZ370-PZZ376.
GALE WARNING FROM 1 PM THIS AFTERNOON TO 4 AM PST SUNDAY FOR
PZZ356-PZZ376.
HAZARDOUS SEAS WARNING UNTIL 4 PM PST SUNDAY FOR PZZ350-PZZ356-
PZZ370-PZZ376.
STORM WARNING FROM 4 PM THIS AFTERNOON TO 4 AM PST SUNDAY FOR
PZZ350-PZZ370.
GALE WARNING FROM 1 PM TO 4 PM PST THIS AFTERNOON FOR PZZ350-
PZZ370.
$$
08/99/99
000
FXUS66 KPDT 211103
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
300 AM PST SAT NOV 21 2009
.SHORT TERM...TODAY THROUGH SUNDAY...THE BACK SIDE OF A VERY SHARP
AND DEEP UPPER TROUGH CONTINUES TO MOVE ACROSS THE REGION EARLY THIS
MORNING. THE ENERGY DIGGING DOWN THE BACK SIDE OF THE TROUGH IS
KEEPING A FEW SHOWERS...MOSTLY SNOW...GOING OVER PORTIONS OF THE
AREA...ESPECIALLY ALONG AND JUST EAST OF THE CASCADES. AS THIS
TROUGH EXITS THE AREA THIS MORNING SHOULD SEE THESE SHOWERS WIND
DOWN FURTHER...TO MAINLY A FEW ALONG THE CASCADE CREST. A POTENT
SYSTEM IS CURRENTLY TAKING SHAPE OUT ALONG 150W THIS MORNING. THIS
SYSTEM WILL SWING ACROSS THE REGION LATE TONIGHT AND ON SUNDAY.
THERE IS A CHANCE THAT A SURFACE LOW WILL FORM OFF THE NORTHWEST
OREGON COAST LATE TONIGHT AND THEN MOVE EAST ACROSS WASHINGTON STATE
SUNDAY. THERE IS SOME UNCERTAINTY AS TO THE TRACK OF THIS SURFACE
LOW AS SOME DATA POINTS TO IT SWINGING MORE NORTHEASTWARD THROUGH
WESTERN WASHINGTON INTO BRITISH COLUMBIA. THE TRACK OF THIS SURFACE
LOW WILL DETERMINE THE WEATHER CONDITIONS OVER OUR AREA SUNDAY. IF
THE LOW MOVES INTO THE INTERIOR NORTHWEST AS SOME DATA SUGGESTS THEN
WE WOULD SEE STRONG WINDS OVER CENTRAL OREGON...THE BLUE MOUNTAIN
FOOTHILLS...THE GRANDE RONDE VALLEY AND WALLOWA COUNTY. ALSO THERE
WOULD BE SIGNIFICANT PRECIP OVER MANY AREAS AS THE SYSTEM MOVES
THROUGH. ALSO THERE WOULD BE WESTERLY UPSLOPE FLOW BEHIND THE
SYSTEM. A QUICK CUT OFF OF PRECIP IN THE LEE OF THE CASCADES DUE TO
THE WEST FLOW WOULD LIMIT SNOW ALONG THE CASCADE EAST SLOPE ZONES.
MEANWHILE THE UPSLOPE FLOW INTO THE BLUE MOUNTAINS WOULD ALLOW
CONSIDERABLE POST SYSTEM SNOW ACCUMULATIONS. THE ALTERNATE SOLUTION
REDUCES THE WIND RISK ACROSS THE AREA...AND ALTERS THE FOCUS OF
PRECIP AND SNOW ACCUMULATIONS AWAY FROM THE BLUES AND TO THE
WASHINGTON CASCADE EAST SLOPES. AT THIS TIME WILL SIDE WITH THE
SOLUTIONS (NAM AND EUROPEAN) THAT ADVERTISE THE SURFACE LOW TRACKING
EAST INTO THE INTERIOR NORTHWEST. AS SUCH WILL ISSUE WIND AND WINTER
STORM WATCHES FOR THE AREAS MENTIONED ABOVE THAT WOULD BE AFFECTED
BY THE EASTERLY TRACK. WILL ONLY GO WITH WATCHES THOUGH DUE TO THE
CONTINUED UNCERTAINTY. 90
.LONG TERM...SUNDAY NIGHT THROUGH NEXT SATURDAY...A WEATHER SYSTEM
WILL BE DEPARTING THE FORECAST AREA SUNDAY NIGHT WHILE AN UPPER
RIDGE BUILDS OVER THE REGION. THIS WILL PUSH MOST OF THE MOISTURE
WITH ANY NEW SYSTEMS THAT TRY TO MOVE INTO THE PACIFIC NORTHWEST UP
INTO SW CANADA AND EXTREME NW WASHINGTON. AS A RESULT OUR FORECAST
AREA WILL SEE MOSTLY DRY CONDITIONS WITH JUST ISOLATED TO SCATTERED
SHOWERS IN THE MOUNTAINS. THIS SCENARIO WILL PERSIST THROUGH
THURSDAY. THERE WILL BE PATCHY FOG DEVELOPMENT IN THE USUAL LOW
AREAS OF THE LOWER COLUMBIA BASIN AND ESPECIALLY ALONG THE LARGER
RIVERS SUCH AS THE COLUMBIA...YAKIMA AND SNAKE RIVERS. A PACIFIC
TROUGH WILL THEN MOVE INTO THE REGION AGAIN ON FRIDAY AND FRIDAY
NIGHT BRINGING ANOTHER CHANCE OF RAIN AND MOUNTAIN SNOW. THERE IS
CONSIDERABLE MODEL DIFFERENCES THAT FAR OUT IN THE EXTENDED PERIOD
SO WILL NOT MAKE ANY CHANGES TO THE CURRENT FORECAST WHICH IS
ALREADY REPRESENTATIVE FOR THAT SYSTEM. 88
&&
.AVIATION...12Z TAFS...VFR CONDITIONS WILL PREVAIL IN MOST AREAS
THROUGH TODAY WITH SCATTERED TO BROKEN MID LEVEL CEILINGS. ANOTHER
PACIFIC WEATHER SYSTEM WILL MOVE INTO THE AREA LATE TONIGHT AND
EARLY SUNDAY MORNING WITH RAIN AND MOUNTAIN SNOW INCREASING. THIS
WILL CAUSE AREAS OF MVFR TO IFR CONDITIONS WITH POSSIBLY EVEN LIFR
OR VLIFR CONDITIONS IN LOCAL AREAS WITH SNOW OR FOG...ESPECIALLY
NEAR ANY MOUNTAIN RANGES OR OVER THE CENTRAL OREGON PLATEAUS NEAR
TAF SITE KRDM. WINDS OF 10 TO 20 KTS WITH GUSTS TO 30 KTS FROM THE
SOUTHWEST WILL BE COMMON IN ALL AREAS TODAY. HOWEVER THE WINDS WILL
INCREASE OVERNIGHT TONIGHT AS PRESSURE GRADIENTS TIGHTEN UP AHEAD OF
THE NEXT WEATHER SYSTEM. DURING THAT TIME WINDS ARE EXPECTED TO
INCREASE TO AT LEAST 20 TO 30 KTS WITH GUSTS TO 40 KTS OR POSSIBLY
EVEN HIGHER INTO SUNDAY. 88
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 48 37 47 31 / 10 80 70 10
ALW 49 38 48 32 / 10 80 70 10
PSC 52 36 51 30 / 10 80 50 10
YKM 49 32 48 29 / 10 80 40 10
HRI 50 35 49 29 / 10 80 50 10
ELN 46 32 45 26 / 20 80 50 10
RDM 44 34 45 24 / 20 70 40 10
LGD 43 36 43 22 / 20 80 80 20
GCD 42 33 42 21 / 10 70 60 10
DLS 50 37 49 32 / 20 80 40 20
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON FOR
ORZ501-504.
WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR ORZ502.
HIGH WIND WATCH FROM THIS EVENING THROUGH SUNDAY MORNING FOR
ORZ042-043.
HIGH WIND WATCH FROM THIS EVENING THROUGH SUNDAY MORNING FOR
ORZ049-050.
WA...HIGH WIND WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON FOR
WAZ029.
WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR WAZ030.
&&
THREAT INDEX
TODAY : YELLOW
SUNDAY : YELLOW
MONDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
90/88/88
000
FXUS65 KBOI 211037
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
335 AM MST SAT NOV 21 2009
.SHORT TERM...TODAY THROUGH SUNDAY...WEAK SYSTEM EXITING THE
FORECAST AREA AT THIS TIME WITH LINGERING SCATTERED RAIN AND SNOW
SHOWERS. THESE CURRENT CONVECTIVE SHOWERS ASSOCIATED WITH PASSAGE OF
THE UPPER LEVEL TROUGH. A DECENT WEATHER DAY TODAY WITH A DRIER PUSH
OF WEST TO NORTHWEST FLOW AND SEASONAL TEMPS AHEAD OF A MORE POTENT
PACIFIC SYSTEM FOR TONIGHT AND SUNDAY. THIS NEXT SYSTEM IS FAST
MOVING...EMBEDDED WITHIN A POWERFUL JETSTREAM FLOW. YET...QPF LOOKS
RATHER SUBSTANTIAL IN NORTHERN AREAS AND WITH WEST FLOW...OROGRAPHIC
ENHANCEMENT WILL AID STORM TOTAL SNOW ACCUMULATIONS. TIMING INTO
BAKER COUNTY OREGON TONIGHT ABOUT 03Z WHICH IS ABOUT 3 HOURS EARLIER
THEN START TIME OVER THE IDAHO ZONES. OVERALL DURATION TO EVENT
SHOULD NOT LAST PAST MID AFTERNOON SUNDAY WITH THE EXCEPTION OF A
FEW LINGERING SNOW SHOWERS. MAIN IMPACTS WITH TONIGHTS STORM
EXPECTED TO BE MODERATE TO LOCALLY HEAVY SNOWFALL AND POOR
VISIBILITY ON NORTH SOUTH RURAL ROADS. TEMPERATURES EXPECTED TO TURN
SHARPLY COLDER NORTH OF THE JET STREAM WHICH WILL PRODUCE A LESS
DENSE SNOW THAN IS EXPECTED IN THE SOUTHERN ZONES. THIS IN TURN
SHOULD DROP VISIBILITY TO LESS THAN ONE HALF MILE AT TIMES. HAVE
OPTED TO ISSUE A WINTER STORM WATCH FOR THE NORTHERN MOUNTAIN ZONES
AND LET DAY CREW MAKE FINAL DECISION OF SPECIFIC WINTER HIGHLIGHTS
JUST BEFORE THE EVENT UNFOLDS.
.LONG TERM..SUNDAY NIGHT THROUGH SATURDAY...SNOW SHOWERS WILL
PERSIST ACROSS SW IDAHO TERRAIN...BEFORE TAPERING OFF BY MONDAY
EVENING. TEMPERATURES WILL QUICKLY REBOUND TO ABOVE NORMAL VALUES ON
TUESDAY AS AN UPPER LEVEL RIDGE BUILDS OVER NRN CALIFORNIA/NEVADA.
BY WEDNESDAY...A STRENGTHENING SURFACE INVERSION WILL KEEP AFTERNOON
MIXING TO A MINIMUM - FOR COOLER VALLEY HIGHS. A SIMILAR ISSUE
POSSIBLE ON THURSDAY...BUT CURRENT FORECAST RELIES ON LOW-LEVEL WARM
ADVECTION /AHEAD OF AN APPROACHING TROUGH/ TO INCREASE MIXING AND
KEEP TEMPERATURES ABOVE NORMAL. UPPER TROUGH PROGGED TO MOVE INTO
THE REGION EARLY FRIDAY...BUT MODELS VARY SUBSTANTIALLY IN LOCATION.
THEREFORE HAVE REMAINED CONSERVATIVE WITH NEAR CLIMO POPS /FRIDAY
AND SATURDAY/ DUE TO UNCERTAINTY.
&&
.AVIATION...SW IDAHO - IFR SNOW SHOWERS ACROSS HIGHER TERRAIN
/MAINLY W CENTRAL AND BOISE MTNS/ WILL PERSIST THROUGH 21Z. MTNS
WILL BE OBSCURED. VFR RAIN SHOWERS ACROSS THE WRN SNAKE PLAIN /E OF
BOISE/ THROUGH 15Z. LIGHT TO MODERATE SURFACE WINDS - WITH GUSTS TO
25 KTS EAST AND SOUTH OF KMUO. SE OREGON - VFR UNDER BKN-OVC SKIES
OVERNIGHT. LIGHT WINDS.
IFR CONDITIONS WILL RETURN AFTER 06Z TONIGHT...AS ANOTHER STORM
SYSTEM MOVES INTO THE AREA. EXPECT WIDESPREAD IFR SNOW - ALL
ELEVATIONS.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...WINTER STORM WATCH FROM 06Z SUNDAY THROUGH 21Z FOR IDZ011 AND
IDZ013.
OR...WINTER STORM WATCH FROM 03Z SUNDAY THROUGH 18Z FOR ORZ062.
&&
$$
WEATHER.GOV/BOISE
SHORT TERM...GS
LONG TERM....MT/JT
AVIATION.....MT
000
FXUS66 KPQR 211019
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
220 AM PST SAT NOV 21 2009
.SYNOPSIS...A WARM FRONT WILL APPROACH THE OREGON COAST THIS
AFTERNOON THEN PUSH INLAND THIS EVENING. A COLD FRONT WILL QUICKLY
FOLLOW TONIGHT AS A SURFACE LOW PRESSURE SYSTEM MOVES INLAND NEAR
THE WA OREGON BORDER. A WEAK RIDGE OF HIGH PRESSURE WILL FOLLOW SUN
AFTERNOON AND NIGHT...BEFORE THE NEXT FRONTAL SYSTEM ARRIVES MON.
&&
.SHORT TERM...LATEST MODEL RUNS CONTINUE TO EXHIBIT DIFFERENCES IN
TRACK OF THE SURFACE LOW COMING IN TONIGHT. UPPER FEATURES APPEAR
PRETTY WELL AGREED ON...WITH A STRONG SHORTWAVE MOVING ACROSS THE
FORECAST AREA TONIGHT...DIGGING TO THE ESE. GIVEN THE TRACT OF THE
UPPER VORT MAX AND THE NEGATIVE TILT OF THE UPPER TROUGH...CONTINUE
TO PREFER A MORE SOUTHERLY TRACK OF THE SURFACE LOW...AS SUCH PREFER
THE 00Z RUN OF THE ECMWF WHICH TAKES A SURFACE LOW E ROUGHLY ACROSS
KKLS AT 12Z SUN. TIMING OF THE COLD FRONT IN ALL MODELS INDICATES
FRONTAL PASSAGE ON THE COAST NOT UNTIL SOMETIME TONIGHT. GIVEN THE
CONTINUED UNCERTAINIES IN THE MODELS...FOR NOW WILL LEAVE HEADLINE
AS A HIGH WIND WATCH FOR THE N AND CENTRAL OREGON COAST...BUT LIMIT
IT TO TONIGHT PERIOD. WINDS INLAND LOOK GUSTY WITH AND BEHIND THE
FRONT AS THERE ARE STRONG PRESSURE RISES BEHIND THE FRONT. AT THIS
TIME THOUGH...BEST GUESS IS FOR WINDS TO BE BELOW WARNING
CRITERIA...ALTHOUGH WILLAMETTE VALLEY MAY APPROACH ADVISORY LEVELS
LATE TONIGHT.
SHOWERS CONTINUE OVER MOST OF THE FORECAST AREA EARLY THIS MORNING
AS A WESTERLY FLOW ALOFT FOLLOWS THE UPPER TROUGH. WITH UPPER
RIDGING LATER TODAY...AND LOW LEVEL FLOW BACKING MORE TO THE
S...SHOULD SEE SHOWERS DROP OFF TODAY. OVERNIGHT SNOWFALL AMOUNTS IN
THE CASCADES SINCE LAST EVENING HAVE RANGED FROM ROUGHLY 4 TO 9
INCHES. FOR NOW WILL HANG ONTO THE SNOW ADVISORY FOR THE N OREGON
AND S WA CASCADES TODAY...ALTHOUGH WILL LIKELY SEE A SIGNIFICANT
DROPOFF IN SNOWFALL LATER THIS MORNING. WILL UPGRADE THE WATCH
TONIGHT TO A WARNING FOR THE CASCADES AS MOISTURE...STRENGTH OF THE
FRONT AND THE POST FRONTAL FLOW ALL FAVOR SIGNIFICANT SNOWFALL LATER
TONIGHT AND SUN.
WILL BACK OFF ON POPS FOR SUN NIGHT AND MON AS CURRENT MODEL RUNS
INDICATE BEST CHANCES FOR PRECIPITATION WILL SHIFT N INTO WA WITH
BEST WARM FRONT OVERRUNNING...AND THE UPPER RIDGE HOLDS COLD FRONT
AT BAY UNTIL MON NIGHT.
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
WEAK HIGH PRES BUILDS OVER THE FORECAST AREA MON NIGHT. MODELS SHOW
A WEAK SYSTEM APPROACH THE COAST EARLY TUE...BUT IT TRACKS FURTHER
NORTH AND LIGHTLY BRUSHES THE FAR NORTHWEST CORNER OF THE CWA. THIS
RIDGE IS MORE PERSISTENT THAN PREVIOUS MODEL RUNS SUGGESTED. IT
MANAGES TO DELAY THE ARRIVAL OF A SECOND SYSTEM THROUGH THUR. BY MID
NEXT WEEK...MODELS DISAGREE ON THE SOLUTION FOR THE WEEKEND. GFS
MODEL RUNS ARE INCONSISTENT...THE 06Z RUN HELD BACK ON PRECIP
THROUGH THURS NIGHT BUT THE CURRENT RUN SHOWS RAIN EXTENDING TO THE
CASCADES THURS NIGHT. SO FAR...MODELS SUGGEST A FAIRLY NICE WEEKEND
AS ANOTHER UPPER HIGH PRES TEMPORARILY SETS UP OVER THE PAC NW.
LRAMIREZ
&&
.AVIATION...LITTLE CHANGE IN OVERALL CONDITIONS THIS MORNING.
PREDOMINATELY VFR WITH SCATTERED SHOWERS...WHICH MAY BRING VERY
BRIEF MVFR CIGS. CONDITIONS REMAIN VFR THROUGH TODAY...THOUGH WILL
SEE INCREASING MVFR ALONG THE COAST AFTER 20Z AS WARM FRONT SWINGS
ACROSS THE REGION. COLD FRONT TONIGHT WILL BRING INCREASING MVFR
AFTER 04Z...AND INCREASING SOUTHERLY WINDS.
KPDX AND APPROACHES...VFR CONDITIONS THROUGH 05Z...THEN INCREASING
MVFR CIGS AS COLD FRONT APPROACHES. WATCH FOR POTENTIAL OF LOW LEVEL
WIND SHEAR BETWEEN 00Z AND 06Z TONIGHT AS WILL SEE INCREASING SOUTH
WINDS ALOFT...BLOWING OVER THE LOW LEVEL EASTERLY FLOW COMING FROM
GORGE. ROCKEY.
&&
.MARINE...NOT MUCH CHANGE. CONDITIONS WILL DETERIORATE LATER TODAY
AS WARM FRONT LIFTS ACROSS THE REGION. THIS WILL BRING GALE FORCE
SOUTH WINDS. HOWEVER...STRONG WINDS ARRIVE TONIGHT AS RATHER STRONG
LOW PRES PASSES ACROSS THE N OREGON COASTAL WATERS. WILL HOIST STORM
WARNING FOR THE COASTAL WATERS FOR TONIGHT. WINDS TURN MORE W TO NW
ON SUNDAY AND BEGIN EASING. SEAS TONIGHT LIKELY TO PEAK IN THE 20 TO
25 FT RANGE...BUT WILL DROP QUICKLY ON SUN.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
WA/OR...GALE WARNING FOR COASTAL WATERS FROM CAPE SHOALWATER TO
FLORENCE FOR THIS AFTERNOON.
STORM WARNING FOR COASTAL WATERS FROM CAPE SHOALWATER TO
FLORENCE FOR TONIGHT.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBAR BAR CONDITIONS
THROUGH SUN.
SNOW ADVISORY FOR THE SOUTH WASHINGTON AND NORTH OREGON
CASCADES THROUGH 4 PM.
WINTER STORM WARNING FOR THE S WA AND N AND CENTRAL OREGON
CASCADES TONIGHT AND SUNDAY.
HIGH WIND WATCH FOR THE NORTHERN AND CENTRAL OREGON COAST
TONIGHT.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS66 KPDT 210605 AAA
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
955 PM PST FRI NOV 20 2009
UPDATED THE AVIATION DISCUSSION
.UPDATE...THE LATEST RADAR WAS SHOWING THE SHOWERS FROM EARLIER WERE
MOVG EAST OF THE AREA WITH DRIER AIR ADVECTING INTO MOST OF THE
COLUMBIA BASIN. AS A DEPARTING TROUGH OF LOW PRESSURE EXITS THE AREA
OVERNIGHT...CLOUDS AND SOME SHOWERS WILL LINGER ACROSS THE REGION
AND ESPECIALLY IN THE MOUNTAINS WHERE MINOR ACCUMULATIONS OF SNOW
ARE STILL POSSIBLE. OTHER THAN MAKING SOME ADJUSTMENTS TO POPS AND
WEATHER ALONG WITH SKY THE PRESENT SHORT TERM FORECAST APPEARS ON
TRACK FOR NOW.
.AVIATION...VFR CONDITIONS WILL PERSIST UNTIL MORNING UNTIL THE NEXT
STORM SYSTEM EFFECTS THE REGION TOMORROW. AFTER 12Z MVFR CONDITIONS
ARE POSSIBLE AS TAF SITES KYKM...KDLS...KRDM DUE TO LOWERING
CEILINGS AND THEN THE REMAINDER OF THE TAF SITES WILL BE EFFECTED
AFTER 15Z. EARLY TOMORROW NIGHT AFTER 02Z TAF SITES KDLS AND KRDM
MAY EXPERIENCE BRIEF IFR CONDITIONS IN SHOWERS THAT WILL LOWER
CEILINGS.
&&
.PREV DISCUSSION... /ISSUED 415 PM PST FRI NOV 20 2009/
SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT...A FRONT HAS CROSSED
OVER THE CASCADES WITH BREEZY TO WINDY SOUTHERLY WINDS AHEAD OF
IT...PARTICULARLY ABOVE 2000 FEET. HIGHER WINDS ALOFT ARE
OCCASIONALLY MIXING TO THE SURFACE. THE DOWNSLOPING SOUTHEAST WINDS
IN THE FOOTHILLS OF THE BLUES HAVE DRIED OUT THE LOW LEVELS WITH RHS
IN THE TEENS AND 20S. THIS HAS LIMITED PRECIPITATION. AS THE COLD
FRONT MOVES CLOSER EXPECT THE PRECIPITATION TO INCREASE AT ALL
LOCATIONS EXCEPT THE YAKIMA AND KITTITAS VALLEYS THIS EVENING. WINDS
WILL BECOME WEST BEHIND THE FRONT AND DECREASE OVERNIGHT. AN UPPER
LEVEL TROUGH WILL KEEP SHOWERS IN THE NORTHEAST OREGON MOUNTAINS
OVERNIGHT. DRIER NORTHWEST FLOW WILL BE OVER EASTERN WASHINGTON AND
OREGON SATURDAY WITH UPSLOPE SLOPE FLOW KEEPING SHOWERS IN THE
MOUNTAINS. ANOTHER FRONT WILL INCREASE RAIN AND SNOW OVER THE EAST
SLOPES OF THE CASCADES SATURDAY AFTERNOON...AND SPREAD OVER THE REST
OF EASTERN WASHINGTON AND OREGON SATURDAY NIGHT AND SUNDAY. SUNDAY
AFTERNOON THE UPPER LEVEL TROUGH WILL MOVE THROUGH EASTERN
WASHINGTON AND OREGON AND WESTERLY FLOW WILL START RAIN SHADOWING IN
THE LOWER COLOMBIA BASIN AND DESCHUTES PLATEAU. UPPER LEVEL RIDGING
WILL BUILD NEAR THE COAST SUNDAY NIGHT AND STOP THE PRECIPITATION
EXCEPT FOR SLOP OVER PRECIPITATION IN THE CASCADES AND UPSLOPE FLOW
IN NORTHEAST OREGON MOUNTAINS. COONFIELD
LONG TERM...MONDAY THROUGH FRIDAY...MODELS SHOW A MID/UPPER LEVEL
RIDGE OF HIGH PRESSURE MOVE THROUGH THE FORECAST AREA ON MONDAY FOR
MAINLY DRY CONDITIONS EXCEPT ALONG THE EAST SLOPES OF THE CASCADES
WHERE RAIN AND MOUNTAIN SNOW ARE LIKELY. THE RIDGE REMAINS OVER THE
PACIFIC NORTHWEST MONDAY NIGHT THROUGH THANKSGIVING DAY FOR DRY
CONDITIONS...EXCEPT ALONG THE EAS FACING SLOPES OF THE CASCADES
WHERE THERE WILL BE A CHANCE OF SLOP OVER PRECIPITATION FROM THE
WEST SIDE OF WASHINGTON AND OREGON. MODELS HAVE STRONG AGREEMENT IN
SHOWING A MID/UPPER LEVEL TROUGH PUSHING A COLD FRONT AND ASSOCIATED
RAIN THROUGH THE FORECAST AREA THURSDAY NIGHT AND FRIDAY. POLAN
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 36 51 36 50 / 20 10 70 60
ALW 39 52 36 49 / 20 10 70 60
PSC 31 47 36 51 / 10 10 70 40
YKM 28 44 30 50 / 10 20 70 40
HRI 32 50 34 50 / 10 10 70 50
ELN 27 41 27 42 / 10 30 70 40
RDM 22 42 30 45 / 10 30 70 40
LGD 32 41 33 44 / 60 20 80 70
GCD 29 42 29 42 / 40 10 70 60
DLS 36 45 36 52 / 10 30 80 40
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
SATURDAY : GREEN
SUNDAY : GREEN
MONDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
97/99/76
000
FXUS66 KPDT 210520
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
915 PM PST FRI NOV 20 2009
.UPDATE...THE LATEST RADAR WAS SHOWING THE SHOWERS FROM EARLIER WERE
MOVG EAST OF THE AREA WITH DRIER AIR ADVECTING INTO MOST OF THE
COLUMBIA BASIN. AS A DEPARTING TROUGH OF LOW PRESSURE EXITS THE AREA
OVERNIGHT...CLOUDS AND SOME SHOWERS WILL LINGER ACROSS THE REGION
AND ESPECIALLY IN THE MOUNTAINS WHERE MINOR ACCUMULATIONS OF SNOW
ARE STILL POSSIBLE. OTHER THAN MAKING SOME ADJUSTMENTS TO POPS AND
WEATHER ALONG WITH SKY THE PRESENT SHORT TERM FORECAST APPEARS ON
TRACK FOR NOW.
&&
.PREV DISCUSSION... /ISSUED 415 PM PST FRI NOV 20 2009/
SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT...A FRONT HAS CROSSED
OVER THE CASCADES WITH BREEZY TO WINDY SOUTHERLY WINDS AHEAD OF
IT...PARTICULARLY ABOVE 2000 FEET. HIGHER WINDS ALOFT ARE
OCCASIONALLY MIXING TO THE SURFACE. THE DOWNSLOPING SOUTHEAST WINDS
IN THE FOOTHILLS OF THE BLUES HAVE DRIED OUT THE LOW LEVELS WITH RHS
IN THE TEENS AND 20S. THIS HAS LIMITED PRECIPITATION. AS THE COLD
FRONT MOVES CLOSER EXPECT THE PRECIPITATION TO INCREASE AT ALL
LOCATIONS EXCEPT THE YAKIMA AND KITTITAS VALLEYS THIS EVENING. WINDS
WILL BECOME WEST BEHIND THE FRONT AND DECREASE OVERNIGHT. AN UPPER
LEVEL TROUGH WILL KEEP SHOWERS IN THE NORTHEAST OREGON MOUNTAINS
OVERNIGHT. DRIER NORTHWEST FLOW WILL BE OVER EASTERN WASHINGTON AND
OREGON SATURDAY WITH UPSLOPE SLOPE FLOW KEEPING SHOWERS IN THE
MOUNTAINS. ANOTHER FRONT WILL INCREASE RAIN AND SNOW OVER THE EAST
SLOPES OF THE CASCADES SATURDAY AFTERNOON...AND SPREAD OVER THE REST
OF EASTERN WASHINGTON AND OREGON SATURDAY NIGHT AND SUNDAY. SUNDAY
AFTERNOON THE UPPER LEVEL TROUGH WILL MOVE THROUGH EASTERN
WASHINGTON AND OREGON AND WESTERLY FLOW WILL START RAIN SHADOWING IN
THE LOWER COLOMBIA BASIN AND DESCHUTES PLATEAU. UPPER LEVEL RIDGING
WILL BUILD NEAR THE COAST SUNDAY NIGHT AND STOP THE PRECIPITATION
EXCEPT FOR SLOP OVER PRECIPITATION IN THE CASCADES AND UPSLOPE FLOW
IN NORTHEAST OREGON MOUNTAINS. COONFIELD
LONG TERM...MONDAY THROUGH FRIDAY...MODELS SHOW A MID/UPPER LEVEL
RIDGE OF HIGH PRESSURE MOVE THROUGH THE FORECAST AREA ON MONDAY FOR
MAINLY DRY CONDITIONS EXCEPT ALONG THE EAST SLOPES OF THE CASCADES
WHERE RAIN AND MOUNTAIN SNOW ARE LIKELY. THE RIDGE REMAINS OVER THE
PACIFIC NORTHWEST MONDAY NIGHT THROUGH THANKSGIVING DAY FOR DRY
CONDITIONS...EXCEPT ALONG THE EAS FACING SLOPES OF THE CASCADES
WHERE THERE WILL BE A CHANCE OF SLOP OVER PRECIPITATION FROM THE
WEST SIDE OF WASHINGTON AND OREGON. MODELS HAVE STRONG AGREEMENT IN
SHOWING A MID/UPPER LEVEL TROUGH PUSHING A COLD FRONT AND ASSOCIATED
RAIN THROUGH THE FORECAST AREA THURSDAY NIGHT AND FRIDAY. POLAN
AVIATION...00Z TAFS...VFR CONDITIONS WILL PREVAIL FOR THE NEXT 24
HOURS. AREAS OF RAIN AND MOUNTAIN SNOW WILL CONTINUE FOR SEVERAL
MORE HOURS IN NORTHEAST OREGON AND SOUTHEAST WASHINGTON DUE TO A
COLD FRONT MOVING THROUGH. CONDITIONS AT KPDT AND KALW WILL IMPROVE
AFTER BY 05Z THIS EVENING. OCCASIONAL MVFR CONDITIONS MAY OCCUR
ALONG THE AVIATION ROUTE OVER THE BLUE MOUNTAINS UNTIL 21/07Z WHEN
CONDITIONS SHOULD IMPROVE. WINDS WILL BE 9-14 KTS WITH GUSTS TO 22
KTS AND THEN DECREASE OVERNIGHT...EXCEPT AT KPDT WHERE SUSTAINED
WINDS WILL CONTINUE AROUND 14 KTS WITH GUSTS TO 25 KTS UNTIL AROUND
21/18Z TOMORROW. POLAN
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 36 51 36 50 / 20 10 70 60
ALW 39 52 36 49 / 20 10 70 60
PSC 31 47 36 51 / 10 10 70 40
YKM 28 44 30 50 / 10 20 70 40
HRI 32 50 34 50 / 10 10 70 50
ELN 27 41 27 42 / 10 30 70 40
RDM 22 42 30 45 / 10 30 70 40
LGD 32 41 33 44 / 60 20 80 70
GCD 29 42 29 42 / 40 10 70 60
DLS 36 45 36 52 / 10 30 80 40
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
SATURDAY : GREEN
SUNDAY : GREEN
MONDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
97/99/76
| 
