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000
FXUS66 KSEW 271809 RRA
AFDSEW

AREA FORECAST DISCUSSION...UPDATED TO ADD NEW AVIATION SECTION
NATIONAL WEATHER SERVICE SEATTLE WA
1008 AM PST THU NOV 27 2014

.SYNOPSIS...MOIST ONSHORE FLOW WILL GIVE PERIODS OF RAIN TO THE AREA
TODAY. A COLD FRONT WILL MOVE SOUTHEAST ACROSS THE AREA LATE TONIGHT
AND FRIDAY MORNING PRODUCING HEAVY RAIN OVER THE MOUNTAINS AND OVER
PARTS OF THE PUGET SOUND REGION. A CONVERGENCE ZONE WILL CONTINUE
OVER PUGET SOUND FRIDAY NIGHT...THEN ANOTHER COLD FRONT WILL MOVE
SOUTH THROUGH THE AREA LATE FRIDAY NIGHT INTO SATURDAY MORNING. SOME
SNOW OR RAIN AND SNOW MIXED IS LIKELY TO OCCUR WITH THE CONVERGENCE
ZONE AND ALONG THIS SECOND FRONT. COOL NORTHWEST FLOW ALOFT WILL
BRING MAINLY COOL AND DRY WEATHER SUNDAY THROUGH EARLY NEXT WEEK.

&&

.SHORT TERM...VERY ACTIVE AND CHANGEABLE WEATHER IS EXPECTED OVER
THE AREA THROUGH SATURDAY.

MOIST SW FLOW ALOFT AND ONSHORE FLOW WILL CONTINUE TODAY BRINGING
SOME LIGHT RAIN TO THE LOWLANDS AND HEAVY RAIN AT TIMES TO THE
MOUNTAINS. THE AIR MASS WILL REMAIN MOIST AND MILD WITH TEMPERATURES
IN THE 50S TODAY.

THE WARM FRONT FROM A COUPLE OF DAYS AGO IS STILL UP OVER B.C. AND
POISED TO MOVE BACK S OVER W WA AS A FAIRLY STRONG COLD FRONT
TONIGHT. RECENT MODELS ARE IN FAIRLY GOOD AGREEMENT WITH THE
TIMING...BRINGING THE FRONT TO A N COAST-BLI LINE AT 09Z/1 AM...TO A
HQM-SEA LINE 12Z-15Z/4AM-7AM...AND TO AN AST-CLS LINE AROUND 18Z/10
AM. HEAVY RAIN OVER THE MOUNTAINS WILL SHUT OFF BEHIND THE COLD
FRONT. SOME EARLIER MODELS SHOWED SOME RATHER HEAVY RAIN OVER OVER
THE GREATER PUGET SOUND REGION WITH THE FRONT...BUT THE NEWEST 12Z
RUNS HAVE TAKEN A STEP BACK. THE HIRES-ARW MODEL REMAINS THE
HEAVIEST PRECIP PRODUCER WITH AROUND AN INCH IN 3 HOURS WITH THE
FRONT. THE 12Z NAM12 AND HIRES-NMM MODELS ARE MUCH LIGHTER.
TEMPERATURES WILL REMAIN WARM ENOUGH TO KEEP THE PRECIP ALL RAIN.
TEMPERATURES WILL FALL INTO THE 30S TO LOWER 40S BY LATE FRIDAY
AFTERNOON.

BEHIND THE COLD FRONT A CONVERGENCE ZONE WILL FORM OVER CENTRAL
PUGET SOUND LATE FRIDAY AFTERNOON AND CONTINUE INTO FRIDAY NIGHT.
TEMPERATURES WILL FALL INTO THE LOWER TO MID 30S BY MID EVENING SO
THE CONVERGENCE ZONE MAY PRODUCE SOME SNOW FROM NORTH SEATTLE UP
THROUGH ARLINGTON. AT THE SAME TIME MODIFIED ARCTIC AIR WILL BEGIN
SPILLING OUT OF THE FRASER VALLEY. IT WILL BECOME VERY WINDY OVER
PARTS OF THE N INTERIOR FROM WHATCOM COUNTY ACROSS THE SAN JUAN
ISLANDS...BUT IT IS STILL UNCERTAIN WHETHER THE WINDS WILL END UP IN
THE WIND ADVISORY RANGE OR REACH HIGH WIND CRITERIA.

THE MOD-ARCTIC AIR WILL SPILL S ACROSS PUGET SOUND AS ANOTHER COLD
FRONT SATURDAY MORNING...AND SPILL WEST THROUGH THE STRAIT OF JUAN
DE FUCA. THERE IS POTENTIAL FOR A FEW INCHES OF SNOW OVER PUGET
SOUND SATURDAY MORNING AS THE FRONT MOVES S...AND OVER THE STRAIT AS
THE FLOW HITS THE NORTHERN OLYMPICS. THE SNOW WILL SHUT OFF IN THE
AFTERNOON AS THE AIR MASS DRIES OUT. KAM



.LONG TERM...PREVIOUS DISCUSSION FROM THE 330 AM AFD...AFTER A COLD
MORNING ON SUNDAY...EXPECT GRADUALLY MODERATING CONDITIONS LATER
SUNDAY THROUGH EARLY NEXT WEEK. MODELS VERY ON PRECIPITATION THREATS
STARTING MONDAY WITH THE GFS BRINGING SOUTHERN STREAM MOISTURE INTO
OREGON AND FAR SOUTHERN WASHINGTON AND THE ECMWF AND CANADIAN
SOLUTIONS BRINGING A NORTHERN STREAM TROUGH ACROSS THE AREA DURING
THE SAME PERIOD. AT THIS TIME THE DRY FORECAST WAS MAINTAINED BUT
CLOUDS WERE INCREASED. ALBRECHT

&&

.HYDROLOGY...THERE WAS A LULL IN HEAVY RAIN OVER THE CENTRAL
CASCADES LAST NIGHT WHICH ALLOWED THE SNOQUALMIE AND PUYALLUP RIVERS
TO FALL BELOW FLOOD STAGE. FLOOD WARNINGS ON THOSE RIVERS HAVE ENDED
FOR THE TIME BEING.

IN CONTRAST...HEAVY RAIN FELL LAST NIGHT OVER THE SOUTHWEST FACING
SLOPES OF THE OLYMPICS AND THE CASCADES FROM ABOUT THE STILLAGUAMISH
BASIN NORTHWARD. 12-HOUR AMOUNTS RANGE FROM ABOUT ONE INCH IN THE
SOUTH TO TWO INCHES IN THE NORTH. THE SKOKOMISH RIVER IS NOW ABOVE
FLOOD STAGE AND THE WARNING IS OUT. THE NORTH CASCADE RIVERS HAVE
STARTED RISING AGAIN WITH FLOODING ON AT LEAST SOME OF THEM LOOKING
LIKELY THIS EVENING OR TONIGHT.

SIGNIFICANT PRECIPITATION WILL CONTINUE THROUGH FRIDAY...WITH STRONG
OROGRAPHIC FORCING AS SOUTHWESTERLY LOW LEVEL WINDS OF 40 KT OR SO
CONTINUE. THE HEAVIEST PRECIPITATION WILL BE OVER THE OLYMPICS AND
NORTH CASCADES TODAY AND MOST OF TONIGHT...AND THEN THE FRONTAL BAND
AND HEAVIEST RAIN WILL GRADUALLY SHIFT SOUTHWARD ON FRIDAY. THE SNOW
LEVEL WILL BE 5500 TO 7000 FT THROUGH TONIGHT...AND IT SHOULD FALL
GRADUALLY ON FRIDAY AS THE COLD FRONT STARTS TO MOVE SOUTHEAST
THROUGH THE AREA.

IN THE NORTH CASCADES...THE NOOKSACK AND SKAGIT RIVERS CAME CLOSE TO
FLOODING ON WEDNESDAY...AND BOTH FACE A THREAT OF FLOODING IN THIS
EPISODE. IN ADDITION THE STILLAGUAMISH...SKYKOMISH...TOLT...
SNOQUALMIE...AND SNOHOMISH RIVERS -- ALL OF WHICH FLOODED OR NEARLY
FLOODED IN THE PAST COUPLE DAYS -- COULD FLOOD AS WELL. FLOODING ON
THESE CASCADE RIVERS WOULD PROBABLY BEGIN TONIGHT OR FRIDAY. A MAJOR
FLOODING EPISODE IS UNLIKELY...BUT IT WOULD BE NO SURPRISE IF MANY
OF THESE RIVERS HAVE MINOR TO MODERATE FLOODING.

THE CASCADES SOUTH OF THE SNOHOMISH BASIN WILL PROBABLY RECEIVE 2 TO
4 INCHES OF RAIN. MOST OF THAT COULD FALL ON FRIDAY AND SOME MODELS
-- ESPECIALLY THE UW WRF-GFS -- SHOW FAIRLY INTENSE RAINFALL IN THAT
AREA. SO THE RIVERS THERE FACE A THREAT OF FLOODING AS WELL. OF
COURSE SOME OF THEM RECENTLY FLOODED...AND THEY ARE ALL RUNNING
HIGH. A FLOOD WATCH REMAINS IN EFFECT.

THE COLD FRONT WILL MOVE SOUTHEAST OF WESTERN WASHINGTON FRIDAY
NIGHT...WITH COLD AND DRIER WEATHER LIKELY THIS WEEKEND. RIVERS WILL
RECEDE AND THE FLOOD THREAT WILL END FOR THE FORESEEABLE FUTURE.
MCDONNAL/BURKE

&&

.AVIATION...THE FLOW ALOFT IS W/SW. THE AIR MASS IS MOIST AND FAIRLY
UNSTABLE. RAIN SHOWERS WILL CONTINUE THROUGH THE DAY AND INTO
TONIGHT...WITH MVFR AND VFR CIGS AT MOST OF THE TERMINALS. A STRONG
COLD FRONT WILL MOVE SOUTH THROUGH THE AREA BETWEEN 10Z AND 17Z
EARLY FRIDAY MORNING...AND WINDS WILL SHARPLY SWITCH FROM S TO NW AT
THE TERMINALS. MODERATE RAIN AND DECREASED VISIBILITIES ARE POSSIBLE
WITH CONVERGENCE FROM THE FRONT.

KSEA...EXPECT RAIN SHOWERS THROUGH TODAY AND TONIGHT...WITH POSSIBLE
MODERATE RAIN EARLY FRIDAY JUST BEFORE THE FRONTAL PASSAGE. GUSTY
SOUTH WINDS WILL CHANGE TO N WITH THE PASSAGE OF THE COLD FRONT
AROUND 15Z. THERE MAY BE A BRIEF PERIOD FOR AN HOUR OR SO WHERE THE
WINDS AT BFI ARE FROM THE N AND WINDS AT SEATAC ARE FROM THE S JUST
BEFORE FRONTAL PASSAGE. JSMITH

&&

.MARINE...SMALL CRAFT ADVISORIES ARE IN EFFECT FOR ALL ZONES WITH
HIGHER PRESSURE IN THE SOUTH AND LOWER PRESSURE IN THE NORTH
PRODUCING HIGH END SMALL CRAFT ADVISORY LEVEL WINDS. PRESSURE
GRADIENTS WILL REMAIN TIGHT TONIGHT THROUGH FRI MORNING AS A WELL
DEVELOPED COLD FRONT SHIFTS SOUTH INTO WESTERN WA. WINDS WILL SWITCH
FROM THE SW TO THE N OR NW AS THE FRONT MOVES THROUGH.

STRONG HIGH PRES OVER INTERIOR B.C. WILL BRING N/NE FRASER RIVER
OUTFLOW WINDS LATE FRI NIGHT INTO SAT WITH GALES LIKELY OVER THE
NORTHERN INLAND WATERS. OFFSHORE FLOW WILL PREVAIL SUN AND MON WITH
HIGH PRES EAST OF THE CASCADES. JSMITH

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES AND WARNINGS IN EFFECT FOR PORTIONS OF
      WESTERN WASHINGTON.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
     SMALL CRAFT ADVISORY GRAYS HARBOR BAR FOR ROUGH BAR.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
















000
FXUS66 KSEW 271744
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
944 AM PST THU NOV 27 2014

.SYNOPSIS...MOIST ONSHORE FLOW WILL GIVE PERIODS OF RAIN TO THE AREA
TODAY. A COLD FRONT WILL MOVE SOUTHEAST ACROSS THE AREA LATE TONIGHT
AND FRIDAY MORNING PRODUCING HEAVY RAIN OVER THE MOUNTAINS AND OVER
PARTS OF THE PUGET SOUND REGION. A CONVERGENCE ZONE WILL CONTINUE
OVER PUGET SOUND FRIDAY NIGHT...THEN ANOTHER COLD FRONT WILL MOVE
SOUTH THROUGH THE AREA LATE FRIDAY NIGHT INTO SATURDAY MORNING. SOME
SNOW OR RAIN AND SNOW MIXED IS LIKELY TO OCCUR WITH THE CONVERGENCE
ZONE AND ALONG THIS SECOND FRONT. COOL NORTHWEST FLOW ALOFT WILL
BRING MAINLY COOL AND DRY WEATHER SUNDAY THROUGH EARLY NEXT WEEK.

&&

.SHORT TERM...VERY ACTIVE AND CHANGEABLE WEATHER IS EXPECTED OVER
THE AREA THROUGH SATURDAY.

MOIST SW FLOW ALOFT AND ONSHORE FLOW WILL CONTINUE TODAY BRINGING
SOME LIGHT RAIN TO THE LOWLANDS AND HEAVY RAIN AT TIMES TO THE
MOUNTAINS. THE AIR MASS WILL REMAIN MOIST AND MILD WITH TEMPERATURES
IN THE 50S TODAY.

THE WARM FRONT FROM A COUPLE OF DAYS AGO IS STILL UP OVER B.C. AND
POISED TO MOVE BACK S OVER W WA AS A FAIRLY STRONG COLD FRONT
TONIGHT. RECENT MODELS ARE IN FAIRLY GOOD AGREEMENT WITH THE
TIMING...BRINGING THE FRONT TO A N COAST-BLI LINE AT 09Z/1 AM...TO A
HQM-SEA LINE 12Z-15Z/4AM-7AM...AND TO AN AST-CLS LINE AROUND 18Z/10
AM. HEAVY RAIN OVER THE MOUNTAINS WILL SHUT OFF BEHIND THE COLD
FRONT. SOME EARLIER MODELS SHOWED SOME RATHER HEAVY RAIN OVER OVER
THE GREATER PUGET SOUND REGION WITH THE FRONT...BUT THE NEWEST 12Z
RUNS HAVE TAKEN A STEP BACK. THE HIRES-ARW MODEL REMAINS THE
HEAVIEST PRECIP PRODUCER WITH AROUND AN INCH IN 3 HOURS WITH THE
FRONT. THE 12Z NAM12 AND HIRES-NMM MODELS ARE MUCH LIGHTER.
TEMPERATURES WILL REMAIN WARM ENOUGH TO KEEP THE PRECIP ALL RAIN.
TEMPERATURES WILL FALL INTO THE 30S TO LOWER 40S BY LATE FRIDAY
AFTERNOON.

BEHIND THE COLD FRONT A CONVERGENCE ZONE WILL FORM OVER CENTRAL
PUGET SOUND LATE FRIDAY AFTERNOON AND CONTINUE INTO FRIDAY NIGHT.
TEMPERATURES WILL FALL INTO THE LOWER TO MID 30S BY MID EVENING SO
THE CONVERGENCE ZONE MAY PRODUCE SOME SNOW FROM NORTH SEATTLE UP
THROUGH ARLINGTON. AT THE SAME TIME MODIFIED ARCTIC AIR WILL BEGIN
SPILLING OUT OF THE FRASER VALLEY. IT WILL BECOME VERY WINDY OVER
PARTS OF THE N INTERIOR FROM WHATCOM COUNTY ACROSS THE SAN JUAN
ISLANDS...BUT IT IS STILL UNCERTAIN WHETHER THE WINDS WILL END UP IN
THE WIND ADVISORY RANGE OR REACH HIGH WIND CRITERIA.

THE MOD-ARCTIC AIR WILL SPILL S ACROSS PUGET SOUND AS ANOTHER COLD
FRONT SATURDAY MORNING...AND SPILL WEST THROUGH THE STRAIT OF JUAN
DE FUCA. THERE IS POTENTIAL FOR A FEW INCHES OF SNOW OVER PUGET
SOUND SATURDAY MORNING AS THE FRONT MOVES S...AND OVER THE STRAIT AS
THE FLOW HITS THE NORTHERN OLYMPICS. THE SNOW WILL SHUT OFF IN THE
AFTERNOON AS THE AIR MASS DRIES OUT. KAM



.LONG TERM...PREVIOUS DISCUSSION FROM THE 330 AM AFD...AFTER A COLD
MORNING ON SUNDAY...EXPECT GRADUALLY MODERATING CONDITIONS LATER
SUNDAY THROUGH EARLY NEXT WEEK. MODELS VERY ON PRECIPITATION THREATS
STARTING MONDAY WITH THE GFS BRINGING SOUTHERN STREAM MOISTURE INTO
OREGON AND FAR SOUTHERN WASHINGTON AND THE ECMWF AND CANADIAN
SOLUTIONS BRINGING A NORTHERN STREAM TROUGH ACROSS THE AREA DURING
THE SAME PERIOD. AT THIS TIME THE DRY FORECAST WAS MAINTAINED BUT
CLOUDS WERE INCREASED. ALBRECHT

&&

.HYDROLOGY...THERE WAS A LULL IN HEAVY RAIN OVER THE CENTRAL
CASCADES LAST NIGHT WHICH ALLOWED THE SNOQUALMIE AND PUYALLUP RIVERS
TO FALL BELOW FLOOD STAGE. FLOOD WARNINGS ON THOSE RIVERS HAVE ENDED
FOR THE TIME BEING.

IN CONTRAST...HEAVY RAIN FELL LAST NIGHT OVER THE SOUTHWEST FACING
SLOPES OF THE OLYMPICS AND THE CASCADES FROM ABOUT THE STILLAGUAMISH
BASIN NORTHWARD. 12-HOUR AMOUNTS RANGE FROM ABOUT ONE INCH IN THE
SOUTH TO TWO INCHES IN THE NORTH. THE SKOKOMISH RIVER IS NOW ABOVE
FLOOD STAGE AND THE WARNING IS OUT. THE NORTH CASCADE RIVERS HAVE
STARTED RISING AGAIN WITH FLOODING ON AT LEAST SOME OF THEM LOOKING
LIKELY THIS EVENING OR TONIGHT.

SIGNIFICANT PRECIPITATION WILL CONTINUE THROUGH FRIDAY...WITH STRONG
OROGRAPHIC FORCING AS SOUTHWESTERLY LOW LEVEL WINDS OF 40 KT OR SO
CONTINUE. THE HEAVIEST PRECIPITATION WILL BE OVER THE OLYMPICS AND
NORTH CASCADES TODAY AND MOST OF TONIGHT...AND THEN THE FRONTAL BAND
AND HEAVIEST RAIN WILL GRADUALLY SHIFT SOUTHWARD ON FRIDAY. THE SNOW
LEVEL WILL BE 5500 TO 7000 FT THROUGH TONIGHT...AND IT SHOULD FALL
GRADUALLY ON FRIDAY AS THE COLD FRONT STARTS TO MOVE SOUTHEAST
THROUGH THE AREA.

IN THE NORTH CASCADES...THE NOOKSACK AND SKAGIT RIVERS CAME CLOSE TO
FLOODING ON WEDNESDAY...AND BOTH FACE A THREAT OF FLOODING IN THIS
EPISODE. IN ADDITION THE STILLAGUAMISH...SKYKOMISH...TOLT...
SNOQUALMIE...AND SNOHOMISH RIVERS -- ALL OF WHICH FLOODED OR NEARLY
FLOODED IN THE PAST COUPLE DAYS -- COULD FLOOD AS WELL. FLOODING ON
THESE CASCADE RIVERS WOULD PROBABLY BEGIN TONIGHT OR FRIDAY. A MAJOR
FLOODING EPISODE IS UNLIKELY...BUT IT WOULD BE NO SURPRISE IF MANY
OF THESE RIVERS HAVE MINOR TO MODERATE FLOODING.

THE CASCADES SOUTH OF THE SNOHOMISH BASIN WILL PROBABLY RECEIVE 2 TO
4 INCHES OF RAIN. MOST OF THAT COULD FALL ON FRIDAY AND SOME MODELS
-- ESPECIALLY THE UW WRF-GFS -- SHOW FAIRLY INTENSE RAINFALL IN THAT
AREA. SO THE RIVERS THERE FACE A THREAT OF FLOODING AS WELL. OF
COURSE SOME OF THEM RECENTLY FLOODED...AND THEY ARE ALL RUNNING
HIGH. A FLOOD WATCH REMAINS IN EFFECT.

THE COLD FRONT WILL MOVE SOUTHEAST OF WESTERN WASHINGTON FRIDAY
NIGHT...WITH COLD AND DRIER WEATHER LIKELY THIS WEEKEND. RIVERS WILL
RECEDE AND THE FLOOD THREAT WILL END FOR THE FORESEEABLE FUTURE.
MCDONNAL/BURKE

&&

.AVIATION...DELAYED....EXPECT RAIN AT TIMES THIS MORNING AS A COLD
FRONT PUSHES THROUGH WESTERN WA. THE FLOW ALOFT IS WESTERLY. MVFR
CIGS ARE POSSIBLE THIS MORNING IN -RA. GUSTY SOUTH WINDS ARE ALSO
EXPECTED WITH THIS FRONT. MOIST WESTERLY FLOW WILL CONTINUE THIS
AFTERNOON WITH SHOWERS MAINLY AFFECTING THE COAST AND MOUNTAINS.
RAIN WILL CONTINUE TONIGHT AS ANOTHER COLD FRONT SHIFTS S/SE INTO
WESTERN WA. 33

KSEA...EXPECT LIGHT RAIN AT TIMES TODAY WITH CIGS NEAR 3000 FT.
GUSTY SOUTH WINDS 20015G25KT EXPECTED AT THE TERMINAL THROUGHOUT THE
DAY. 33

&&

.MARINE...SMALL CRAFT ADVISORIES ARE IN EFFECT FOR ALL ZONES WITH
HIGHER PRESSURE IN THE SOUTH AND LOWER PRESSURE IN THE NORTH
PRODUCING HIGH END SMALL CRAFT ADVISORY LEVEL WINDS. PRESSURE
GRADIENTS WILL REMAIN TIGHT TONIGHT THROUGH FRI MORNING AS A WELL
DEVELOPED COLD FRONT SHIFTS SOUTH INTO WESTERN WA. WINDS WILL SWITCH
FROM THE SW TO THE N OR NW AS THE FRONT MOVES THROUGH.

STRONG HIGH PRES OVER INTERIOR B.C. WILL BRING N/NE FRASER RIVER
OUTFLOW WINDS LATE FRI NIGHT INTO SAT WITH GALES LIKELY OVER THE
NORTHERN INLAND WATERS. OFFSHORE FLOW WILL PREVAIL SUN AND MON WITH
HIGH PRES EAST OF THE CASCADES. JSMITH

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES AND WARNINGS IN EFFECT FOR PORTIONS OF
      WESTERN WASHINGTON.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
     SMALL CRAFT ADVISORY GRAYS HARBOR BAR FOR ROUGH BAR.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML













000
FXUS66 KSEW 271122
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
330 AM PST THU NOV 27 2014

.SYNOPSIS...MOIST ONSHORE FLOW WILL GIVE PERIODS OF RAIN TO THE AREA
TODAY. A COLD FRONT WILL MOVE SOUTHEAST ACROSS THE AREA FRIDAY
MORNING GIVING FALLING TEMPERATURES DURING THE AFTERNOON. A STRONG
COLD FRONT WILL MOVE SOUTH THROUGH THE AREA FRIDAY NIGHT INTO
SATURDAY. SOME SNOW OR RAIN AND SNOW MIXED IS LIKELY TO OCCUR ALONG
THIS SECOND FRONT LATE FRIDAY NIGHT INTO SATURDAY. STRONG FRASER
OUTFLOW WILL GIVE WINDY CONDITIONS TO THE NORTH INTERIOR LATE FRIDAY
NIGHT INTO SATURDAY. COOL AND MAINLY DRY WEATHER IS EXPECTED SUNDAY
THROUGH EARLY NEXT WEEK.

&&

.SHORT TERM...VERY ACTIVE AND CHANGEABLE WEATHER IS EXPECTED OVER
THE AREA DURING THE SHORT TERM PERIOD.

A FRONTAL FEATURE MOVED INLAND THROUGH THE AREA EARLY THIS MORNING.
WHILE IT HAS BEEN WINDY ACROSS THE NORTH INTERIOR AND ALONG THE
NORTH COAST...WINDS HAVE BEEN BELOW WIND ADVISORY CRITERIA. WILL
ALLOW THE WIND ADVISORY TO EXPIRE AT 4 AM PST.

WHILE A WEAK FRONTAL SYSTEM IS MOVING ACROSS THE AREA EARLY THIS
MORNING...THE AIR MASS BEHIND THE FRONT IS ORIGINATING FROM THE
SUBTROPICAL CENTRAL PACIFIC. SO...WE CAN EXPECT A CONTINUATION OF
THE RATHER WARM AND MUGGY AIR MASS THAT WE HAVE SEEN OVER THE PAST
24 HOURS WITH TEMPERATURES REMAINING NEAR STEADY IN THE 50S THROUGH
TONIGHT. STRONG ONSHORE PRESSURE GRADIENTS AND THE HIGH MOISTURE
CONTENT OF THE LOW LEVEL AIR MASS - WITH DEWPOINTS AROUND 50 - IS
RESULTING IN GOOD OROGRAPHIC PRECIPITATION AMOUNTS ON THE WEST
SLOPES OF THE MOUNTAINS. LITTLE CHANGE IN THE OVERALL PATTERN IS
EXPECTED THROUGH TONIGHT...WITH POSSIBLY SOME INCREASE IN ONSHORE
FLOW TONIGHT AS A WAVE OF LOW PRESSURE MOVES BY TO THE NORTH OF THE
AREA. SEE THE HYDROLOGY SECTION BELOW FOR DETAILS ON FORECAST
PRECIPITATION IN THE AREA AND ITS IMPACT ON LOCAL RIVER.

BIG CHANGES BEGIN TO OCCUR FRIDAY MORNING. A WEAK UPPER LEVEL
TROUGH THAT IS PASSING SOUTHWARD THROUGH THE ALASKAN PANHANDLE THIS
MORNING IS FORECAST BY ALL MODELS TO SHARPEN AND DIG INTO WESTERN
WASHINGTON FRIDAY AFTERNOON. THIS WILL INTENSIFY THE FRONTAL SYSTEM
THAT NOW SITS OVER THE QUEEN CHARLOTTE SOUND AND SWEEP IT SOUTHEAST
ACROSS THE AREA FRIDAY MORNING. STRONG HEIGHT FALLS AT 500 MB BEGIN
FRIDAY MORNING AND CONTINUE THROUGH FRIDAY NIGHT...FALLING FROM NEAR
550 DAM TO AROUND 520 DAM PER THE 00Z ECMWF SOLUTION. THE GFS SHOWS
HEIGHT FALLS A BIT WEAKER THAN THE ECMWF...BUT IS STILL VERY
IMPRESSIVE AND IS RATHER CONSISTENT. SO A SHARP FRONT MOVES SE
ACROSS THE AREA DURING THE DAY WITH EARLY MORNING HIGH TEMPERATURES
IN MOST AREAS. PRECIPITATION AMOUNTS WITH THE FRONT PER MESOSCALE
MODELS LIKE THE UW WRFGFS ARE IMPRESSIVE FRIDAY MORNING. MOST AREAS
WILL BE BREEZY TO WINDY THROUGH FRIDAY.

A MODIFIED ARCTIC COLD FRONT WILL LIKELY REACH THE FAR NORTH
INTERIOR EARLY FRIDAY EVENING THEN TAKE ITS TIME MOVING SOUTH TO
AROUND EVERETT ABOUT MIDNIGHT FRIDAY NIGHT AND THROUGH THE SEATTLE
AREA SATURDAY MORNING. THIS FRONT WILL BE ACCOMPANIED BY A SHARP
UPPER LEVEL TROUGH AND POSSIBLY A LEE SIDE LOW THAT FORMS OFF
VANCOUVER ISLAND AND MOVES INLAND SOMEWHERE AROUND THE SOUTH
INTERIOR SATURDAY MORNING. A CONVERGENCE ZONE-LIKE FEATURE CAN BE
EXPECTED AHEAD OF THE MODIFIED ARCTIC FRONT. SNOW LEVELS WILL FALL
FRIDAY NIGHT...MOSTLY DUE TO THE COOLING ALOFT...THEN SHOULD BE NEAR
SEA LEVEL SATURDAY MORNING ALL AREAS. SNOWFALL AMOUNTS IN THE
LOWLANDS ARE HIGHLY UNCERTAIN AT THIS TIME. FORECAST MODELS RANGE
FROM ABOUT AN INCH IN THE GFS SOLUTION TO POSSIBLY 3 TO 5 INCHES
OVER PORTIONS OF THE NORTH INTERIOR DOWN TO THE NORTHERN PORTIONS OF
SEATTLE PER THE ECMWF...NAM12 AND CANADIAN SOLUTIONS. CURRENT
FORECASTS WILL BE A MODEL BLEND BETWEEN THESE AMOUNTS AND WILL
LIKELY NEED TO BE ADJUSTED AS WE GET CLOSER TO THE EVENT.

BEHIND THE MODIFIED ARCTIC FRONT...STRONG FRASER OUTFLOW WILL AFFECT
THE NORTH INTERIOR. MODELS GENERALLY AGREE THAT BELLINGHAM TO
WILLIAMS LAKE PRESSURE GRADIENTS WILL FALL TO -18 TO -23 MB. THIS
WOULD RESULT IN N TO NE WINDS 25 TO 40 MPH WITH GUSTS TO 55 MPH SAT
MORNING BELLINGHAM NORTHWARD AND IN THE SAN JUANS.

WILL ISSUE A SPECIAL WEATHER STATEMENT FOR THE RAPIDLY CHANGING
CONDITIONS...POSSIBLE LOWLAND SNOW...AND LOCALLY VERY WINDY
CONDITIONS FRIDAY THROUGH SATURDAY. ALBRECHT

.LONG TERM...AFTER A COLD MORNING ON SUNDAY...EXPECT GRADUALLY
MODERATING CONDITIONS LATER SUNDAY THROUGH EARLY NEXT WEEK. MODELS
VERY ON PRECIPITATION THREATS STARTING MONDAY WITH THE GFS BRINGING
SOUTHERN STREAM MOISTURE INTO OREGON AND FAR SOUTHERN WASHINGTON AND
THE ECMWF AND CANADIAN SOLUTIONS BRINGING A NORTHERN STREAM TROUGH
ACROSS THE AREA DURING THE SAME PERIOD. AT THIS TIME THE DRY
FORECAST WAS MAINTAINED BUT CLOUDS WERE INCREASED. ALBRECHT

&&

.HYDROLOGY...THE SNOQUALMIE RIVER NEAR CARNATION REMAINS ABOVE FLOOD
STAGE AS A RESULT OF THE HEAVY RAIN THAT FELL MONDAY AFTERNOON
THROUGH TUESDAY NIGHT...BUT IT IS FALLING AND WILL DROP BELOW FLOOD
STAGE IN A FEW HOURS.

RAIN BEGAN SPREADING INTO WESTERN WASHINGTON AHEAD OF THE NEXT
FRONTAL SYSTEM LATE WEDNESDAY. AS EXPECTED THE HEAVIEST RAIN HAS
BEEN OVER THE SOUTHWEST FACING SLOPES OF THE OLYMPICS...AND IN THE
CASCADES FROM ROUGHLY THE SNOHOMISH BASIN NORTHWARD. MANY STATIONS
THERE ARE REPORTING 0.6 TO 1.3 INCHES IN THE LAST 12 HOURS...AND
MOST OF THE RIVERS IN THE REGION HAVE STARTED RISING AGAIN.

SIGNIFICANT PRECIPITATION WILL CONTINUE THROUGH FRIDAY...WITH STRONG
OROGRAPHIC FORCING AS SOUTHWESTERLY LOW LEVEL WINDS OF 40 KT OR SO
CONTINUE. THE HEAVIEST PRECIPITATION WILL BE OVER THE OLYMPICS AND
NORTH CASCADES TODAY AND MOST OF TONIGHT...AND THEN THE FRONTAL BAND
AND HEAVIEST RAIN WILL GRADUALLY SHIFT SOUTHWARD ON FRIDAY. THE SNOW
LEVEL WILL BE 5500 TO 7000 FT THROUGH TONIGHT...AND IT SHOULD FALL
GRADUALLY ON FRIDAY AS THE COLD FRONT STARTS TO MOVE SOUTHEAST
THROUGH THE AREA.

ANOTHER 3.0 TO 5.5 INCHES OF PRECIPITATION IS LIKELY IN THE OLYMPICS
AND CASCADES FROM THE SNOHOMISH BASIN NORTHWARD THROUGH FRIDAY. THIS
COULD CAUSE THE SKOKOMISH RIVER TO FLOOD...AND IT COULD REACH FLOOD
STAGE THIS EVENING. IN THE NORTH CASCADES...THE NOOKSACK AND SKAGIT
RIVERS CAME CLOSE TO FLOODING ON WEDNESDAY...AND BOTH FACE A THREAT
OF FLOODING IN THIS EPISODE. IN ADDITION THE STILLAGUAMISH...
SKYKOMISH...TOLT...SNOQUALMIE...AND SNOHOMISH RIVERS -- ALL OF WHICH
FLOODED OR NEARLY FLOODED IN THE PAST COUPLE DAYS -- COULD FLOOD AS
WELL. FLOODING ON THESE CASCADE RIVERS WOULD PROBABLY BEGIN TONIGHT
OR FRIDAY. A MAJOR FLOODING EPISODE IS UNLIKELY...BUT IT WOULD BE NO
SURPRISE IF MANY OF THESE RIVERS HAVE MINOR TO MODERATE FLOODING.

THE CASCADES SOUTH OF THE SNOHOMISH BASIN WILL PROBABLY RECEIVE 2 TO
4 INCHES OF RAIN. MOST OF THAT COULD FALL ON FRIDAY AND SOME MODELS
-- ESPECIALLY THE UW WRF-GFS -- SHOW FAIRLY INTENSE RAINFALL IN THAT
AREA. SO THE RIVERS THERE FACE A THREAT OF FLOODING AS WELL. OF
COURSE SOME OF THEM RECENTLY FLOODED...AND THEY ARE ALL RUNNING
HIGH.

THE COLD FRONT SHOULD MOVE SOUTHEAST OF WESTERN WASHINGTON FRIDAY
NIGHT...WITH COLD AND DRIER WEATHER LIKELY THIS WEEKEND. RIVERS
SHOULD THEN RECEDE AND THE FLOOD THREAT WILL END FOR THE FORESEEABLE
FUTURE.   MCDONNAL

&&

.AVIATION...EXPECT RAIN AT TIMES THIS MORNING AS A COLD FRONT PUSHES
THROUGH WESTERN WA. THE FLOW ALOFT IS WESTERLY. MVFR CIGS ARE
POSSIBLE THIS MORNING IN -RA. GUSTY SOUTH WINDS ARE ALSO EXPECTED
WITH THIS FRONT. MOIST WESTERLY FLOW WILL CONTINUE THIS AFTERNOON
WITH SHOWERS MAINLY AFFECTING THE COAST AND MOUNTAINS. RAIN WILL
CONTINUE TONIGHT AS ANOTHER COLD FRONT SHIFTS S/SE INTO WESTERN WA.
33

KSEA...EXPECT LIGHT RAIN AT TIMES TODAY WITH CIGS NEAR 3000 FT.
GUSTY SOUTH WINDS 20015G25KT EXPECTED AT THE TERMINAL THROUGHOUT THE
DAY. 33

&&

.MARINE...A COLD FRONT IS PUSHING THROUGH WESTERN WA EARLY THIS
MORNING WITH MODERATE SOUTH/SOUTHWEST WINDS ACROSS THE WATERS -
SMALL CRAFT ADVISORIES ARE IN EFFECT FOR ALL ZONES. PRESSURE
GRADIENTS WILL REMAIN TIGHT TONIGHT THROUGH FRI MORNING AS ANOTHER
COLD FRONT SHIFTS SOUTH INTO WESTERN WA. STRONG HIGH PRES OVER
INTERIOR B.C. WILL BRING N/NE FRASER RIVER OUTFLOW WINDS LATE FRI
NIGHT INTO SAT WITH GALES POSSIBLE OVER THE NORTHERN INLAND WATERS.
OFFSHORE FLOW WILL PREVAIL SUN AND MON WITH HIGH PRES EAST OF THE
CASCADES. 33

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES AND WARNINGS IN EFFECT FOR PORTIONS OF
      WESTERN WASHINGTON.

PZ...SMALL CRAFT ADVISORY ALL WATERS.
     SMALL CRAFT ADVISORY GRAYS HARBOR BAR FOR ROUGH BAR.

&&

$$

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000
FXUS66 KSEW 271122
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
330 AM PST THU NOV 27 2014

.SYNOPSIS...MOIST ONSHORE FLOW WILL GIVE PERIODS OF RAIN TO THE AREA
TODAY. A COLD FRONT WILL MOVE SOUTHEAST ACROSS THE AREA FRIDAY
MORNING GIVING FALLING TEMPERATURES DURING THE AFTERNOON. A STRONG
COLD FRONT WILL MOVE SOUTH THROUGH THE AREA FRIDAY NIGHT INTO
SATURDAY. SOME SNOW OR RAIN AND SNOW MIXED IS LIKELY TO OCCUR ALONG
THIS SECOND FRONT LATE FRIDAY NIGHT INTO SATURDAY. STRONG FRASER
OUTFLOW WILL GIVE WINDY CONDITIONS TO THE NORTH INTERIOR LATE FRIDAY
NIGHT INTO SATURDAY. COOL AND MAINLY DRY WEATHER IS EXPECTED SUNDAY
THROUGH EARLY NEXT WEEK.

&&

.SHORT TERM...VERY ACTIVE AND CHANGEABLE WEATHER IS EXPECTED OVER
THE AREA DURING THE SHORT TERM PERIOD.

A FRONTAL FEATURE MOVED INLAND THROUGH THE AREA EARLY THIS MORNING.
WHILE IT HAS BEEN WINDY ACROSS THE NORTH INTERIOR AND ALONG THE
NORTH COAST...WINDS HAVE BEEN BELOW WIND ADVISORY CRITERIA. WILL
ALLOW THE WIND ADVISORY TO EXPIRE AT 4 AM PST.

WHILE A WEAK FRONTAL SYSTEM IS MOVING ACROSS THE AREA EARLY THIS
MORNING...THE AIR MASS BEHIND THE FRONT IS ORIGINATING FROM THE
SUBTROPICAL CENTRAL PACIFIC. SO...WE CAN EXPECT A CONTINUATION OF
THE RATHER WARM AND MUGGY AIR MASS THAT WE HAVE SEEN OVER THE PAST
24 HOURS WITH TEMPERATURES REMAINING NEAR STEADY IN THE 50S THROUGH
TONIGHT. STRONG ONSHORE PRESSURE GRADIENTS AND THE HIGH MOISTURE
CONTENT OF THE LOW LEVEL AIR MASS - WITH DEWPOINTS AROUND 50 - IS
RESULTING IN GOOD OROGRAPHIC PRECIPITATION AMOUNTS ON THE WEST
SLOPES OF THE MOUNTAINS. LITTLE CHANGE IN THE OVERALL PATTERN IS
EXPECTED THROUGH TONIGHT...WITH POSSIBLY SOME INCREASE IN ONSHORE
FLOW TONIGHT AS A WAVE OF LOW PRESSURE MOVES BY TO THE NORTH OF THE
AREA. SEE THE HYDROLOGY SECTION BELOW FOR DETAILS ON FORECAST
PRECIPITATION IN THE AREA AND ITS IMPACT ON LOCAL RIVER.

BIG CHANGES BEGIN TO OCCUR FRIDAY MORNING. A WEAK UPPER LEVEL
TROUGH THAT IS PASSING SOUTHWARD THROUGH THE ALASKAN PANHANDLE THIS
MORNING IS FORECAST BY ALL MODELS TO SHARPEN AND DIG INTO WESTERN
WASHINGTON FRIDAY AFTERNOON. THIS WILL INTENSIFY THE FRONTAL SYSTEM
THAT NOW SITS OVER THE QUEEN CHARLOTTE SOUND AND SWEEP IT SOUTHEAST
ACROSS THE AREA FRIDAY MORNING. STRONG HEIGHT FALLS AT 500 MB BEGIN
FRIDAY MORNING AND CONTINUE THROUGH FRIDAY NIGHT...FALLING FROM NEAR
550 DAM TO AROUND 520 DAM PER THE 00Z ECMWF SOLUTION. THE GFS SHOWS
HEIGHT FALLS A BIT WEAKER THAN THE ECMWF...BUT IS STILL VERY
IMPRESSIVE AND IS RATHER CONSISTENT. SO A SHARP FRONT MOVES SE
ACROSS THE AREA DURING THE DAY WITH EARLY MORNING HIGH TEMPERATURES
IN MOST AREAS. PRECIPITATION AMOUNTS WITH THE FRONT PER MESOSCALE
MODELS LIKE THE UW WRFGFS ARE IMPRESSIVE FRIDAY MORNING. MOST AREAS
WILL BE BREEZY TO WINDY THROUGH FRIDAY.

A MODIFIED ARCTIC COLD FRONT WILL LIKELY REACH THE FAR NORTH
INTERIOR EARLY FRIDAY EVENING THEN TAKE ITS TIME MOVING SOUTH TO
AROUND EVERETT ABOUT MIDNIGHT FRIDAY NIGHT AND THROUGH THE SEATTLE
AREA SATURDAY MORNING. THIS FRONT WILL BE ACCOMPANIED BY A SHARP
UPPER LEVEL TROUGH AND POSSIBLY A LEE SIDE LOW THAT FORMS OFF
VANCOUVER ISLAND AND MOVES INLAND SOMEWHERE AROUND THE SOUTH
INTERIOR SATURDAY MORNING. A CONVERGENCE ZONE-LIKE FEATURE CAN BE
EXPECTED AHEAD OF THE MODIFIED ARCTIC FRONT. SNOW LEVELS WILL FALL
FRIDAY NIGHT...MOSTLY DUE TO THE COOLING ALOFT...THEN SHOULD BE NEAR
SEA LEVEL SATURDAY MORNING ALL AREAS. SNOWFALL AMOUNTS IN THE
LOWLANDS ARE HIGHLY UNCERTAIN AT THIS TIME. FORECAST MODELS RANGE
FROM ABOUT AN INCH IN THE GFS SOLUTION TO POSSIBLY 3 TO 5 INCHES
OVER PORTIONS OF THE NORTH INTERIOR DOWN TO THE NORTHERN PORTIONS OF
SEATTLE PER THE ECMWF...NAM12 AND CANADIAN SOLUTIONS. CURRENT
FORECASTS WILL BE A MODEL BLEND BETWEEN THESE AMOUNTS AND WILL
LIKELY NEED TO BE ADJUSTED AS WE GET CLOSER TO THE EVENT.

BEHIND THE MODIFIED ARCTIC FRONT...STRONG FRASER OUTFLOW WILL AFFECT
THE NORTH INTERIOR. MODELS GENERALLY AGREE THAT BELLINGHAM TO
WILLIAMS LAKE PRESSURE GRADIENTS WILL FALL TO -18 TO -23 MB. THIS
WOULD RESULT IN N TO NE WINDS 25 TO 40 MPH WITH GUSTS TO 55 MPH SAT
MORNING BELLINGHAM NORTHWARD AND IN THE SAN JUANS.

WILL ISSUE A SPECIAL WEATHER STATEMENT FOR THE RAPIDLY CHANGING
CONDITIONS...POSSIBLE LOWLAND SNOW...AND LOCALLY VERY WINDY
CONDITIONS FRIDAY THROUGH SATURDAY. ALBRECHT

.LONG TERM...AFTER A COLD MORNING ON SUNDAY...EXPECT GRADUALLY
MODERATING CONDITIONS LATER SUNDAY THROUGH EARLY NEXT WEEK. MODELS
VERY ON PRECIPITATION THREATS STARTING MONDAY WITH THE GFS BRINGING
SOUTHERN STREAM MOISTURE INTO OREGON AND FAR SOUTHERN WASHINGTON AND
THE ECMWF AND CANADIAN SOLUTIONS BRINGING A NORTHERN STREAM TROUGH
ACROSS THE AREA DURING THE SAME PERIOD. AT THIS TIME THE DRY
FORECAST WAS MAINTAINED BUT CLOUDS WERE INCREASED. ALBRECHT

&&

.HYDROLOGY...THE SNOQUALMIE RIVER NEAR CARNATION REMAINS ABOVE FLOOD
STAGE AS A RESULT OF THE HEAVY RAIN THAT FELL MONDAY AFTERNOON
THROUGH TUESDAY NIGHT...BUT IT IS FALLING AND WILL DROP BELOW FLOOD
STAGE IN A FEW HOURS.

RAIN BEGAN SPREADING INTO WESTERN WASHINGTON AHEAD OF THE NEXT
FRONTAL SYSTEM LATE WEDNESDAY. AS EXPECTED THE HEAVIEST RAIN HAS
BEEN OVER THE SOUTHWEST FACING SLOPES OF THE OLYMPICS...AND IN THE
CASCADES FROM ROUGHLY THE SNOHOMISH BASIN NORTHWARD. MANY STATIONS
THERE ARE REPORTING 0.6 TO 1.3 INCHES IN THE LAST 12 HOURS...AND
MOST OF THE RIVERS IN THE REGION HAVE STARTED RISING AGAIN.

SIGNIFICANT PRECIPITATION WILL CONTINUE THROUGH FRIDAY...WITH STRONG
OROGRAPHIC FORCING AS SOUTHWESTERLY LOW LEVEL WINDS OF 40 KT OR SO
CONTINUE. THE HEAVIEST PRECIPITATION WILL BE OVER THE OLYMPICS AND
NORTH CASCADES TODAY AND MOST OF TONIGHT...AND THEN THE FRONTAL BAND
AND HEAVIEST RAIN WILL GRADUALLY SHIFT SOUTHWARD ON FRIDAY. THE SNOW
LEVEL WILL BE 5500 TO 7000 FT THROUGH TONIGHT...AND IT SHOULD FALL
GRADUALLY ON FRIDAY AS THE COLD FRONT STARTS TO MOVE SOUTHEAST
THROUGH THE AREA.

ANOTHER 3.0 TO 5.5 INCHES OF PRECIPITATION IS LIKELY IN THE OLYMPICS
AND CASCADES FROM THE SNOHOMISH BASIN NORTHWARD THROUGH FRIDAY. THIS
COULD CAUSE THE SKOKOMISH RIVER TO FLOOD...AND IT COULD REACH FLOOD
STAGE THIS EVENING. IN THE NORTH CASCADES...THE NOOKSACK AND SKAGIT
RIVERS CAME CLOSE TO FLOODING ON WEDNESDAY...AND BOTH FACE A THREAT
OF FLOODING IN THIS EPISODE. IN ADDITION THE STILLAGUAMISH...
SKYKOMISH...TOLT...SNOQUALMIE...AND SNOHOMISH RIVERS -- ALL OF WHICH
FLOODED OR NEARLY FLOODED IN THE PAST COUPLE DAYS -- COULD FLOOD AS
WELL. FLOODING ON THESE CASCADE RIVERS WOULD PROBABLY BEGIN TONIGHT
OR FRIDAY. A MAJOR FLOODING EPISODE IS UNLIKELY...BUT IT WOULD BE NO
SURPRISE IF MANY OF THESE RIVERS HAVE MINOR TO MODERATE FLOODING.

THE CASCADES SOUTH OF THE SNOHOMISH BASIN WILL PROBABLY RECEIVE 2 TO
4 INCHES OF RAIN. MOST OF THAT COULD FALL ON FRIDAY AND SOME MODELS
-- ESPECIALLY THE UW WRF-GFS -- SHOW FAIRLY INTENSE RAINFALL IN THAT
AREA. SO THE RIVERS THERE FACE A THREAT OF FLOODING AS WELL. OF
COURSE SOME OF THEM RECENTLY FLOODED...AND THEY ARE ALL RUNNING
HIGH.

THE COLD FRONT SHOULD MOVE SOUTHEAST OF WESTERN WASHINGTON FRIDAY
NIGHT...WITH COLD AND DRIER WEATHER LIKELY THIS WEEKEND. RIVERS
SHOULD THEN RECEDE AND THE FLOOD THREAT WILL END FOR THE FORESEEABLE
FUTURE.   MCDONNAL

&&

.AVIATION...EXPECT RAIN AT TIMES THIS MORNING AS A COLD FRONT PUSHES
THROUGH WESTERN WA. THE FLOW ALOFT IS WESTERLY. MVFR CIGS ARE
POSSIBLE THIS MORNING IN -RA. GUSTY SOUTH WINDS ARE ALSO EXPECTED
WITH THIS FRONT. MOIST WESTERLY FLOW WILL CONTINUE THIS AFTERNOON
WITH SHOWERS MAINLY AFFECTING THE COAST AND MOUNTAINS. RAIN WILL
CONTINUE TONIGHT AS ANOTHER COLD FRONT SHIFTS S/SE INTO WESTERN WA.
33

KSEA...EXPECT LIGHT RAIN AT TIMES TODAY WITH CIGS NEAR 3000 FT.
GUSTY SOUTH WINDS 20015G25KT EXPECTED AT THE TERMINAL THROUGHOUT THE
DAY. 33

&&

.MARINE...A COLD FRONT IS PUSHING THROUGH WESTERN WA EARLY THIS
MORNING WITH MODERATE SOUTH/SOUTHWEST WINDS ACROSS THE WATERS -
SMALL CRAFT ADVISORIES ARE IN EFFECT FOR ALL ZONES. PRESSURE
GRADIENTS WILL REMAIN TIGHT TONIGHT THROUGH FRI MORNING AS ANOTHER
COLD FRONT SHIFTS SOUTH INTO WESTERN WA. STRONG HIGH PRES OVER
INTERIOR B.C. WILL BRING N/NE FRASER RIVER OUTFLOW WINDS LATE FRI
NIGHT INTO SAT WITH GALES POSSIBLE OVER THE NORTHERN INLAND WATERS.
OFFSHORE FLOW WILL PREVAIL SUN AND MON WITH HIGH PRES EAST OF THE
CASCADES. 33

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES AND WARNINGS IN EFFECT FOR PORTIONS OF
      WESTERN WASHINGTON.

PZ...SMALL CRAFT ADVISORY ALL WATERS.
     SMALL CRAFT ADVISORY GRAYS HARBOR BAR FOR ROUGH BAR.

&&

$$

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000
FXUS66 KSEW 270531
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
930 PM PST WED NOV 26 2014

.SYNOPSIS...A FRONT WILL MOVE EAST ACROSS WESTERN WASHINGTON TONIGHT
FOR MORE RAIN AND WINDY CONDITIONS. RAIN WILL CONTINUE ON
THANKSGIVING DAY AS A COLD FRONT APPROACHES FROM THE NORTH THEN
CROSSES THE AREA ON FRIDAY. A COLD UPPER LEVEL TROUGH WILL MOVE
OVER THE AREA FRIDAY NIGHT AND SATURDAY FOR A CHANCE OF
SHOWERS...POSSIBLY MIXED WITH SNOW. COOLER AND DRY NORTHWEST FLOW
ALOFT AND A SURFACE HIGH OVER BRITISH COLUMBIA WILL COMBINE FOR COOL
DRY WEATHER AND MORE SUNSHINE SUNDAY THROUGH EARLY NEXT WEEK.

&&

.SHORT TERM...CURRENT SATELLITE IMAGERY STILL SHOWS IMPENDING FRONT
OFF THE COAST WITH TIMING ON FROPA REMAINING CONSISTENT...HITTING
THE COAST AROUND OR JUST BEFORE MIDNIGHT AND OVER PUGET SOUND BEFORE
12Z/4 AM. OBSERVED WINDS CONTINUING TO RAMP UP IN ADVANCE OF
APPROACHING FRONT...THOUGH NOT QUITE HITTING ANTICIPATED LOW END
ADVISORY SPEEDS JUST YET. SOME LOCATIONS ON THE NORTH COAST AND
AROUND BLI ARE GETTING CLOSE. NO CHANGE IN EXPECTATION FOR WINDS TO
EASE ONCE THE FRONT PASSES LATE TONIGHT. CURRENT RADAR SHOWS
ACTIVITY ALONG THE CASCADES AND IN ADVANCE OF THE FRONT...LEAVING
PUGET SOUND AND EAST PUGET LOWLANDS MOSTLY DRY FOR NOW. WILL EXPECT
THAT HOLE TO FILL IN AS FRONT DRAWS CLOSER.

PICTURE FOR HOLIDAY WEEKEND REMAINS CONSISTENTLY WET. FOLLOWING
FROPA TONIGHT...MAY CATCH A SLIGHT BREAK BEFORE SECOND FRONT MOVES
SLOWLY OVER THE AREA THURSDAY AND INTO FRIDAY...BRINGING CONTINUED
WET CONDITIONS. RAINFALL AMOUNTS EXPECTED OVER THE NEXT 48 HOURS IN
A PERIOD STRETCHING FROM THIS EVENING THROUGH FRIDAY AFTERNOON RANGE
FROM AROUND 1 TO 2 INCHES OF RAINFALL IN THE LOWLANDS AND 3 TO 6
INCHES OF RAINFALL IN THE HIGHER ELEVATIONS OF THE CASCADES AND
OLYMPICS. THE EXCEPTION BEING UP TO 7 INCHES OF RAINFALL AROUND MT.
BAKER. NEEDLESS TO SAY...THIS AMOUNT OF RAINFALL WILL IMPACT RIVERS
THAT HAVE ALREADY HIT FLOOD STAGE TODAY. EVEN THOUGH THESE RIVERS
ARE TRENDING DOWNWARD WITH REGARD TO FLOW/LEVELS...THIS ADDITIONAL
RAINFALL WILL LIKELY BRING ANOTHER PEAK IN FLOW/LEVELS FRIDAY. FOR
FURTHER DETAILS...REFER TO THE HYDROLOGY SECTION BELOW.

MILD TEMPERATURES ARE EXPECTED TO REMAIN IN PLACE FOR THANKSGIVING
BEFORE CONDITIONS BEGIN TO COOL. AN INTERESTING FORECAST CONUNDRUM
ARISES FRIDAY NIGHT INTO SATURDAY. A DIPPING UPPER LEVEL TROUGH WILL
BRING COLDER AIR TO WESTERN WASHINGTON FRIDAY NIGHT...JUST AT THE
TAIL END OF PRECIP EVENT. GFS AND ECMWF INDICATE THAT THINGS MAY
LINE UP JUST ENOUGH FOR MIXED LOWLAND PRECIP FRIDAY NIGHT WITH
LOWLAND SNOW POSSIBLE SATURDAY. HOWEVER...LATEST RUN OF THE WRF GFS
4KM DOES NOT LOOK AS CONVINCING AS THE OTHER TWO MODELS. INHERITED
FORECAST HAS INCLUDED MENTIONS OF MIXED PRECIP AND SNOW FOR THIS
TIME FRAME AND WILL ALLOW FOR FURTHER REEXAMINATION WITH FUTURE
MODEL RUNS. SMR

.LONG TERM...FROM 410 PM DISCUSSION...A STRONG SURFACE HIGH SETTLING
OVER B.C. ON FRIDAY WILL ALLOW COLD FRASER RIVER VALLEY OUTFLOW TO
DEVELOP...BRINGING MORE COLD AIR DRY S OVER W WA. THE AIR MASS WILL
DRY OUT SATURDAY NIGHT WITH TEMPERATURES DROPPING INTO THE 20S
SUNDAY MORNING. SKIES WILL BE MOSTLY SUNNY. THE FRASER VALLEY
OUTFLOW WILL PROBABLY GENERATE ADVISORY LEVEL NE WINDS OVER WHATCOM
AND SAN JUAN COUNTY FRIDAY NIGHT INTO SATURDAY MORNING.

THE ECMWF HAS LEANED MORE CONSISTENTLY THAN THE GFS IN KEEPING A
COOL DRY PATTERN OVER W WA INTO EARLY NEXT WEEK. THE LATEST ECMWF
NOW KEEPS THE PATTERN DRY THROUGH WEDNESDAY ALTHOUGH THERE ARE
SYSTEM THAT GET CLOSE. THE GFS HAD BEEN MORE AGGRESSIVE IN BRINGING
RAIN UP OVER THE ARE FROM THE S...BUT HAS BACKED AWAY FROM THIS ON
THE 12Z AND 18Z RUNS. IT MAY HAVE BEEN PREMATURE...BUT I HAVE DRIED
OUT EARLY NEXT WEEK. CONFIDENCE IS SHAKY BUT HOPE IT STAYS THAT WAY.
KAM

&&

.HYDROLOGY...FROM 410 PM DISCUSSION...A WARM FRONT HELD HEAVIER
RAINFALL NORTH OF THE WA/BRITISH COLUMBIA BORDER TODAY. THIS IS
ALLOWING MOST RIVERS TO SLOWLY RECEDE ACROSS WRN WA. RAIN AMOUNTS UP
TO 5 INCHES SINCE MONDAY IN PLACES LIKE MOUNT RAINIER AND THE
SKYKOMISH-SNOQUALMIE-TOLT-SNOHOMISH BASIN WILL STILL CAUSE SOME
RESIDUAL FLOODING...MAINLY THROUGH THIS EVENING.

ANOTHER FRONT WILL BRING RENEWED RAINFALL TO WRN WA TONIGHT AND
THURSDAY...LOCALLY HEAVY IN THE MOUNTAINS. THE OLYMPICS AND NORTH
CASCADES WILL RECEIVE THE HEAVIEST RAINFALL WITH 2 TO 4 INCHES OF
RAIN EXPECTED. 1 TO 2 INCHES MAY FALL IN THE CENTRAL CASCADES. THE
SNOW LEVEL WILL BE NEAR 7000 FEET.

A SECONDARY SURGE OF MOISTURE WILL ARRIVE THURSDAY NIGHT INTO
FRIDAY. MODELS VARY MUCH MORE ON THE DISTRIBUTION AND POTENTIAL
RAINFALL AMOUNTS WITH THIS SECOND FRONTAL SYSTEM. IN
GENERAL...HEAVIER RAIN AMOUNTS THURSDAY NIGHT AND FRIDAY SHOULD
OCCUR ALONG S/SW FACING SLOPES OF THE OLYMPICS AND N
CASCADES...ALTHOUGH THE CENTRAL CASCADES COULD ALSO SEE HEAVY
PRECIPITATION BY FRIDAY. ADDITIONAL AMOUNTS OF 2 TO 3 INCHES ARE
POSSIBLE. THIS MEANS THE 36-48 HOUR RAINFALL TOTALS FOR THE OLYMPICS
AND CASCADES MAY REACH 4 TO 7 INCHES WITH LOCALLY HIGHER
AMOUNTS...ESPECIALLY IN THE N CASCADES.

THESE AMOUNTS WILL LIKELY DRIVE SEVERAL RIVERS TO FLOOD...ALTHOUGH
WIDESPREAD MAJOR FLOODING APPEARS UNLIKELY. AT HIGHEST RISK FOR
FLOODING IS THE SKOKOMISH RIVER IN THE OLYMPICS...THE NOOKSACK AND
SKAGIT RIVERS IN THE NORTH...AND THE
STILLAGUAMISH...SNOQUALMIE...AND TOLT ACROSS CENTRAL AREAS. IF THE
HEAVIER RAIN SHIFTS FAR ENOUGH SOUTH THEN FLOODING COULD BE POSSIBLE
ON THE DESCHUTES RIVER AND THE REACH OF THE SKOOKUMCHUCK RIVER NEAR
BUCODA IN THURSTON COUNTY.

A FLOOD WATCH REMAINS IN EFFECT THROUGH FRIDAY...WHICH INCLUDES ALL
THE COUNTIES WITH RIVERS FLOWING OFF THE WEST SLOPES OF THE CASCADES
AND MASON COUNTY FOR THE POSSIBILITY OF A FLOOD ON THE SKOKOMISH.

COLDER AND DRIER WEATHER IS LIKELY THIS WEEKEND...SO RIVERS SHOULD
RECEDE AND THE FLOOD THREAT WILL END FOR THE FORESEEABLE FUTURE.

MERCER

&&

.AVIATION...RAIN IN INCREASE IN COVERAGE ACROSS WESTERN WA TONIGHT
AS A COLD FRONT MOVES INLAND. THE FLOW ALOFT IS WESTERLY. CIGS ARE
MAINLY VFR THIS EVENING BUT SHOULD LOWER INTO MVFR RANGE OVERNIGHT.
GUSTY SOUTH WINDS ARE ALSO EXPECTED WITH THE FRONT...ESPECIALLY
ALONG THE COAST AND NORTH INTERIOR. MOIST WESTERLY FLOW WILL
CONTINUE ON THURSDAY WITH SHOWERS MAINLY AFFECTING THE COAST AND
MOUNTAINS. 33

KSEA...EXPECT RAIN AT TIMES TONIGHT WITH CIGS LOWERING TO MVFR
RANGE. GUSTY SOUTH WINDS 20015G25KT EXPECTED AT THE TERMINAL
THROUGHOUT THE NIGHT. 33

&&

.MARINE...A COLD FRONT WILL SHIFT INLAND TONIGHT WITH INCREASING
SOUTH WINDS OVER THE WATERS. GALE WARNINGS REMAIN IN EFFECT FOR THE
COASTAL WATERS...ENTRANCES TO THE STRAIT OF JUAN DE FUCA AND THE
NORTHERN INLAND WATERS. A GALE WARNING WAS ALSO ISSUED FOR ADMIRALTY
INLET. WINDS WILL EASE OVERNIGHT BUT WILL STILL SEE SMALL CRAFT
ADVISORY WINDS ACROSS THE WATERS. PRESSURE GRADIENTS WILL REMAIN
TIGHT THU NIGHT THROUGH FRI AS ANOTHER COLD FRONT PUSHES SOUTH FROM
B.C. STRONG HIGH PRES OVER INTERIOR B.C. WILL BRING N/NE FRASER
RIVER OUTFLOW WINDS LATE FRI NIGHT INTO SAT. OFFSHORE FLOW WILL
PREVAIL SUN AND MON WITH HIGH PRES EAST OF THE CASCADES. 33

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES AND WARNINGS IN EFFECT FOR PORTIONS OF
     WESTERN WASHINGTON.
     WIND ADVISORY NORTH COAST...WESTERN WHATCOM...SAN
     JUANS...ADMIRALTY INLET AREA.

PZ...SMALL CRAFT ADVISORY ALL WATERS.
    .SMALL CRAFT ADVISORY GRAYS HARBOR BAR FOR ROUGH BAR.
    .GALE WARNING COASTAL WATERS...ENTRANCES STRAIT OF JUAN DE
     FUCA...NORTHERN INLAND WATERS...ADMIRALTY INLET.

&&

$$

WWW.WEATHER.GOV/SEATTLE

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000
FXUS66 KSEW 270531
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
930 PM PST WED NOV 26 2014

.SYNOPSIS...A FRONT WILL MOVE EAST ACROSS WESTERN WASHINGTON TONIGHT
FOR MORE RAIN AND WINDY CONDITIONS. RAIN WILL CONTINUE ON
THANKSGIVING DAY AS A COLD FRONT APPROACHES FROM THE NORTH THEN
CROSSES THE AREA ON FRIDAY. A COLD UPPER LEVEL TROUGH WILL MOVE
OVER THE AREA FRIDAY NIGHT AND SATURDAY FOR A CHANCE OF
SHOWERS...POSSIBLY MIXED WITH SNOW. COOLER AND DRY NORTHWEST FLOW
ALOFT AND A SURFACE HIGH OVER BRITISH COLUMBIA WILL COMBINE FOR COOL
DRY WEATHER AND MORE SUNSHINE SUNDAY THROUGH EARLY NEXT WEEK.

&&

.SHORT TERM...CURRENT SATELLITE IMAGERY STILL SHOWS IMPENDING FRONT
OFF THE COAST WITH TIMING ON FROPA REMAINING CONSISTENT...HITTING
THE COAST AROUND OR JUST BEFORE MIDNIGHT AND OVER PUGET SOUND BEFORE
12Z/4 AM. OBSERVED WINDS CONTINUING TO RAMP UP IN ADVANCE OF
APPROACHING FRONT...THOUGH NOT QUITE HITTING ANTICIPATED LOW END
ADVISORY SPEEDS JUST YET. SOME LOCATIONS ON THE NORTH COAST AND
AROUND BLI ARE GETTING CLOSE. NO CHANGE IN EXPECTATION FOR WINDS TO
EASE ONCE THE FRONT PASSES LATE TONIGHT. CURRENT RADAR SHOWS
ACTIVITY ALONG THE CASCADES AND IN ADVANCE OF THE FRONT...LEAVING
PUGET SOUND AND EAST PUGET LOWLANDS MOSTLY DRY FOR NOW. WILL EXPECT
THAT HOLE TO FILL IN AS FRONT DRAWS CLOSER.

PICTURE FOR HOLIDAY WEEKEND REMAINS CONSISTENTLY WET. FOLLOWING
FROPA TONIGHT...MAY CATCH A SLIGHT BREAK BEFORE SECOND FRONT MOVES
SLOWLY OVER THE AREA THURSDAY AND INTO FRIDAY...BRINGING CONTINUED
WET CONDITIONS. RAINFALL AMOUNTS EXPECTED OVER THE NEXT 48 HOURS IN
A PERIOD STRETCHING FROM THIS EVENING THROUGH FRIDAY AFTERNOON RANGE
FROM AROUND 1 TO 2 INCHES OF RAINFALL IN THE LOWLANDS AND 3 TO 6
INCHES OF RAINFALL IN THE HIGHER ELEVATIONS OF THE CASCADES AND
OLYMPICS. THE EXCEPTION BEING UP TO 7 INCHES OF RAINFALL AROUND MT.
BAKER. NEEDLESS TO SAY...THIS AMOUNT OF RAINFALL WILL IMPACT RIVERS
THAT HAVE ALREADY HIT FLOOD STAGE TODAY. EVEN THOUGH THESE RIVERS
ARE TRENDING DOWNWARD WITH REGARD TO FLOW/LEVELS...THIS ADDITIONAL
RAINFALL WILL LIKELY BRING ANOTHER PEAK IN FLOW/LEVELS FRIDAY. FOR
FURTHER DETAILS...REFER TO THE HYDROLOGY SECTION BELOW.

MILD TEMPERATURES ARE EXPECTED TO REMAIN IN PLACE FOR THANKSGIVING
BEFORE CONDITIONS BEGIN TO COOL. AN INTERESTING FORECAST CONUNDRUM
ARISES FRIDAY NIGHT INTO SATURDAY. A DIPPING UPPER LEVEL TROUGH WILL
BRING COLDER AIR TO WESTERN WASHINGTON FRIDAY NIGHT...JUST AT THE
TAIL END OF PRECIP EVENT. GFS AND ECMWF INDICATE THAT THINGS MAY
LINE UP JUST ENOUGH FOR MIXED LOWLAND PRECIP FRIDAY NIGHT WITH
LOWLAND SNOW POSSIBLE SATURDAY. HOWEVER...LATEST RUN OF THE WRF GFS
4KM DOES NOT LOOK AS CONVINCING AS THE OTHER TWO MODELS. INHERITED
FORECAST HAS INCLUDED MENTIONS OF MIXED PRECIP AND SNOW FOR THIS
TIME FRAME AND WILL ALLOW FOR FURTHER REEXAMINATION WITH FUTURE
MODEL RUNS. SMR

.LONG TERM...FROM 410 PM DISCUSSION...A STRONG SURFACE HIGH SETTLING
OVER B.C. ON FRIDAY WILL ALLOW COLD FRASER RIVER VALLEY OUTFLOW TO
DEVELOP...BRINGING MORE COLD AIR DRY S OVER W WA. THE AIR MASS WILL
DRY OUT SATURDAY NIGHT WITH TEMPERATURES DROPPING INTO THE 20S
SUNDAY MORNING. SKIES WILL BE MOSTLY SUNNY. THE FRASER VALLEY
OUTFLOW WILL PROBABLY GENERATE ADVISORY LEVEL NE WINDS OVER WHATCOM
AND SAN JUAN COUNTY FRIDAY NIGHT INTO SATURDAY MORNING.

THE ECMWF HAS LEANED MORE CONSISTENTLY THAN THE GFS IN KEEPING A
COOL DRY PATTERN OVER W WA INTO EARLY NEXT WEEK. THE LATEST ECMWF
NOW KEEPS THE PATTERN DRY THROUGH WEDNESDAY ALTHOUGH THERE ARE
SYSTEM THAT GET CLOSE. THE GFS HAD BEEN MORE AGGRESSIVE IN BRINGING
RAIN UP OVER THE ARE FROM THE S...BUT HAS BACKED AWAY FROM THIS ON
THE 12Z AND 18Z RUNS. IT MAY HAVE BEEN PREMATURE...BUT I HAVE DRIED
OUT EARLY NEXT WEEK. CONFIDENCE IS SHAKY BUT HOPE IT STAYS THAT WAY.
KAM

&&

.HYDROLOGY...FROM 410 PM DISCUSSION...A WARM FRONT HELD HEAVIER
RAINFALL NORTH OF THE WA/BRITISH COLUMBIA BORDER TODAY. THIS IS
ALLOWING MOST RIVERS TO SLOWLY RECEDE ACROSS WRN WA. RAIN AMOUNTS UP
TO 5 INCHES SINCE MONDAY IN PLACES LIKE MOUNT RAINIER AND THE
SKYKOMISH-SNOQUALMIE-TOLT-SNOHOMISH BASIN WILL STILL CAUSE SOME
RESIDUAL FLOODING...MAINLY THROUGH THIS EVENING.

ANOTHER FRONT WILL BRING RENEWED RAINFALL TO WRN WA TONIGHT AND
THURSDAY...LOCALLY HEAVY IN THE MOUNTAINS. THE OLYMPICS AND NORTH
CASCADES WILL RECEIVE THE HEAVIEST RAINFALL WITH 2 TO 4 INCHES OF
RAIN EXPECTED. 1 TO 2 INCHES MAY FALL IN THE CENTRAL CASCADES. THE
SNOW LEVEL WILL BE NEAR 7000 FEET.

A SECONDARY SURGE OF MOISTURE WILL ARRIVE THURSDAY NIGHT INTO
FRIDAY. MODELS VARY MUCH MORE ON THE DISTRIBUTION AND POTENTIAL
RAINFALL AMOUNTS WITH THIS SECOND FRONTAL SYSTEM. IN
GENERAL...HEAVIER RAIN AMOUNTS THURSDAY NIGHT AND FRIDAY SHOULD
OCCUR ALONG S/SW FACING SLOPES OF THE OLYMPICS AND N
CASCADES...ALTHOUGH THE CENTRAL CASCADES COULD ALSO SEE HEAVY
PRECIPITATION BY FRIDAY. ADDITIONAL AMOUNTS OF 2 TO 3 INCHES ARE
POSSIBLE. THIS MEANS THE 36-48 HOUR RAINFALL TOTALS FOR THE OLYMPICS
AND CASCADES MAY REACH 4 TO 7 INCHES WITH LOCALLY HIGHER
AMOUNTS...ESPECIALLY IN THE N CASCADES.

THESE AMOUNTS WILL LIKELY DRIVE SEVERAL RIVERS TO FLOOD...ALTHOUGH
WIDESPREAD MAJOR FLOODING APPEARS UNLIKELY. AT HIGHEST RISK FOR
FLOODING IS THE SKOKOMISH RIVER IN THE OLYMPICS...THE NOOKSACK AND
SKAGIT RIVERS IN THE NORTH...AND THE
STILLAGUAMISH...SNOQUALMIE...AND TOLT ACROSS CENTRAL AREAS. IF THE
HEAVIER RAIN SHIFTS FAR ENOUGH SOUTH THEN FLOODING COULD BE POSSIBLE
ON THE DESCHUTES RIVER AND THE REACH OF THE SKOOKUMCHUCK RIVER NEAR
BUCODA IN THURSTON COUNTY.

A FLOOD WATCH REMAINS IN EFFECT THROUGH FRIDAY...WHICH INCLUDES ALL
THE COUNTIES WITH RIVERS FLOWING OFF THE WEST SLOPES OF THE CASCADES
AND MASON COUNTY FOR THE POSSIBILITY OF A FLOOD ON THE SKOKOMISH.

COLDER AND DRIER WEATHER IS LIKELY THIS WEEKEND...SO RIVERS SHOULD
RECEDE AND THE FLOOD THREAT WILL END FOR THE FORESEEABLE FUTURE.

MERCER

&&

.AVIATION...RAIN IN INCREASE IN COVERAGE ACROSS WESTERN WA TONIGHT
AS A COLD FRONT MOVES INLAND. THE FLOW ALOFT IS WESTERLY. CIGS ARE
MAINLY VFR THIS EVENING BUT SHOULD LOWER INTO MVFR RANGE OVERNIGHT.
GUSTY SOUTH WINDS ARE ALSO EXPECTED WITH THE FRONT...ESPECIALLY
ALONG THE COAST AND NORTH INTERIOR. MOIST WESTERLY FLOW WILL
CONTINUE ON THURSDAY WITH SHOWERS MAINLY AFFECTING THE COAST AND
MOUNTAINS. 33

KSEA...EXPECT RAIN AT TIMES TONIGHT WITH CIGS LOWERING TO MVFR
RANGE. GUSTY SOUTH WINDS 20015G25KT EXPECTED AT THE TERMINAL
THROUGHOUT THE NIGHT. 33

&&

.MARINE...A COLD FRONT WILL SHIFT INLAND TONIGHT WITH INCREASING
SOUTH WINDS OVER THE WATERS. GALE WARNINGS REMAIN IN EFFECT FOR THE
COASTAL WATERS...ENTRANCES TO THE STRAIT OF JUAN DE FUCA AND THE
NORTHERN INLAND WATERS. A GALE WARNING WAS ALSO ISSUED FOR ADMIRALTY
INLET. WINDS WILL EASE OVERNIGHT BUT WILL STILL SEE SMALL CRAFT
ADVISORY WINDS ACROSS THE WATERS. PRESSURE GRADIENTS WILL REMAIN
TIGHT THU NIGHT THROUGH FRI AS ANOTHER COLD FRONT PUSHES SOUTH FROM
B.C. STRONG HIGH PRES OVER INTERIOR B.C. WILL BRING N/NE FRASER
RIVER OUTFLOW WINDS LATE FRI NIGHT INTO SAT. OFFSHORE FLOW WILL
PREVAIL SUN AND MON WITH HIGH PRES EAST OF THE CASCADES. 33

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES AND WARNINGS IN EFFECT FOR PORTIONS OF
     WESTERN WASHINGTON.
     WIND ADVISORY NORTH COAST...WESTERN WHATCOM...SAN
     JUANS...ADMIRALTY INLET AREA.

PZ...SMALL CRAFT ADVISORY ALL WATERS.
    .SMALL CRAFT ADVISORY GRAYS HARBOR BAR FOR ROUGH BAR.
    .GALE WARNING COASTAL WATERS...ENTRANCES STRAIT OF JUAN DE
     FUCA...NORTHERN INLAND WATERS...ADMIRALTY INLET.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML








000
FXUS66 KSEW 270011
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
410 PM PST WED NOV 26 2014

.SYNOPSIS...A FRONT WILL MOVE EAST ACROSS WESTERN WASHINGTON TONIGHT
FOR MORE RAIN AND WINDY CONDITIONS. RAIN WILL CONTINUE ON
THANKSGIVING DAY AS A COLD FRONT APPROACHES FROM THE NORTH THEN
CROSSES THE AREA ON FRIDAY. A COLD UPPER LEVEL TROUGH WILL MOVE
OVER THE AREA FRIDAY NIGHT AND SATURDAY FOR A CHANCE OF
SHOWERS...POSSIBLY MIXED WITH SNOW. COOLER AND DRY NORTHWEST FLOW
ALOFT AND A SURFACE HIGH OVER BRITISH COLUMBIA WILL COMBINE FOR COOL
DRY WEATHER AND MORE SUNSHINE SUNDAY THROUGH EARLY NEXT WEEK.

&&

.SHORT TERM...IR IMAGERY SHOWS THE FRONT OFFSHORE ALONG 130W AT 23Z
MOVING STEADILY TOWARD THE COAST. MODELS SEEM TO HAVE A GOOD HANDLE
ON THIS SYSTEM...WITH FROPA ON THE COAST AROUND MIDNIGHT AND OVER
PUGET SOUND BEFORE BEFORE 12Z/4 AM. SE PRESSURE GRADIENTS WILL
INCREASE THIS EVENING AHEAD OF THE FRONT AND LOW END WIND ADVISORY
WINDS 20-35G45 MPH MAY DEVELOP OVER THE N COAST AND PARTS OF THE N
INTERIOR. WINDS WILL EASE BEHIND THE FRONT LATE TONIGHT.

THE FRONT WILL ALSO RAISE STRONG SW LOW LEVEL WINDS OF 35-45 KT
AROUND 850 MB WHICH SHOULD BRING HEAVY OROGRAPHIC RAIN TO THE
OLYMPICS AND N CASCADES. AFTER A BRIEF LULL BEHIND TONIGHTS
FRONT...A COLD FRONT WILL MOVE S ALONG THE B.C. COAST BRINGING RAIN
AT TIMES TO W WA AHEAD OF IT THROUGH THANKSGIVING. THE COLD FRONT
WILL MOVE SLOWLY ACROSS W WA ON FRIDAY. THIS COLD FRONT IS ACTUALLY
THE OLD WARM FRONT THAT STALLED OVER SOUTHERN B.C. TODAY. A STRONG
COLD UPPER LEVEL SHORTWAVE TROUGH MOVING DOWN THE B.C. COAST WILL
SHOVE THE BAROCLINIC BAND BACK SOUTHWARD AND ACROSS W WA AS A COLD
FRONT.

SW LOW LEVEL FLOW WILL BECOME STRONG AGAIN AS THE COLD FRONT
APPROACHES THE AREA ON THURSDAY...EXTENDING THE PERIOD OF HEAVY
OROGRAPHIC RAIN OVER THE MOUNTAINS INTO FRIDAY. THE HEAVY RAIN WILL
EASE OFF FROM THE NORTH AS THE FRONT MOVES THROUGH. 48 HOUR RAINFALL
AMOUNTS FROM 00Z THURSDAY/WED AFTERNOON THROUGH 00Z SATURDAY/FRIDAY
AFTERNOON...WILL BE AROUND 4 INCHES FOR THE OLYMPICS AND 3-4.5
INCHES FOR THE NORTH CASCADES...EXCEPT FOR A BULLSEYE AROUND 6
INCHES AROUND MT BAKER. THIS MAY BRING SOME OF THE RIVERS FLOWING
OFF THE N CASCADES AND POSSIBLY PARTS OF THE CENTRAL CASCADES TO
FLOOD STAGE THURSDAY NIGHT INTO FRIDAY. SEE THE HYDROLOGY SECTION
BELOW FOR MORE DETAILS.

THE MILD AIR MASS OVER THE AREA WILL RESULT IN TEMPERATURES IN THE
50S.

ONCE THE FRONT MOVES THROUGH ON FRIDAY...THE COLD UPPER LEVEL TROUGH
WILL MOVE OVERHEAD. THE AIR MASS WILL COOL ENOUGH SO THAT SNOW
LEVELS OVER THE LOWLAND LOWER TO 500-1000 FEET LATE FRIDAY NIGHT.
RESIDUAL MOISTURE FROM THE COLD FRONT WILL REMAIN OVER THE AREA AND
THE TROUGH WILL PROVIDE SOME INSTABILITY AND LIFT. A PUGET SOUND
CONVERGENCE ZONE WILL LIKELY SET UP FRIDAY NIGHT AND EXTEND INTO
SATURDAY MORNING. SOME LIGHT SNOW IS POSSIBLE LATE FRIDAY NIGHT OVER
THE N INTERIOR...OVER THE INTERIOR AREAS OF THE N COAST AND WESTERN
STRAIT...NEAR THE CASCADES AND POSSIBLY IN THE CONVERGENCE ZONE.
SNOW LEVELS WILL LOWER TO 500-1000 FEET IN THESE AREAS. SNOW LEVELS
WILL LOWER TO BELOW 500 FEET THROUGHOUT W WA SATURDAY MORNING. WITH
THE TROUGH STILL OVERHEAD THERE WILL BE A CHANCE OF SNOW SHOWERS.
SNOW ACCUMULATIONS WILL BE LESS THAN AN INCH...BUT THERE IS ALWAYS A
CHANCE FOR A LITTLE MORE IN A CONVERGENCE ZONE. KAM

.LONG TERM...A STRONG SURFACE HIGH SETTLING OVER B.C. ON FRIDAY WILL
ALLOW COLD FRASER RIVER VALLEY OUTFLOW TO DEVELOP...BRINGING MORE
COLD AIR DRY S OVER W WA. THE AIR MASS WILL DRY OUT SATURDAY NIGHT
WITH TEMPERATURES DROPPING INTO THE 20S SUNDAY MORNING. SKIES WILL
BE MOSTLY SUNNY. THE FRASER VALLEY OUTFLOW WILL PROBABLY GENERATE
ADVISORY LEVEL NE WINDS OVER WHATCOM AND SAN JUAN COUNTY FRIDAY
NIGHT INTO SATURDAY MORNING.

THE ECMWF HAS LEANED MORE CONSISTENTLY THAN THE GFS IN KEEPING A
COOL DRY PATTERN OVER W WA INTO EARLY NEXT WEEK. THE LATEST ECMWF
NOW KEEPS THE PATTERN DRY THROUGH WEDNESDAY ALTHOUGH THERE ARE
SYSTEM THAT GET CLOSE. THE GFS HAD BEEN MORE AGGRESSIVE IN BRINGING
RAIN UP OVER THE ARE FROM THE S...BUT HAS BACKED AWAY FROM THIS ON
THE 12Z AND 18Z RUNS. IT MAY HAVE BEEN PREMATURE...BUT I HAVE DRIED
OUT EARLY NEXT WEEK. CONFIDENCE IS SHAKY BUT HOPE IT STAYS THAT WAY.
KAM

&&

.HYDROLOGY...A WARM FRONT HELD HEAVIER RAINFALL NORTH OF THE
WA/BRITISH COLUMBIA BORDER TODAY. THIS IS ALLOWING MOST RIVERS TO
SLOWLY RECEDE ACROSS WRN WA. RAIN AMOUNTS UP TO 5 INCHES SINCE
MONDAY IN PLACES LIKE MOUNT RAINIER AND THE
SKYKOMISH-SNOQUALMIE-TOLT-SNOHOMISH BASIN WILL STILL CAUSE SOME
RESIDUAL FLOODING...MAINLY THROUGH THIS EVENING.

ANOTHER FRONT WILL BRING RENEWED RAINFALL TO WRN WA TONIGHT AND
THURSDAY...LOCALLY HEAVY IN THE MOUNTAINS. THE OLYMPICS AND NORTH
CASCADES WILL RECEIVE THE HEAVIEST RAINFALL WITH 2 TO 4 INCHES OF
RAIN EXPECTED. 1 TO 2 INCHES MAY FALL IN THE CENTRAL CASCADES. THE
SNOW LEVEL WILL BE NEAR 7000 FEET.

A SECONDARY SURGE OF MOISTURE WILL ARRIVE THURSDAY NIGHT INTO
FRIDAY. MODELS VARY MUCH MORE ON THE DISTRIBUTION AND POTENTIAL
RAINFALL AMOUNTS WITH THIS SECOND FRONTAL SYSTEM. IN
GENERAL...HEAVIER RAIN AMOUNTS THURSDAY NIGHT AND FRIDAY SHOULD
OCCUR ALONG S/SW FACING SLOPES OF THE OLYMPICS AND N
CASCADES...ALTHOUGH THE CENTRAL CASCADES COULD ALSO SEE HEAVY
PRECIPITATION BY FRIDAY. ADDITIONAL AMOUNTS OF 2 TO 3 INCHES ARE
POSSIBLE. THIS MEANS THE 36-48 HOUR RAINFALL TOTALS FOR THE OLYMPICS
AND CASCADES MAY REACH 4 TO 7 INCHES WITH LOCALLY HIGHER
AMOUNTS...ESPECIALLY IN THE N CASCADES.

THESE AMOUNTS WILL LIKELY DRIVE SEVERAL RIVERS TO FLOOD...ALTHOUGH
WIDESPREAD MAJOR FLOODING APPEARS UNLIKELY. AT HIGHEST RISK FOR
FLOODING IS THE SKOKOMISH RIVER IN THE OLYMPICS...THE NOOKSACK AND
SKAGIT RIVERS IN THE NORTH...AND THE
STILLAGUAMISH...SNOQUALMIE...AND TOLT ACROSS CENTRAL AREAS. IF THE
HEAVIER RAIN SHIFTS FAR ENOUGH SOUTH THEN FLOODING COULD BE POSSIBLE
ON THE DESCHUTES RIVER AND THE REACH OF THE SKOOKUMCHUCK RIVER NEAR
BUCODA IN THURSTON COUNTY.

A FLOOD WATCH REMAINS IN EFFECT THROUGH FRIDAY...WHICH INCLUDES ALL
THE COUNTIES WITH RIVERS FLOWING OFF THE WEST SLOPES OF THE CASCADES
AND MASON COUNTY FOR THE POSSIBILITY OF A FLOOD ON THE SKOKOMISH.

COLDER AND DRIER WEATHER IS LIKELY THIS WEEKEND...SO RIVERS SHOULD
RECEDE AND THE FLOOD THREAT WILL END FOR THE FORESEEABLE FUTURE.

MERCER

&&

.AVIATION...THE FLOW ALOFT IS STRONG AND FROM THE WEST SOUTHWEST.
THE AIR MASS IS RATHER MOIST AND RELATIVELY STABLE AFTER THE PASSAGE
OF A WARM FRONT. CIGS ARE CURRENTLY MVFR TO VFR ACROSS THE AREA. A
COLD FRONT IS TIMED TO MOVE THROUGH THE AREA OVERNIGHT TONIGHT AND
DESTABILIZE THINGS...CIGS MAY RISE A BIT BEFORE THE FRONT PASSES
THROUGH...BUT THEN CIGS WILL DETERIORATE AFTERWARDS TO IFR OR MVFR.
SLY SURFACE WINDS WILL BE STRONG AND GUSTY WITH THE FRONT AND INTO
THE DAY THURSDAY.

KSEA...SOUTH WIND INCREASING TO 12 TO 14 KT OVERNIGHT WITH GUSTS TO
20 KT DURING AND AFTER FRONTAL PASSAGE AROUND 7 TO 9Z. CIGS WILL
CHANGE FROM VFR TO MVFR SHORTLY AFTER THE FRONTAL PASSAGE AS A LOWER
DECK OF CLOUDS MOVES IN. JSMITH

&&

.MARINE...A COLD FRONT WILL MOVE ONSHORE TONIGHT. GALE WARNINGS HAVE
BEEN ISSUED TONIGHT FOR THE COAST...ENTRANCES TO THE STRAIT...AND
NORTHERN INLAND WATERS AS THEY ARE MOST PRONE TO STRONG SOUTHERLY
WINDS THAT THE FRONT WILL BRING. MODERATE TO STRONG ONSHORE AND
SOUTHERLY FLOW WILL PREVAIL BEHIND THE FRONT ON THURSDAY...AND SMALL
CRAFT ADVISORIES HAVE BEEN ISSUED FOR MOST OF THE WATERS THROUGH
THURSDAY NIGHT.

ANOTHER COLD FRONT WILL MOVE THROUGH THE WATERS EARLY FRIDAY. THIS
FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND MODERATE NORTHERLY WINDS OVER THE OTHER WATERS
LATER FRIDAY INTO SATURDAY. MODERATE OFFSHORE FLOW IS LIKELY SUNDAY
INTO MONDAY WITH HIGHER SEA LEVEL PRESSURE INLAND AND LOWER PRESSURE
OVER THE SOUTHERN COASTAL WATERS. JSMITH

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES AND WARNINGS ARE IN EFFECT FOR PORTIONS OF
      WESTERN WASHINGTON.
     WIND ADVISORY N COAST AND PARTS OF N INTERIOR TONIGHT.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
    .SMALL CRAFT ADVISORY GRAYS HARBOR BAR FOR ROUGH BAR.
    .GALE WARNING COASTAL WATERS...ENTRANCES STRAIT OF JUAN DE
     FUCA...AND NORTHERN INLAND WATERS.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML













000
FXUS66 KSEW 270011
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
410 PM PST WED NOV 26 2014

.SYNOPSIS...A FRONT WILL MOVE EAST ACROSS WESTERN WASHINGTON TONIGHT
FOR MORE RAIN AND WINDY CONDITIONS. RAIN WILL CONTINUE ON
THANKSGIVING DAY AS A COLD FRONT APPROACHES FROM THE NORTH THEN
CROSSES THE AREA ON FRIDAY. A COLD UPPER LEVEL TROUGH WILL MOVE
OVER THE AREA FRIDAY NIGHT AND SATURDAY FOR A CHANCE OF
SHOWERS...POSSIBLY MIXED WITH SNOW. COOLER AND DRY NORTHWEST FLOW
ALOFT AND A SURFACE HIGH OVER BRITISH COLUMBIA WILL COMBINE FOR COOL
DRY WEATHER AND MORE SUNSHINE SUNDAY THROUGH EARLY NEXT WEEK.

&&

.SHORT TERM...IR IMAGERY SHOWS THE FRONT OFFSHORE ALONG 130W AT 23Z
MOVING STEADILY TOWARD THE COAST. MODELS SEEM TO HAVE A GOOD HANDLE
ON THIS SYSTEM...WITH FROPA ON THE COAST AROUND MIDNIGHT AND OVER
PUGET SOUND BEFORE BEFORE 12Z/4 AM. SE PRESSURE GRADIENTS WILL
INCREASE THIS EVENING AHEAD OF THE FRONT AND LOW END WIND ADVISORY
WINDS 20-35G45 MPH MAY DEVELOP OVER THE N COAST AND PARTS OF THE N
INTERIOR. WINDS WILL EASE BEHIND THE FRONT LATE TONIGHT.

THE FRONT WILL ALSO RAISE STRONG SW LOW LEVEL WINDS OF 35-45 KT
AROUND 850 MB WHICH SHOULD BRING HEAVY OROGRAPHIC RAIN TO THE
OLYMPICS AND N CASCADES. AFTER A BRIEF LULL BEHIND TONIGHTS
FRONT...A COLD FRONT WILL MOVE S ALONG THE B.C. COAST BRINGING RAIN
AT TIMES TO W WA AHEAD OF IT THROUGH THANKSGIVING. THE COLD FRONT
WILL MOVE SLOWLY ACROSS W WA ON FRIDAY. THIS COLD FRONT IS ACTUALLY
THE OLD WARM FRONT THAT STALLED OVER SOUTHERN B.C. TODAY. A STRONG
COLD UPPER LEVEL SHORTWAVE TROUGH MOVING DOWN THE B.C. COAST WILL
SHOVE THE BAROCLINIC BAND BACK SOUTHWARD AND ACROSS W WA AS A COLD
FRONT.

SW LOW LEVEL FLOW WILL BECOME STRONG AGAIN AS THE COLD FRONT
APPROACHES THE AREA ON THURSDAY...EXTENDING THE PERIOD OF HEAVY
OROGRAPHIC RAIN OVER THE MOUNTAINS INTO FRIDAY. THE HEAVY RAIN WILL
EASE OFF FROM THE NORTH AS THE FRONT MOVES THROUGH. 48 HOUR RAINFALL
AMOUNTS FROM 00Z THURSDAY/WED AFTERNOON THROUGH 00Z SATURDAY/FRIDAY
AFTERNOON...WILL BE AROUND 4 INCHES FOR THE OLYMPICS AND 3-4.5
INCHES FOR THE NORTH CASCADES...EXCEPT FOR A BULLSEYE AROUND 6
INCHES AROUND MT BAKER. THIS MAY BRING SOME OF THE RIVERS FLOWING
OFF THE N CASCADES AND POSSIBLY PARTS OF THE CENTRAL CASCADES TO
FLOOD STAGE THURSDAY NIGHT INTO FRIDAY. SEE THE HYDROLOGY SECTION
BELOW FOR MORE DETAILS.

THE MILD AIR MASS OVER THE AREA WILL RESULT IN TEMPERATURES IN THE
50S.

ONCE THE FRONT MOVES THROUGH ON FRIDAY...THE COLD UPPER LEVEL TROUGH
WILL MOVE OVERHEAD. THE AIR MASS WILL COOL ENOUGH SO THAT SNOW
LEVELS OVER THE LOWLAND LOWER TO 500-1000 FEET LATE FRIDAY NIGHT.
RESIDUAL MOISTURE FROM THE COLD FRONT WILL REMAIN OVER THE AREA AND
THE TROUGH WILL PROVIDE SOME INSTABILITY AND LIFT. A PUGET SOUND
CONVERGENCE ZONE WILL LIKELY SET UP FRIDAY NIGHT AND EXTEND INTO
SATURDAY MORNING. SOME LIGHT SNOW IS POSSIBLE LATE FRIDAY NIGHT OVER
THE N INTERIOR...OVER THE INTERIOR AREAS OF THE N COAST AND WESTERN
STRAIT...NEAR THE CASCADES AND POSSIBLY IN THE CONVERGENCE ZONE.
SNOW LEVELS WILL LOWER TO 500-1000 FEET IN THESE AREAS. SNOW LEVELS
WILL LOWER TO BELOW 500 FEET THROUGHOUT W WA SATURDAY MORNING. WITH
THE TROUGH STILL OVERHEAD THERE WILL BE A CHANCE OF SNOW SHOWERS.
SNOW ACCUMULATIONS WILL BE LESS THAN AN INCH...BUT THERE IS ALWAYS A
CHANCE FOR A LITTLE MORE IN A CONVERGENCE ZONE. KAM

.LONG TERM...A STRONG SURFACE HIGH SETTLING OVER B.C. ON FRIDAY WILL
ALLOW COLD FRASER RIVER VALLEY OUTFLOW TO DEVELOP...BRINGING MORE
COLD AIR DRY S OVER W WA. THE AIR MASS WILL DRY OUT SATURDAY NIGHT
WITH TEMPERATURES DROPPING INTO THE 20S SUNDAY MORNING. SKIES WILL
BE MOSTLY SUNNY. THE FRASER VALLEY OUTFLOW WILL PROBABLY GENERATE
ADVISORY LEVEL NE WINDS OVER WHATCOM AND SAN JUAN COUNTY FRIDAY
NIGHT INTO SATURDAY MORNING.

THE ECMWF HAS LEANED MORE CONSISTENTLY THAN THE GFS IN KEEPING A
COOL DRY PATTERN OVER W WA INTO EARLY NEXT WEEK. THE LATEST ECMWF
NOW KEEPS THE PATTERN DRY THROUGH WEDNESDAY ALTHOUGH THERE ARE
SYSTEM THAT GET CLOSE. THE GFS HAD BEEN MORE AGGRESSIVE IN BRINGING
RAIN UP OVER THE ARE FROM THE S...BUT HAS BACKED AWAY FROM THIS ON
THE 12Z AND 18Z RUNS. IT MAY HAVE BEEN PREMATURE...BUT I HAVE DRIED
OUT EARLY NEXT WEEK. CONFIDENCE IS SHAKY BUT HOPE IT STAYS THAT WAY.
KAM

&&

.HYDROLOGY...A WARM FRONT HELD HEAVIER RAINFALL NORTH OF THE
WA/BRITISH COLUMBIA BORDER TODAY. THIS IS ALLOWING MOST RIVERS TO
SLOWLY RECEDE ACROSS WRN WA. RAIN AMOUNTS UP TO 5 INCHES SINCE
MONDAY IN PLACES LIKE MOUNT RAINIER AND THE
SKYKOMISH-SNOQUALMIE-TOLT-SNOHOMISH BASIN WILL STILL CAUSE SOME
RESIDUAL FLOODING...MAINLY THROUGH THIS EVENING.

ANOTHER FRONT WILL BRING RENEWED RAINFALL TO WRN WA TONIGHT AND
THURSDAY...LOCALLY HEAVY IN THE MOUNTAINS. THE OLYMPICS AND NORTH
CASCADES WILL RECEIVE THE HEAVIEST RAINFALL WITH 2 TO 4 INCHES OF
RAIN EXPECTED. 1 TO 2 INCHES MAY FALL IN THE CENTRAL CASCADES. THE
SNOW LEVEL WILL BE NEAR 7000 FEET.

A SECONDARY SURGE OF MOISTURE WILL ARRIVE THURSDAY NIGHT INTO
FRIDAY. MODELS VARY MUCH MORE ON THE DISTRIBUTION AND POTENTIAL
RAINFALL AMOUNTS WITH THIS SECOND FRONTAL SYSTEM. IN
GENERAL...HEAVIER RAIN AMOUNTS THURSDAY NIGHT AND FRIDAY SHOULD
OCCUR ALONG S/SW FACING SLOPES OF THE OLYMPICS AND N
CASCADES...ALTHOUGH THE CENTRAL CASCADES COULD ALSO SEE HEAVY
PRECIPITATION BY FRIDAY. ADDITIONAL AMOUNTS OF 2 TO 3 INCHES ARE
POSSIBLE. THIS MEANS THE 36-48 HOUR RAINFALL TOTALS FOR THE OLYMPICS
AND CASCADES MAY REACH 4 TO 7 INCHES WITH LOCALLY HIGHER
AMOUNTS...ESPECIALLY IN THE N CASCADES.

THESE AMOUNTS WILL LIKELY DRIVE SEVERAL RIVERS TO FLOOD...ALTHOUGH
WIDESPREAD MAJOR FLOODING APPEARS UNLIKELY. AT HIGHEST RISK FOR
FLOODING IS THE SKOKOMISH RIVER IN THE OLYMPICS...THE NOOKSACK AND
SKAGIT RIVERS IN THE NORTH...AND THE
STILLAGUAMISH...SNOQUALMIE...AND TOLT ACROSS CENTRAL AREAS. IF THE
HEAVIER RAIN SHIFTS FAR ENOUGH SOUTH THEN FLOODING COULD BE POSSIBLE
ON THE DESCHUTES RIVER AND THE REACH OF THE SKOOKUMCHUCK RIVER NEAR
BUCODA IN THURSTON COUNTY.

A FLOOD WATCH REMAINS IN EFFECT THROUGH FRIDAY...WHICH INCLUDES ALL
THE COUNTIES WITH RIVERS FLOWING OFF THE WEST SLOPES OF THE CASCADES
AND MASON COUNTY FOR THE POSSIBILITY OF A FLOOD ON THE SKOKOMISH.

COLDER AND DRIER WEATHER IS LIKELY THIS WEEKEND...SO RIVERS SHOULD
RECEDE AND THE FLOOD THREAT WILL END FOR THE FORESEEABLE FUTURE.

MERCER

&&

.AVIATION...THE FLOW ALOFT IS STRONG AND FROM THE WEST SOUTHWEST.
THE AIR MASS IS RATHER MOIST AND RELATIVELY STABLE AFTER THE PASSAGE
OF A WARM FRONT. CIGS ARE CURRENTLY MVFR TO VFR ACROSS THE AREA. A
COLD FRONT IS TIMED TO MOVE THROUGH THE AREA OVERNIGHT TONIGHT AND
DESTABILIZE THINGS...CIGS MAY RISE A BIT BEFORE THE FRONT PASSES
THROUGH...BUT THEN CIGS WILL DETERIORATE AFTERWARDS TO IFR OR MVFR.
SLY SURFACE WINDS WILL BE STRONG AND GUSTY WITH THE FRONT AND INTO
THE DAY THURSDAY.

KSEA...SOUTH WIND INCREASING TO 12 TO 14 KT OVERNIGHT WITH GUSTS TO
20 KT DURING AND AFTER FRONTAL PASSAGE AROUND 7 TO 9Z. CIGS WILL
CHANGE FROM VFR TO MVFR SHORTLY AFTER THE FRONTAL PASSAGE AS A LOWER
DECK OF CLOUDS MOVES IN. JSMITH

&&

.MARINE...A COLD FRONT WILL MOVE ONSHORE TONIGHT. GALE WARNINGS HAVE
BEEN ISSUED TONIGHT FOR THE COAST...ENTRANCES TO THE STRAIT...AND
NORTHERN INLAND WATERS AS THEY ARE MOST PRONE TO STRONG SOUTHERLY
WINDS THAT THE FRONT WILL BRING. MODERATE TO STRONG ONSHORE AND
SOUTHERLY FLOW WILL PREVAIL BEHIND THE FRONT ON THURSDAY...AND SMALL
CRAFT ADVISORIES HAVE BEEN ISSUED FOR MOST OF THE WATERS THROUGH
THURSDAY NIGHT.

ANOTHER COLD FRONT WILL MOVE THROUGH THE WATERS EARLY FRIDAY. THIS
FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND MODERATE NORTHERLY WINDS OVER THE OTHER WATERS
LATER FRIDAY INTO SATURDAY. MODERATE OFFSHORE FLOW IS LIKELY SUNDAY
INTO MONDAY WITH HIGHER SEA LEVEL PRESSURE INLAND AND LOWER PRESSURE
OVER THE SOUTHERN COASTAL WATERS. JSMITH

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES AND WARNINGS ARE IN EFFECT FOR PORTIONS OF
      WESTERN WASHINGTON.
     WIND ADVISORY N COAST AND PARTS OF N INTERIOR TONIGHT.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
    .SMALL CRAFT ADVISORY GRAYS HARBOR BAR FOR ROUGH BAR.
    .GALE WARNING COASTAL WATERS...ENTRANCES STRAIT OF JUAN DE
     FUCA...AND NORTHERN INLAND WATERS.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML














000
FXUS66 KSEW 261832 AAA
AFDSEW

AREA FORECAST DISCUSSION...UPDATED ADDED AVN MAR SECTIONS
NATIONAL WEATHER SERVICE SEATTLE WA
1032 AM PST WED NOV 26 2014

.SYNOPSIS...A WARM FRONT WILL REMAIN NEAR THE CANADIAN BORDER TODAY.
A COLD FRONT WILL MOVE EAST ACROSS THE AREA TONIGHT FOR MORE RAIN
AND WINDY CONDITIONS. RAIN WILL CONTINUE ON THANKSGIVING DAY AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH THEN CROSSES THE AREA
ON FRIDAY. A COLD UPPER LEVEL TROUGH WILL BE OVER THE AREA FRIDAY
NIGHT AND SATURDAY FOR A CHANCE OF SHOWERS...POSSIBLY MIXED WITH
SNOW. COOL DRY AND BREEZY WEATHER WILL DEVELOP SATURDAY NIGHT AND
SUNDAY AS HIGH PRESSURE BUILDS OVER BRITISH COLUMBIA.

&&

.SHORT TERM...WESTERN WASHINGTON IS IN THE WARM SECTOR OF A WARM
FRONT THAT IS NEARLY STATIONARY OVER SOUTHERN B.C. THIS MORNING.
TEMPERATURES WERE RATHER MILD OVERNIGHT FROM THE GREATER PUGET SOUND
REGION SOUTHWARD...AND REMAIN SO THIS MORNING WITH READINGS IN THE
MID TO UPPER 50S. THE WARM AIR HAS NOT QUITE REACHED THE NW INTERIOR
WHERE TEMPS WERE STILL IN THE UPPER 40S...BUT SHOULD GET THERE
EVENTUALLY TODAY. THE LULL IN RAIN WILL CONTINUE UNTIL THE NEXT
FRONT ARRIVES TONIGHT.

THE APPROACHING FRONT WAS OFFSHORE NEARING 130W AT 16Z/8 AM THIS
MORNING AND IS EXPECTED TO CROSS THE COAST AROUND 06Z/10 PM TONIGHT.
FROPA OVER THE INTERIOR SHOULD BE BEFORE 12Z/4 AM. S-SE SURFACE
WINDS WILL INCREASE AHEAD OF THE FRONT LATE THIS AFTERNOON AND
EVENING. STRONGEST WINDS SHOULD PEAK THIS EVENING IN THE LOW END
WIND ADVISORY RANGE FOR THE USUAL AREAS...COAST AND N INTERIOR.
WINDS WILL DIMINISH AFTER MIDNIGHT AS THE FRONT MOVES INLAND.

IN ADDITION...STRONG SW LOW LEVEL FLOW ALOFT AT 850 MB IS EXPECTED
TO DEVELOP AS THE FRONT APPROACHES THIS EVENING THEN CONTINUE IN THE
35-45KT RANGE THROUGH THURSDAY NIGHT AS A COLD FRONT OVER B.C. MOVES
S. THE SW FLOW WILL IMPACT MAINLY THE OLYMPICS AND N CASCADES WITH
HEAVY RAIN...WITH WIDESPREAD 3 INCH AMOUNTS AND A BULLSEYE OF AROUND
5 INCHES AROUND MT BAKER FOR THE 36 HOUR PERIOD 00Z THURSDAY THROUGH
12Z FRIDAY. SNOW LEVELS WILL REMAIN HIGH...6000 TO 7000 FEET TONIGHT
LOWERING TO 5000-6000 FEET THURSDAY NIGHT. THE HEAVY RAIN HAS A GOOD
CHANCE OF PRODUCING SOME FLOODING ON SOME OF THE RIVERS FLOWING OFF
THE N CASCADES. A FLOOD WATCH REMAINS IN EFFECT...SEE THE HYDRO
SECTION BELOW FOR MORE DETAILS.

AFTER TONIGHTS FRONT EXITS THE AREA EARLY THURSDAY MORNING...THE OLD
WARM FRONT OVER SOUTHERN B.C. WILL BE DRIVEN SOUTH ACROSS W WA AS A
COLD FRONT...BY A STRONG UPPER LEVEL TROUGH DIVING SOUTH FROM
NORTHERN B.C.  MODELS BRING THE BACK EDGE OF THE FRONT TO THE N
INTERIOR FRIDAY MORNING...THEN DOWN ACROSS PUGET SOUND LATE FRIDAY
AFTERNOON...THEN FINALLY APPROACHING THE OREGON BORDER LATE FRIDAY
EVENING. RAIN WILL CONTINUE WITH THE FRONT AS IT MOVES S.

INTERESTING WEATHER WILL CONTINUE FRIDAY NIGHT. THE LOW LEVEL AIR
MASS WILL REMAIN MOIST. THE APPROACHING UPPER LEVEL TROUGH IS VERY
COLD ALOFT AND WILL GRADUALLY COOL THE AIR MASS ENOUGH OVERNIGHT SO
THAT RAIN AND SNOW MIXED OR JUST SNOW IS POSSIBLE BY LATE FRIDAY
NIGHT INTO SATURDAY MORNING. THE UPPER LEVEL TROUGH WILL PROVIDE
SOME LOW LEVEL INSTABILITY AND LIFT TO SUPPORT SHOWER ACTIVITY. IN
ADDITION WINDS WILL BE RIGHT FOR A CONVERGENCE ZONE TO FORM OVER
CENTRAL PUGET SOUND.

A STRONG SURFACE HIGH FORMING OVER THE B.C.INTERIOR WILL GENERATE
FRASER RIVER VALLEY OUTFLOW WINDS ON SATURDAY. THIS WILL SPREAD COOL
DRY LOW LEVEL AIR SOUTHWARD ACROSS W WA...WITH CLEARING FROM THE
NORTH SATURDAY AFTERNOON AND EVENING. THE NE WINDS COULD BE STRONG
ENOUGH TO REACH WIND ADVISORY CRITERIA OVER THE FAR N INTERIOR. THE
COLD AIR WILL LEAD TO LOWS IN THE 20S ACROSS W WA SUNDAY MORNING. KAM

.LONG TERM...PREVIOUS DISCUSSION FROM THE 330 AM AFD...LONG RANGE
MODELS SHOW A COOL AND DRY AIR MASS OVER WESTERN WA ON SUNDAY. HIGH
PRES OVER INTERIOR B.C. WILL MAINTAIN EASTERLY FLOW THROUGH THE
PASSES. LOWS SUNDAY MORNING WILL BE DOWN TO THE 20S TO LOWER 30S
ONCE AGAIN. HIGHS ARE ALSO BELOW NORMAL ON SUNDAY WITH UPPER 30S TO
LOWER 40S EXPECTED. MODELS WERE SHOWING SOME MOISTURE SPREADING
NORTH SUN NIGHT OR MON BUT THEY ARE NOW BACKING OFF ON THIS IDEA. SO
THE FORECAST IS NOW LOOKING DRIER OVER THIS PERIOD AS WELL. THE
FORECAST IS ALSO LOOKING DRIER THROUGH MIDWEEK NOW AS THE EURO TRIES
TO BUILD A RIDGE OVER THE PAC NW. 33

&&

.HYDROLOGY...A WARM FRONT LIFTED NORTH INTO SOUTHERN BRITISH
COLUMBIA THIS MORNING WHERE THE HEAVIER RAIN NOW RESIDES. THE
COASTAL RADAR IS PICKING UP SOME STEADY LIGHT RAIN CONCENTRATED
ALONG THE COAST AND W/SW SLOPES OF THE OLYMPICS. UP TO A COUPLE
TENTHS HAS FALLEN THE PAST 3 HOURS OVER THE OLYMPICS WITH THE
RAINFALL RATES CONTINUING A DOWNTREND. RAIN IS ALSO DECREASING
ACROSS THE N CASCADES WHERE UP TO 1 INCH FELL OVERNIGHT. RAIN IS NOW
IN A LULL ACROSS WRN WA AND ANY ADDITIONAL RAIN AMOUNTS SHOULD BE
LESS THAN A HALF INCH AND MOSTLY CONFINED TO THE CASCADES OF
WHATCOM/SKAGIT COUNTIES AND THE OLYMPICS. BECAUSE RAINFALL HAS
TAPERED...THE ODDS OF THE NOOKSACK AT CEDARVILLE REACHING FLOOD
TODAY ARE LOW BUT STILL NEEDS TO BE WATCHED. THE STILLAGUAMISH
REACHED FLOOD OVERNIGHT BUT IS ON THE DOWNTURN AND SHOULD FALL BELOW
FLOOD LATER TODAY.

THE SNOQUALMIE RIVER AT THE FALLS CRESTED EARLY THIS MORNING WITH
THE CREST MOVING DOWNSTREAM THROUGH CARNATION LATE THIS AFTERNOON.
FLOODING ON THE SNOQUALMIE WILL CONTINUE THROUGH TONIGHT. THE
SKYKOMISH RIVER RAN WITHIN A FOOT OF FLOOD STAGE EARLIER THIS
MORNING BUT IS NOW ON THE DOWNTURN. THE SNOHOMISH...WHICH IS FORMED
BY THE CONFLUENCE OF THE SKYKOMISH AND SNOQUALMIE RIVERS...COULD
HAVE SOME FLOODING LATER TODAY.

THE RIVERS THAT FLOW OFF MOUNT RAINIER ARE RECEDING. THE FLOODING
HAS ENDED FOR THE CARBON AND NISQUALLY RIVERS...BUT FLOODING WILL
CONTINUE FOR THE COWLITZ AND REACH OF THE PUYALLUP NEAR ORTING.

ANOTHER FRONT WILL BRING RENEWED RAINFALL TO WRN WA TONIGHT AND
THURSDAY...LOCALLY HEAVY IN THE MOUNTAINS. THE OLYMPICS AND NORTH
CASCADES WILL RECEIVE THE HEAVIEST RAINFALL...BUT LOCALLY UP TO 5
INCHES OVER MOUNT RAINIER AND SKYKOMISH-SNOQUALMIE-TOLT-SNOHOMISH
BASIN IS POSSIBLE TOO. THE SNOW LEVEL WILL BE 5500 TO 7000 FT FOR
MOST OF THE EVENT...THEN FALL ON FRIDAY AS A COLD FRONT MOVES
THROUGH FROM THE NORTHWEST AND PRECIPITATION DECREASES.

A MAJOR FLOODING EPISODE IS UNLIKELY...BUT THE RAINFALL COULD
CERTAINLY RENEW FLOODING ON THE RIVERS THAT FLOODED OR ALMOST
FLOODED AND SOME OTHER RIVERS COULD REACH FLOOD STAGE AS WELL. A
FLOOD WATCH REMAINS IN EFFECT THROUGH FRIDAY...WHICH INCLUDES ALL
THE COUNTIES WITH RIVERS FLOWING OFF THE WEST SLOPES OF THE CASCADES
AND MASON COUNTY FOR THE POSSIBILITY OF A FLOOD ON THE SKOKOMISH.

COLDER AND DRIER WEATHER IS LIKELY THIS WEEKEND...SO RIVERS SHOULD
RECEDE AND THE FLOOD THREAT WILL END FOR THE FORESEEABLE FUTURE.

MERCER

&&

.AVIATION...THE FLOW ALOFT IS STRONG AND FROM THE WEST. THE AIR MASS
IS RATHER MOIST AFTER THE PASSAGE OF A WARM FRONT. CIGS ARE MVFR TO
VFR ACROSS THE AREA TODAY AS THE LAST OF THE SHOWERS MOVE OUT. A
COLD FRONT IS TIMED TO MOVE THROUGH THE AREA OVERNIGHT
TONIGHT...CIGS WILL BE HIGHER JUST BEFORE FRONTAL PASSAGE AND THEN
FALL JUST AFTER FRONTAL PASSAGE TO LOW MVFR IN MOST AREAS. SLY
SURFACE WINDS WILL BE STRONG AND GUSTY WITH THE FRONT AND INTO THE
MORNING.

KSEA...SOUTH WIND INCREASING FROM 10 TO 12 KT TODAY TO 12 TO 14 KT
OVERNIGHT WITH GUSTS TO 20 KT DURING AND AFTER FRONTAL PASSAGE
AROUND 7 OR 8Z. CONDITIONS WILL DETERIORATE LATE TONIGHT AS THE NEXT
FRONTAL SYSTEM ARRIVES. JSMITH

&&

.MARINE...A COLD FRONT WILL APPROACH THE WATERS TODAY AND MOVE
ONSHORE TONIGHT. SMALL CRAFT ADVISORY SOUTHERLY WINDS WILL BE
COMMON IN MOST WATERS TODAY...THEN GALES FOR SOME WATERS TONIGHT AS
THE FRONT MOVES THROUGH. MODERATE TO STRONG ONSHORE FLOW WILL
PREVAIL BEHIND THE FRONT ON THURSDAY.

ANOTHER COLD FRONT WILL MOVE THROUGH THE WATERS EARLY FRIDAY. THIS
FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND MODERATE NORTHERLY WINDS OVER THE OTHER WATERS
LATER FRIDAY INTO SATURDAY. JSMITH

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES AND WARNINGS IN EFFECT FOR PORTIONS OF
     WESTERN WASHINGTON.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
    .SMALL CRAFT ADVISORY GRAYS HARBOR BAR FOR ROUGH BAR.
    .GALE WARNING COASTAL WATERS...ENTRANCES STRAIT OF JUAN DE
     FUCA...AND NORTHERN INLAND WATERS LATE THIS AFTERNOON AND
     TONIGHT.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML











000
FXUS66 KSEW 261753
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
952 AM PST WED NOV 26 2014

.SYNOPSIS...A WARM FRONT WILL REMAIN NEAR THE CANADIAN BORDER TODAY.
A COLD FRONT WILL MOVE EAST ACROSS THE AREA TONIGHT FOR MORE RAIN
AND WINDY CONDITIONS. RAIN WILL CONTINUE ON THANKSGIVING DAY AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH THEN CROSSES THE AREA
ON FRIDAY. A COLD UPPER LEVEL TROUGH WILL BE OVER THE AREA FRIDAY
NIGHT AND SATURDAY FOR A CHANCE OF SHOWERS...POSSIBLY MIXED WITH
SNOW. COOL DRY AND BREEZY WEATHER WILL DEVELOP SATURDAY NIGHT AND
SUNDAY AS HIGH PRESSURE BUILDS OVER BRITISH COLUMBIA.

&&

.SHORT TERM...WESTERN WASHINGTON IS IN THE WARM SECTOR OF A WARM
FRONT THAT IS NEARLY STATIONARY OVER SOUTHERN B.C. THIS MORNING.
TEMPERATURES WERE RATHER MILD OVERNIGHT FROM THE GREATER PUGET SOUND
REGION SOUTHWARD...AND REMAIN SO THIS MORNING WITH READINGS IN THE
MID TO UPPER 50S. THE WARM AIR HAS NOT QUITE REACHED THE NW INTERIOR
WHERE TEMPS WERE STILL IN THE UPPER 40S...BUT SHOULD GET THERE
EVENTUALLY TODAY. THE LULL IN RAIN WILL CONTINUE UNTIL THE NEXT
FRONT ARRIVES TONIGHT.

THE APPROACHING FRONT WAS OFFSHORE NEARING 130W AT 16Z/8 AM THIS
MORNING AND IS EXPECTED TO CROSS THE COAST AROUND 06Z/10 PM TONIGHT.
FROPA OVER THE INTERIOR SHOULD BE BEFORE 12Z/4 AM. S-SE SURFACE
WINDS WILL INCREASE AHEAD OF THE FRONT LATE THIS AFTERNOON AND
EVENING. STRONGEST WINDS SHOULD PEAK THIS EVENING IN THE LOW END
WIND ADVISORY RANGE FOR THE USUAL AREAS...COAST AND N INTERIOR.
WINDS WILL DIMINISH AFTER MIDNIGHT AS THE FRONT MOVES INLAND.

IN ADDITION...STRONG SW LOW LEVEL FLOW ALOFT AT 850 MB IS EXPECTED
TO DEVELOP AS THE FRONT APPROACHES THIS EVENING THEN CONTINUE IN THE
35-45KT RANGE THROUGH THURSDAY NIGHT AS A COLD FRONT OVER B.C. MOVES
S. THE SW FLOW WILL IMPACT MAINLY THE OLYMPICS AND N CASCADES WITH
HEAVY RAIN...WITH WIDESPREAD 3 INCH AMOUNTS AND A BULLSEYE OF AROUND
5 INCHES AROUND MT BAKER FOR THE 36 HOUR PERIOD 00Z THURSDAY THROUGH
12Z FRIDAY. SNOW LEVELS WILL REMAIN HIGH...6000 TO 7000 FEET TONIGHT
LOWERING TO 5000-6000 FEET THURSDAY NIGHT. THE HEAVY RAIN HAS A GOOD
CHANCE OF PRODUCING SOME FLOODING ON SOME OF THE RIVERS FLOWING OFF
THE N CASCADES. A FLOOD WATCH REMAINS IN EFFECT...SEE THE HYDRO
SECTION BELOW FOR MORE DETAILS.

AFTER TONIGHTS FRONT EXITS THE AREA EARLY THURSDAY MORNING...THE OLD
WARM FRONT OVER SOUTHERN B.C. WILL BE DRIVEN SOUTH ACROSS W WA AS A
COLD FRONT...BY A STRONG UPPER LEVEL TROUGH DIVING SOUTH FROM
NORTHERN B.C.  MODELS BRING THE BACK EDGE OF THE FRONT TO THE N
INTERIOR FRIDAY MORNING...THEN DOWN ACROSS PUGET SOUND LATE FRIDAY
AFTERNOON...THEN FINALLY APPROACHING THE OREGON BORDER LATE FRIDAY
EVENING. RAIN WILL CONTINUE WITH THE FRONT AS IT MOVES S.

INTERESTING WEATHER WILL CONTINUE FRIDAY NIGHT. THE LOW LEVEL AIR
MASS WILL REMAIN MOIST. THE APPROACHING UPPER LEVEL TROUGH IS VERY
COLD ALOFT AND WILL GRADUALLY COOL THE AIR MASS ENOUGH OVERNIGHT SO
THAT RAIN AND SNOW MIXED OR JUST SNOW IS POSSIBLE BY LATE FRIDAY
NIGHT INTO SATURDAY MORNING. THE UPPER LEVEL TROUGH WILL PROVIDE
SOME LOW LEVEL INSTABILITY AND LIFT TO SUPPORT SHOWER ACTIVITY. IN
ADDITION WINDS WILL BE RIGHT FOR A CONVERGENCE ZONE TO FORM OVER
CENTRAL PUGET SOUND.

A STRONG SURFACE HIGH FORMING OVER THE B.C.INTERIOR WILL GENERATE
FRASER RIVER VALLEY OUTFLOW WINDS ON SATURDAY. THIS WILL SPREAD COOL
DRY LOW LEVEL AIR SOUTHWARD ACROSS W WA...WITH CLEARING FROM THE
NORTH SATURDAY AFTERNOON AND EVENING. THE NE WINDS COULD BE STRONG
ENOUGH TO REACH WIND ADVISORY CRITERIA OVER THE FAR N INTERIOR. THE
COLD AIR WILL LEAD TO LOWS IN THE 20S ACROSS W WA SUNDAY MORNING. KAM

.LONG TERM...PREVIOUS DISCUSSION FROM THE 330 AM AFD...LONG RANGE
MODELS SHOW A COOL AND DRY AIR MASS OVER WESTERN WA ON SUNDAY. HIGH
PRES OVER INTERIOR B.C. WILL MAINTAIN EASTERLY FLOW THROUGH THE
PASSES. LOWS SUNDAY MORNING WILL BE DOWN TO THE 20S TO LOWER 30S
ONCE AGAIN. HIGHS ARE ALSO BELOW NORMAL ON SUNDAY WITH UPPER 30S TO
LOWER 40S EXPECTED. MODELS WERE SHOWING SOME MOISTURE SPREADING
NORTH SUN NIGHT OR MON BUT THEY ARE NOW BACKING OFF ON THIS IDEA. SO
THE FORECAST IS NOW LOOKING DRIER OVER THIS PERIOD AS WELL. THE
FORECAST IS ALSO LOOKING DRIER THROUGH MIDWEEK NOW AS THE EURO TRIES
TO BUILD A RIDGE OVER THE PAC NW. 33

&&

.HYDROLOGY...A WARM FRONT LIFTED NORTH INTO SOUTHERN BRITISH
COLUMBIA THIS MORNING WHERE THE HEAVIER RAIN NOW RESIDES. THE
COASTAL RADAR IS PICKING UP SOME STEADY LIGHT RAIN CONCENTRATED
ALONG THE COAST AND W/SW SLOPES OF THE OLYMPICS. UP TO A COUPLE
TENTHS HAS FALLEN THE PAST 3 HOURS OVER THE OLYMPICS WITH THE
RAINFALL RATES CONTINUING A DOWNTREND. RAIN IS ALSO DECREASING
ACROSS THE N CASCADES WHERE UP TO 1 INCH FELL OVERNIGHT. RAIN IS NOW
IN A LULL ACROSS WRN WA AND ANY ADDITIONAL RAIN AMOUNTS SHOULD BE
LESS THAN A HALF INCH AND MOSTLY CONFINED TO THE CASCADES OF
WHATCOM/SKAGIT COUNTIES AND THE OLYMPICS. BECAUSE RAINFALL HAS
TAPERED...THE ODDS OF THE NOOKSACK AT CEDARVILLE REACHING FLOOD
TODAY ARE LOW BUT STILL NEEDS TO BE WATCHED. THE STILLAGUAMISH
REACHED FLOOD OVERNIGHT BUT IS ON THE DOWNTURN AND SHOULD FALL BELOW
FLOOD LATER TODAY.

THE SNOQUALMIE RIVER AT THE FALLS CRESTED EARLY THIS MORNING WITH
THE CREST MOVING DOWNSTREAM THROUGH CARNATION LATE THIS AFTERNOON.
FLOODING ON THE SNOQUALMIE WILL CONTINUE THROUGH TONIGHT. THE
SKYKOMISH RIVER RAN WITHIN A FOOT OF FLOOD STAGE EARLIER THIS
MORNING BUT IS NOW ON THE DOWNTURN. THE SNOHOMISH...WHICH IS FORMED
BY THE CONFLUENCE OF THE SKYKOMISH AND SNOQUALMIE RIVERS...COULD
HAVE SOME FLOODING LATER TODAY.

THE RIVERS THAT FLOW OFF MOUNT RAINIER ARE RECEDING. THE FLOODING
HAS ENDED FOR THE CARBON AND NISQUALLY RIVERS...BUT FLOODING WILL
CONTINUE FOR THE COWLITZ AND REACH OF THE PUYALLUP NEAR ORTING.

ANOTHER FRONT WILL BRING RENEWED RAINFALL TO WRN WA TONIGHT AND
THURSDAY...LOCALLY HEAVY IN THE MOUNTAINS. THE OLYMPICS AND NORTH
CASCADES WILL RECEIVE THE HEAVIEST RAINFALL...BUT LOCALLY UP TO 5
INCHES OVER MOUNT RAINIER AND SKYKOMISH-SNOQUALMIE-TOLT-SNOHOMISH
BASIN IS POSSIBLE TOO. THE SNOW LEVEL WILL BE 5500 TO 7000 FT FOR
MOST OF THE EVENT...THEN FALL ON FRIDAY AS A COLD FRONT MOVES
THROUGH FROM THE NORTHWEST AND PRECIPITATION DECREASES.

A MAJOR FLOODING EPISODE IS UNLIKELY...BUT THE RAINFALL COULD
CERTAINLY RENEW FLOODING ON THE RIVERS THAT FLOODED OR ALMOST
FLOODED AND SOME OTHER RIVERS COULD REACH FLOOD STAGE AS WELL. A
FLOOD WATCH REMAINS IN EFFECT THROUGH FRIDAY...WHICH INCLUDES ALL
THE COUNTIES WITH RIVERS FLOWING OFF THE WEST SLOPES OF THE CASCADES
AND MASON COUNTY FOR THE POSSIBILITY OF A FLOOD ON THE SKOKOMISH.

COLDER AND DRIER WEATHER IS LIKELY THIS WEEKEND...SO RIVERS SHOULD
RECEDE AND THE FLOOD THREAT WILL END FOR THE FORESEEABLE FUTURE.

MERCER

&&

.AVIATION...DELAYED...THE WARM FRONT THAT BROUGHT ALL THE RAIN TO
WESTERN WASHINGTON THE PAST COUPLE DAYS HAS MOVED INTO BRITISH
COLUMBIA. HOWEVER A WARM MOIST AIR MASS REMAINS OVER WESTERN
WASHINGTON WITH WIDESPREAD LOW-END MVFR TO IFR
CONDITIONS...INCLUDING SOME VISIBILITIES BELOW 3SM IN FOG AND LIGHT
PRECIPITATION.

IMPROVEMENT TODAY WILL BE GRADUAL AND MAINLY LIMITED TO THE PUGET
SOUND REGION AND SOUTHWEST INTERIOR. ANOTHER VIGOROUS FRONTAL SYSTEM
WILL BRING MORE RAIN TO THE COAST LATE TODAY...SPREADING INTO THE
WESTERN WASHINGTON INTERIOR THIS EVENING. WHATEVER IMPROVEMENT
OCCURS TODAY IS LIKELY TO BE QUICKLY UNDONE AS A RESULT.

KSEA...SOUTH WIND MOSTLY 10-16 KT GUSTING 24 KT THROUGH TONIGHT...
EXCEPT THERE COULD BE A BRIEF LULL LATE THIS MORNING AND AFTERNOON.
THE GRADUAL IMPROVEMENT IN CEILINGS SHOULD CONTINUE TODAY...BUT
CONDITIONS WILL DETERIORATE TONIGHT AS THE NEXT FRONTAL SYSTEM
ARRIVES.   MCDONNAL

&&

.MARINE...DELAYED...A COLD FRONT WILL APPROACH THE WATERS TODAY AND
MOVE ONSHORE TONIGHT. SMALL CRAFT ADVISORY SOUTHERLY WINDS WILL BE
COMMON MOST WATERS TODAY...THEN GALES FOR SOME WATERS TONIGHT AS THE
FRONT MOVES THROUGH. MODERATE TO STRONG ONSHORE FLOW WILL PREVAIL
BEHIND THE FRONT ON THURSDAY.

ANOTHER COLD FRONT WILL MOVE THROUGH THE WATERS ON FRIDAY. THIS
FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND MODERATE NORTHERLY WINDS OVER THE OTHER WATERS
LATER FRIDAY INTO SATURDAY. SCHNEIDER

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES AND WARNINGS IN EFFECT FOR PORTIONS OF
     WESTERN WASHINGTON.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
    .SMALL CRAFT ADVISORY GRAYS HARBOR BAR FOR ROUGH BAR.
    .GALE WARNING COASTAL WATERS...ENTRANCES STRAIT OF JUAN DE
     FUCA...AND NORTHERN INLAND WATERS LATE THIS AFTERNOON AND
     TONIGHT.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML









000
FXUS66 KSEW 261753
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
952 AM PST WED NOV 26 2014

.SYNOPSIS...A WARM FRONT WILL REMAIN NEAR THE CANADIAN BORDER TODAY.
A COLD FRONT WILL MOVE EAST ACROSS THE AREA TONIGHT FOR MORE RAIN
AND WINDY CONDITIONS. RAIN WILL CONTINUE ON THANKSGIVING DAY AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH THEN CROSSES THE AREA
ON FRIDAY. A COLD UPPER LEVEL TROUGH WILL BE OVER THE AREA FRIDAY
NIGHT AND SATURDAY FOR A CHANCE OF SHOWERS...POSSIBLY MIXED WITH
SNOW. COOL DRY AND BREEZY WEATHER WILL DEVELOP SATURDAY NIGHT AND
SUNDAY AS HIGH PRESSURE BUILDS OVER BRITISH COLUMBIA.

&&

.SHORT TERM...WESTERN WASHINGTON IS IN THE WARM SECTOR OF A WARM
FRONT THAT IS NEARLY STATIONARY OVER SOUTHERN B.C. THIS MORNING.
TEMPERATURES WERE RATHER MILD OVERNIGHT FROM THE GREATER PUGET SOUND
REGION SOUTHWARD...AND REMAIN SO THIS MORNING WITH READINGS IN THE
MID TO UPPER 50S. THE WARM AIR HAS NOT QUITE REACHED THE NW INTERIOR
WHERE TEMPS WERE STILL IN THE UPPER 40S...BUT SHOULD GET THERE
EVENTUALLY TODAY. THE LULL IN RAIN WILL CONTINUE UNTIL THE NEXT
FRONT ARRIVES TONIGHT.

THE APPROACHING FRONT WAS OFFSHORE NEARING 130W AT 16Z/8 AM THIS
MORNING AND IS EXPECTED TO CROSS THE COAST AROUND 06Z/10 PM TONIGHT.
FROPA OVER THE INTERIOR SHOULD BE BEFORE 12Z/4 AM. S-SE SURFACE
WINDS WILL INCREASE AHEAD OF THE FRONT LATE THIS AFTERNOON AND
EVENING. STRONGEST WINDS SHOULD PEAK THIS EVENING IN THE LOW END
WIND ADVISORY RANGE FOR THE USUAL AREAS...COAST AND N INTERIOR.
WINDS WILL DIMINISH AFTER MIDNIGHT AS THE FRONT MOVES INLAND.

IN ADDITION...STRONG SW LOW LEVEL FLOW ALOFT AT 850 MB IS EXPECTED
TO DEVELOP AS THE FRONT APPROACHES THIS EVENING THEN CONTINUE IN THE
35-45KT RANGE THROUGH THURSDAY NIGHT AS A COLD FRONT OVER B.C. MOVES
S. THE SW FLOW WILL IMPACT MAINLY THE OLYMPICS AND N CASCADES WITH
HEAVY RAIN...WITH WIDESPREAD 3 INCH AMOUNTS AND A BULLSEYE OF AROUND
5 INCHES AROUND MT BAKER FOR THE 36 HOUR PERIOD 00Z THURSDAY THROUGH
12Z FRIDAY. SNOW LEVELS WILL REMAIN HIGH...6000 TO 7000 FEET TONIGHT
LOWERING TO 5000-6000 FEET THURSDAY NIGHT. THE HEAVY RAIN HAS A GOOD
CHANCE OF PRODUCING SOME FLOODING ON SOME OF THE RIVERS FLOWING OFF
THE N CASCADES. A FLOOD WATCH REMAINS IN EFFECT...SEE THE HYDRO
SECTION BELOW FOR MORE DETAILS.

AFTER TONIGHTS FRONT EXITS THE AREA EARLY THURSDAY MORNING...THE OLD
WARM FRONT OVER SOUTHERN B.C. WILL BE DRIVEN SOUTH ACROSS W WA AS A
COLD FRONT...BY A STRONG UPPER LEVEL TROUGH DIVING SOUTH FROM
NORTHERN B.C.  MODELS BRING THE BACK EDGE OF THE FRONT TO THE N
INTERIOR FRIDAY MORNING...THEN DOWN ACROSS PUGET SOUND LATE FRIDAY
AFTERNOON...THEN FINALLY APPROACHING THE OREGON BORDER LATE FRIDAY
EVENING. RAIN WILL CONTINUE WITH THE FRONT AS IT MOVES S.

INTERESTING WEATHER WILL CONTINUE FRIDAY NIGHT. THE LOW LEVEL AIR
MASS WILL REMAIN MOIST. THE APPROACHING UPPER LEVEL TROUGH IS VERY
COLD ALOFT AND WILL GRADUALLY COOL THE AIR MASS ENOUGH OVERNIGHT SO
THAT RAIN AND SNOW MIXED OR JUST SNOW IS POSSIBLE BY LATE FRIDAY
NIGHT INTO SATURDAY MORNING. THE UPPER LEVEL TROUGH WILL PROVIDE
SOME LOW LEVEL INSTABILITY AND LIFT TO SUPPORT SHOWER ACTIVITY. IN
ADDITION WINDS WILL BE RIGHT FOR A CONVERGENCE ZONE TO FORM OVER
CENTRAL PUGET SOUND.

A STRONG SURFACE HIGH FORMING OVER THE B.C.INTERIOR WILL GENERATE
FRASER RIVER VALLEY OUTFLOW WINDS ON SATURDAY. THIS WILL SPREAD COOL
DRY LOW LEVEL AIR SOUTHWARD ACROSS W WA...WITH CLEARING FROM THE
NORTH SATURDAY AFTERNOON AND EVENING. THE NE WINDS COULD BE STRONG
ENOUGH TO REACH WIND ADVISORY CRITERIA OVER THE FAR N INTERIOR. THE
COLD AIR WILL LEAD TO LOWS IN THE 20S ACROSS W WA SUNDAY MORNING. KAM

.LONG TERM...PREVIOUS DISCUSSION FROM THE 330 AM AFD...LONG RANGE
MODELS SHOW A COOL AND DRY AIR MASS OVER WESTERN WA ON SUNDAY. HIGH
PRES OVER INTERIOR B.C. WILL MAINTAIN EASTERLY FLOW THROUGH THE
PASSES. LOWS SUNDAY MORNING WILL BE DOWN TO THE 20S TO LOWER 30S
ONCE AGAIN. HIGHS ARE ALSO BELOW NORMAL ON SUNDAY WITH UPPER 30S TO
LOWER 40S EXPECTED. MODELS WERE SHOWING SOME MOISTURE SPREADING
NORTH SUN NIGHT OR MON BUT THEY ARE NOW BACKING OFF ON THIS IDEA. SO
THE FORECAST IS NOW LOOKING DRIER OVER THIS PERIOD AS WELL. THE
FORECAST IS ALSO LOOKING DRIER THROUGH MIDWEEK NOW AS THE EURO TRIES
TO BUILD A RIDGE OVER THE PAC NW. 33

&&

.HYDROLOGY...A WARM FRONT LIFTED NORTH INTO SOUTHERN BRITISH
COLUMBIA THIS MORNING WHERE THE HEAVIER RAIN NOW RESIDES. THE
COASTAL RADAR IS PICKING UP SOME STEADY LIGHT RAIN CONCENTRATED
ALONG THE COAST AND W/SW SLOPES OF THE OLYMPICS. UP TO A COUPLE
TENTHS HAS FALLEN THE PAST 3 HOURS OVER THE OLYMPICS WITH THE
RAINFALL RATES CONTINUING A DOWNTREND. RAIN IS ALSO DECREASING
ACROSS THE N CASCADES WHERE UP TO 1 INCH FELL OVERNIGHT. RAIN IS NOW
IN A LULL ACROSS WRN WA AND ANY ADDITIONAL RAIN AMOUNTS SHOULD BE
LESS THAN A HALF INCH AND MOSTLY CONFINED TO THE CASCADES OF
WHATCOM/SKAGIT COUNTIES AND THE OLYMPICS. BECAUSE RAINFALL HAS
TAPERED...THE ODDS OF THE NOOKSACK AT CEDARVILLE REACHING FLOOD
TODAY ARE LOW BUT STILL NEEDS TO BE WATCHED. THE STILLAGUAMISH
REACHED FLOOD OVERNIGHT BUT IS ON THE DOWNTURN AND SHOULD FALL BELOW
FLOOD LATER TODAY.

THE SNOQUALMIE RIVER AT THE FALLS CRESTED EARLY THIS MORNING WITH
THE CREST MOVING DOWNSTREAM THROUGH CARNATION LATE THIS AFTERNOON.
FLOODING ON THE SNOQUALMIE WILL CONTINUE THROUGH TONIGHT. THE
SKYKOMISH RIVER RAN WITHIN A FOOT OF FLOOD STAGE EARLIER THIS
MORNING BUT IS NOW ON THE DOWNTURN. THE SNOHOMISH...WHICH IS FORMED
BY THE CONFLUENCE OF THE SKYKOMISH AND SNOQUALMIE RIVERS...COULD
HAVE SOME FLOODING LATER TODAY.

THE RIVERS THAT FLOW OFF MOUNT RAINIER ARE RECEDING. THE FLOODING
HAS ENDED FOR THE CARBON AND NISQUALLY RIVERS...BUT FLOODING WILL
CONTINUE FOR THE COWLITZ AND REACH OF THE PUYALLUP NEAR ORTING.

ANOTHER FRONT WILL BRING RENEWED RAINFALL TO WRN WA TONIGHT AND
THURSDAY...LOCALLY HEAVY IN THE MOUNTAINS. THE OLYMPICS AND NORTH
CASCADES WILL RECEIVE THE HEAVIEST RAINFALL...BUT LOCALLY UP TO 5
INCHES OVER MOUNT RAINIER AND SKYKOMISH-SNOQUALMIE-TOLT-SNOHOMISH
BASIN IS POSSIBLE TOO. THE SNOW LEVEL WILL BE 5500 TO 7000 FT FOR
MOST OF THE EVENT...THEN FALL ON FRIDAY AS A COLD FRONT MOVES
THROUGH FROM THE NORTHWEST AND PRECIPITATION DECREASES.

A MAJOR FLOODING EPISODE IS UNLIKELY...BUT THE RAINFALL COULD
CERTAINLY RENEW FLOODING ON THE RIVERS THAT FLOODED OR ALMOST
FLOODED AND SOME OTHER RIVERS COULD REACH FLOOD STAGE AS WELL. A
FLOOD WATCH REMAINS IN EFFECT THROUGH FRIDAY...WHICH INCLUDES ALL
THE COUNTIES WITH RIVERS FLOWING OFF THE WEST SLOPES OF THE CASCADES
AND MASON COUNTY FOR THE POSSIBILITY OF A FLOOD ON THE SKOKOMISH.

COLDER AND DRIER WEATHER IS LIKELY THIS WEEKEND...SO RIVERS SHOULD
RECEDE AND THE FLOOD THREAT WILL END FOR THE FORESEEABLE FUTURE.

MERCER

&&

.AVIATION...DELAYED...THE WARM FRONT THAT BROUGHT ALL THE RAIN TO
WESTERN WASHINGTON THE PAST COUPLE DAYS HAS MOVED INTO BRITISH
COLUMBIA. HOWEVER A WARM MOIST AIR MASS REMAINS OVER WESTERN
WASHINGTON WITH WIDESPREAD LOW-END MVFR TO IFR
CONDITIONS...INCLUDING SOME VISIBILITIES BELOW 3SM IN FOG AND LIGHT
PRECIPITATION.

IMPROVEMENT TODAY WILL BE GRADUAL AND MAINLY LIMITED TO THE PUGET
SOUND REGION AND SOUTHWEST INTERIOR. ANOTHER VIGOROUS FRONTAL SYSTEM
WILL BRING MORE RAIN TO THE COAST LATE TODAY...SPREADING INTO THE
WESTERN WASHINGTON INTERIOR THIS EVENING. WHATEVER IMPROVEMENT
OCCURS TODAY IS LIKELY TO BE QUICKLY UNDONE AS A RESULT.

KSEA...SOUTH WIND MOSTLY 10-16 KT GUSTING 24 KT THROUGH TONIGHT...
EXCEPT THERE COULD BE A BRIEF LULL LATE THIS MORNING AND AFTERNOON.
THE GRADUAL IMPROVEMENT IN CEILINGS SHOULD CONTINUE TODAY...BUT
CONDITIONS WILL DETERIORATE TONIGHT AS THE NEXT FRONTAL SYSTEM
ARRIVES.   MCDONNAL

&&

.MARINE...DELAYED...A COLD FRONT WILL APPROACH THE WATERS TODAY AND
MOVE ONSHORE TONIGHT. SMALL CRAFT ADVISORY SOUTHERLY WINDS WILL BE
COMMON MOST WATERS TODAY...THEN GALES FOR SOME WATERS TONIGHT AS THE
FRONT MOVES THROUGH. MODERATE TO STRONG ONSHORE FLOW WILL PREVAIL
BEHIND THE FRONT ON THURSDAY.

ANOTHER COLD FRONT WILL MOVE THROUGH THE WATERS ON FRIDAY. THIS
FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND MODERATE NORTHERLY WINDS OVER THE OTHER WATERS
LATER FRIDAY INTO SATURDAY. SCHNEIDER

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES AND WARNINGS IN EFFECT FOR PORTIONS OF
     WESTERN WASHINGTON.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
    .SMALL CRAFT ADVISORY GRAYS HARBOR BAR FOR ROUGH BAR.
    .GALE WARNING COASTAL WATERS...ENTRANCES STRAIT OF JUAN DE
     FUCA...AND NORTHERN INLAND WATERS LATE THIS AFTERNOON AND
     TONIGHT.

&&

$$

WWW.WEATHER.GOV/SEATTLE

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000
FXUS66 KSEW 261104
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
330 AM PST WED NOV 26 2014

.SYNOPSIS...A WARM FRONT WILL REMAIN NEAR THE CANADIAN BORDER TODAY.
A COLD FRONT WILL MOVE ACROSS THE AREA TONIGHT FOR MORE RAIN
AND WINDY CONDITIONS. RAIN WILL CONTINUE ON THANKSGIVING DAY AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH THEN CROSSES THE AREA
ON FRIDAY. COOL DRY AND BREEZY WEATHER WILL DEVELOP BY FRIDAY
AFTERNOON AND CONTINUE THROUGH THE WEEKEND AS HIGH PRESSURE BUILDS
OVER BRITISH COLUMBIA.

&&

.SHORT TERM...WESTERN WASHINGTON IS IN THE WARM SECTOR AS A WARM
FRONT LIFTED NORTH THROUGH THE REGION OVERNIGHT. AS A RESULT...TEMPS
REMAINED MILD WITH READINGS MAINLY IN THE 50S THIS MORNING. THE WARM
FRONT IS OVER SOUTHERN B.C. NOW AND RAIN WILL MAINLY AFFECT THE
NORTHERN EDGE OF THE CWA TODAY...AND ALSO THE MOUNTAINS. RIVERS ARE
STILL RISING AND FLOOD WATCHES AND WARNING ARE IN EFFECT...SEE
HYDROLOGY DISCUSSION BELOW. TEMPS WILL REMAIN MILD THIS AFTERNOON
WITH HIGHS IN THE MID TO UPPER 50S.

RAIN WILL INCREASE IN COVERAGE TONIGHT THROUGH THURSDAY AS A COLD
FRONT MOVES INLAND. SE PRESSURE GRADIENTS WILL TIGHTEN AS THIS
SYSTEM APPROACHES AND MAY SEE WIND ADVISORY SPEEDS ALONG THE COAST
AND NORTH INTERIOR ZONES TONIGHT. THIS FRONT WILL BRING ANOTHER SHOT
OF HEAVY RAIN TO THE MOUNTAINS...LEADING TO MORE FLOOD CONCERNS.
SNOW LEVELS WILL REMAIN HIGH AT 6000 TO 7000 FT. EXPECT RAIN AT
TIMES IN THE LOWLANDS THROUGHOUT THANKSGIVING DAY.

ANOTHER COLD FRONT WILL CROSS FROM NW TO SE THROUGH WESTERN WA ON
FRIDAY...BRINGING MORE RAIN AND WINDY CONDITIONS. THIS FRONT SHOULD
EXIT SOUTH FRI AFTERNOON. MODELS ARE SHOWING GUSTY FRASER RIVER
OUTFLOW WINDS FRI AFTERNOON OR EVENING AS STRONG HIGH PRES OVER
INTERIOR B.C. SAGS SOUTH. THIS COOL AND DRY AIR WILL FILTER SOUTH
INTO WESTERN WA FRI NIGHT. THE AIR MASS WILL BE COOL AND UNSTABLE AS
A DEEP UPPER TROUGH ALSO CLIPS WESTERN WA DURING THIS PERIOD. THERE
IS A CHANCE OF SNOW IN THE INTERIOR FRI NIGHT INTO SAT MORNING AS
THIS TROUGH CROSSES THE REGION. MODELS ARE NOW TRYING TO FORM A
CONVERGENCE ZONE WHERE COOL NORTHERLY FRASER OUTFLOW MEETS THE MOIST
S/SW ONSHORE FLOW. COULD SEE RAIN/SNOW IN THE CONVERGENCE ZONE. BUT
THIS COULD OCCUR ANYWHERE IN THE INTERIOR. TOUGH TO PIN THIS DOWN
EXACTLY BUT DEFINITELY NEED TO KEEP A CLOSE EYE IF THIS SCENARIO
PANS OUT. MODELS DO SHOW THE TROUGH EXITING SAT MORNING WITH DRY
WEATHER EXPECTED. 33

.LONG TERM...LONG RANGE MODELS SHOW A COOL AND DRY AIR MASS OVER
WESTERN WA ON SUNDAY. HIGH PRES OVER INTERIOR B.C. WILL MAINTAIN
EASTERLY FLOW THROUGH THE PASSES. LOWS SUNDAY MORNING WILL BE DOWN
TO THE 20S TO LOWER 30S ONCE AGAIN. HIGHS ARE ALSO BELOW NORMAL ON
SUNDAY WITH UPPER 30S TO LOWER 40S EXPECTED. MODELS WERE SHOWING
SOME MOISTURE SPREADING NORTH SUN NIGHT OR MON BUT THEY ARE NOW
BACKING OFF ON THIS IDEA. SO THE FORECAST IS NOW LOOKING DRIER OVER
THIS PERIOD AS WELL. THE FORECAST IS ALSO LOOKING DRIER THROUGH
MIDWEEK NOW AS THE EURO TRIES TO BUILD A RIDGE OVER THE PAC NW. 33

&&

.HYDROLOGY...RAIN RATES HAVE DECREASED THROUGHOUT THE CASCADES
OVERNIGHT...WHILE THE WARM FRONT HAS CONTINUED MOVING SLOWLY
NORTHWARD. RAINFALL AMOUNTS OF 0.5 TO 1.2 INCHES DURING THE PAST 6
HOURS WERE STILL COMMON FROM THE STILLAGUAMISH BASIN NORTHWARD...BUT
RATES THERE SHOULD DECREASE THIS MORNING. THE STILLAGUAMISH REACHED
FLOOD STAGE EARLY THIS MORNING...AND FLOODING IS STILL A SHORT TERM
CONCERN FOR THE NOOKSACK RIVER.

THERE HAS NOT BEEN MUCH RAIN OVERNIGHT SOUTH OF THE STILLAGUAMISH
BASIN -- GENERALLY 0.5 INCH OR LESS. THE THREE FORKS OF THE
SNOQUALMIE RIVER APPEAR TO HAVE CRESTED...SO THE SNOQUALMIE AT THE
FALLS SHOULD CREST EARLY THIS MORNING WITH THE CREST MOVING
DOWNSTREAM THROUGH CARNATION LATE THIS AFTERNOON. FLOODING ON THE
SNOQUALMIE WILL CONTINUE THROUGH TONIGHT. THE SKYKOMISH RIVER HAS
BEEN RUNNING WITHIN A FOOT OF FLOOD STAGE...BUT IT WILL PROBABLY
BEGIN FALLING SOON. THE SNOHOMISH...WHICH IS FORMED BY THE
CONFLUENCE OF THE SKYKOMISH AND SNOQUALMIE RIVERS...COULD HAVE SOME
FLOODING LATER TODAY.

THE RIVERS THAT FLOW OFF MOUNT RAINIER ARE RECEDING. THE FLOODING
HAS ENDED FOR THE CARBON AND NISQUALLY RIVERS...BUT FLOODING WILL
CONTINUE FOR THE COWLITZ AND REACH OF THE PUYALLUP NEAR ORTING.

NEXT WE TURN OUR ATTENTION TO THE FRONTAL SYSTEM THAT WILL BRING
SIGNIFICANT RAINFALL TONIGHT THROUGH THURSDAY NIGHT. WE ARE
EXPECTING STORM TOTALS IN THE MOUNTAINS OF 3 TO 5 INCHES DURING THE
36 HOURS FROM 4 PM TODAY THROUGH 4 AM FRIDAY. THE OLYMPICS AND NORTH
CASCADES WILL RECEIVE THE HEAVIEST RAINFALL...BUT LOCALLY UP TO 5
INCHES OVER MOUNT RAINIER AND SKYKOMISH-SNOQUALMIE-TOLT-SNOHOMISH
BASIN IS POSSIBLE TOO. THE SNOW LEVEL WILL BE 5500 TO 7000 FT FOR
MOST OF THE EVENT...THEN FALL ON FRIDAY AS A COLD FRONT MOVES
THROUGH FROM THE NORTHWEST AND PRECIPITATION DECREASES.

A MAJOR FLOODING EPISODE IS UNLIKELY...BUT THE RAINFALL COULD
CERTAINLY RENEW FLOODING ON THE RIVERS THAT FLOODED OR ALMOST
FLOODED AND SOME OTHER RIVERS COULD REACH FLOOD STAGE AS WELL. A
FLOOD WATCH IS IN EFFECT THROUGH FRIDAY...WHICH INCLUDES ALL THE
COUNTIES WITH RIVERS FLOWING OFF THE WEST SLOPES OF THE CASCADES AND
MASON COUNTY FOR THE POSSIBILITY OF A FLOOD ON THE SKOKOMISH.

COLDER AND DRIER WEATHER IS LIKELY THIS WEEKEND...SO RIVERS SHOULD
RECEDE AND THE FLOOD THREAT WILL END FOR THE FORESEEABLE FUTURE.
MCDONNAL

&&

.AVIATION...THE WARM FRONT THAT BROUGHT ALL THE RAIN TO WESTERN
WASHINGTON THE PAST COUPLE DAYS HAS MOVED INTO BRITISH COLUMBIA.
HOWEVER A WARM MOIST AIR MASS REMAINS OVER WESTERN WASHINGTON WITH
WIDESPREAD LOW-END MVFR TO IFR CONDITIONS...INCLUDING SOME
VISIBILITIES BELOW 3SM IN FOG AND LIGHT PRECIPITATION.

IMPROVEMENT TODAY WILL BE GRADUAL AND MAINLY LIMITED TO THE PUGET
SOUND REGION AND SOUTHWEST INTERIOR. ANOTHER VIGOROUS FRONTAL SYSTEM
WILL BRING MORE RAIN TO THE COAST LATE TODAY...SPREADING INTO THE
WESTERN WASHINGTON INTERIOR THIS EVENING. WHATEVER IMPROVEMENT
OCCURS TODAY IS LIKELY TO BE QUICKLY UNDONE AS A RESULT.

KSEA...SOUTH WIND MOSTLY 10-16 KT GUSTING 24 KT THROUGH TONIGHT...
EXCEPT THERE COULD BE A BRIEF LULL LATE THIS MORNING AND AFTERNOON.
THE GRADUAL IMPROVEMENT IN CEILINGS SHOULD CONTINUE TODAY...BUT
CONDITIONS WILL DETERIORATE TONIGHT AS THE NEXT FRONTAL SYSTEM
ARRIVES.   MCDONNAL

&&

.MARINE...A COLD FRONT WILL APPROACH THE WATERS TODAY AND MOVE
ONSHORE TONIGHT. SMALL CRAFT ADVISORY SOUTHERLY WINDS WILL BE COMMON
MOST WATERS TODAY...THEN GALES FOR SOME WATERS TONIGHT AS THE FRONT
MOVES THROUGH. MODERATE TO STRONG ONSHORE FLOW WILL PREVAIL BEHIND
THE FRONT ON THURSDAY.

ANOTHER COLD FRONT WILL MOVE THROUGH THE WATERS ON FRIDAY. THIS
FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND MODERATE NORTHERLY WINDS OVER THE OTHER WATERS
LATER FRIDAY INTO SATURDAY. SCHNEIDER

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES AND WARNINGS IN EFFECT FOR PORTIONS OF
     WESTERN WASHINGTON.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
    .SMALL CRAFT ADVISORY GRAYS HARBOR BAR FOR ROUGH BAR.
    .GALE WARNING COASTAL WATERS...ENTRANCES STRAIT OF JUAN DE
     FUCA...AND NORTHERN INLAND WATERS LATE THIS AFTERNOON AND
     TONIGHT.

&&

$$

WWW.WEATHER.GOV/SEATTLE

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000
FXUS66 KSEW 261104
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
330 AM PST WED NOV 26 2014

.SYNOPSIS...A WARM FRONT WILL REMAIN NEAR THE CANADIAN BORDER TODAY.
A COLD FRONT WILL MOVE ACROSS THE AREA TONIGHT FOR MORE RAIN
AND WINDY CONDITIONS. RAIN WILL CONTINUE ON THANKSGIVING DAY AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH THEN CROSSES THE AREA
ON FRIDAY. COOL DRY AND BREEZY WEATHER WILL DEVELOP BY FRIDAY
AFTERNOON AND CONTINUE THROUGH THE WEEKEND AS HIGH PRESSURE BUILDS
OVER BRITISH COLUMBIA.

&&

.SHORT TERM...WESTERN WASHINGTON IS IN THE WARM SECTOR AS A WARM
FRONT LIFTED NORTH THROUGH THE REGION OVERNIGHT. AS A RESULT...TEMPS
REMAINED MILD WITH READINGS MAINLY IN THE 50S THIS MORNING. THE WARM
FRONT IS OVER SOUTHERN B.C. NOW AND RAIN WILL MAINLY AFFECT THE
NORTHERN EDGE OF THE CWA TODAY...AND ALSO THE MOUNTAINS. RIVERS ARE
STILL RISING AND FLOOD WATCHES AND WARNING ARE IN EFFECT...SEE
HYDROLOGY DISCUSSION BELOW. TEMPS WILL REMAIN MILD THIS AFTERNOON
WITH HIGHS IN THE MID TO UPPER 50S.

RAIN WILL INCREASE IN COVERAGE TONIGHT THROUGH THURSDAY AS A COLD
FRONT MOVES INLAND. SE PRESSURE GRADIENTS WILL TIGHTEN AS THIS
SYSTEM APPROACHES AND MAY SEE WIND ADVISORY SPEEDS ALONG THE COAST
AND NORTH INTERIOR ZONES TONIGHT. THIS FRONT WILL BRING ANOTHER SHOT
OF HEAVY RAIN TO THE MOUNTAINS...LEADING TO MORE FLOOD CONCERNS.
SNOW LEVELS WILL REMAIN HIGH AT 6000 TO 7000 FT. EXPECT RAIN AT
TIMES IN THE LOWLANDS THROUGHOUT THANKSGIVING DAY.

ANOTHER COLD FRONT WILL CROSS FROM NW TO SE THROUGH WESTERN WA ON
FRIDAY...BRINGING MORE RAIN AND WINDY CONDITIONS. THIS FRONT SHOULD
EXIT SOUTH FRI AFTERNOON. MODELS ARE SHOWING GUSTY FRASER RIVER
OUTFLOW WINDS FRI AFTERNOON OR EVENING AS STRONG HIGH PRES OVER
INTERIOR B.C. SAGS SOUTH. THIS COOL AND DRY AIR WILL FILTER SOUTH
INTO WESTERN WA FRI NIGHT. THE AIR MASS WILL BE COOL AND UNSTABLE AS
A DEEP UPPER TROUGH ALSO CLIPS WESTERN WA DURING THIS PERIOD. THERE
IS A CHANCE OF SNOW IN THE INTERIOR FRI NIGHT INTO SAT MORNING AS
THIS TROUGH CROSSES THE REGION. MODELS ARE NOW TRYING TO FORM A
CONVERGENCE ZONE WHERE COOL NORTHERLY FRASER OUTFLOW MEETS THE MOIST
S/SW ONSHORE FLOW. COULD SEE RAIN/SNOW IN THE CONVERGENCE ZONE. BUT
THIS COULD OCCUR ANYWHERE IN THE INTERIOR. TOUGH TO PIN THIS DOWN
EXACTLY BUT DEFINITELY NEED TO KEEP A CLOSE EYE IF THIS SCENARIO
PANS OUT. MODELS DO SHOW THE TROUGH EXITING SAT MORNING WITH DRY
WEATHER EXPECTED. 33

.LONG TERM...LONG RANGE MODELS SHOW A COOL AND DRY AIR MASS OVER
WESTERN WA ON SUNDAY. HIGH PRES OVER INTERIOR B.C. WILL MAINTAIN
EASTERLY FLOW THROUGH THE PASSES. LOWS SUNDAY MORNING WILL BE DOWN
TO THE 20S TO LOWER 30S ONCE AGAIN. HIGHS ARE ALSO BELOW NORMAL ON
SUNDAY WITH UPPER 30S TO LOWER 40S EXPECTED. MODELS WERE SHOWING
SOME MOISTURE SPREADING NORTH SUN NIGHT OR MON BUT THEY ARE NOW
BACKING OFF ON THIS IDEA. SO THE FORECAST IS NOW LOOKING DRIER OVER
THIS PERIOD AS WELL. THE FORECAST IS ALSO LOOKING DRIER THROUGH
MIDWEEK NOW AS THE EURO TRIES TO BUILD A RIDGE OVER THE PAC NW. 33

&&

.HYDROLOGY...RAIN RATES HAVE DECREASED THROUGHOUT THE CASCADES
OVERNIGHT...WHILE THE WARM FRONT HAS CONTINUED MOVING SLOWLY
NORTHWARD. RAINFALL AMOUNTS OF 0.5 TO 1.2 INCHES DURING THE PAST 6
HOURS WERE STILL COMMON FROM THE STILLAGUAMISH BASIN NORTHWARD...BUT
RATES THERE SHOULD DECREASE THIS MORNING. THE STILLAGUAMISH REACHED
FLOOD STAGE EARLY THIS MORNING...AND FLOODING IS STILL A SHORT TERM
CONCERN FOR THE NOOKSACK RIVER.

THERE HAS NOT BEEN MUCH RAIN OVERNIGHT SOUTH OF THE STILLAGUAMISH
BASIN -- GENERALLY 0.5 INCH OR LESS. THE THREE FORKS OF THE
SNOQUALMIE RIVER APPEAR TO HAVE CRESTED...SO THE SNOQUALMIE AT THE
FALLS SHOULD CREST EARLY THIS MORNING WITH THE CREST MOVING
DOWNSTREAM THROUGH CARNATION LATE THIS AFTERNOON. FLOODING ON THE
SNOQUALMIE WILL CONTINUE THROUGH TONIGHT. THE SKYKOMISH RIVER HAS
BEEN RUNNING WITHIN A FOOT OF FLOOD STAGE...BUT IT WILL PROBABLY
BEGIN FALLING SOON. THE SNOHOMISH...WHICH IS FORMED BY THE
CONFLUENCE OF THE SKYKOMISH AND SNOQUALMIE RIVERS...COULD HAVE SOME
FLOODING LATER TODAY.

THE RIVERS THAT FLOW OFF MOUNT RAINIER ARE RECEDING. THE FLOODING
HAS ENDED FOR THE CARBON AND NISQUALLY RIVERS...BUT FLOODING WILL
CONTINUE FOR THE COWLITZ AND REACH OF THE PUYALLUP NEAR ORTING.

NEXT WE TURN OUR ATTENTION TO THE FRONTAL SYSTEM THAT WILL BRING
SIGNIFICANT RAINFALL TONIGHT THROUGH THURSDAY NIGHT. WE ARE
EXPECTING STORM TOTALS IN THE MOUNTAINS OF 3 TO 5 INCHES DURING THE
36 HOURS FROM 4 PM TODAY THROUGH 4 AM FRIDAY. THE OLYMPICS AND NORTH
CASCADES WILL RECEIVE THE HEAVIEST RAINFALL...BUT LOCALLY UP TO 5
INCHES OVER MOUNT RAINIER AND SKYKOMISH-SNOQUALMIE-TOLT-SNOHOMISH
BASIN IS POSSIBLE TOO. THE SNOW LEVEL WILL BE 5500 TO 7000 FT FOR
MOST OF THE EVENT...THEN FALL ON FRIDAY AS A COLD FRONT MOVES
THROUGH FROM THE NORTHWEST AND PRECIPITATION DECREASES.

A MAJOR FLOODING EPISODE IS UNLIKELY...BUT THE RAINFALL COULD
CERTAINLY RENEW FLOODING ON THE RIVERS THAT FLOODED OR ALMOST
FLOODED AND SOME OTHER RIVERS COULD REACH FLOOD STAGE AS WELL. A
FLOOD WATCH IS IN EFFECT THROUGH FRIDAY...WHICH INCLUDES ALL THE
COUNTIES WITH RIVERS FLOWING OFF THE WEST SLOPES OF THE CASCADES AND
MASON COUNTY FOR THE POSSIBILITY OF A FLOOD ON THE SKOKOMISH.

COLDER AND DRIER WEATHER IS LIKELY THIS WEEKEND...SO RIVERS SHOULD
RECEDE AND THE FLOOD THREAT WILL END FOR THE FORESEEABLE FUTURE.
MCDONNAL

&&

.AVIATION...THE WARM FRONT THAT BROUGHT ALL THE RAIN TO WESTERN
WASHINGTON THE PAST COUPLE DAYS HAS MOVED INTO BRITISH COLUMBIA.
HOWEVER A WARM MOIST AIR MASS REMAINS OVER WESTERN WASHINGTON WITH
WIDESPREAD LOW-END MVFR TO IFR CONDITIONS...INCLUDING SOME
VISIBILITIES BELOW 3SM IN FOG AND LIGHT PRECIPITATION.

IMPROVEMENT TODAY WILL BE GRADUAL AND MAINLY LIMITED TO THE PUGET
SOUND REGION AND SOUTHWEST INTERIOR. ANOTHER VIGOROUS FRONTAL SYSTEM
WILL BRING MORE RAIN TO THE COAST LATE TODAY...SPREADING INTO THE
WESTERN WASHINGTON INTERIOR THIS EVENING. WHATEVER IMPROVEMENT
OCCURS TODAY IS LIKELY TO BE QUICKLY UNDONE AS A RESULT.

KSEA...SOUTH WIND MOSTLY 10-16 KT GUSTING 24 KT THROUGH TONIGHT...
EXCEPT THERE COULD BE A BRIEF LULL LATE THIS MORNING AND AFTERNOON.
THE GRADUAL IMPROVEMENT IN CEILINGS SHOULD CONTINUE TODAY...BUT
CONDITIONS WILL DETERIORATE TONIGHT AS THE NEXT FRONTAL SYSTEM
ARRIVES.   MCDONNAL

&&

.MARINE...A COLD FRONT WILL APPROACH THE WATERS TODAY AND MOVE
ONSHORE TONIGHT. SMALL CRAFT ADVISORY SOUTHERLY WINDS WILL BE COMMON
MOST WATERS TODAY...THEN GALES FOR SOME WATERS TONIGHT AS THE FRONT
MOVES THROUGH. MODERATE TO STRONG ONSHORE FLOW WILL PREVAIL BEHIND
THE FRONT ON THURSDAY.

ANOTHER COLD FRONT WILL MOVE THROUGH THE WATERS ON FRIDAY. THIS
FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND MODERATE NORTHERLY WINDS OVER THE OTHER WATERS
LATER FRIDAY INTO SATURDAY. SCHNEIDER

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES AND WARNINGS IN EFFECT FOR PORTIONS OF
     WESTERN WASHINGTON.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
    .SMALL CRAFT ADVISORY GRAYS HARBOR BAR FOR ROUGH BAR.
    .GALE WARNING COASTAL WATERS...ENTRANCES STRAIT OF JUAN DE
     FUCA...AND NORTHERN INLAND WATERS LATE THIS AFTERNOON AND
     TONIGHT.

&&

$$

WWW.WEATHER.GOV/SEATTLE

YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML







000
FXUS66 KSEW 260530
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
930 PM PST TUE NOV 25 2014

.SYNOPSIS...A WARM FRONT WILL REMAIN NEAR THE CANADIAN BORDER
TONIGHT AND WEDNESDAY WITH RAIN AT TIMES OVER THE NORTH PART AND
RAIN LIKELY ELSEWHERE TONIGHT. RAIN WILL DIMINISH WITH JUST A CHANCE
OF RAIN ON WEDNESDAY. A FRONT WILL MOVE ACROSS THE AREA WEDNESDAY
NIGHT FOR MORE RAIN AND WINDY CONDITIONS. RAIN WILL CONTINUE ON
THANKSGIVING DAY AS ANOTHER COLD FRONT APPROACHES FROM THE NORTH
THEN CROSSES THE AREA THURSDAY NIGHT. COOL DRY AND BREEZY WEATHER
WILL DEVELOP BY FRIDAY AFTERNOON AND CONTINUE THROUGH THE WEEKEND AS
HIGH PRESSURE BUILDS OVER BRITISH COLUMBIA. WEAK WEATHER SYSTEMS MAY
BRING A LITTLE RAIN EARLY NEXT WEEK.

&&

.SHORT TERM...THE SURFACE WARM FRONT IS JUST NORTH OF PUGET SOUND AT
8 PM WITH SLY WINDS INCREASING S OF THE FRONT AND REMAINING MAINLY
LIGHT FROM NEAR THE E ENTRANCE TO THE N INTERIOR. ALKI WAS REPORTING
WIND GUSTS TO 43 KT THIS PAST HOUR AND OTHER OBS SITES AROUND THE
SOUND ARE GUSTY AS WELL. RAIN WILL PERSIST TO THE N OF THE FRONT SO
ANOTHER INCH OR LOCALLY 2 INCHES IS POSSIBLE TONIGHT IN THE N
CASCADES. THE WARM FRONT SHOULD LIFT N OF THE WA/B.C. BORDER BY
WEDNESDAY MORNING WITH THE BULK OF MOISTURE TO THE N OF WA. THERE
WILL BE SOME RAIN AT TIMES IN THE OLYMPICS AND AREAS N OF PUGET
SOUND AND THE CASCADES BUT AMOUNTS DO NOT LOOK HYDROLOGICALLY
SIGNIFICANT.

RAIN WILL PICK UP AGAIN WEDNESDAY NIGHT INTO THURSDAY AS A STRONG
COLD FRONT PUSHES INTO WRN WA. THE STRONG SW FLOW ALOFT WILL FAVOR
HEAVIER RAIN ALONG S/SW FACING SLOPES OF THE OLYMPICS AND N
CASCADES. 3 TO 5 INCHES OF RAIN COULD FALL RENEWING THE FLOOD THREAT
FOR THE SKOKOMISH BASIN AND ALSO PRONE RIVERS IN THE N CASCADES.
SEE THE HYDRO DISCUSSION FOR DETAILS. IT WILL ALSO RAIN ACROSS THE
LOWLANDS BUT THE STRONG SW FLOW WILL PROBABLY SHADOW PORTIONS OF
PUGET SOUND WITH LESS RAINFALL AMOUNTS EXPECTED.

MODELS HAVE TRENDED TOWARD A SECOND FRONTAL BOUNDARY HANGING UP OVER
THE AREA ON FRIDAY. THIS IS AHEAD OF A COLDER AIR MASS OVER B.C.
TRYING TO PUSH SWD. THE WLY FLOW WHICH STARTS OFF STRONG DURING THE
MORNING WILL WEAKEN CONSIDERABLY THROUGH THE DAY. THIS WILL LIMIT
OROGRAPHIC ENHANCEMENT ALONG THE CASCADES. WHILE AN INCH OR TWO IS
POSSIBLE ACROSS THE NRN PART OF THE FORECAST AREA...THE IMPACT ON
RIVERS WILL PROBABLY BE MINIMAL. WILL NEED TO LOOK OVER ALL THE 00Z
RUNS BEFORE MAKING ANY ADJUSTMENTS TO QPF.

COLDER AIR WILL BE DAMMING UP ALONG THE CANADIAN ROCKIES LATER
FRIDAY AND FRIDAY NIGHT. FRASER OUTFLOW IS EXPECTED TO DEVELOP AND
COLDER AIR ALOFT WILL ALSO START TO FILTER INTO THE AREA. SOME
MODELS SHOW RESIDUAL MOISTURE IN PLACE...LOW LEVEL CONVERGENCE...AND
COLDER AIR FILTERING IN. WILL NEED TO WATCH THIS SITUATION CLOSELY
AS THIS SET UP CAN SOMETIMES RESULT IN LOCALIZED LOWLAND SNOW. WILL
REVIEW THIS POTENTIAL FOR THE MORNING FORECAST ISSUANCE.

.LONG TERM...FROM PREVIOUS DISCUSSION...BASED ON AGREEMENT BETWEEN
THE 12Z GFS AND 12Z ECMWF SATURDAY AND SUNDAY WERE CLEARED OUT AND
THE MENTION OF RAIN DROPPED...EXCEPT FOR THE S PART LATE SUNDAY.
WITH COOL DRY N FLOW ALOFT OVER THE AREA AND COLD DRY NE FLOW FROM
THE FRASER VALLEY...SKIES WILL BE MOSTLY SUNNY...TEMPERATURES
COOL...AND N-NE WINDS BREEZY. LOWS WILL DROP INTO THE 20S SATURDAY
NIGHT WITH HIGHS SATURDAY AND SUNDAY IN THE UPPER 30S TO MID 40S.
HOWEVER...CONFIDENCE IN THE MODELS IS STILL RATHER LOW...AND THE 18Z
GFS HAS JUST REVERSED COURSE AND BRINGS RAIN UP FROM OREGON ON
SUNDAY. THE ECMWF HAS BEEN MORE CONSISTENT SO REMAINS THE PREFERRED
SOLUTION. THE ECMWF BRINGS MOISTURE AND RAIN NORTHWARD FROM OREGON
SUNDAY NIGHT.  WITH COLD AIR IN PLACE OVER W WA THERE MAY BE A
CHANCE OF SOME LIGHT SNOW...PARTICULARLY OVER THE NORTHERN ZONES AS
THE PRECIP MOVES NORTH. SO FAR THIS IS NOT ACCOUNTED FOR IN THE
FORECASTS AND WILL HAVE TO BE RE-EVALUATED ONCE MODEL CONSISTENCY
AND AGREEMENT IMPROVES. KAM

&&

.HYDROLOGY...THE AREA OF HEAVIEST RAIN IN THE CASCADES EXTENDED FROM
THE SNOQUALMIE BASIN TO THE NORTH CASCADES THIS EVENING...AND IT
CONTINUES TO SHIFT SLOWLY NORTHWARD. THE HEAVIEST RAIN FOR THE EVENT
SO FAR HAS OCCURRED IN THE MOUNT RAINIER AREA...WHERE LOCALLY UP TO
7 INCHES HAS FALLEN SINCE MONDAY AFTERNOON. THE COWLITZ... NISQUALLY
AND CARBON RIVERS ALL FLOODED. THAT AREA WILL ONLY RECEIVE ANOTHER
INCH OR SO OF RAIN TONIGHT AND WEDNESDAY. THE NISQUALLY AND CARBON
RIVERS HAVE RECEDED BELOW FLOOD STAGE...AND THE COWLITZ AT RANDLE
WILL CREST LATE THIS EVENING.

UP TO 5 INCHES OF RAIN HAS FALLEN OVER THE BASINS OF THE CENTRAL AND
NORTH CASCADES...BUT SO FAR ONLY THE SNOQUALMIE RIVER IS FLOODING.
MORE HEAVY RAIN WILL FALL IN THIS AREA TONIGHT AS THE BAROCLINIC
BAND SHIFTS NORTHWARD...WITH ANOTHER 1 TO 3 INCHES LIKELY AS THE
SNOW LEVEL REMAINS 7000 TO 8000 FT. SO OTHER RIVERS COULD STILL
FLOOD...AND IN FACT THE UPPER REACHES OF THE SNOQUALMIE AND
SKYKOMISH HAVE STARTED RISING AGAIN. IN ADDITION THE ELWHA
RIVER...FLOWING OFF THE NORTH SIDE OF THE OLYMPICS...IS RISING MORE
QUICKLY THAN EXPECTED AND IT WILL NEED WATCHING FOR THE NEXT SEVERAL
HOURS.

THE NEXT FRONTAL SYSTEM WILL BRING ANOTHER ROUND OF HEAVY RAIN
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...RENEWING THE POSSIBILITY OF
FLOODING ON CASCADES RIVERS AND ALSO PERHAPS DRIVING THE SKOKOMISH
RIVER ABOVE FLOOD STAGE. THERE WILL PROBABLY BE 3 TO 6 INCHES OF
RAIN...WITH THE OLYMPICS AND NORTH CASCADES RECEIVING THE HEAVIEST
AMOUNTS. THE SNOW LEVEL WILL BE 5500 TO 7000 FT.   MCDONNAL

&&

.AVIATION...A WARM FRONT JUST NORTH OF PUGET SOUND WILL LIFT TOWARD
THE B.C. BORDER BY WEDNESDAY MORNING. STRONG SW FLOW ALOFT WILL
PERSIST THROUGH WEDNESDAY. STABLE AND MOIST CONDITIONS WILL PERSIST
BUT RAIN WILL BECOME MORE SPOTTY IN NATURE. A FRONT WILL PUSH INTO
WRN WA WEDNESDAY NIGHT.

IFR CEILINGS AND VISIBILITIES HAVE BEEN STUBBORN TO IMPROVE NORTH OF
THE FRONT...BUT AFTER THE FRONT PASSES CEILINGS SHOULD LIFT TO LOW
END MVFR AT LEAST...1-2K FT...AND VISIBILITIES WILL IMPROVE TO 4-6SM
BR. LIGHT WINDS AT THE SURFACE WILL INCREASE TONIGHT BEHIND THE
FRONT.

KSEA...MVFR CONDITIONS LIKELY THROUGH SUNDAY WITH LITTLE RAINFALL
EXPECTED DUE TO SHADOWING OFF THE OLYMPICS. SW WINDS 15-20 KT W/
GUSTS 30 KT...EASING TO 10 KT ON WEDNESDAY.

&&

.MARINE...A FRONT NORTH OF PUGET SOUND WILL MOVE INTO SOUTHERN
BRITISH COLUMBIA BY WEDNESDAY MORNING. SMALL CRAFT ADVISORY STRENGTH
WINDS WILL SPREAD NORTH BEHIND THE FRONT...EXCEPT GALE FORCE WINDS
IN PUGET SOUND.

WINDS WILL INCREASE WEDNESDAY AS A COLD FRONT APPROACHES THE COAST.
AT LEAST SMALL CRAFT ADVISORY LEVEL WINDS ARE LIKELY OVER MOST
WATERS WITH GALES POSSIBLE ON THE COAST AND OVER EXPOSED INLAND
AREAS WEDNESDAY NIGHT. A GALE WATCH IS IN EFFECT FOR THE COAST...THE
STRAIT ENTRANCES...AND THE NORTHERN INLAND WATERS WEDNESDAY NIGHT.

ANOTHER COLD FRONT WILL MOVE THROUGH THE WATERS ON FRIDAY. THIS
FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND MODERATE NORTHERLY WINDS OVER THE OTHER WATERS
LATER FRIDAY INTO SATURDAY. CHB/MERCER

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...VARIOUS FLOOD WATCHES AND WARNINGS IN EFFECT FOR PORTIONS OF
     WESTERN WASHINGTON.
PZ...GALE WARNING FOR PUGET SOUND THROUGH 6 AM WEDNESDAY MORNING.
     SMALL CRAFT ADVISORY ALL WATERS EXCEPT EAST ENTRANCE AND PUGET
     SOUND.
     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.
     GALE WATCH COAST...ENTRANCES...AND NORTHERN INLAND WATERS
     WEDNESDAY NIGHT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML

















000
FXUS66 KSEW 260530
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
930 PM PST TUE NOV 25 2014

.SYNOPSIS...A WARM FRONT WILL REMAIN NEAR THE CANADIAN BORDER
TONIGHT AND WEDNESDAY WITH RAIN AT TIMES OVER THE NORTH PART AND
RAIN LIKELY ELSEWHERE TONIGHT. RAIN WILL DIMINISH WITH JUST A CHANCE
OF RAIN ON WEDNESDAY. A FRONT WILL MOVE ACROSS THE AREA WEDNESDAY
NIGHT FOR MORE RAIN AND WINDY CONDITIONS. RAIN WILL CONTINUE ON
THANKSGIVING DAY AS ANOTHER COLD FRONT APPROACHES FROM THE NORTH
THEN CROSSES THE AREA THURSDAY NIGHT. COOL DRY AND BREEZY WEATHER
WILL DEVELOP BY FRIDAY AFTERNOON AND CONTINUE THROUGH THE WEEKEND AS
HIGH PRESSURE BUILDS OVER BRITISH COLUMBIA. WEAK WEATHER SYSTEMS MAY
BRING A LITTLE RAIN EARLY NEXT WEEK.

&&

.SHORT TERM...THE SURFACE WARM FRONT IS JUST NORTH OF PUGET SOUND AT
8 PM WITH SLY WINDS INCREASING S OF THE FRONT AND REMAINING MAINLY
LIGHT FROM NEAR THE E ENTRANCE TO THE N INTERIOR. ALKI WAS REPORTING
WIND GUSTS TO 43 KT THIS PAST HOUR AND OTHER OBS SITES AROUND THE
SOUND ARE GUSTY AS WELL. RAIN WILL PERSIST TO THE N OF THE FRONT SO
ANOTHER INCH OR LOCALLY 2 INCHES IS POSSIBLE TONIGHT IN THE N
CASCADES. THE WARM FRONT SHOULD LIFT N OF THE WA/B.C. BORDER BY
WEDNESDAY MORNING WITH THE BULK OF MOISTURE TO THE N OF WA. THERE
WILL BE SOME RAIN AT TIMES IN THE OLYMPICS AND AREAS N OF PUGET
SOUND AND THE CASCADES BUT AMOUNTS DO NOT LOOK HYDROLOGICALLY
SIGNIFICANT.

RAIN WILL PICK UP AGAIN WEDNESDAY NIGHT INTO THURSDAY AS A STRONG
COLD FRONT PUSHES INTO WRN WA. THE STRONG SW FLOW ALOFT WILL FAVOR
HEAVIER RAIN ALONG S/SW FACING SLOPES OF THE OLYMPICS AND N
CASCADES. 3 TO 5 INCHES OF RAIN COULD FALL RENEWING THE FLOOD THREAT
FOR THE SKOKOMISH BASIN AND ALSO PRONE RIVERS IN THE N CASCADES.
SEE THE HYDRO DISCUSSION FOR DETAILS. IT WILL ALSO RAIN ACROSS THE
LOWLANDS BUT THE STRONG SW FLOW WILL PROBABLY SHADOW PORTIONS OF
PUGET SOUND WITH LESS RAINFALL AMOUNTS EXPECTED.

MODELS HAVE TRENDED TOWARD A SECOND FRONTAL BOUNDARY HANGING UP OVER
THE AREA ON FRIDAY. THIS IS AHEAD OF A COLDER AIR MASS OVER B.C.
TRYING TO PUSH SWD. THE WLY FLOW WHICH STARTS OFF STRONG DURING THE
MORNING WILL WEAKEN CONSIDERABLY THROUGH THE DAY. THIS WILL LIMIT
OROGRAPHIC ENHANCEMENT ALONG THE CASCADES. WHILE AN INCH OR TWO IS
POSSIBLE ACROSS THE NRN PART OF THE FORECAST AREA...THE IMPACT ON
RIVERS WILL PROBABLY BE MINIMAL. WILL NEED TO LOOK OVER ALL THE 00Z
RUNS BEFORE MAKING ANY ADJUSTMENTS TO QPF.

COLDER AIR WILL BE DAMMING UP ALONG THE CANADIAN ROCKIES LATER
FRIDAY AND FRIDAY NIGHT. FRASER OUTFLOW IS EXPECTED TO DEVELOP AND
COLDER AIR ALOFT WILL ALSO START TO FILTER INTO THE AREA. SOME
MODELS SHOW RESIDUAL MOISTURE IN PLACE...LOW LEVEL CONVERGENCE...AND
COLDER AIR FILTERING IN. WILL NEED TO WATCH THIS SITUATION CLOSELY
AS THIS SET UP CAN SOMETIMES RESULT IN LOCALIZED LOWLAND SNOW. WILL
REVIEW THIS POTENTIAL FOR THE MORNING FORECAST ISSUANCE.

.LONG TERM...FROM PREVIOUS DISCUSSION...BASED ON AGREEMENT BETWEEN
THE 12Z GFS AND 12Z ECMWF SATURDAY AND SUNDAY WERE CLEARED OUT AND
THE MENTION OF RAIN DROPPED...EXCEPT FOR THE S PART LATE SUNDAY.
WITH COOL DRY N FLOW ALOFT OVER THE AREA AND COLD DRY NE FLOW FROM
THE FRASER VALLEY...SKIES WILL BE MOSTLY SUNNY...TEMPERATURES
COOL...AND N-NE WINDS BREEZY. LOWS WILL DROP INTO THE 20S SATURDAY
NIGHT WITH HIGHS SATURDAY AND SUNDAY IN THE UPPER 30S TO MID 40S.
HOWEVER...CONFIDENCE IN THE MODELS IS STILL RATHER LOW...AND THE 18Z
GFS HAS JUST REVERSED COURSE AND BRINGS RAIN UP FROM OREGON ON
SUNDAY. THE ECMWF HAS BEEN MORE CONSISTENT SO REMAINS THE PREFERRED
SOLUTION. THE ECMWF BRINGS MOISTURE AND RAIN NORTHWARD FROM OREGON
SUNDAY NIGHT.  WITH COLD AIR IN PLACE OVER W WA THERE MAY BE A
CHANCE OF SOME LIGHT SNOW...PARTICULARLY OVER THE NORTHERN ZONES AS
THE PRECIP MOVES NORTH. SO FAR THIS IS NOT ACCOUNTED FOR IN THE
FORECASTS AND WILL HAVE TO BE RE-EVALUATED ONCE MODEL CONSISTENCY
AND AGREEMENT IMPROVES. KAM

&&

.HYDROLOGY...THE AREA OF HEAVIEST RAIN IN THE CASCADES EXTENDED FROM
THE SNOQUALMIE BASIN TO THE NORTH CASCADES THIS EVENING...AND IT
CONTINUES TO SHIFT SLOWLY NORTHWARD. THE HEAVIEST RAIN FOR THE EVENT
SO FAR HAS OCCURRED IN THE MOUNT RAINIER AREA...WHERE LOCALLY UP TO
7 INCHES HAS FALLEN SINCE MONDAY AFTERNOON. THE COWLITZ... NISQUALLY
AND CARBON RIVERS ALL FLOODED. THAT AREA WILL ONLY RECEIVE ANOTHER
INCH OR SO OF RAIN TONIGHT AND WEDNESDAY. THE NISQUALLY AND CARBON
RIVERS HAVE RECEDED BELOW FLOOD STAGE...AND THE COWLITZ AT RANDLE
WILL CREST LATE THIS EVENING.

UP TO 5 INCHES OF RAIN HAS FALLEN OVER THE BASINS OF THE CENTRAL AND
NORTH CASCADES...BUT SO FAR ONLY THE SNOQUALMIE RIVER IS FLOODING.
MORE HEAVY RAIN WILL FALL IN THIS AREA TONIGHT AS THE BAROCLINIC
BAND SHIFTS NORTHWARD...WITH ANOTHER 1 TO 3 INCHES LIKELY AS THE
SNOW LEVEL REMAINS 7000 TO 8000 FT. SO OTHER RIVERS COULD STILL
FLOOD...AND IN FACT THE UPPER REACHES OF THE SNOQUALMIE AND
SKYKOMISH HAVE STARTED RISING AGAIN. IN ADDITION THE ELWHA
RIVER...FLOWING OFF THE NORTH SIDE OF THE OLYMPICS...IS RISING MORE
QUICKLY THAN EXPECTED AND IT WILL NEED WATCHING FOR THE NEXT SEVERAL
HOURS.

THE NEXT FRONTAL SYSTEM WILL BRING ANOTHER ROUND OF HEAVY RAIN
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...RENEWING THE POSSIBILITY OF
FLOODING ON CASCADES RIVERS AND ALSO PERHAPS DRIVING THE SKOKOMISH
RIVER ABOVE FLOOD STAGE. THERE WILL PROBABLY BE 3 TO 6 INCHES OF
RAIN...WITH THE OLYMPICS AND NORTH CASCADES RECEIVING THE HEAVIEST
AMOUNTS. THE SNOW LEVEL WILL BE 5500 TO 7000 FT.   MCDONNAL

&&

.AVIATION...A WARM FRONT JUST NORTH OF PUGET SOUND WILL LIFT TOWARD
THE B.C. BORDER BY WEDNESDAY MORNING. STRONG SW FLOW ALOFT WILL
PERSIST THROUGH WEDNESDAY. STABLE AND MOIST CONDITIONS WILL PERSIST
BUT RAIN WILL BECOME MORE SPOTTY IN NATURE. A FRONT WILL PUSH INTO
WRN WA WEDNESDAY NIGHT.

IFR CEILINGS AND VISIBILITIES HAVE BEEN STUBBORN TO IMPROVE NORTH OF
THE FRONT...BUT AFTER THE FRONT PASSES CEILINGS SHOULD LIFT TO LOW
END MVFR AT LEAST...1-2K FT...AND VISIBILITIES WILL IMPROVE TO 4-6SM
BR. LIGHT WINDS AT THE SURFACE WILL INCREASE TONIGHT BEHIND THE
FRONT.

KSEA...MVFR CONDITIONS LIKELY THROUGH SUNDAY WITH LITTLE RAINFALL
EXPECTED DUE TO SHADOWING OFF THE OLYMPICS. SW WINDS 15-20 KT W/
GUSTS 30 KT...EASING TO 10 KT ON WEDNESDAY.

&&

.MARINE...A FRONT NORTH OF PUGET SOUND WILL MOVE INTO SOUTHERN
BRITISH COLUMBIA BY WEDNESDAY MORNING. SMALL CRAFT ADVISORY STRENGTH
WINDS WILL SPREAD NORTH BEHIND THE FRONT...EXCEPT GALE FORCE WINDS
IN PUGET SOUND.

WINDS WILL INCREASE WEDNESDAY AS A COLD FRONT APPROACHES THE COAST.
AT LEAST SMALL CRAFT ADVISORY LEVEL WINDS ARE LIKELY OVER MOST
WATERS WITH GALES POSSIBLE ON THE COAST AND OVER EXPOSED INLAND
AREAS WEDNESDAY NIGHT. A GALE WATCH IS IN EFFECT FOR THE COAST...THE
STRAIT ENTRANCES...AND THE NORTHERN INLAND WATERS WEDNESDAY NIGHT.

ANOTHER COLD FRONT WILL MOVE THROUGH THE WATERS ON FRIDAY. THIS
FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND MODERATE NORTHERLY WINDS OVER THE OTHER WATERS
LATER FRIDAY INTO SATURDAY. CHB/MERCER

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...VARIOUS FLOOD WATCHES AND WARNINGS IN EFFECT FOR PORTIONS OF
     WESTERN WASHINGTON.
PZ...GALE WARNING FOR PUGET SOUND THROUGH 6 AM WEDNESDAY MORNING.
     SMALL CRAFT ADVISORY ALL WATERS EXCEPT EAST ENTRANCE AND PUGET
     SOUND.
     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.
     GALE WATCH COAST...ENTRANCES...AND NORTHERN INLAND WATERS
     WEDNESDAY NIGHT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
















000
FXUS66 KSEW 260014
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
414 PM PST TUE NOV 25 2014

.SYNOPSIS...A WARM FRONT WILL REMAIN NEAR THE CANADIAN BORDER
TONIGHT AND WEDNESDAY WITH RAIN AT TIMES OVER THE NORTH PART AND
RAIN LIKELY ELSEWHERE TONIGHT. RAIN WILL DIMINISH WITH JUST A CHANCE
OF RAIN ON WEDNESDAY. A FRONT WILL MOVE ACROSS THE AREA WEDNESDAY
NIGHT FOR MORE RAIN AND WINDY CONDITIONS. RAIN WILL CONTINUE ON
THANKSGIVING DAY AS ANOTHER COLD FRONT APPROACHES FROM THE NORTH
THEN CROSSES THE AREA THURSDAY NIGHT. COOL DRY AND BREEZY WEATHER
WILL DEVELOP BY FRIDAY AFTERNOON AND CONTINUE THROUGH THE WEEKEND AS
HIGH PRESSURE BUILDS OVER BRITISH COLUMBIA. WEAK WEATHER SYSTEMS MAY
BRING A LITTLE RAIN EARLY NEXT WEEK.

&&

.SHORT TERM...THE WARM FRONT OVER W WA LOOKS LIKE IT HAS FINALLY
MOVED UP NEAR THE CANADIAN BORDER THIS AFTERNOON. RADAR SHOWS RAIN
IS CONCENTRATED UP OVER WHATCOM COUNTY AND THE N CASCADES. HOWEVER W
FLOW IS STILL BRINGING SOME OROGRAPHIC RAIN TO THE REST OF THE W
SLOPES OF THE CASCADES. THE WARM FRONT IS EXPECTED TO REMAIN NEAR
THE BORDER TONIGHT BRINGING RAIN TO THE FAR NORTHERN LOWLANDS AND
MODERATE TO LOCALLY HEAVY RAIN TO THE N CASCADES. A LITTLE LIGHT
RAIN IS LIKELY OVER THE REST OF THE W WA LOWLANDS TONIGHT WITH
BREEZY S WINDS.

WEDNESDAY STILL LOOKS LIKE A LULL DAY WITH A WEAKER WARM FRONT STILL
UP OVER SOUTHERN B.C. AND THE NEXT FRONT STILL OFFSHORE. IR IMAGERY
SHOWS THIS OFFSHORE FRONT ALONG 140W NEAR THE MAIN LOW NEAR
40N/148W. MODELS REMAIN CONSISTENT IN BRINGING THIS FRONT ACROSS W
WA WEDNESDAY NIGHT. BESIDES ANOTHER INCREASE IN RAIN...THE STRONG SW
LOW LEVEL FLOW AHEAD OF AND BEHIND THE FRONT WILL BRING ANOTHER
ROUND OF HEAVY RAIN TO THE OLYMPICS AND N CASCADES. 3-5 INCHES OF
RAIN IS POSSIBLE OVER THESE AREAS FROM WEDNESDAY NIGHT THROUGH
THURSDAY EVENING...OR 00Z THURSDAY THROUGH 06Z FRIDAY. THIS MEANS
RAIN AT TIMES AND WINDY CONDITIONS OVER THE LOWLANDS FOR
THANKSGIVING DAY...AND POTENTIALLY MORE RIVER FLOODING FOR N
CASCADES RIVERS AND POSSIBLY SOME OLYMPIC RIVERS.

THE OLD WARM FRONT OVER SOUTHERN B.C. WILL MOVE BACK SOUTH AS A COLD
FRONT THURSDAY NIGHT...BEING PUSHED ALONG BY SHORTWAVE TROUGH
EMBEDDED IN N FLOW ALOFT OVER AK AND NORTHERN B.C.  THE UPPER LEVEL
TROUGH WILL PUSH THE COLD FRONT FROM N TO S ACROSS W WA ON
FRIDAY...WITH RAIN ENDING AND CLEARING FROM THE N. COLD NE FRASER
RIVER OUTFLOW WILL DEVELOP BEHIND THE COLD FRONT FRIDAY AFTERNOON
AND NIGHT BRINGING A COLD DRY AIR MASS AND BREEZY WINDS TO W WA.
FRIDAY NIGHT LOWS WILL DROP INTO THE 30S. KAM

.LONG TERM...BASED ON AGREEMENT BETWEEN THE 12Z GFS AND 12Z ECMWF
SATURDAY AND SUNDAY WERE CLEARED OUT AND THE MENTION OF RAIN
DROPPED...EXCEPT FOR THE S PART LATE SUNDAY. WITH COOL DRY N FLOW
ALOFT OVER THE AREA AND COLD DRY NE FLOW FROM THE FRASER
VALLEY...SKIES WILL BE MOSTLY SUNNY...TEMPERATURES COOL...AND N-NE
WINDS BREEZY. LOWS WILL DROP INTO THE 20S SATURDAY NIGHT WITH HIGHS
SATURDAY AND SUNDAY IN THE UPPER 30S TO MID 40S.
HOWEVER...CONFIDENCE IN THE MODELS IS STILL RATHER LOW...AND THE 18Z
GFS HAS JUST REVERSED COURSE AND BRINGS RAIN UP FROM OREGON ON
SUNDAY. THE ECMWF HAS BEEN MORE CONSISTENT SO REMAINS THE PREFERRED
SOLUTION. THE ECMWF BRINGS MOISTURE AND RAIN NORTHWARD FROM OREGON
SUNDAY NIGHT.  WITH COLD AIR IN PLACE OVER W WA THERE MAY BE A
CHANCE OF SOME LIGHT SNOW...PARTICULARLY OVER THE NORTHERN ZONES AS
THE PRECIP MOVES NORTH. SO FAR THIS IS NOT ACCOUNTED FOR IN THE
FORECASTS AND WILL HAVE TO BE RE-EVALUATED ONCE MODEL CONSISTENCY
AND AGREEMENT IMPROVES. KAM

&&

.HYDROLOGY...HEAVY RAIN OVER THE CENTRAL CASCADES WILL RESULT IN
FLOODING ON SEVERAL RIVERS. IN PARTICULAR THE PUYALLUP AT ORTING HAS
REACHED MAJOR FLOOD STAGE. WITH THE WARM FRONT SHIFTING NORTH TO
NEAR CANADIAN BORDER TONIGHT RAIN OVER THE CENTRAL CASCADES HAS
DIMINISHED.

THE WARM FRONT WILL BRING 1 TO 1.5 INCHES OF RAIN TO THE N CASCADES
TONIGHT BEFORE WEAKENING A BIT MORE AND SHIFTING A LITTLE FARTHER
NORTH OVER SOUTHERN B.C.  WEDNESDAY WILL BE A LULL DAY WITH RAIN
CONTINUING OVER THE N CASCADES...BUT NOT HEAVY. SNOW LEVELS WILL
REMAIN HIGH...6000-7000 FEET TONIGHT AND WEDNESDAY.

A FRONT APPROACHING FROM THE WEST WILL BRING MORE HEAVY RAIN
WEDNESDAY NIGHT THROUGH THURSDAY EVENING. STRONG SW LOW LEVEL
FLOW...45-55 KT...WILL IMPACT THE OLYMPICS AND N CASCADES FROM
SNOQUALMIE PASS NORTHWARD. 3-5 INCHES OF RAIN IS POSSIBLE DURING
THIS PERIOD WHICH MAY DRIVE SOME OF THE NORTHERN CASCADES RIVERS TO
FLOOD STAGE ON THURSDAY...INCLUDING THE NOOKSACK...SKAGIT...
STILLAGUAMISH AND SNOQUALMIE/SNOHOMISH BASINS. A FLOOD WATCH WILL
REMAIN IN EFFECT FOR THIS. RIVERS FLOWING OFF THE OLYMPICS MAY ALSO
REACH FLOOD STAGE...MOST NOTABLY THE SKOKOMISH AND POSSIBLY THE
BOGACHIEL. SNOW LEVELS WILL BE A LITTLE LOWER...IN THE 5500 TO 6500
FOOT RANGE.

THE RAIN WILL END LATE THURSDAY NIGHT AND FRIDAY AS A COLD FRONT
SWEEPS SOUTH ACROSS THE AREA. KAM

&&

.AVIATION...MODERATE WESTERLY FLOW ALOFT AS A FRONT OVER THE CENTRAL
PUGET SOUND AREA THIS AFTERNOON SLOWLY MOVES NORTH INTO BRITISH
COLUMBIA TONIGHT. IFR CEILINGS AND VISIBILITIES HAVE BEEN STUBBORN
TO IMPROVE NORTH OF THE FRONT TODAY...BUT AFTER THE FRONT PASSES
CEILINGS SHOULD LIFT TO LOW END MVFR AT LEAST...1-2K FT...AND
VISIBILITIES WILL IMPROVE TO 4-6SM BR. LIGHT WINDS AT THE SURFACE
WILL INCREASE TONIGHT BEHIND THE FRONT.

KSEA...CONDITIONS SHOULD IMPROVE FROM THE CURRENT IFR TO LOW END
MVFR AROUND 00Z AS THE SURFACE FRONT MOVES NORTH PAST THE TERMINAL.
LIGHT WINDS WILL BECOME SOUTHERLY 10-14KT BEHIND THE FRONT ABOUT
00Z. CHB

&&

.MARINE...A FRONT OVER CENTRAL PUGET SOUND THIS AFTERNOON WILL MOVE
NORTH INTO SOUTHERN BRITISH COLUMBIA TONIGHT. SMALL CRAFT ADVISORY
STRENGTH WINDS WILL SPREAD NORTH BEHIND THE FRONT.

WINDS WILL INCREASE WEDNESDAY AS A COLD FRONT APPROACHES THE COAST.
AT LEAST SMALL CRAFT ADVISORY LEVEL WINDS ARE LIKELY OVER MOST
WATERS WITH GALES POSSIBLE ON THE COAST AND OVER EXPOSED INLAND
AREAS WEDNESDAY NIGHT. A GALE WATCH IS IN EFFECT FOR THE COAST...THE
STRAIT ENTRANCES...AND THE NORTHERN INLAND WATERS WEDNESDAY NIGHT.

ANOTHER COLD FRONT WILL MOVE THROUGH THE WATERS ON FRIDAY. THIS
FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND MODERATE NORTHERLY WINDS OVER THE OTHER WATERS
LATER FRIDAY INTO SATURDAY. CHB

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCH IN EFFECT FOR PORTIONS OF THE AREA.
PZ...SMALL CRAFT ADVISORY ALL WATERS EXCEPT EAST ENTRANCE.
     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.
     GALE WATCH COAST...ENTRANCES...AND NORTHERN INLAND WATERS
     WEDNESDAY NIGHT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML














000
FXUS66 KSEW 260014
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
414 PM PST TUE NOV 25 2014

.SYNOPSIS...A WARM FRONT WILL REMAIN NEAR THE CANADIAN BORDER
TONIGHT AND WEDNESDAY WITH RAIN AT TIMES OVER THE NORTH PART AND
RAIN LIKELY ELSEWHERE TONIGHT. RAIN WILL DIMINISH WITH JUST A CHANCE
OF RAIN ON WEDNESDAY. A FRONT WILL MOVE ACROSS THE AREA WEDNESDAY
NIGHT FOR MORE RAIN AND WINDY CONDITIONS. RAIN WILL CONTINUE ON
THANKSGIVING DAY AS ANOTHER COLD FRONT APPROACHES FROM THE NORTH
THEN CROSSES THE AREA THURSDAY NIGHT. COOL DRY AND BREEZY WEATHER
WILL DEVELOP BY FRIDAY AFTERNOON AND CONTINUE THROUGH THE WEEKEND AS
HIGH PRESSURE BUILDS OVER BRITISH COLUMBIA. WEAK WEATHER SYSTEMS MAY
BRING A LITTLE RAIN EARLY NEXT WEEK.

&&

.SHORT TERM...THE WARM FRONT OVER W WA LOOKS LIKE IT HAS FINALLY
MOVED UP NEAR THE CANADIAN BORDER THIS AFTERNOON. RADAR SHOWS RAIN
IS CONCENTRATED UP OVER WHATCOM COUNTY AND THE N CASCADES. HOWEVER W
FLOW IS STILL BRINGING SOME OROGRAPHIC RAIN TO THE REST OF THE W
SLOPES OF THE CASCADES. THE WARM FRONT IS EXPECTED TO REMAIN NEAR
THE BORDER TONIGHT BRINGING RAIN TO THE FAR NORTHERN LOWLANDS AND
MODERATE TO LOCALLY HEAVY RAIN TO THE N CASCADES. A LITTLE LIGHT
RAIN IS LIKELY OVER THE REST OF THE W WA LOWLANDS TONIGHT WITH
BREEZY S WINDS.

WEDNESDAY STILL LOOKS LIKE A LULL DAY WITH A WEAKER WARM FRONT STILL
UP OVER SOUTHERN B.C. AND THE NEXT FRONT STILL OFFSHORE. IR IMAGERY
SHOWS THIS OFFSHORE FRONT ALONG 140W NEAR THE MAIN LOW NEAR
40N/148W. MODELS REMAIN CONSISTENT IN BRINGING THIS FRONT ACROSS W
WA WEDNESDAY NIGHT. BESIDES ANOTHER INCREASE IN RAIN...THE STRONG SW
LOW LEVEL FLOW AHEAD OF AND BEHIND THE FRONT WILL BRING ANOTHER
ROUND OF HEAVY RAIN TO THE OLYMPICS AND N CASCADES. 3-5 INCHES OF
RAIN IS POSSIBLE OVER THESE AREAS FROM WEDNESDAY NIGHT THROUGH
THURSDAY EVENING...OR 00Z THURSDAY THROUGH 06Z FRIDAY. THIS MEANS
RAIN AT TIMES AND WINDY CONDITIONS OVER THE LOWLANDS FOR
THANKSGIVING DAY...AND POTENTIALLY MORE RIVER FLOODING FOR N
CASCADES RIVERS AND POSSIBLY SOME OLYMPIC RIVERS.

THE OLD WARM FRONT OVER SOUTHERN B.C. WILL MOVE BACK SOUTH AS A COLD
FRONT THURSDAY NIGHT...BEING PUSHED ALONG BY SHORTWAVE TROUGH
EMBEDDED IN N FLOW ALOFT OVER AK AND NORTHERN B.C.  THE UPPER LEVEL
TROUGH WILL PUSH THE COLD FRONT FROM N TO S ACROSS W WA ON
FRIDAY...WITH RAIN ENDING AND CLEARING FROM THE N. COLD NE FRASER
RIVER OUTFLOW WILL DEVELOP BEHIND THE COLD FRONT FRIDAY AFTERNOON
AND NIGHT BRINGING A COLD DRY AIR MASS AND BREEZY WINDS TO W WA.
FRIDAY NIGHT LOWS WILL DROP INTO THE 30S. KAM

.LONG TERM...BASED ON AGREEMENT BETWEEN THE 12Z GFS AND 12Z ECMWF
SATURDAY AND SUNDAY WERE CLEARED OUT AND THE MENTION OF RAIN
DROPPED...EXCEPT FOR THE S PART LATE SUNDAY. WITH COOL DRY N FLOW
ALOFT OVER THE AREA AND COLD DRY NE FLOW FROM THE FRASER
VALLEY...SKIES WILL BE MOSTLY SUNNY...TEMPERATURES COOL...AND N-NE
WINDS BREEZY. LOWS WILL DROP INTO THE 20S SATURDAY NIGHT WITH HIGHS
SATURDAY AND SUNDAY IN THE UPPER 30S TO MID 40S.
HOWEVER...CONFIDENCE IN THE MODELS IS STILL RATHER LOW...AND THE 18Z
GFS HAS JUST REVERSED COURSE AND BRINGS RAIN UP FROM OREGON ON
SUNDAY. THE ECMWF HAS BEEN MORE CONSISTENT SO REMAINS THE PREFERRED
SOLUTION. THE ECMWF BRINGS MOISTURE AND RAIN NORTHWARD FROM OREGON
SUNDAY NIGHT.  WITH COLD AIR IN PLACE OVER W WA THERE MAY BE A
CHANCE OF SOME LIGHT SNOW...PARTICULARLY OVER THE NORTHERN ZONES AS
THE PRECIP MOVES NORTH. SO FAR THIS IS NOT ACCOUNTED FOR IN THE
FORECASTS AND WILL HAVE TO BE RE-EVALUATED ONCE MODEL CONSISTENCY
AND AGREEMENT IMPROVES. KAM

&&

.HYDROLOGY...HEAVY RAIN OVER THE CENTRAL CASCADES WILL RESULT IN
FLOODING ON SEVERAL RIVERS. IN PARTICULAR THE PUYALLUP AT ORTING HAS
REACHED MAJOR FLOOD STAGE. WITH THE WARM FRONT SHIFTING NORTH TO
NEAR CANADIAN BORDER TONIGHT RAIN OVER THE CENTRAL CASCADES HAS
DIMINISHED.

THE WARM FRONT WILL BRING 1 TO 1.5 INCHES OF RAIN TO THE N CASCADES
TONIGHT BEFORE WEAKENING A BIT MORE AND SHIFTING A LITTLE FARTHER
NORTH OVER SOUTHERN B.C.  WEDNESDAY WILL BE A LULL DAY WITH RAIN
CONTINUING OVER THE N CASCADES...BUT NOT HEAVY. SNOW LEVELS WILL
REMAIN HIGH...6000-7000 FEET TONIGHT AND WEDNESDAY.

A FRONT APPROACHING FROM THE WEST WILL BRING MORE HEAVY RAIN
WEDNESDAY NIGHT THROUGH THURSDAY EVENING. STRONG SW LOW LEVEL
FLOW...45-55 KT...WILL IMPACT THE OLYMPICS AND N CASCADES FROM
SNOQUALMIE PASS NORTHWARD. 3-5 INCHES OF RAIN IS POSSIBLE DURING
THIS PERIOD WHICH MAY DRIVE SOME OF THE NORTHERN CASCADES RIVERS TO
FLOOD STAGE ON THURSDAY...INCLUDING THE NOOKSACK...SKAGIT...
STILLAGUAMISH AND SNOQUALMIE/SNOHOMISH BASINS. A FLOOD WATCH WILL
REMAIN IN EFFECT FOR THIS. RIVERS FLOWING OFF THE OLYMPICS MAY ALSO
REACH FLOOD STAGE...MOST NOTABLY THE SKOKOMISH AND POSSIBLY THE
BOGACHIEL. SNOW LEVELS WILL BE A LITTLE LOWER...IN THE 5500 TO 6500
FOOT RANGE.

THE RAIN WILL END LATE THURSDAY NIGHT AND FRIDAY AS A COLD FRONT
SWEEPS SOUTH ACROSS THE AREA. KAM

&&

.AVIATION...MODERATE WESTERLY FLOW ALOFT AS A FRONT OVER THE CENTRAL
PUGET SOUND AREA THIS AFTERNOON SLOWLY MOVES NORTH INTO BRITISH
COLUMBIA TONIGHT. IFR CEILINGS AND VISIBILITIES HAVE BEEN STUBBORN
TO IMPROVE NORTH OF THE FRONT TODAY...BUT AFTER THE FRONT PASSES
CEILINGS SHOULD LIFT TO LOW END MVFR AT LEAST...1-2K FT...AND
VISIBILITIES WILL IMPROVE TO 4-6SM BR. LIGHT WINDS AT THE SURFACE
WILL INCREASE TONIGHT BEHIND THE FRONT.

KSEA...CONDITIONS SHOULD IMPROVE FROM THE CURRENT IFR TO LOW END
MVFR AROUND 00Z AS THE SURFACE FRONT MOVES NORTH PAST THE TERMINAL.
LIGHT WINDS WILL BECOME SOUTHERLY 10-14KT BEHIND THE FRONT ABOUT
00Z. CHB

&&

.MARINE...A FRONT OVER CENTRAL PUGET SOUND THIS AFTERNOON WILL MOVE
NORTH INTO SOUTHERN BRITISH COLUMBIA TONIGHT. SMALL CRAFT ADVISORY
STRENGTH WINDS WILL SPREAD NORTH BEHIND THE FRONT.

WINDS WILL INCREASE WEDNESDAY AS A COLD FRONT APPROACHES THE COAST.
AT LEAST SMALL CRAFT ADVISORY LEVEL WINDS ARE LIKELY OVER MOST
WATERS WITH GALES POSSIBLE ON THE COAST AND OVER EXPOSED INLAND
AREAS WEDNESDAY NIGHT. A GALE WATCH IS IN EFFECT FOR THE COAST...THE
STRAIT ENTRANCES...AND THE NORTHERN INLAND WATERS WEDNESDAY NIGHT.

ANOTHER COLD FRONT WILL MOVE THROUGH THE WATERS ON FRIDAY. THIS
FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND MODERATE NORTHERLY WINDS OVER THE OTHER WATERS
LATER FRIDAY INTO SATURDAY. CHB

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCH IN EFFECT FOR PORTIONS OF THE AREA.
PZ...SMALL CRAFT ADVISORY ALL WATERS EXCEPT EAST ENTRANCE.
     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.
     GALE WATCH COAST...ENTRANCES...AND NORTHERN INLAND WATERS
     WEDNESDAY NIGHT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML













000
FXUS66 KSEW 251740
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
940 AM PST TUE NOV 25 2014

.SYNOPSIS...A WARM FRONT WILL BRING RAINY BREEZY WEATHER TO WESTERN
WASHINGTON TODAY...WITH HEAVY RAIN IN THE MOUNTAINS. AFTER A
RELATIVE LULL TONIGHT AND WEDNESDAY...ANOTHER FRONT WILL BRING MORE
RAINY WINDY WEATHER WEDNESDAY NIGHT AND THANKSGIVING. RAIN WILL
DECREASE ON FRIDAY AS A COLD FRONT MOVES SOUTHEAST ACROSS THE AREA.
COOLER DRIER WEATHER IS EXPECTED FOR THIS WEEKEND.

&&

.SHORT TERM...A WARM FRONT IS DRAPED OVER W WA THIS MORNING. LIGHT
RAIN AT TIMES IS EXPECTED OVER THE LOWLANDS WITH LOCALIZED HEAVY
RAIN OVER THE CASCADES. SO FAR A STRONG LOW LEVEL WESTERLY JET
PASSING S OF THE OLYMPICS HAS BEEN SLAMMING INTO THE CASCADES S OF
SNOQUALMIE PASS...PRODUCING HEAVY RAIN. 24 HOUR PRECIP OVER THE
CASCADES FROM STEVENS PASS SOUTHWARD HAS RANGED FROM 2-5 INCHES WITH
THE 5 INCH BULLSEYES AROUND MT RAINIER.

THE WARM FRONT EXTENDS E FROM A LARGE UPPER LEVEL LOW OFFSHORE NEAR
40N/150W...ACROSS A BROAD FLAT UPPER LEVEL RIDGE CENTERED JUST
OFFSHORE ALONG ROUGHLY 130W. MODELS STILL AGREE ON SHIFTING THE WARM
FRONT NORTH TODAY...EVENTUALLY STALLING IT ALONG THE CANADIAN BORDER
THIS EVENING. HRRR MODEL SHOWS THE HEAVY RAIN OVER THE CENTRAL
DIMINISHING EARLY THIS AFTERNOON AROUND 21Z AS THE WARM FRONT SHIFTS
N. MODELS SEEM TO MOVE THE FRONT QUICK ENOUGH SO THAT MOST OF THE
REST OF THE CASCADES DO NOT GET AS MUCH HEAVY RAIN AS PREVIOUSLY
EXPECTED. HOWEVER THE FRONT IS CLOSE ENOUGH TO THE BORDER SO THAT
HEAVY RAIN COULD CONTINUE OVER FAR N CASCADES TONIGHT.

OVER THE LOWLANDS...RAIN WILL DIMINISH FROM S TO N THIS AFTERNOON AS
THE WARM FRONT MOVES N. RAIN WILL PROBABLY CONTINUE UP AROUND
BELLINGHAM WITH THE WARM FRONT STILL IN THE VICINITY.

A COLD FRONT ORIGINATING FROM THE OFFSHORE LOW IS STILL FORECAST TO
MOVE ACROSS W WA WEDNESDAY NIGHT. SW FLOW ALOFT WILL INCREASE AHEAD
OF THE FRONT AND CONTINUE BEHIND IT INTO THURSDAY NIGHT...UNTIL THE
LAST COLD FRONT MOVING S DOWN THE B.C. COAST FINALLY CROSSES THE
AREA FRIDAY MORNING. THE STRONG SW FLOW ALOFT WILL PRODUCE MORE
HEAVY RAIN OVER THE N CASCADES AND OVER THE OLYMPICS. THE LOWLANDS
WILL GET RAIN...BUT PARTS OF THE PUGET SOUND REGION WILL BE SHADOWED
BY THE OLYMPICS AT TIMES.

ALL THE WARM ADVECTION THE NEXT COUPLE OF DAYS WILL KEEP
TEMPERATURES MILD WITH LOWS NEAR 50 AND HIGHS IN THE MID 50S. WINDS
WILL BE BREEZY AT TIMES...PARTICULARLY ALONG THE COAST AND OVER THE
N INTERIOR. KAM

.LONG TERM...PREVIOUS DISCUSSION FROM THE 3 AM AFD...PRECIPITATION
OVER WESTERN WASHINGTON SHOULD DECREASE ON FRIDAY...IN THE WAKE OF
THE FRONT THAT DIGS THROUGH THE AREA THURSDAY NIGHT. MODELS HAVE
COME INTO FAIRLY STRONG AGREEMENT THAT AN UPPER TROUGH WILL DIG INTO
THE AREA FROM THE NORTHWEST FRIDAY NIGHT AND SATURDAY...WHILE
SURFACE HIGH PRESSURE OVER SOUTHERN BRITISH COLUMBIA PRODUCES
NORTHEAST PRESSURE GRADIENTS. THE WEEKEND WILL BE QUITE COOL WITH
LOWS IN THE MID 20S TO LOWER 30S AND HIGHS IN THE MID 30S TO MID
40S. THE DAYS SHOULD BE AT LEAST PARTLY SUNNY. WE WILL KEEP A
LOW-END CHANCE OF A SHOWER IN THE FORECAST FOR NOW...BUT ANY
PRECIPITATION WOULD BE VERY LIGHT. IT LOOKS LIKE THE COOL DRY SPELL
WILL BE SHORT LIVED...WITH ANOTHER FRONTAL SYSTEM LIFTING INTO
WESTERN WASHINGTON FROM THE SOUTHWEST SUNDAY NIGHT OR MONDAY.
MCDONNAL

&&

.HYDROLOGY...STRONG LOW LEVEL W FLOW ALOFT HAS DROPPED 2 TO 5 INCHES
OF RAIN OVER THE CENTRAL CASCADES FROM ABOUT STEVENS PASS
SOUTHWARD...WITH THE HEAVIEST AMOUNTS OVER THE MT RAINIER AREA.
SEVERAL FLOOD WARNING HAVE ALREADY BEEN ISSUED...AND A FLOOD WATCH
CONTINUES FOR THE CASCADES...INCLUDING THE COWLITZ...PUYALLUP NEAR
ORTING...SNOQUALMIE... TOLT...SKYKOMISH...SNOHOMISH...
STILLAGUAMISH...AND NOOKSACK RIVERS.


THE HEAVY RAIN WILL CONTINUE THROUGH EARLY THIS AFTERNOON
PARTICULARLY OVER THE MT RAINIER AREA. RAIN WILL DIMINISH THERE AS
THE WARM FRONT OVER THE AREA SHIFTS N...REACHING THE CANADIAN BORDER
EARLY THIS EVENING. MODELS APPEAR TO MOVE THE FRONT FAST ENOUGH SO
THAT ONLY MODERATE RAIN WILL FALL OVER THE NORTH CASCADES TODAY.

THE WARM FRONT WILL STALL ALONG THE CANADIAN BORDER TONIGHT WHICH
COULD ALLOW MODERATE RAIN TO CONTINUE OVER THE N CASCADES IN WHATCOM
AND SKAGIT COUNTY TONIGHT...WITH ANOTHER 0.75-1.50 INCHES POSSIBLE
FROM 03Z-15Z. SNOW LEVELS WILL REMAIN HIGH...FROM ROUGHLY 6000 TO
8000 FEET TONIGHT AND WEDNESDAY...LOWERING TO 5000-6000 FEET
THURSDAY AFTERNOON.

THERE WILL BE MORE OF A LULL IN RAIN ON WEDNESDAY AHEAD OF AN
APPROACHING COLD FRONT. STRONG LOW LEVEL SW FLOW ALOFT WILL DEVELOP
WEDNESDAY EVENING AHEAD OF THE COLD FRONT AND CONTINUE BEHIND THE
FRONT THROUGH THURSDAY AFTERNOON OR EVENING. THE SW DIRECTION SHOULD
PUT THE HEAVIEST RAIN OVER THE OLYMPICS AND N CASCADES WITH ANOTHER
3 TO 5 INCHES POSSIBLE IN THOSE AREAS. KAM

&&

.AVIATION...MODERATE WESTERLY FLOW ALOFT. A FRONT OVER THE AREA WILL
GIVE LOW MVFR TO IFR CEILINGS AND VISIBILITIES IN RAIN TO MOST
TERMINALS TODAY. THE FRONT WILL MOVE NORTH LATE THIS AFTERNOON AND
WILL REACH THE CANADIAN BORDER TONIGHT. LIGHT WINDS AT THE SURFACE
WILL INCREASE TONIGHT BEHIND THE FRONT. SLIGHT IMPROVEMENT TO
VISIBILITIES AND CEILINGS CAN BE EXPECTED BEHIND THE FRONT.

KSEA...CEILINGS AROUND 005 WITH VISIBILITY 3-5SM IN -RA BR. THE
FRONT WILL MOVE NORTH ABOUT 00Z THIS AFTERNOON WITH VISIBILITY
RISING TO P6SM AND CIGS RISING TO 008-012. LIGHT WINDS WILL BECOME
SOUTHERLY 10-14KT BEHIND THE FRONT ABOUT 00Z. CHB

&&

.MARINE...A FRONT OVER THE AREA THIS MORNING WILL MOVE NORTH INTO
SOUTHERN BRITISH COLUMBIA LATE THIS AFTERNOON AND EVENING. SMALL
CRAFT ADVISORY WINDS ARE LIKELY ON THE COAST LATER TODAY AND
TONIGHT. WINDS WILL BE GENERALLY LIGHTER INLAND.

WINDS WILL INCREASE WEDNESDAY AS A COLD FRONT APPROACHES THE COAST.
AT LEAST SMALL CRAFT ADVISORY LEVEL WINDS ARE LIKELY OVER MOST
WATERS WITH GALES POSSIBLE ON THE COAST AND OVER EXPOSED INLAND
AREAS WEDNESDAY NIGHT. A GALE WATCH IS IN EFFECT FOR THE COAST...THE
STRAIT ENTRANCES...AND THE NORTHERN INLAND WATERS WEDNESDAY NIGHT.

ANOTHER COLD FRONT WILL MOVE THROUGH THE WATERS ON FRIDAY. THIS
FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND MODERATE NORTHERLY WINDS OVER THE OTHER WATERS
LATER FRIDAY INTO SATURDAY. CHB

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCH IN EFFECT FOR PORTIONS OF THE AREA.
PZ...SMALL CRAFT ADVISORY COAST AND WEST ENTRANCE.
     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.
     GALE WATCH COAST...ENTRANCES...AND NORTHERN INLAND WATERS
     WEDNESDAY NIGHT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML











000
FXUS66 KSEW 251740
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
940 AM PST TUE NOV 25 2014

.SYNOPSIS...A WARM FRONT WILL BRING RAINY BREEZY WEATHER TO WESTERN
WASHINGTON TODAY...WITH HEAVY RAIN IN THE MOUNTAINS. AFTER A
RELATIVE LULL TONIGHT AND WEDNESDAY...ANOTHER FRONT WILL BRING MORE
RAINY WINDY WEATHER WEDNESDAY NIGHT AND THANKSGIVING. RAIN WILL
DECREASE ON FRIDAY AS A COLD FRONT MOVES SOUTHEAST ACROSS THE AREA.
COOLER DRIER WEATHER IS EXPECTED FOR THIS WEEKEND.

&&

.SHORT TERM...A WARM FRONT IS DRAPED OVER W WA THIS MORNING. LIGHT
RAIN AT TIMES IS EXPECTED OVER THE LOWLANDS WITH LOCALIZED HEAVY
RAIN OVER THE CASCADES. SO FAR A STRONG LOW LEVEL WESTERLY JET
PASSING S OF THE OLYMPICS HAS BEEN SLAMMING INTO THE CASCADES S OF
SNOQUALMIE PASS...PRODUCING HEAVY RAIN. 24 HOUR PRECIP OVER THE
CASCADES FROM STEVENS PASS SOUTHWARD HAS RANGED FROM 2-5 INCHES WITH
THE 5 INCH BULLSEYES AROUND MT RAINIER.

THE WARM FRONT EXTENDS E FROM A LARGE UPPER LEVEL LOW OFFSHORE NEAR
40N/150W...ACROSS A BROAD FLAT UPPER LEVEL RIDGE CENTERED JUST
OFFSHORE ALONG ROUGHLY 130W. MODELS STILL AGREE ON SHIFTING THE WARM
FRONT NORTH TODAY...EVENTUALLY STALLING IT ALONG THE CANADIAN BORDER
THIS EVENING. HRRR MODEL SHOWS THE HEAVY RAIN OVER THE CENTRAL
DIMINISHING EARLY THIS AFTERNOON AROUND 21Z AS THE WARM FRONT SHIFTS
N. MODELS SEEM TO MOVE THE FRONT QUICK ENOUGH SO THAT MOST OF THE
REST OF THE CASCADES DO NOT GET AS MUCH HEAVY RAIN AS PREVIOUSLY
EXPECTED. HOWEVER THE FRONT IS CLOSE ENOUGH TO THE BORDER SO THAT
HEAVY RAIN COULD CONTINUE OVER FAR N CASCADES TONIGHT.

OVER THE LOWLANDS...RAIN WILL DIMINISH FROM S TO N THIS AFTERNOON AS
THE WARM FRONT MOVES N. RAIN WILL PROBABLY CONTINUE UP AROUND
BELLINGHAM WITH THE WARM FRONT STILL IN THE VICINITY.

A COLD FRONT ORIGINATING FROM THE OFFSHORE LOW IS STILL FORECAST TO
MOVE ACROSS W WA WEDNESDAY NIGHT. SW FLOW ALOFT WILL INCREASE AHEAD
OF THE FRONT AND CONTINUE BEHIND IT INTO THURSDAY NIGHT...UNTIL THE
LAST COLD FRONT MOVING S DOWN THE B.C. COAST FINALLY CROSSES THE
AREA FRIDAY MORNING. THE STRONG SW FLOW ALOFT WILL PRODUCE MORE
HEAVY RAIN OVER THE N CASCADES AND OVER THE OLYMPICS. THE LOWLANDS
WILL GET RAIN...BUT PARTS OF THE PUGET SOUND REGION WILL BE SHADOWED
BY THE OLYMPICS AT TIMES.

ALL THE WARM ADVECTION THE NEXT COUPLE OF DAYS WILL KEEP
TEMPERATURES MILD WITH LOWS NEAR 50 AND HIGHS IN THE MID 50S. WINDS
WILL BE BREEZY AT TIMES...PARTICULARLY ALONG THE COAST AND OVER THE
N INTERIOR. KAM

.LONG TERM...PREVIOUS DISCUSSION FROM THE 3 AM AFD...PRECIPITATION
OVER WESTERN WASHINGTON SHOULD DECREASE ON FRIDAY...IN THE WAKE OF
THE FRONT THAT DIGS THROUGH THE AREA THURSDAY NIGHT. MODELS HAVE
COME INTO FAIRLY STRONG AGREEMENT THAT AN UPPER TROUGH WILL DIG INTO
THE AREA FROM THE NORTHWEST FRIDAY NIGHT AND SATURDAY...WHILE
SURFACE HIGH PRESSURE OVER SOUTHERN BRITISH COLUMBIA PRODUCES
NORTHEAST PRESSURE GRADIENTS. THE WEEKEND WILL BE QUITE COOL WITH
LOWS IN THE MID 20S TO LOWER 30S AND HIGHS IN THE MID 30S TO MID
40S. THE DAYS SHOULD BE AT LEAST PARTLY SUNNY. WE WILL KEEP A
LOW-END CHANCE OF A SHOWER IN THE FORECAST FOR NOW...BUT ANY
PRECIPITATION WOULD BE VERY LIGHT. IT LOOKS LIKE THE COOL DRY SPELL
WILL BE SHORT LIVED...WITH ANOTHER FRONTAL SYSTEM LIFTING INTO
WESTERN WASHINGTON FROM THE SOUTHWEST SUNDAY NIGHT OR MONDAY.
MCDONNAL

&&

.HYDROLOGY...STRONG LOW LEVEL W FLOW ALOFT HAS DROPPED 2 TO 5 INCHES
OF RAIN OVER THE CENTRAL CASCADES FROM ABOUT STEVENS PASS
SOUTHWARD...WITH THE HEAVIEST AMOUNTS OVER THE MT RAINIER AREA.
SEVERAL FLOOD WARNING HAVE ALREADY BEEN ISSUED...AND A FLOOD WATCH
CONTINUES FOR THE CASCADES...INCLUDING THE COWLITZ...PUYALLUP NEAR
ORTING...SNOQUALMIE... TOLT...SKYKOMISH...SNOHOMISH...
STILLAGUAMISH...AND NOOKSACK RIVERS.


THE HEAVY RAIN WILL CONTINUE THROUGH EARLY THIS AFTERNOON
PARTICULARLY OVER THE MT RAINIER AREA. RAIN WILL DIMINISH THERE AS
THE WARM FRONT OVER THE AREA SHIFTS N...REACHING THE CANADIAN BORDER
EARLY THIS EVENING. MODELS APPEAR TO MOVE THE FRONT FAST ENOUGH SO
THAT ONLY MODERATE RAIN WILL FALL OVER THE NORTH CASCADES TODAY.

THE WARM FRONT WILL STALL ALONG THE CANADIAN BORDER TONIGHT WHICH
COULD ALLOW MODERATE RAIN TO CONTINUE OVER THE N CASCADES IN WHATCOM
AND SKAGIT COUNTY TONIGHT...WITH ANOTHER 0.75-1.50 INCHES POSSIBLE
FROM 03Z-15Z. SNOW LEVELS WILL REMAIN HIGH...FROM ROUGHLY 6000 TO
8000 FEET TONIGHT AND WEDNESDAY...LOWERING TO 5000-6000 FEET
THURSDAY AFTERNOON.

THERE WILL BE MORE OF A LULL IN RAIN ON WEDNESDAY AHEAD OF AN
APPROACHING COLD FRONT. STRONG LOW LEVEL SW FLOW ALOFT WILL DEVELOP
WEDNESDAY EVENING AHEAD OF THE COLD FRONT AND CONTINUE BEHIND THE
FRONT THROUGH THURSDAY AFTERNOON OR EVENING. THE SW DIRECTION SHOULD
PUT THE HEAVIEST RAIN OVER THE OLYMPICS AND N CASCADES WITH ANOTHER
3 TO 5 INCHES POSSIBLE IN THOSE AREAS. KAM

&&

.AVIATION...MODERATE WESTERLY FLOW ALOFT. A FRONT OVER THE AREA WILL
GIVE LOW MVFR TO IFR CEILINGS AND VISIBILITIES IN RAIN TO MOST
TERMINALS TODAY. THE FRONT WILL MOVE NORTH LATE THIS AFTERNOON AND
WILL REACH THE CANADIAN BORDER TONIGHT. LIGHT WINDS AT THE SURFACE
WILL INCREASE TONIGHT BEHIND THE FRONT. SLIGHT IMPROVEMENT TO
VISIBILITIES AND CEILINGS CAN BE EXPECTED BEHIND THE FRONT.

KSEA...CEILINGS AROUND 005 WITH VISIBILITY 3-5SM IN -RA BR. THE
FRONT WILL MOVE NORTH ABOUT 00Z THIS AFTERNOON WITH VISIBILITY
RISING TO P6SM AND CIGS RISING TO 008-012. LIGHT WINDS WILL BECOME
SOUTHERLY 10-14KT BEHIND THE FRONT ABOUT 00Z. CHB

&&

.MARINE...A FRONT OVER THE AREA THIS MORNING WILL MOVE NORTH INTO
SOUTHERN BRITISH COLUMBIA LATE THIS AFTERNOON AND EVENING. SMALL
CRAFT ADVISORY WINDS ARE LIKELY ON THE COAST LATER TODAY AND
TONIGHT. WINDS WILL BE GENERALLY LIGHTER INLAND.

WINDS WILL INCREASE WEDNESDAY AS A COLD FRONT APPROACHES THE COAST.
AT LEAST SMALL CRAFT ADVISORY LEVEL WINDS ARE LIKELY OVER MOST
WATERS WITH GALES POSSIBLE ON THE COAST AND OVER EXPOSED INLAND
AREAS WEDNESDAY NIGHT. A GALE WATCH IS IN EFFECT FOR THE COAST...THE
STRAIT ENTRANCES...AND THE NORTHERN INLAND WATERS WEDNESDAY NIGHT.

ANOTHER COLD FRONT WILL MOVE THROUGH THE WATERS ON FRIDAY. THIS
FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND MODERATE NORTHERLY WINDS OVER THE OTHER WATERS
LATER FRIDAY INTO SATURDAY. CHB

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCH IN EFFECT FOR PORTIONS OF THE AREA.
PZ...SMALL CRAFT ADVISORY COAST AND WEST ENTRANCE.
     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.
     GALE WATCH COAST...ENTRANCES...AND NORTHERN INLAND WATERS
     WEDNESDAY NIGHT.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML










000
FXUS66 KSEW 251156
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
300 AM PST TUE NOV 25 2014

.SYNOPSIS...A WARM FRONT WILL BRING RAINY BREEZY WEATHER TO WESTERN
WASHINGTON TODAY AND TONIGHT...WITH HEAVY RAIN IN THE MOUNTAINS.
AFTER A RELATIVE LULL WEDNESDAY...ANOTHER FRONTAL SYSTEM WILL BRING
MORE RAINY WINDY WEATHER WEDNESDAY NIGHT AND THANKSGIVING. RAIN WILL
DECREASE FRIDAY AS THE COLD FRONT MOVES SOUTHEAST...AND COLDER DRIER
WEATHER IS EXPECTED FOR THE WEEKEND.

&&

.SHORT TERM...MOIST WEST-NORTHWEST FLOW CONTINUES ALOFT OVER WESTERN
WASHINGTON...JUST DOWNSTREAM OF THE FLAT UPPER RIDGE CENTERED
OFFSHORE ALONG 130W. THE WARM FRONT MOVING INTO THE AREA OVERNIGHT
RENEWED WIDESPREAD RAINFALL...AND TEMPERATURES ROSE SLIGHTLY INTO
THE UPPER 40S TO LOWER 50S.

A BAROCLINIC BAND CARRYING SUB-TROPICAL MOISTURE OVER THE NORTH SIDE
OF THE OFFSHORE RIDGE WILL CONTINUE TO BRING RAIN TO WESTERN
WASHINGTON TODAY. THE MODELS HAVE COME INTO FAIRLY STRONG AGREEMENT
THAT THE BAND WILL BEGIN LIFTING NORTHWARD TONIGHT AND WEDNESDAY...
AS THE RIDGE OFFSHORE AMPLIFIES AHEAD OF ANOTHER APPROACHING FRONTAL
SYSTEM.

THE WESTERN WASHINGTON LOWLANDS WILL RECEIVE FAIRLY SIGNIFICANT
RAINFALL THIS MORNING -- UP TO 0.75 INCH IN PLACES. FROM THE PUGET
SOUND AREA SOUTHWARD...THE RAIN SHOULD GENERALLY LET UP DURING THE
DAY. RAINFALL AMOUNTS OVER THE LOWLANDS WILL BE LESS TONIGHT AND
LESS YET ON WEDNESDAY...WITH THE PUGET SOUND REGION LARGELY IN THE
RAIN SHADOW OF THE OLYMPICS MUCH OF THE TIME. IT WILL ALSO BE BREEZY
AT TIMES OVER THE LOWLANDS TONIGHT AND WEDNESDAY.

THIS PATTERN FAVORS HEAVY RAIN IN THE CASCADES...AS WE HAVE BEEN
ADVERTISING FOR SEVERAL DAYS. IT WILL BE FOCUSED ON THE WASHINGTON
CASCADES FROM ABOUT SNOQUALMIE PASS SOUTHWARD THIS MORNING...THEN
GRADUALLY SHIFT NORTHWARD THIS AFTERNOON AND TONIGHT. PRECIPITATION
IN THE MOUNTAINS WILL DECREASE ON WEDNESDAY. THE SNOW LEVEL WILL BE
6500 TO 7500 FT. STORM TOTAL RAINFALL OF 2.5 TO 5 INCHES SEEMS
REASONABLE FOR THE NEXT 36 HOURS...HOWEVER THE 00Z TUE MODEL RUNS
DID BACK OFF ON PRECIPITATION AMOUNTS.

AFTER THE BRIEF LULL ON WEDNESDAY...A RATHER VIGOROUS COLD FRONT
WILL MOVE THROUGH THE PACIFIC NORTHWEST WEDNESDAY NIGHT AND
THANKSGIVING...FOLLOWED QUICKLY BY ANOTHER FRONT DIGGING ACROSS THE
AREA FROM THE NORTHWEST THURSDAY NIGHT. THIS WILL BE ANOTHER RAINY
AND WINDY PERIOD. PRECIPITATION AMOUNTS IN THE OLYMPICS AND NORTH
CASCADES COULD BE IN THE 3 TO 5 INCH RANGE...WITH THE SNOW LEVEL
MAINLY IN THE 5500 TO 7000 FT RANGE.   MCDONNAL

.LONG TERM...PRECIPITATION OVER WESTERN WASHINGTON SHOULD DECREASE
ON FRIDAY...IN THE WAKE OF THE FRONT THAT DIGS THROUGH THE AREA
THURSDAY NIGHT. MODELS HAVE COME INTO FAIRLY STRONG AGREEMENT THAT
AN UPPER TROUGH WILL DIG INTO THE AREA FROM THE NORTHWEST FRIDAY
NIGHT AND SATURDAY...WHILE SURFACE HIGH PRESSURE OVER SOUTHERN
BRITISH COLUMBIA PRODUCES NORTHEAST PRESSURE GRADIENTS. THE WEEKEND
WILL BE QUITE COOL WITH LOWS IN THE MID 20S TO LOWER 30S AND HIGHS
IN THE MID 30S TO MID 40S. THE DAYS SHOULD BE AT LEAST PARTLY SUNNY.
WE WILL KEEP A LOW-END CHANCE OF A SHOWER IN THE FORECAST FOR
NOW...BUT ANY PRECIPITATION WOULD BE VERY LIGHT. IT LOOKS LIKE THE
COOL DRY SPELL WILL BE SHORT LIVED...WITH ANOTHER FRONTAL SYSTEM
LIFTING INTO WESTERN WASHINGTON FROM THE SOUTHWEST SUNDAY NIGHT OR
MONDAY.   MCDONNAL

&&

.HYDROLOGY...AS MENTIONED ABOVE 2.5 TO 5 INCHES OF PRECIPITATION IS
LIKELY ALONG THE WEST SLOPES OF THE CASCADES TODAY THROUGH
WEDNESDAY...WITH THE MAJORITY OF THAT FALLING TODAY AND TONIGHT.
MODELS AGREE WELL THAT THE FOCUS OF HEAVY RAIN WILL BE OVER THE
WASHINGTON CASCADES FROM AROUND SNOQUALMIE PASS SOUTHWARD THIS
MORNING...THEN GRADUALLY SHIFT NORTHWARD THIS AFTERNOON AND
TONIGHT...AND THEN DECREASE ON WEDNESDAY. THE SNOW LEVEL WILL BE IN
THE 6500 TO 7500 FT RANGE.

THE PRECIPITATION AMOUNTS EXPECTED ARE HEAVY BUT NOT EXTREME...AND
IT IS ALSO WORTH NOTING THAT THE 00Z TUE MODEL RUNS BACKED OFF
SLIGHTLY ON PRECIPITATION AMOUNTS. SO WE ARE STILL LOOKING AT A
THREAT OF GENERALLY MINOR FLOODING ON THE MOST FLOOD-PRONE OF THE
RIVERS THAT FLOW OFF THE WEST SLOPES OF THE CASCADES. A FLOOD WATCH
IS IN EFFECT FOR THIS...WHICH WILL BE UPDATED EARLY THIS MORNING.
THAT INCLUDES THE COWLITZ...PUYALLUP NEAR ORTING...SNOQUALMIE...
TOLT...SKYKOMISH...SNOHOMISH...STILLAGUAMISH...AND NOOKSACK RIVERS.

THERE WILL BE A LULL IN RAINFALL ON WEDNESDAY...BUT WE MIGHT NOT BE
OUT OF THE WOODS YET. AS DISCUSSED ABOVE...ANOTHER VIGOROUS FRONTAL
SYSTEM WILL MOVE THROUGH THE AREA WEDNESDAY NIGHT THROUGH THURSDAY
NIGHT...BRINGING PRECIPITATION AMOUNTS OF 3 TO 5 INCHES TO THE
OLYMPICS AND NORTH CASCADES. THE SNOW LEVEL FOR THAT EVENT WILL BE
IN THE 5500 TO 7000 FT RANGE.   MCDONNAL

&&

.AVIATION...MODERATE WEST TO NORTHWEST FLOW ALOFT. A STATIONARY
FRONT OVER THE AREA WILL GIVE LOW MVFR TO IFR CEILINGS AND
VISIBILITIES IN RAIN TO MOST TERMINALS. THE FRONT WILL START TO LIFT
NORTHWARD AS A WARM FRONT LATE THIS AFTERNOON AND WILL REACH THE
CANADIAN BORDER AROUND MIDNIGHT TONIGHT.

MODERATE LOW LEVEL SOUTHWEST FLOW JUST TO THE SOUTH OF THE AREA
EARLY THIS MORNING WILL SPREAD NORTHWARD BEHIND THE WARM FRONT THIS
AFTERNOON INTO TONIGHT. A SLIGHT IMPROVEMENT TO VISIBILITIES AND
CEILINGS CAN BE EXPECTED BEHIND THE WARM FRONT. ALBRECHT

KSEA...CIGS AROUND 005 WITH VIS 3-5SM IN -RA BR. THE WARM FRONT WILL
LIFT NORTH ACROSS THE TERMINAL ABOUT 00Z THIS AFTERNOON WITH VIS
RISING TO P6SM AND CIGS RISING TO 008-012. S WIND 8-12 KT WILL
BECOME LIGHT AFTER 14Z...THEN WILL BECOME 20010-14KT BEHIND THE WARM
FRONT ABOUT 00Z. W WIND 35-40 KT AT FL030 THROUGH THIS EVENING.
ALBRECHT

&&

.MARINE...A NEARLY STATIONARY FRONT EXTENDS FROM THE CENTRAL PUGET
SOUND WESTWARD TO 140W. THE FRONT WILL REMAIN STATIONARY THROUGH
MIDDAY TODAY THEN WILL LIFT NORTH TO THE CANADIAN BORDER ABOUT
MIDNIGHT TONIGHT. EXPECT LIGHT WINDS TO THE N OF THE FRONT TODAY
WITH SMALL CRAFT ADVISORY S TO SW WINDS SPREADING NORTHWARD BEHIND
THE WARM FRONT THIS AFTERNOON AND EVENING. SMALL CRAFT ADVISORY
CONDITIONS WILL COME TO AN END OVER THE NORTHERN WATERS ABOUT 4 AM
EARLY THIS MORNING...THEN WILL PICK UP AGAIN LATE THIS AFTERNOON AND
TONIGHT AS THE WARM FRONT LIFTS NORTHWARD.

WINDY CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE FOR THE NEXT
SEVERAL DAYS. A COLD FRONT WILL SWEEP EASTWARD THROUGH THE WATERS
WEDNESDAY NIGHT. MOST WATERS WILL SEE 20-30 KT SWLY WINDS AHEAD OF
THE FRONT...BUT THE COASTAL WATERS AND PORTIONS OF THE NORTHERN
INLAND WATERS MAY SEE GALE FORCE WINDS.

ANOTHER COLD FRONT WILL DROP SOUTHWARD THROUGH THE WATERS ON FRIDAY.
THIS FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND STRONG N TO NELY WINDS OVER THE OTHER WATERS.
LATER FRI INTO SAT. ALBRECHT

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCH IN EFFECT FOR PORTIONS OF THE AREA.
PZ...SMALL CRAFT ADVISORY COASTAL WATERS AND WEST ENTRANCE TO THE
       STRAIT OF JUAN DE FUCA.
     SMALL CRAFT ADVISORY CENTRAL AND EAST STRAIT OF JUAN DE FUCA
      AND PUGET SOUND AND HOOD CANAL UNTIL 4 AM EARLY THIS MORNING.
     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML








000
FXUS66 KSEW 251156
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
300 AM PST TUE NOV 25 2014

.SYNOPSIS...A WARM FRONT WILL BRING RAINY BREEZY WEATHER TO WESTERN
WASHINGTON TODAY AND TONIGHT...WITH HEAVY RAIN IN THE MOUNTAINS.
AFTER A RELATIVE LULL WEDNESDAY...ANOTHER FRONTAL SYSTEM WILL BRING
MORE RAINY WINDY WEATHER WEDNESDAY NIGHT AND THANKSGIVING. RAIN WILL
DECREASE FRIDAY AS THE COLD FRONT MOVES SOUTHEAST...AND COLDER DRIER
WEATHER IS EXPECTED FOR THE WEEKEND.

&&

.SHORT TERM...MOIST WEST-NORTHWEST FLOW CONTINUES ALOFT OVER WESTERN
WASHINGTON...JUST DOWNSTREAM OF THE FLAT UPPER RIDGE CENTERED
OFFSHORE ALONG 130W. THE WARM FRONT MOVING INTO THE AREA OVERNIGHT
RENEWED WIDESPREAD RAINFALL...AND TEMPERATURES ROSE SLIGHTLY INTO
THE UPPER 40S TO LOWER 50S.

A BAROCLINIC BAND CARRYING SUB-TROPICAL MOISTURE OVER THE NORTH SIDE
OF THE OFFSHORE RIDGE WILL CONTINUE TO BRING RAIN TO WESTERN
WASHINGTON TODAY. THE MODELS HAVE COME INTO FAIRLY STRONG AGREEMENT
THAT THE BAND WILL BEGIN LIFTING NORTHWARD TONIGHT AND WEDNESDAY...
AS THE RIDGE OFFSHORE AMPLIFIES AHEAD OF ANOTHER APPROACHING FRONTAL
SYSTEM.

THE WESTERN WASHINGTON LOWLANDS WILL RECEIVE FAIRLY SIGNIFICANT
RAINFALL THIS MORNING -- UP TO 0.75 INCH IN PLACES. FROM THE PUGET
SOUND AREA SOUTHWARD...THE RAIN SHOULD GENERALLY LET UP DURING THE
DAY. RAINFALL AMOUNTS OVER THE LOWLANDS WILL BE LESS TONIGHT AND
LESS YET ON WEDNESDAY...WITH THE PUGET SOUND REGION LARGELY IN THE
RAIN SHADOW OF THE OLYMPICS MUCH OF THE TIME. IT WILL ALSO BE BREEZY
AT TIMES OVER THE LOWLANDS TONIGHT AND WEDNESDAY.

THIS PATTERN FAVORS HEAVY RAIN IN THE CASCADES...AS WE HAVE BEEN
ADVERTISING FOR SEVERAL DAYS. IT WILL BE FOCUSED ON THE WASHINGTON
CASCADES FROM ABOUT SNOQUALMIE PASS SOUTHWARD THIS MORNING...THEN
GRADUALLY SHIFT NORTHWARD THIS AFTERNOON AND TONIGHT. PRECIPITATION
IN THE MOUNTAINS WILL DECREASE ON WEDNESDAY. THE SNOW LEVEL WILL BE
6500 TO 7500 FT. STORM TOTAL RAINFALL OF 2.5 TO 5 INCHES SEEMS
REASONABLE FOR THE NEXT 36 HOURS...HOWEVER THE 00Z TUE MODEL RUNS
DID BACK OFF ON PRECIPITATION AMOUNTS.

AFTER THE BRIEF LULL ON WEDNESDAY...A RATHER VIGOROUS COLD FRONT
WILL MOVE THROUGH THE PACIFIC NORTHWEST WEDNESDAY NIGHT AND
THANKSGIVING...FOLLOWED QUICKLY BY ANOTHER FRONT DIGGING ACROSS THE
AREA FROM THE NORTHWEST THURSDAY NIGHT. THIS WILL BE ANOTHER RAINY
AND WINDY PERIOD. PRECIPITATION AMOUNTS IN THE OLYMPICS AND NORTH
CASCADES COULD BE IN THE 3 TO 5 INCH RANGE...WITH THE SNOW LEVEL
MAINLY IN THE 5500 TO 7000 FT RANGE.   MCDONNAL

.LONG TERM...PRECIPITATION OVER WESTERN WASHINGTON SHOULD DECREASE
ON FRIDAY...IN THE WAKE OF THE FRONT THAT DIGS THROUGH THE AREA
THURSDAY NIGHT. MODELS HAVE COME INTO FAIRLY STRONG AGREEMENT THAT
AN UPPER TROUGH WILL DIG INTO THE AREA FROM THE NORTHWEST FRIDAY
NIGHT AND SATURDAY...WHILE SURFACE HIGH PRESSURE OVER SOUTHERN
BRITISH COLUMBIA PRODUCES NORTHEAST PRESSURE GRADIENTS. THE WEEKEND
WILL BE QUITE COOL WITH LOWS IN THE MID 20S TO LOWER 30S AND HIGHS
IN THE MID 30S TO MID 40S. THE DAYS SHOULD BE AT LEAST PARTLY SUNNY.
WE WILL KEEP A LOW-END CHANCE OF A SHOWER IN THE FORECAST FOR
NOW...BUT ANY PRECIPITATION WOULD BE VERY LIGHT. IT LOOKS LIKE THE
COOL DRY SPELL WILL BE SHORT LIVED...WITH ANOTHER FRONTAL SYSTEM
LIFTING INTO WESTERN WASHINGTON FROM THE SOUTHWEST SUNDAY NIGHT OR
MONDAY.   MCDONNAL

&&

.HYDROLOGY...AS MENTIONED ABOVE 2.5 TO 5 INCHES OF PRECIPITATION IS
LIKELY ALONG THE WEST SLOPES OF THE CASCADES TODAY THROUGH
WEDNESDAY...WITH THE MAJORITY OF THAT FALLING TODAY AND TONIGHT.
MODELS AGREE WELL THAT THE FOCUS OF HEAVY RAIN WILL BE OVER THE
WASHINGTON CASCADES FROM AROUND SNOQUALMIE PASS SOUTHWARD THIS
MORNING...THEN GRADUALLY SHIFT NORTHWARD THIS AFTERNOON AND
TONIGHT...AND THEN DECREASE ON WEDNESDAY. THE SNOW LEVEL WILL BE IN
THE 6500 TO 7500 FT RANGE.

THE PRECIPITATION AMOUNTS EXPECTED ARE HEAVY BUT NOT EXTREME...AND
IT IS ALSO WORTH NOTING THAT THE 00Z TUE MODEL RUNS BACKED OFF
SLIGHTLY ON PRECIPITATION AMOUNTS. SO WE ARE STILL LOOKING AT A
THREAT OF GENERALLY MINOR FLOODING ON THE MOST FLOOD-PRONE OF THE
RIVERS THAT FLOW OFF THE WEST SLOPES OF THE CASCADES. A FLOOD WATCH
IS IN EFFECT FOR THIS...WHICH WILL BE UPDATED EARLY THIS MORNING.
THAT INCLUDES THE COWLITZ...PUYALLUP NEAR ORTING...SNOQUALMIE...
TOLT...SKYKOMISH...SNOHOMISH...STILLAGUAMISH...AND NOOKSACK RIVERS.

THERE WILL BE A LULL IN RAINFALL ON WEDNESDAY...BUT WE MIGHT NOT BE
OUT OF THE WOODS YET. AS DISCUSSED ABOVE...ANOTHER VIGOROUS FRONTAL
SYSTEM WILL MOVE THROUGH THE AREA WEDNESDAY NIGHT THROUGH THURSDAY
NIGHT...BRINGING PRECIPITATION AMOUNTS OF 3 TO 5 INCHES TO THE
OLYMPICS AND NORTH CASCADES. THE SNOW LEVEL FOR THAT EVENT WILL BE
IN THE 5500 TO 7000 FT RANGE.   MCDONNAL

&&

.AVIATION...MODERATE WEST TO NORTHWEST FLOW ALOFT. A STATIONARY
FRONT OVER THE AREA WILL GIVE LOW MVFR TO IFR CEILINGS AND
VISIBILITIES IN RAIN TO MOST TERMINALS. THE FRONT WILL START TO LIFT
NORTHWARD AS A WARM FRONT LATE THIS AFTERNOON AND WILL REACH THE
CANADIAN BORDER AROUND MIDNIGHT TONIGHT.

MODERATE LOW LEVEL SOUTHWEST FLOW JUST TO THE SOUTH OF THE AREA
EARLY THIS MORNING WILL SPREAD NORTHWARD BEHIND THE WARM FRONT THIS
AFTERNOON INTO TONIGHT. A SLIGHT IMPROVEMENT TO VISIBILITIES AND
CEILINGS CAN BE EXPECTED BEHIND THE WARM FRONT. ALBRECHT

KSEA...CIGS AROUND 005 WITH VIS 3-5SM IN -RA BR. THE WARM FRONT WILL
LIFT NORTH ACROSS THE TERMINAL ABOUT 00Z THIS AFTERNOON WITH VIS
RISING TO P6SM AND CIGS RISING TO 008-012. S WIND 8-12 KT WILL
BECOME LIGHT AFTER 14Z...THEN WILL BECOME 20010-14KT BEHIND THE WARM
FRONT ABOUT 00Z. W WIND 35-40 KT AT FL030 THROUGH THIS EVENING.
ALBRECHT

&&

.MARINE...A NEARLY STATIONARY FRONT EXTENDS FROM THE CENTRAL PUGET
SOUND WESTWARD TO 140W. THE FRONT WILL REMAIN STATIONARY THROUGH
MIDDAY TODAY THEN WILL LIFT NORTH TO THE CANADIAN BORDER ABOUT
MIDNIGHT TONIGHT. EXPECT LIGHT WINDS TO THE N OF THE FRONT TODAY
WITH SMALL CRAFT ADVISORY S TO SW WINDS SPREADING NORTHWARD BEHIND
THE WARM FRONT THIS AFTERNOON AND EVENING. SMALL CRAFT ADVISORY
CONDITIONS WILL COME TO AN END OVER THE NORTHERN WATERS ABOUT 4 AM
EARLY THIS MORNING...THEN WILL PICK UP AGAIN LATE THIS AFTERNOON AND
TONIGHT AS THE WARM FRONT LIFTS NORTHWARD.

WINDY CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE FOR THE NEXT
SEVERAL DAYS. A COLD FRONT WILL SWEEP EASTWARD THROUGH THE WATERS
WEDNESDAY NIGHT. MOST WATERS WILL SEE 20-30 KT SWLY WINDS AHEAD OF
THE FRONT...BUT THE COASTAL WATERS AND PORTIONS OF THE NORTHERN
INLAND WATERS MAY SEE GALE FORCE WINDS.

ANOTHER COLD FRONT WILL DROP SOUTHWARD THROUGH THE WATERS ON FRIDAY.
THIS FRONT WILL BE FOLLOWED BY STRONG FRASER OUTFLOW IN THE NORTHERN
INLAND WATERS AND STRONG N TO NELY WINDS OVER THE OTHER WATERS.
LATER FRI INTO SAT. ALBRECHT

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCH IN EFFECT FOR PORTIONS OF THE AREA.
PZ...SMALL CRAFT ADVISORY COASTAL WATERS AND WEST ENTRANCE TO THE
       STRAIT OF JUAN DE FUCA.
     SMALL CRAFT ADVISORY CENTRAL AND EAST STRAIT OF JUAN DE FUCA
      AND PUGET SOUND AND HOOD CANAL UNTIL 4 AM EARLY THIS MORNING.
     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML







000
FXUS66 KSEW 250453
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
900 PM PST MON NOV 24 2014...CORRECTED HEADLINE FORMAT

.SYNOPSIS...A WARM FRONT WILL BRING RAIN...MILD TEMPERATURES AND
LOCALLY WINDY WEATHER TO WESTERN WASHINGTON THROUGH TUESDAY NIGHT. A
WEAK COLD FRONT WILL MOVE ACROSS THE AREA WEDNESDAY NIGHT. ANOTHER
WARM FRONT WILL BRING A LITTLE MORE RAIN ON THANKSGIVING. A COLD
FRONT WILL MOVE SLOWLY SOUTH ACROSS THE AREA FRIDAY AND FRIDAY
NIGHT. AN UPPER LEVEL RIDGE MAY BRING A COOLER DRIER PERIOD THIS
WEEKEND.

&&

.SHORT TERM...THE FIRST IN A SERIES OF SHORT WAVES RIDING OVER THE
TOP OF THE RIDGE CONTINUES TO PRODUCE RAIN ACROSS THE AREA. RAINFALL
TOTALS WITH THIS FIRST FEATURE HAVE SO FAR NOT BEEN ALL THAT
IMPRESSIVE WITH 1 TO LOCALLY 2 INCHES IN THE MOUNTAINS AND GENERALLY
LESS THAN A QUARTER INCH ACROSS THE LOWLANDS. RADAR SHOWS A RELATIVE
LULL IN RAINFALL WHICH WILL LIKELY CONTINUE UNTIL THE NEXT WAVE
REACHES THE AREA LATER TONIGHT.

MODELS ARE IN GOOD AGREEMENT THAT WARM ADVECTION RAINFALL
RE-DEVELOPS LATER TONIGHT INTO TUESDAY. RAIN AMOUNTS WITH THIS NEXT
FEATURE SHOULD BE A BIT MORE IMPRESSIVE...POSSIBLY 2-3 MORE INCHES
IN THE CASCADES AND UP TO 2 INCHES ALONG THE W SLOPES OF THE
OLYMPICS. THE LOWLANDS SHOULD ALSO HAVE SOME MODERATE RAIN AT
TIMES...ESPECIALLY DURING EARLY WHICH COULD IMPACT THE MORNING
COMMUTE. AMOUNTS OF A HALF INCH IN A FEW HOURS TIME COULD CAUSE SOME
TRAVEL DIFFICULTIES DUE TO PONDING OF WATER ON ROADWAYS. WILL NEED
TO MONITOR RAINFALL RATES IN THE LOWLANDS AS WELL AS THE MOUNTAINS.
OVERALL...THE NEWER 00Z MODELS ARE NOT SHOWING MUCH CHANGE IN THE
WET PATTERN THROUGH THURSDAY.

THE WARM FRONTAL WAVE PRODUCING LOCALLY HEAVY RAIN TUESDAY WILL LIFT
NWD BY WEDNESDAY. THIS WILL ALLOW FOR SOME REPRIEVE IN STEADY RAIN
ACROSS S/CENTRAL PORTIONS OF WRN WA. HOWEVER...THE MOISTURE BAND MAY
STILL PRODUCE RAIN AT TIMES ACROSS THE FAR N CASCADES AND POSSIBLY
THE OLYMPICS. ANY ADDITIONAL RAIN IN THESE AREAS WILL ONLY INCREASE
THE THREAT OF FLOODING ON RIVER BASINS AFFECTED BY STRONG WLY FLOW.
SEE THE HYDRO DISCUSSION FOR DETAILS.

THE ASSOCIATED COLD FRONT WILL FINALLY SWING INTO WRN WA ON
THURSDAY. STRONGER S/SW FLOW ALOFT WILL ADD TO RAIN AMOUNTS IN THE
SKOKOMISH RIVER BASIN WHICH WILL HEIGHTEN THE FLOOD RISK THERE.
WHILE THIS FRONT COULD TEMPORARILY WORSEN THE FLOOD
THREAT...PRECIPITATION WILL FINALLY EASE BEHIND THE FRONT FRIDAY
NIGHT. MERCER


.LONG TERM...NO UPDATES FROM PREVIOUS DISCUSSION...ON FRIDAY AND
FRIDAY NIGHT THE ECMWF AND GFS AGREE ON MOVING A COLD FRONT
SOUTHWARD ACROSS THE AREA. THIS FEATURE IS ACTUALLY THE LEFTOVER
OCCLUDED FRONT FROM THE MAIN LOW OFFSHORE. COOLER DRIER N FLOW ALOFT
AND AT LOW LEVELS WILL SPREAD S BEHIND THE FRONT FRIDAY NIGHT AND
SATURDAY MORNING AS AN UPPER LEVEL RIDGE BUILDS OFFSHORE AND A
SURFACE HIGH SHIFTS S OVER B.C.  COULD GET SOME BREEZY NE OUTFLOW
OVER THE N INTERIOR FRIDAY NIGHT THROUGH SUNDAY.

BOTH THE 12Z/18Z GFS AND 12Z ECMWF KEEP THE AREA DRY ON SUNDAY AS
WELL BUT RUN-TO-RUN CONSISTENCY IS NOT GOOD YET...SO CONFIDENCE IS
LOW. LOW CHANCE POPS ARE STILL IN THE FORECAST FOR BOTH SATURDAY AND
SUNDAY...BUT IF THE MODELS STICK WITH THIS SOLUTION SATURDAY AND
POSSIBLY EVEN SUNDAY COULD BE DRIED OUT AND SUNSHINE INCREASED. THE
COOL DRY FRASER RIVER VALLEY OUTFLOW AIR WILL LOWER SNOW LEVELS
CLOSE TO THE SURFACE...BUT MENTION OF SNOW HAS BEEN DROPPED FROM THE
FORECAST SINCE CONFIDENCE IS STILL LOW.

IF MODELS DO BRING PRECIP BACK OVER THE AREA THIS WEEKEND IT WILL
PROBABLY BE FROM AN UPPER LEVEL LOW W OF THE OREGON COAST SPREADING
WARM MOIST AIR NORTHWARD OVER THE AREA. KAM

&&

.HYDROLOGY...ONLY MINOR UPDATES TO PREVIOUS DISCUSSION...WRN WA
INCLUDING THE CASCADES WILL SEE A LULL IN RAINFALL THROUGH AT LEAST
MIDNIGHT. STRONG WARM ADVECTION WILL RE-DEVELOP LATE TONIGHT AND
TUESDAY MORNING...FOCUSED ON THE CENTRAL CASCADES FROM ABOUT
SNOQUALMIE PASS SOUTHWARD. THIS WILL AFFECT MAINLY THE PUYALLUP AND
COWLITZ RIVERS.

THE WARM FRONT WILL SHIFT SLOWLY N TUESDAY AFTERNOON AND NIGHT
SHIFTING THE HEAVIEST RAIN TO THE NORTH CASCADES. THIS WILL AFFECT
MULTIPLE RIVER BASINS INCLUDING THE SNOQUALMIE...STILLAGUAMISH...
SKAGIT...AND NOOKSACK.

THE WARM FRONT WILL LIKELY SHIFT OVER B.C. AROUND 12Z WEDNESDAY. THE
QPF FORECAST IS A BLEND OF THE MESOSCALE MODELS AND HAS 3 TO 4.5
INCHES SPREAD GENERALLY ACROSS THE CASCADES IN THE 48 HOUR PERIOD
ENDING 18Z WEDNESDAY. BULLSEYES OF 5 TO 7 INCHES ARE PRESENT OVER MT
BAKER AND MT RAINIER RESPECTIVELY. THERE IS STILL A LOT OF
UNCERTAINTY REGARDING THIS HEAVY RAIN EVENT...WITH INTENSITY OF THE
RAIN AND EXACTLY WHERE AND HOW LONG THE HEAVIEST PRECIP WILL FALL. A
FLOOD WATCH WAS ISSUED EARLIER THIS AFTERNOON COVERING THE CASCADES.

MODELS SHOW THE OLYMPICS GETTING LOWER AMOUNTS OF RAIN...BUT THERE
IS GREATER UNCERTAINTY WHETHER THIS W FLOW EVENT MIGHT DRIVE THE
BOGACHIEL RIVER TO FLOOD STAGE. THE EARLIER HYDROLOGIC OUTLOOK
COVERS THE HIGHER UNCERTAINTY OVER THE OLYMPICS.

AFTER THE WARM FRONT MOVES N ON WEDNESDAY MORNING THERE WILL BE A
SHORT LULL IN THE PRECIP. A WEAK COLD FRONT WILL MOVE THROUGH THE
AREA WEDNESDAY EVENING BRINGING A QUICK SHOT OF MODERATE RAIN.
ANOTHER BATCH OF WARM ADVECTION DEVELOPS BEHIND THE COLD FRONT FOR A
SECOND PERIOD OF MODERATE TO HEAVY RAIN FOR THE OLYMPICS AND N
CASCADES. KAM/MERCER

&&

.AVIATION...MODERATE WEST TO NORTHWEST FLOW ALOFT. A STATIONARY
FRONT WILL REMAIN OVER THE AREA THROUGH MIDDAY TUESDAY GIVING LOW
MVFR TO IFR CEILINGS AND VISIBILITIES IN RAIN TO MOST TERMINALS. THE
FRONT WILL START TO LIFT NORTHWARD AS A WARM FRONT LATE TUESDAY
AFTERNOON INTO TUESDAY NIGHT.

MODERATE LOW LEVEL SOUTHWEST FLOW OVER SOUTHERN PORTIONS OF THE AREA
TUESDAY MORNING WILL SPREAD NORTHWARD BEHIND THE WARM FRONT TUESDAY
AFTERNOON INTO TUESDAY NIGHT. A SLIGHT IMPROVEMENT TO
VISIBILITIES AND CEILINGS CAN BE EXPECTED LATE TUESDAY AFTERNOON AND
TUESDAY EVENING TO THE SOUTH OF THE WARM FRONT. ALBRECHT

KSEA...CIGS AROUND 015 TONIGHT WILL FALL TO 007-010 12Z THROUGH 22Z
TUE. SE WIND 7-10 KT WITH WIND SW 35 KT AT 020. ALBRECHT

&&

.MARINE...A NEARLY STATIONARY FRONT EXTENDS FROM THE CENTRAL PUGET
SOUND WESTWARD TO 140W. THE FRONT WILL REMAIN STATIONARY THROUGH
TUESDAY MORNING THEN WILL SLOWLY LIFT NORTH AS A WARM FRONT INTO
SOUTHERN BRITISH COLUMBIA TUESDAY NIGHT THROUGH WEDNESDAY. EXPECT
WINDS TO BECOME LIGHT LATE TONIGHT INTO TUESDAY MORNING. THEN SMALL
CRAFT ADVISORY SOUTHWEST WINDS 15 TO 30 KNOTS ARE EXPECTED TO SPREAD
NORTH THROUGH MOST OF THE WATERS MIDDAY TUESDAY THROUGH TUESDAY
NIGHT AS THE FRONT LIFTS NORTHWARD.

WINDY CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE FOR THE NEXT
SEVERAL DAYS. A COLD FRONT WILL SWEEP EASTWARD THROUGH THE WATERS
WEDNESDAY NIGHT OR THURSDAY. THIS FRONT WILL BE FOLLOWED BY ANOTHER
COLD FRONT THAT WILL DROP SOUTHWARD THROUGH THE WATERS ON FRIDAY.

STRONG OFFSHORE FLOW AND FRASER OUTFLOW ARE EXPECTED TO DEVELOP
LATER FRI INTO SAT AS COLD HIGH PRES MOVES INTO THE INTERIOR OF
BRITISH COLUMBIA. ALBRECHT

$$

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES IN EFFECT FOR PORTIONS OF WESTERN WASHINGTON.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML


















000
FXUS66 KSEW 250453
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
900 PM PST MON NOV 24 2014...CORRECTED HEADLINE FORMAT

.SYNOPSIS...A WARM FRONT WILL BRING RAIN...MILD TEMPERATURES AND
LOCALLY WINDY WEATHER TO WESTERN WASHINGTON THROUGH TUESDAY NIGHT. A
WEAK COLD FRONT WILL MOVE ACROSS THE AREA WEDNESDAY NIGHT. ANOTHER
WARM FRONT WILL BRING A LITTLE MORE RAIN ON THANKSGIVING. A COLD
FRONT WILL MOVE SLOWLY SOUTH ACROSS THE AREA FRIDAY AND FRIDAY
NIGHT. AN UPPER LEVEL RIDGE MAY BRING A COOLER DRIER PERIOD THIS
WEEKEND.

&&

.SHORT TERM...THE FIRST IN A SERIES OF SHORT WAVES RIDING OVER THE
TOP OF THE RIDGE CONTINUES TO PRODUCE RAIN ACROSS THE AREA. RAINFALL
TOTALS WITH THIS FIRST FEATURE HAVE SO FAR NOT BEEN ALL THAT
IMPRESSIVE WITH 1 TO LOCALLY 2 INCHES IN THE MOUNTAINS AND GENERALLY
LESS THAN A QUARTER INCH ACROSS THE LOWLANDS. RADAR SHOWS A RELATIVE
LULL IN RAINFALL WHICH WILL LIKELY CONTINUE UNTIL THE NEXT WAVE
REACHES THE AREA LATER TONIGHT.

MODELS ARE IN GOOD AGREEMENT THAT WARM ADVECTION RAINFALL
RE-DEVELOPS LATER TONIGHT INTO TUESDAY. RAIN AMOUNTS WITH THIS NEXT
FEATURE SHOULD BE A BIT MORE IMPRESSIVE...POSSIBLY 2-3 MORE INCHES
IN THE CASCADES AND UP TO 2 INCHES ALONG THE W SLOPES OF THE
OLYMPICS. THE LOWLANDS SHOULD ALSO HAVE SOME MODERATE RAIN AT
TIMES...ESPECIALLY DURING EARLY WHICH COULD IMPACT THE MORNING
COMMUTE. AMOUNTS OF A HALF INCH IN A FEW HOURS TIME COULD CAUSE SOME
TRAVEL DIFFICULTIES DUE TO PONDING OF WATER ON ROADWAYS. WILL NEED
TO MONITOR RAINFALL RATES IN THE LOWLANDS AS WELL AS THE MOUNTAINS.
OVERALL...THE NEWER 00Z MODELS ARE NOT SHOWING MUCH CHANGE IN THE
WET PATTERN THROUGH THURSDAY.

THE WARM FRONTAL WAVE PRODUCING LOCALLY HEAVY RAIN TUESDAY WILL LIFT
NWD BY WEDNESDAY. THIS WILL ALLOW FOR SOME REPRIEVE IN STEADY RAIN
ACROSS S/CENTRAL PORTIONS OF WRN WA. HOWEVER...THE MOISTURE BAND MAY
STILL PRODUCE RAIN AT TIMES ACROSS THE FAR N CASCADES AND POSSIBLY
THE OLYMPICS. ANY ADDITIONAL RAIN IN THESE AREAS WILL ONLY INCREASE
THE THREAT OF FLOODING ON RIVER BASINS AFFECTED BY STRONG WLY FLOW.
SEE THE HYDRO DISCUSSION FOR DETAILS.

THE ASSOCIATED COLD FRONT WILL FINALLY SWING INTO WRN WA ON
THURSDAY. STRONGER S/SW FLOW ALOFT WILL ADD TO RAIN AMOUNTS IN THE
SKOKOMISH RIVER BASIN WHICH WILL HEIGHTEN THE FLOOD RISK THERE.
WHILE THIS FRONT COULD TEMPORARILY WORSEN THE FLOOD
THREAT...PRECIPITATION WILL FINALLY EASE BEHIND THE FRONT FRIDAY
NIGHT. MERCER


.LONG TERM...NO UPDATES FROM PREVIOUS DISCUSSION...ON FRIDAY AND
FRIDAY NIGHT THE ECMWF AND GFS AGREE ON MOVING A COLD FRONT
SOUTHWARD ACROSS THE AREA. THIS FEATURE IS ACTUALLY THE LEFTOVER
OCCLUDED FRONT FROM THE MAIN LOW OFFSHORE. COOLER DRIER N FLOW ALOFT
AND AT LOW LEVELS WILL SPREAD S BEHIND THE FRONT FRIDAY NIGHT AND
SATURDAY MORNING AS AN UPPER LEVEL RIDGE BUILDS OFFSHORE AND A
SURFACE HIGH SHIFTS S OVER B.C.  COULD GET SOME BREEZY NE OUTFLOW
OVER THE N INTERIOR FRIDAY NIGHT THROUGH SUNDAY.

BOTH THE 12Z/18Z GFS AND 12Z ECMWF KEEP THE AREA DRY ON SUNDAY AS
WELL BUT RUN-TO-RUN CONSISTENCY IS NOT GOOD YET...SO CONFIDENCE IS
LOW. LOW CHANCE POPS ARE STILL IN THE FORECAST FOR BOTH SATURDAY AND
SUNDAY...BUT IF THE MODELS STICK WITH THIS SOLUTION SATURDAY AND
POSSIBLY EVEN SUNDAY COULD BE DRIED OUT AND SUNSHINE INCREASED. THE
COOL DRY FRASER RIVER VALLEY OUTFLOW AIR WILL LOWER SNOW LEVELS
CLOSE TO THE SURFACE...BUT MENTION OF SNOW HAS BEEN DROPPED FROM THE
FORECAST SINCE CONFIDENCE IS STILL LOW.

IF MODELS DO BRING PRECIP BACK OVER THE AREA THIS WEEKEND IT WILL
PROBABLY BE FROM AN UPPER LEVEL LOW W OF THE OREGON COAST SPREADING
WARM MOIST AIR NORTHWARD OVER THE AREA. KAM

&&

.HYDROLOGY...ONLY MINOR UPDATES TO PREVIOUS DISCUSSION...WRN WA
INCLUDING THE CASCADES WILL SEE A LULL IN RAINFALL THROUGH AT LEAST
MIDNIGHT. STRONG WARM ADVECTION WILL RE-DEVELOP LATE TONIGHT AND
TUESDAY MORNING...FOCUSED ON THE CENTRAL CASCADES FROM ABOUT
SNOQUALMIE PASS SOUTHWARD. THIS WILL AFFECT MAINLY THE PUYALLUP AND
COWLITZ RIVERS.

THE WARM FRONT WILL SHIFT SLOWLY N TUESDAY AFTERNOON AND NIGHT
SHIFTING THE HEAVIEST RAIN TO THE NORTH CASCADES. THIS WILL AFFECT
MULTIPLE RIVER BASINS INCLUDING THE SNOQUALMIE...STILLAGUAMISH...
SKAGIT...AND NOOKSACK.

THE WARM FRONT WILL LIKELY SHIFT OVER B.C. AROUND 12Z WEDNESDAY. THE
QPF FORECAST IS A BLEND OF THE MESOSCALE MODELS AND HAS 3 TO 4.5
INCHES SPREAD GENERALLY ACROSS THE CASCADES IN THE 48 HOUR PERIOD
ENDING 18Z WEDNESDAY. BULLSEYES OF 5 TO 7 INCHES ARE PRESENT OVER MT
BAKER AND MT RAINIER RESPECTIVELY. THERE IS STILL A LOT OF
UNCERTAINTY REGARDING THIS HEAVY RAIN EVENT...WITH INTENSITY OF THE
RAIN AND EXACTLY WHERE AND HOW LONG THE HEAVIEST PRECIP WILL FALL. A
FLOOD WATCH WAS ISSUED EARLIER THIS AFTERNOON COVERING THE CASCADES.

MODELS SHOW THE OLYMPICS GETTING LOWER AMOUNTS OF RAIN...BUT THERE
IS GREATER UNCERTAINTY WHETHER THIS W FLOW EVENT MIGHT DRIVE THE
BOGACHIEL RIVER TO FLOOD STAGE. THE EARLIER HYDROLOGIC OUTLOOK
COVERS THE HIGHER UNCERTAINTY OVER THE OLYMPICS.

AFTER THE WARM FRONT MOVES N ON WEDNESDAY MORNING THERE WILL BE A
SHORT LULL IN THE PRECIP. A WEAK COLD FRONT WILL MOVE THROUGH THE
AREA WEDNESDAY EVENING BRINGING A QUICK SHOT OF MODERATE RAIN.
ANOTHER BATCH OF WARM ADVECTION DEVELOPS BEHIND THE COLD FRONT FOR A
SECOND PERIOD OF MODERATE TO HEAVY RAIN FOR THE OLYMPICS AND N
CASCADES. KAM/MERCER

&&

.AVIATION...MODERATE WEST TO NORTHWEST FLOW ALOFT. A STATIONARY
FRONT WILL REMAIN OVER THE AREA THROUGH MIDDAY TUESDAY GIVING LOW
MVFR TO IFR CEILINGS AND VISIBILITIES IN RAIN TO MOST TERMINALS. THE
FRONT WILL START TO LIFT NORTHWARD AS A WARM FRONT LATE TUESDAY
AFTERNOON INTO TUESDAY NIGHT.

MODERATE LOW LEVEL SOUTHWEST FLOW OVER SOUTHERN PORTIONS OF THE AREA
TUESDAY MORNING WILL SPREAD NORTHWARD BEHIND THE WARM FRONT TUESDAY
AFTERNOON INTO TUESDAY NIGHT. A SLIGHT IMPROVEMENT TO
VISIBILITIES AND CEILINGS CAN BE EXPECTED LATE TUESDAY AFTERNOON AND
TUESDAY EVENING TO THE SOUTH OF THE WARM FRONT. ALBRECHT

KSEA...CIGS AROUND 015 TONIGHT WILL FALL TO 007-010 12Z THROUGH 22Z
TUE. SE WIND 7-10 KT WITH WIND SW 35 KT AT 020. ALBRECHT

&&

.MARINE...A NEARLY STATIONARY FRONT EXTENDS FROM THE CENTRAL PUGET
SOUND WESTWARD TO 140W. THE FRONT WILL REMAIN STATIONARY THROUGH
TUESDAY MORNING THEN WILL SLOWLY LIFT NORTH AS A WARM FRONT INTO
SOUTHERN BRITISH COLUMBIA TUESDAY NIGHT THROUGH WEDNESDAY. EXPECT
WINDS TO BECOME LIGHT LATE TONIGHT INTO TUESDAY MORNING. THEN SMALL
CRAFT ADVISORY SOUTHWEST WINDS 15 TO 30 KNOTS ARE EXPECTED TO SPREAD
NORTH THROUGH MOST OF THE WATERS MIDDAY TUESDAY THROUGH TUESDAY
NIGHT AS THE FRONT LIFTS NORTHWARD.

WINDY CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE FOR THE NEXT
SEVERAL DAYS. A COLD FRONT WILL SWEEP EASTWARD THROUGH THE WATERS
WEDNESDAY NIGHT OR THURSDAY. THIS FRONT WILL BE FOLLOWED BY ANOTHER
COLD FRONT THAT WILL DROP SOUTHWARD THROUGH THE WATERS ON FRIDAY.

STRONG OFFSHORE FLOW AND FRASER OUTFLOW ARE EXPECTED TO DEVELOP
LATER FRI INTO SAT AS COLD HIGH PRES MOVES INTO THE INTERIOR OF
BRITISH COLUMBIA. ALBRECHT

$$

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES IN EFFECT FOR PORTIONS OF WESTERN WASHINGTON.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML



















000
FXUS66 KSEW 250450
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
900 PM PST MON NOV 24 2014

.SYNOPSIS...A WARM FRONT WILL BRING RAIN...MILD TEMPERATURES AND
LOCALLY WINDY WEATHER TO WESTERN WASHINGTON THROUGH TUESDAY NIGHT. A
WEAK COLD FRONT WILL MOVE ACROSS THE AREA WEDNESDAY NIGHT. ANOTHER
WARM FRONT WILL BRING A LITTLE MORE RAIN ON THANKSGIVING. A COLD
FRONT WILL MOVE SLOWLY SOUTH ACROSS THE AREA FRIDAY AND FRIDAY
NIGHT. AN UPPER LEVEL RIDGE MAY BRING A COOLER DRIER PERIOD THIS
WEEKEND.

&&

.SHORT TERM...THE FIRST IN A SERIES OF SHORT WAVES RIDING OVER THE
TOP OF THE RIDGE CONTINUES TO PRODUCE RAIN ACROSS THE AREA. RAINFALL
TOTALS WITH THIS FIRST FEATURE HAVE SO FAR NOT BEEN ALL THAT
IMPRESSIVE WITH 1 TO LOCALLY 2 INCHES IN THE MOUNTAINS AND GENERALLY
LESS THAN A QUARTER INCH ACROSS THE LOWLANDS. RADAR SHOWS A RELATIVE
LULL IN RAINFALL WHICH WILL LIKELY CONTINUE UNTIL THE NEXT WAVE
REACHES THE AREA LATER TONIGHT.

MODELS ARE IN GOOD AGREEMENT THAT WARM ADVECTION RAINFALL
RE-DEVELOPS LATER TONIGHT INTO TUESDAY. RAIN AMOUNTS WITH THIS NEXT
FEATURE SHOULD BE A BIT MORE IMPRESSIVE...POSSIBLY 2-3 MORE INCHES
IN THE CASCADES AND UP TO 2 INCHES ALONG THE W SLOPES OF THE
OLYMPICS. THE LOWLANDS SHOULD ALSO HAVE SOME MODERATE RAIN AT
TIMES...ESPECIALLY DURING EARLY WHICH COULD IMPACT THE MORNING
COMMUTE. AMOUNTS OF A HALF INCH IN A FEW HOURS TIME COULD CAUSE SOME
TRAVEL DIFFICULTIES DUE TO PONDING OF WATER ON ROADWAYS. WILL NEED
TO MONITOR RAINFALL RATES IN THE LOWLANDS AS WELL AS THE MOUNTAINS.
OVERALL...THE NEWER 00Z MODELS ARE NOT SHOWING MUCH CHANGE IN THE
WET PATTERN THROUGH THURSDAY.

THE WARM FRONTAL WAVE PRODUCING LOCALLY HEAVY RAIN TUESDAY WILL LIFT
NWD BY WEDNESDAY. THIS WILL ALLOW FOR SOME REPRIEVE IN STEADY RAIN
ACROSS S/CENTRAL PORTIONS OF WRN WA. HOWEVER...THE MOISTURE BAND MAY
STILL PRODUCE RAIN AT TIMES ACROSS THE FAR N CASCADES AND POSSIBLY
THE OLYMPICS. ANY ADDITIONAL RAIN IN THESE AREAS WILL ONLY INCREASE
THE THREAT OF FLOODING ON RIVER BASINS AFFECTED BY STRONG WLY FLOW.
SEE THE HYDRO DISCUSSION FOR DETAILS.

THE ASSOCIATED COLD FRONT WILL FINALLY SWING INTO WRN WA ON
THURSDAY. STRONGER S/SW FLOW ALOFT WILL ADD TO RAIN AMOUNTS IN THE
SKOKOMISH RIVER BASIN WHICH WILL HEIGHTEN THE FLOOD RISK THERE.
WHILE THIS FRONT COULD TEMPORARILY WORSEN THE FLOOD
THREAT...PRECIPITATION WILL FINALLY EASE BEHIND THE FRONT FRIDAY
NIGHT. MERCER


.LONG TERM...NO UPDATES FROM PREVIOUS DISCUSSION...ON FRIDAY AND
FRIDAY NIGHT THE ECMWF AND GFS AGREE ON MOVING A COLD FRONT
SOUTHWARD ACROSS THE AREA. THIS FEATURE IS ACTUALLY THE LEFTOVER
OCCLUDED FRONT FROM THE MAIN LOW OFFSHORE. COOLER DRIER N FLOW ALOFT
AND AT LOW LEVELS WILL SPREAD S BEHIND THE FRONT FRIDAY NIGHT AND
SATURDAY MORNING AS AN UPPER LEVEL RIDGE BUILDS OFFSHORE AND A
SURFACE HIGH SHIFTS S OVER B.C.  COULD GET SOME BREEZY NE OUTFLOW
OVER THE N INTERIOR FRIDAY NIGHT THROUGH SUNDAY.

BOTH THE 12Z/18Z GFS AND 12Z ECMWF KEEP THE AREA DRY ON SUNDAY AS
WELL BUT RUN-TO-RUN CONSISTENCY IS NOT GOOD YET...SO CONFIDENCE IS
LOW. LOW CHANCE POPS ARE STILL IN THE FORECAST FOR BOTH SATURDAY AND
SUNDAY...BUT IF THE MODELS STICK WITH THIS SOLUTION SATURDAY AND
POSSIBLY EVEN SUNDAY COULD BE DRIED OUT AND SUNSHINE INCREASED. THE
COOL DRY FRASER RIVER VALLEY OUTFLOW AIR WILL LOWER SNOW LEVELS
CLOSE TO THE SURFACE...BUT MENTION OF SNOW HAS BEEN DROPPED FROM THE
FORECAST SINCE CONFIDENCE IS STILL LOW.

IF MODELS DO BRING PRECIP BACK OVER THE AREA THIS WEEKEND IT WILL
PROBABLY BE FROM AN UPPER LEVEL LOW W OF THE OREGON COAST SPREADING
WARM MOIST AIR NORTHWARD OVER THE AREA. KAM

&&

.HYDROLOGY...ONLY MINOR UPDATES TO PREVIOUS DISCUSSION...WRN WA
INCLUDING THE CASCADES WILL SEE A LULL IN RAINFALL THROUGH AT LEAST
MIDNIGHT. STRONG WARM ADVECTION WILL RE-DEVELOP LATE TONIGHT AND
TUESDAY MORNING...FOCUSED ON THE CENTRAL CASCADES FROM ABOUT
SNOQUALMIE PASS SOUTHWARD. THIS WILL AFFECT MAINLY THE PUYALLUP AND
COWLITZ RIVERS.

THE WARM FRONT WILL SHIFT SLOWLY N TUESDAY AFTERNOON AND NIGHT
SHIFTING THE HEAVIEST RAIN TO THE NORTH CASCADES. THIS WILL AFFECT
MULTIPLE RIVER BASINS INCLUDING THE SNOQUALMIE...STILLAGUAMISH...
SKAGIT...AND NOOKSACK.

THE WARM FRONT WILL LIKELY SHIFT OVER B.C. AROUND 12Z WEDNESDAY. THE
QPF FORECAST IS A BLEND OF THE MESOSCALE MODELS AND HAS 3 TO 4.5
INCHES SPREAD GENERALLY ACROSS THE CASCADES IN THE 48 HOUR PERIOD
ENDING 18Z WEDNESDAY. BULLSEYES OF 5 TO 7 INCHES ARE PRESENT OVER MT
BAKER AND MT RAINIER RESPECTIVELY. THERE IS STILL A LOT OF
UNCERTAINTY REGARDING THIS HEAVY RAIN EVENT...WITH INTENSITY OF THE
RAIN AND EXACTLY WHERE AND HOW LONG THE HEAVIEST PRECIP WILL FALL. A
FLOOD WATCH WAS ISSUED EARLIER THIS AFTERNOON COVERING THE CASCADES.

MODELS SHOW THE OLYMPICS GETTING LOWER AMOUNTS OF RAIN...BUT THERE
IS GREATER UNCERTAINTY WHETHER THIS W FLOW EVENT MIGHT DRIVE THE
BOGACHIEL RIVER TO FLOOD STAGE. THE EARLIER HYDROLOGIC OUTLOOK
COVERS THE HIGHER UNCERTAINTY OVER THE OLYMPICS.

AFTER THE WARM FRONT MOVES N ON WEDNESDAY MORNING THERE WILL BE A
SHORT LULL IN THE PRECIP. A WEAK COLD FRONT WILL MOVE THROUGH THE
AREA WEDNESDAY EVENING BRINGING A QUICK SHOT OF MODERATE RAIN.
ANOTHER BATCH OF WARM ADVECTION DEVELOPS BEHIND THE COLD FRONT FOR A
SECOND PERIOD OF MODERATE TO HEAVY RAIN FOR THE OLYMPICS AND N
CASCADES. KAM/MERCER

&&

.AVIATION...MODERATE WEST TO NORTHWEST FLOW ALOFT. A STATIONARY
FRONT WILL REMAIN OVER THE AREA THROUGH MIDDAY TUESDAY GIVING LOW
MVFR TO IFR CEILINGS AND VISIBILITIES IN RAIN TO MOST TERMINALS. THE
FRONT WILL START TO LIFT NORTHWARD AS A WARM FRONT LATE TUESDAY
AFTERNOON INTO TUESDAY NIGHT.

MODERATE LOW LEVEL SOUTHWEST FLOW OVER SOUTHERN PORTIONS OF THE AREA
TUESDAY MORNING WILL SPREAD NORTHWARD BEHIND THE WARM FRONT TUESDAY
AFTERNOON INTO TUESDAY NIGHT. A SLIGHT IMPROVEMENT TO
VISIBILITIES AND CEILINGS CAN BE EXPECTED LATE TUESDAY AFTERNOON AND
TUESDAY EVENING TO THE SOUTH OF THE WARM FRONT. ALBRECHT

KSEA...CIGS AROUND 015 TONIGHT WILL FALL TO 007-010 12Z THROUGH 22Z
TUE. SE WIND 7-10 KT WITH WIND SW 35 KT AT 020. ALBRECHT

&&

.MARINE...A NEARLY STATIONARY FRONT EXTENDS FROM THE CENTRAL PUGET
SOUND WESTWARD TO 140W. THE FRONT WILL REMAIN STATIONARY THROUGH
TUESDAY MORNING THEN WILL SLOWLY LIFT NORTH AS A WARM FRONT INTO
SOUTHERN BRITISH COLUMBIA TUESDAY NIGHT THROUGH WEDNESDAY. EXPECT
WINDS TO BECOME LIGHT LATE TONIGHT INTO TUESDAY MORNING. THEN SMALL
CRAFT ADVISORY SOUTHWEST WINDS 15 TO 30 KNOTS ARE EXPECTED TO SPREAD
NORTH THROUGH MOST OF THE WATERS MIDDAY TUESDAY THROUGH TUESDAY
NIGHT AS THE FRONT LIFTS NORTHWARD.

WINDY CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE FOR THE NEXT
SEVERAL DAYS. A COLD FRONT WILL SWEEP EASTWARD THROUGH THE WATERS
WEDNESDAY NIGHT OR THURSDAY. THIS FRONT WILL BE FOLLOWED BY ANOTHER
COLD FRONT THAT WILL DROP SOUTHWARD THROUGH THE WATERS ON FRIDAY.

STRONG OFFSHORE FLOW AND FRASER OUTFLOW ARE EXPECTED TO DEVELOP
LATER FRI INTO SAT AS COLD HIGH PRES MOVES INTO THE INTERIOR OF
BRITISH COLUMBIA. ALBRECHT

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES IN EFFECT FOR PORTIONS OF WESTERN WASHINGTON.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
















000
FXUS66 KSEW 250450
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
900 PM PST MON NOV 24 2014

.SYNOPSIS...A WARM FRONT WILL BRING RAIN...MILD TEMPERATURES AND
LOCALLY WINDY WEATHER TO WESTERN WASHINGTON THROUGH TUESDAY NIGHT. A
WEAK COLD FRONT WILL MOVE ACROSS THE AREA WEDNESDAY NIGHT. ANOTHER
WARM FRONT WILL BRING A LITTLE MORE RAIN ON THANKSGIVING. A COLD
FRONT WILL MOVE SLOWLY SOUTH ACROSS THE AREA FRIDAY AND FRIDAY
NIGHT. AN UPPER LEVEL RIDGE MAY BRING A COOLER DRIER PERIOD THIS
WEEKEND.

&&

.SHORT TERM...THE FIRST IN A SERIES OF SHORT WAVES RIDING OVER THE
TOP OF THE RIDGE CONTINUES TO PRODUCE RAIN ACROSS THE AREA. RAINFALL
TOTALS WITH THIS FIRST FEATURE HAVE SO FAR NOT BEEN ALL THAT
IMPRESSIVE WITH 1 TO LOCALLY 2 INCHES IN THE MOUNTAINS AND GENERALLY
LESS THAN A QUARTER INCH ACROSS THE LOWLANDS. RADAR SHOWS A RELATIVE
LULL IN RAINFALL WHICH WILL LIKELY CONTINUE UNTIL THE NEXT WAVE
REACHES THE AREA LATER TONIGHT.

MODELS ARE IN GOOD AGREEMENT THAT WARM ADVECTION RAINFALL
RE-DEVELOPS LATER TONIGHT INTO TUESDAY. RAIN AMOUNTS WITH THIS NEXT
FEATURE SHOULD BE A BIT MORE IMPRESSIVE...POSSIBLY 2-3 MORE INCHES
IN THE CASCADES AND UP TO 2 INCHES ALONG THE W SLOPES OF THE
OLYMPICS. THE LOWLANDS SHOULD ALSO HAVE SOME MODERATE RAIN AT
TIMES...ESPECIALLY DURING EARLY WHICH COULD IMPACT THE MORNING
COMMUTE. AMOUNTS OF A HALF INCH IN A FEW HOURS TIME COULD CAUSE SOME
TRAVEL DIFFICULTIES DUE TO PONDING OF WATER ON ROADWAYS. WILL NEED
TO MONITOR RAINFALL RATES IN THE LOWLANDS AS WELL AS THE MOUNTAINS.
OVERALL...THE NEWER 00Z MODELS ARE NOT SHOWING MUCH CHANGE IN THE
WET PATTERN THROUGH THURSDAY.

THE WARM FRONTAL WAVE PRODUCING LOCALLY HEAVY RAIN TUESDAY WILL LIFT
NWD BY WEDNESDAY. THIS WILL ALLOW FOR SOME REPRIEVE IN STEADY RAIN
ACROSS S/CENTRAL PORTIONS OF WRN WA. HOWEVER...THE MOISTURE BAND MAY
STILL PRODUCE RAIN AT TIMES ACROSS THE FAR N CASCADES AND POSSIBLY
THE OLYMPICS. ANY ADDITIONAL RAIN IN THESE AREAS WILL ONLY INCREASE
THE THREAT OF FLOODING ON RIVER BASINS AFFECTED BY STRONG WLY FLOW.
SEE THE HYDRO DISCUSSION FOR DETAILS.

THE ASSOCIATED COLD FRONT WILL FINALLY SWING INTO WRN WA ON
THURSDAY. STRONGER S/SW FLOW ALOFT WILL ADD TO RAIN AMOUNTS IN THE
SKOKOMISH RIVER BASIN WHICH WILL HEIGHTEN THE FLOOD RISK THERE.
WHILE THIS FRONT COULD TEMPORARILY WORSEN THE FLOOD
THREAT...PRECIPITATION WILL FINALLY EASE BEHIND THE FRONT FRIDAY
NIGHT. MERCER


.LONG TERM...NO UPDATES FROM PREVIOUS DISCUSSION...ON FRIDAY AND
FRIDAY NIGHT THE ECMWF AND GFS AGREE ON MOVING A COLD FRONT
SOUTHWARD ACROSS THE AREA. THIS FEATURE IS ACTUALLY THE LEFTOVER
OCCLUDED FRONT FROM THE MAIN LOW OFFSHORE. COOLER DRIER N FLOW ALOFT
AND AT LOW LEVELS WILL SPREAD S BEHIND THE FRONT FRIDAY NIGHT AND
SATURDAY MORNING AS AN UPPER LEVEL RIDGE BUILDS OFFSHORE AND A
SURFACE HIGH SHIFTS S OVER B.C.  COULD GET SOME BREEZY NE OUTFLOW
OVER THE N INTERIOR FRIDAY NIGHT THROUGH SUNDAY.

BOTH THE 12Z/18Z GFS AND 12Z ECMWF KEEP THE AREA DRY ON SUNDAY AS
WELL BUT RUN-TO-RUN CONSISTENCY IS NOT GOOD YET...SO CONFIDENCE IS
LOW. LOW CHANCE POPS ARE STILL IN THE FORECAST FOR BOTH SATURDAY AND
SUNDAY...BUT IF THE MODELS STICK WITH THIS SOLUTION SATURDAY AND
POSSIBLY EVEN SUNDAY COULD BE DRIED OUT AND SUNSHINE INCREASED. THE
COOL DRY FRASER RIVER VALLEY OUTFLOW AIR WILL LOWER SNOW LEVELS
CLOSE TO THE SURFACE...BUT MENTION OF SNOW HAS BEEN DROPPED FROM THE
FORECAST SINCE CONFIDENCE IS STILL LOW.

IF MODELS DO BRING PRECIP BACK OVER THE AREA THIS WEEKEND IT WILL
PROBABLY BE FROM AN UPPER LEVEL LOW W OF THE OREGON COAST SPREADING
WARM MOIST AIR NORTHWARD OVER THE AREA. KAM

&&

.HYDROLOGY...ONLY MINOR UPDATES TO PREVIOUS DISCUSSION...WRN WA
INCLUDING THE CASCADES WILL SEE A LULL IN RAINFALL THROUGH AT LEAST
MIDNIGHT. STRONG WARM ADVECTION WILL RE-DEVELOP LATE TONIGHT AND
TUESDAY MORNING...FOCUSED ON THE CENTRAL CASCADES FROM ABOUT
SNOQUALMIE PASS SOUTHWARD. THIS WILL AFFECT MAINLY THE PUYALLUP AND
COWLITZ RIVERS.

THE WARM FRONT WILL SHIFT SLOWLY N TUESDAY AFTERNOON AND NIGHT
SHIFTING THE HEAVIEST RAIN TO THE NORTH CASCADES. THIS WILL AFFECT
MULTIPLE RIVER BASINS INCLUDING THE SNOQUALMIE...STILLAGUAMISH...
SKAGIT...AND NOOKSACK.

THE WARM FRONT WILL LIKELY SHIFT OVER B.C. AROUND 12Z WEDNESDAY. THE
QPF FORECAST IS A BLEND OF THE MESOSCALE MODELS AND HAS 3 TO 4.5
INCHES SPREAD GENERALLY ACROSS THE CASCADES IN THE 48 HOUR PERIOD
ENDING 18Z WEDNESDAY. BULLSEYES OF 5 TO 7 INCHES ARE PRESENT OVER MT
BAKER AND MT RAINIER RESPECTIVELY. THERE IS STILL A LOT OF
UNCERTAINTY REGARDING THIS HEAVY RAIN EVENT...WITH INTENSITY OF THE
RAIN AND EXACTLY WHERE AND HOW LONG THE HEAVIEST PRECIP WILL FALL. A
FLOOD WATCH WAS ISSUED EARLIER THIS AFTERNOON COVERING THE CASCADES.

MODELS SHOW THE OLYMPICS GETTING LOWER AMOUNTS OF RAIN...BUT THERE
IS GREATER UNCERTAINTY WHETHER THIS W FLOW EVENT MIGHT DRIVE THE
BOGACHIEL RIVER TO FLOOD STAGE. THE EARLIER HYDROLOGIC OUTLOOK
COVERS THE HIGHER UNCERTAINTY OVER THE OLYMPICS.

AFTER THE WARM FRONT MOVES N ON WEDNESDAY MORNING THERE WILL BE A
SHORT LULL IN THE PRECIP. A WEAK COLD FRONT WILL MOVE THROUGH THE
AREA WEDNESDAY EVENING BRINGING A QUICK SHOT OF MODERATE RAIN.
ANOTHER BATCH OF WARM ADVECTION DEVELOPS BEHIND THE COLD FRONT FOR A
SECOND PERIOD OF MODERATE TO HEAVY RAIN FOR THE OLYMPICS AND N
CASCADES. KAM/MERCER

&&

.AVIATION...MODERATE WEST TO NORTHWEST FLOW ALOFT. A STATIONARY
FRONT WILL REMAIN OVER THE AREA THROUGH MIDDAY TUESDAY GIVING LOW
MVFR TO IFR CEILINGS AND VISIBILITIES IN RAIN TO MOST TERMINALS. THE
FRONT WILL START TO LIFT NORTHWARD AS A WARM FRONT LATE TUESDAY
AFTERNOON INTO TUESDAY NIGHT.

MODERATE LOW LEVEL SOUTHWEST FLOW OVER SOUTHERN PORTIONS OF THE AREA
TUESDAY MORNING WILL SPREAD NORTHWARD BEHIND THE WARM FRONT TUESDAY
AFTERNOON INTO TUESDAY NIGHT. A SLIGHT IMPROVEMENT TO
VISIBILITIES AND CEILINGS CAN BE EXPECTED LATE TUESDAY AFTERNOON AND
TUESDAY EVENING TO THE SOUTH OF THE WARM FRONT. ALBRECHT

KSEA...CIGS AROUND 015 TONIGHT WILL FALL TO 007-010 12Z THROUGH 22Z
TUE. SE WIND 7-10 KT WITH WIND SW 35 KT AT 020. ALBRECHT

&&

.MARINE...A NEARLY STATIONARY FRONT EXTENDS FROM THE CENTRAL PUGET
SOUND WESTWARD TO 140W. THE FRONT WILL REMAIN STATIONARY THROUGH
TUESDAY MORNING THEN WILL SLOWLY LIFT NORTH AS A WARM FRONT INTO
SOUTHERN BRITISH COLUMBIA TUESDAY NIGHT THROUGH WEDNESDAY. EXPECT
WINDS TO BECOME LIGHT LATE TONIGHT INTO TUESDAY MORNING. THEN SMALL
CRAFT ADVISORY SOUTHWEST WINDS 15 TO 30 KNOTS ARE EXPECTED TO SPREAD
NORTH THROUGH MOST OF THE WATERS MIDDAY TUESDAY THROUGH TUESDAY
NIGHT AS THE FRONT LIFTS NORTHWARD.

WINDY CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE FOR THE NEXT
SEVERAL DAYS. A COLD FRONT WILL SWEEP EASTWARD THROUGH THE WATERS
WEDNESDAY NIGHT OR THURSDAY. THIS FRONT WILL BE FOLLOWED BY ANOTHER
COLD FRONT THAT WILL DROP SOUTHWARD THROUGH THE WATERS ON FRIDAY.

STRONG OFFSHORE FLOW AND FRASER OUTFLOW ARE EXPECTED TO DEVELOP
LATER FRI INTO SAT AS COLD HIGH PRES MOVES INTO THE INTERIOR OF
BRITISH COLUMBIA. ALBRECHT

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCHES IN EFFECT FOR PORTIONS OF WESTERN WASHINGTON.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML















000
FXUS66 KSEW 242359
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
400 PM PST MON NOV 24 2014

.SYNOPSIS...A WARM FRONT WILL SPREAD RAIN ACROSS WESTERN WASHINGTON
THROUGH THIS EVENING...THEN SETTLE OVER WESTERN WASHINGTON TONIGHT
THROUGH WEDNESDAY MORNING ALLOWING RAIN...MILD TEMPERATURES AND
OCCASIONALLY WINDY WEATHER TO CONTINUE. A WEAK COLD FRONT WILL MOVE
ACROSS THE AREA WEDNESDAY NIGHT. ANOTHER WARM FRONT WILL BRING A
LITTLE MORE RAIN ON THANKSGIVING. A COLD FRONT WILL MOVE SLOWLY
SOUTH ACROSS THE AREA FRIDAY AND FRIDAY NIGHT. AN UPPER LEVEL RIDGE
MAY BRING A COOLER DRIER PERIOD THIS WEEKEND.

&&

.SHORT TERM...A BROAD LOW AMPLITUDE RIDGE IS IN PLACE OFFSHORE WITH
THE AXIS ALONG ROUGHLY 130W. MODELS AND IR IMAGERY SHOW HEALTHY WARM
ADVECTION MOVING THROUGH THE RIDGE WHICH HAS SPREAD RAIN INLAND OVER
W WA THIS AFTERNOON. COASTAL RADAR SHOWS A BACK EDGE TO THE PRECIP
OFFSHORE WHICH SHOULD BE THE INITIAL WARM FRONT. STRONG LOW LEVEL W
FLOW ALOFT WITH HEALTHY WARM ADVECTION WILL CONTINUE LATE TONIGHT
AND TUESDAY MORNING...FOCUSED MORE ON THE SOUTH HALF OF THE AREA.
THIS WILL RESULT IN HEAVY RAIN OVER THE CENTRAL CASCADES FROM ABOUT
SNOQUALMIE PASS SOUTHWARD. THE OFFSHORE RIDGE WILL BUILD TUESDAY
AFTERNOON AND TUESDAY NIGHT WHICH WILL SLOWLY SHIFT THE MAIN WARM
ADVECTION AREA OVER THE N CASCADES. THE QPF FORECAST IS A BLEND OF
THE MESOSCALE MODELS AND DROPS 3 TO 4.5 INCHES OVER MUCH OF THE
CASCADES...WITH BULLSEYES OF 5-7 INCHES OVER MT BAKER AND MT
RAINIER...OVER THE 48 HOUR PERIOD FROM 18Z TODAY THROUGH 18Z
WEDNESDAY. THAT MAY BE ENOUGH FOR SOME OF THE RIVERS FLOWING OFF THE
CASCADES TO REACH FLOOD STAGE...SO A FLOOD WATCH WAS ISSUED EARLIER
THIS AFTERNOON. OVER THE LOWLANDS RAINFALL AMOUNTS WILL PROBABLY END
UP RANGING FROM ABOUT A THIRD OF AN INCH TO A LITTLE OVER AN INCH.
THE GREATER PUGET SOUND REGION WILL PROBABLY BE PARTIALLY SHADOWED
BY THE OLYMPICS IN THIS W FLOW PATTERN.

ONCE THE WARM FRONT MOVES N OVER B.C. WEDNESDAY MORNING THERE WILL
BE A LULL IN PRECIP OVER THE AREA. THE MOIST AIR MASS COULD STILL
DROP A LITTLE LIGHT RAIN...SO POPS ARE IN THE CHANCE RANGE. A WEAK
COLD FRONT WILL MOVE E ACROSS THE AREA WEDNESDAY EVENING...BRINGING
A LITTLE MORE LIGHT RAIN TO MAINLY THE MOUNTAINS.

W FLOW ALOFT WILL INCREASE AGAIN BEHIND THE COLD FRONT AS ANOTHER
BATCH OF WARM ADVECTION MOVES OVER THE AREA. THIS LOOKS LIKE IT
BRING ANOTHER ROUND OF MODERATE TO HEAVY RAIN TO THE OLYMPICS AND N
CASCADES THURSDAY THROUGH THURSDAY EVENING.

INCREASING SOUTHERLY SURFACE FLOW BEHIND TUESDAYS WARM FRONT WILL
BRING BREEZY TO WINDY CONDITIONS TO MANY AREAS THROUGH WEDNESDAY.
BREEZY SE WINDS WILL DEVELOP WEDNESDAY NIGHT AND THURSDAY ASSOCIATED
WITH THE COLD FRONT. ALL THE WARM ADVECTION WILL KEEP TEMPERATURES
RATHER MILD...WITH LOWS IN THE 45-50 RANGE AND HIGHS IN THE MID TO
UPPER 50S. KAM

.LONG TERM...ON FRIDAY AND FRIDAY NIGHT THE ECMWF AND GFS AGREE ON
MOVING A COLD FRONT SOUTHWARD ACROSS THE AREA. THIS FEATURE IS
ACTUALLY THE LEFTOVER OCCLUDED FRONT FROM THE MAIN LOW OFFSHORE.
COOLER DRIER N FLOW ALOFT AND AT LOW LEVELS WILL SPREAD S BEHIND THE
FRONT FRIDAY NIGHT AND SATURDAY MORNING AS AN UPPER LEVEL RIDGE
BUILDS OFFSHORE AND A SURFACE HIGH SHIFTS S OVER B.C.  COULD GET
SOME BREEZY NE OUTFLOW OVER THE N INTERIOR FRIDAY NIGHT THROUGH
SUNDAY.

BOTH THE 12Z/18Z GFS AND 12Z ECMWF KEEP THE AREA DRY ON SUNDAY AS
WELL BUT RUN-TO-RUN CONSISTENCY IS NOT GOOD YET...SO CONFIDENCE IS
LOW. LOW CHANCE POPS ARE STILL IN THE FORECAST FOR BOTH SATURDAY AND
SUNDAY...BUT IF THE MODELS STICK WITH THIS SOLUTION SATURDAY AND
POSSIBLY EVEN SUNDAY COULD BE DRIED OUT AND SUNSHINE INCREASED. THE
COOL DRY FRASER RIVER VALLEY OUTFLOW AIR WILL LOWER SNOW LEVELS
CLOSE TO THE SURFACE...BUT MENTION OF SNOW HAS BEEN DROPPED FROM THE
FORECAST SINCE CONFIDENCE IS STILL LOW.

IF MODELS DO BRING PRECIP BACK OVER THE AREA THIS WEEKEND IT WILL
PROBABLY BE FROM AN UPPER LEVEL LOW W OF THE OREGON COAST SPREADING
WARM MOIST AIR NORTHWARD OVER THE AREA. KAM

&&

.HYDROLOGY...STRONG WARM ADVECTION COMING THROUGH THE BROAD FLAT
UPPER LEVEL RIDGE OFFSHORE WILL BRING HEAVY RAIN AT TIMES TO THE
CASCADES TONIGHT THROUGH TUESDAY NIGHT. THE WHOLE CASCADES WILL GET
A BRIEF SHOT OF RAIN THIS EVENING FROM AN INITIAL WARM FRONT MOVING
THROUGH THE AREA. STRONG WARM ADVECTION WILL RE-DEVELOP LATE TONIGHT
AND TUESDAY MORNING...FOCUSED ON THE CENTRAL CASCADES FROM ABOUT
SNOQUALMIE PASS SOUTHWARD. THIS WILL AFFECT MAINLY THE PUYALLUP AND
COWLITZ RIVERS.

THE WARM FRONT WILL SHIFT SLOWLY N TUESDAY AFTERNOON AND NIGHT
SHIFTING THE HEAVIEST RAIN TO THE NORTH CASCADES. THIS WILL AFFECT
MULTIPLE RIVER BASINS INCLUDING THE SNOQUALMIE...STILLAGUAMISH...
SKAGIT...AND NOOKSACK.

THE WARM FRONT WILL LIKELY SHIFT OVER B.C. AROUND 12Z WEDNESDAY. THE
QPF FORECAST IS A BLEND OF THE MESOSCALE MODELS AND HAS 3 TO 4.5
INCHES SPREAD GENERALLY ACROSS THE CASCADES IN THE 48 HOUR PERIOD
ENDING 18Z WEDNESDAY. BULLSEYES OF 5 TO 7 INCHES ARE PRESENT OVER MT
BAKER AND MT RAINIER RESPECTIVELY. THERE IS STILL A LOT OF
UNCERTAINTY REGARDING THIS HEAVY RAIN EVENT...WITH INTENSITY OF THE
RAIN AND EXACTLY WHERE AND HOW LONG THE HEAVIEST PRECIP WILL FALL. A
FLOOD WATCH WAS ISSUED EARLIER THIS AFTERNOON COVERING THE CASCADES.

MODELS SHOW THE OLYMPICS GETTING LOWER AMOUNTS OF RAIN...BUT THERE
IS GREATER UNCERTAINTY WHETHER THIS W FLOW EVENT MIGHT DRIVE THE
BOGACHIEL RIVER TO FLOOD STAGE. THE EARLIER HYDROLOGIC OUTLOOK
COVERS THE HIGHER UNCERTAINTY OVER THE OLYMPICS.

AFTER THE WARM FRONT MOVES N ON WEDNESDAY MORNING THERE WILL BE A
SHORT LULL IN THE PRECIP. A WEAK COLD FRONT WILL MOVE THROUGH THE
AREA WEDNESDAY EVENING BRINGING A QUICK SHOT OF MODERATE RAIN.
ANOTHER BATCH OF WARM ADVECTION DEVELOPS BEHIND THE COLD FRONT FOR A
SECOND PERIOD OF MODERATE TO HEAVY RAIN FOR THE OLYMPICS AND N
CASCADES. KAM

&&

.AVIATION...MODERATE NORTHWESTERLY FLOW ALOFT WILL CONTINUE TONIGHT
AND TUESDAY. A WARM FRONT WILL REMAIN OVER THE AREA THROUGH TUESDAY.
MODERATE SOUTHERLY GRADIENTS WILL GIVE BREEZY TO WINDY CONDITIONS AT
TIMES.

CONDITIONS ARE MAINLY VFR THIS AFTERNOON EXCEPT FOR SOME MVFR
CEILINGS OVER THE NORTH INTERIOR. CLOUDS WILL CONTINUE TO THICKEN
AND LOWER THIS EVENING GIVING 3-5K FT CEILINGS THEN MVFR 1-2K FT
CEILINGS TONIGHT AS RAIN INCREASES.

KSEA...DISCUSSION ABOVE APPLIES. SOUTHEAST WIND 5-8 KT WILL BECOME
SOUTHERLY AND INCREASE TO S10G20 KT TONIGHT. CHB

&&

.MARINE...SOUTHERLY WINDS OF 15-30 KT ARE LIKELY OVER MOST WATERS
TONIGHT AS A WARM FRONT MOVES OVER THE AREA. THE WARM FRONT IS
FORECAST TO MOVE NORTH INTO SOUTHERN BRITISH COLUMBIA TUESDAY
AFTERNOON AND EVENING. SMALL CRAFT ADVISORIES ARE IN EFFECT OVER ALL
WATERS INCLUDING THE CENTRAL STRAIT WHERE A BRIEF WESTERLY PUSH IS
LIKELY THIS EVENING BEHIND THE WARM FRONT.

ANOTHER FRONT WILL ARRIVE THURSDAY FOR ANOTHER ROUND OF SOUTHERLY
WINDS. ON FRIDAY A COLD HIGH PRES SYSTEM WILL DEVELOP OVER THE
INTERIOR OF BRITISH COLUMBIA. BY LATER FRIDAY INTO THE WEEKEND
STRONG NORTHEAST FLOW IS POSSIBLE OVER THE AREA WITH FRASER OUTFLOW
OVER THE NORTHERN INLAND WATERS. CHB

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCH FOR COUNTIES WITH RIVERS FLOWING OFF THE CASCADES.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML













000
FXUS66 KSEW 242359
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
400 PM PST MON NOV 24 2014

.SYNOPSIS...A WARM FRONT WILL SPREAD RAIN ACROSS WESTERN WASHINGTON
THROUGH THIS EVENING...THEN SETTLE OVER WESTERN WASHINGTON TONIGHT
THROUGH WEDNESDAY MORNING ALLOWING RAIN...MILD TEMPERATURES AND
OCCASIONALLY WINDY WEATHER TO CONTINUE. A WEAK COLD FRONT WILL MOVE
ACROSS THE AREA WEDNESDAY NIGHT. ANOTHER WARM FRONT WILL BRING A
LITTLE MORE RAIN ON THANKSGIVING. A COLD FRONT WILL MOVE SLOWLY
SOUTH ACROSS THE AREA FRIDAY AND FRIDAY NIGHT. AN UPPER LEVEL RIDGE
MAY BRING A COOLER DRIER PERIOD THIS WEEKEND.

&&

.SHORT TERM...A BROAD LOW AMPLITUDE RIDGE IS IN PLACE OFFSHORE WITH
THE AXIS ALONG ROUGHLY 130W. MODELS AND IR IMAGERY SHOW HEALTHY WARM
ADVECTION MOVING THROUGH THE RIDGE WHICH HAS SPREAD RAIN INLAND OVER
W WA THIS AFTERNOON. COASTAL RADAR SHOWS A BACK EDGE TO THE PRECIP
OFFSHORE WHICH SHOULD BE THE INITIAL WARM FRONT. STRONG LOW LEVEL W
FLOW ALOFT WITH HEALTHY WARM ADVECTION WILL CONTINUE LATE TONIGHT
AND TUESDAY MORNING...FOCUSED MORE ON THE SOUTH HALF OF THE AREA.
THIS WILL RESULT IN HEAVY RAIN OVER THE CENTRAL CASCADES FROM ABOUT
SNOQUALMIE PASS SOUTHWARD. THE OFFSHORE RIDGE WILL BUILD TUESDAY
AFTERNOON AND TUESDAY NIGHT WHICH WILL SLOWLY SHIFT THE MAIN WARM
ADVECTION AREA OVER THE N CASCADES. THE QPF FORECAST IS A BLEND OF
THE MESOSCALE MODELS AND DROPS 3 TO 4.5 INCHES OVER MUCH OF THE
CASCADES...WITH BULLSEYES OF 5-7 INCHES OVER MT BAKER AND MT
RAINIER...OVER THE 48 HOUR PERIOD FROM 18Z TODAY THROUGH 18Z
WEDNESDAY. THAT MAY BE ENOUGH FOR SOME OF THE RIVERS FLOWING OFF THE
CASCADES TO REACH FLOOD STAGE...SO A FLOOD WATCH WAS ISSUED EARLIER
THIS AFTERNOON. OVER THE LOWLANDS RAINFALL AMOUNTS WILL PROBABLY END
UP RANGING FROM ABOUT A THIRD OF AN INCH TO A LITTLE OVER AN INCH.
THE GREATER PUGET SOUND REGION WILL PROBABLY BE PARTIALLY SHADOWED
BY THE OLYMPICS IN THIS W FLOW PATTERN.

ONCE THE WARM FRONT MOVES N OVER B.C. WEDNESDAY MORNING THERE WILL
BE A LULL IN PRECIP OVER THE AREA. THE MOIST AIR MASS COULD STILL
DROP A LITTLE LIGHT RAIN...SO POPS ARE IN THE CHANCE RANGE. A WEAK
COLD FRONT WILL MOVE E ACROSS THE AREA WEDNESDAY EVENING...BRINGING
A LITTLE MORE LIGHT RAIN TO MAINLY THE MOUNTAINS.

W FLOW ALOFT WILL INCREASE AGAIN BEHIND THE COLD FRONT AS ANOTHER
BATCH OF WARM ADVECTION MOVES OVER THE AREA. THIS LOOKS LIKE IT
BRING ANOTHER ROUND OF MODERATE TO HEAVY RAIN TO THE OLYMPICS AND N
CASCADES THURSDAY THROUGH THURSDAY EVENING.

INCREASING SOUTHERLY SURFACE FLOW BEHIND TUESDAYS WARM FRONT WILL
BRING BREEZY TO WINDY CONDITIONS TO MANY AREAS THROUGH WEDNESDAY.
BREEZY SE WINDS WILL DEVELOP WEDNESDAY NIGHT AND THURSDAY ASSOCIATED
WITH THE COLD FRONT. ALL THE WARM ADVECTION WILL KEEP TEMPERATURES
RATHER MILD...WITH LOWS IN THE 45-50 RANGE AND HIGHS IN THE MID TO
UPPER 50S. KAM

.LONG TERM...ON FRIDAY AND FRIDAY NIGHT THE ECMWF AND GFS AGREE ON
MOVING A COLD FRONT SOUTHWARD ACROSS THE AREA. THIS FEATURE IS
ACTUALLY THE LEFTOVER OCCLUDED FRONT FROM THE MAIN LOW OFFSHORE.
COOLER DRIER N FLOW ALOFT AND AT LOW LEVELS WILL SPREAD S BEHIND THE
FRONT FRIDAY NIGHT AND SATURDAY MORNING AS AN UPPER LEVEL RIDGE
BUILDS OFFSHORE AND A SURFACE HIGH SHIFTS S OVER B.C.  COULD GET
SOME BREEZY NE OUTFLOW OVER THE N INTERIOR FRIDAY NIGHT THROUGH
SUNDAY.

BOTH THE 12Z/18Z GFS AND 12Z ECMWF KEEP THE AREA DRY ON SUNDAY AS
WELL BUT RUN-TO-RUN CONSISTENCY IS NOT GOOD YET...SO CONFIDENCE IS
LOW. LOW CHANCE POPS ARE STILL IN THE FORECAST FOR BOTH SATURDAY AND
SUNDAY...BUT IF THE MODELS STICK WITH THIS SOLUTION SATURDAY AND
POSSIBLY EVEN SUNDAY COULD BE DRIED OUT AND SUNSHINE INCREASED. THE
COOL DRY FRASER RIVER VALLEY OUTFLOW AIR WILL LOWER SNOW LEVELS
CLOSE TO THE SURFACE...BUT MENTION OF SNOW HAS BEEN DROPPED FROM THE
FORECAST SINCE CONFIDENCE IS STILL LOW.

IF MODELS DO BRING PRECIP BACK OVER THE AREA THIS WEEKEND IT WILL
PROBABLY BE FROM AN UPPER LEVEL LOW W OF THE OREGON COAST SPREADING
WARM MOIST AIR NORTHWARD OVER THE AREA. KAM

&&

.HYDROLOGY...STRONG WARM ADVECTION COMING THROUGH THE BROAD FLAT
UPPER LEVEL RIDGE OFFSHORE WILL BRING HEAVY RAIN AT TIMES TO THE
CASCADES TONIGHT THROUGH TUESDAY NIGHT. THE WHOLE CASCADES WILL GET
A BRIEF SHOT OF RAIN THIS EVENING FROM AN INITIAL WARM FRONT MOVING
THROUGH THE AREA. STRONG WARM ADVECTION WILL RE-DEVELOP LATE TONIGHT
AND TUESDAY MORNING...FOCUSED ON THE CENTRAL CASCADES FROM ABOUT
SNOQUALMIE PASS SOUTHWARD. THIS WILL AFFECT MAINLY THE PUYALLUP AND
COWLITZ RIVERS.

THE WARM FRONT WILL SHIFT SLOWLY N TUESDAY AFTERNOON AND NIGHT
SHIFTING THE HEAVIEST RAIN TO THE NORTH CASCADES. THIS WILL AFFECT
MULTIPLE RIVER BASINS INCLUDING THE SNOQUALMIE...STILLAGUAMISH...
SKAGIT...AND NOOKSACK.

THE WARM FRONT WILL LIKELY SHIFT OVER B.C. AROUND 12Z WEDNESDAY. THE
QPF FORECAST IS A BLEND OF THE MESOSCALE MODELS AND HAS 3 TO 4.5
INCHES SPREAD GENERALLY ACROSS THE CASCADES IN THE 48 HOUR PERIOD
ENDING 18Z WEDNESDAY. BULLSEYES OF 5 TO 7 INCHES ARE PRESENT OVER MT
BAKER AND MT RAINIER RESPECTIVELY. THERE IS STILL A LOT OF
UNCERTAINTY REGARDING THIS HEAVY RAIN EVENT...WITH INTENSITY OF THE
RAIN AND EXACTLY WHERE AND HOW LONG THE HEAVIEST PRECIP WILL FALL. A
FLOOD WATCH WAS ISSUED EARLIER THIS AFTERNOON COVERING THE CASCADES.

MODELS SHOW THE OLYMPICS GETTING LOWER AMOUNTS OF RAIN...BUT THERE
IS GREATER UNCERTAINTY WHETHER THIS W FLOW EVENT MIGHT DRIVE THE
BOGACHIEL RIVER TO FLOOD STAGE. THE EARLIER HYDROLOGIC OUTLOOK
COVERS THE HIGHER UNCERTAINTY OVER THE OLYMPICS.

AFTER THE WARM FRONT MOVES N ON WEDNESDAY MORNING THERE WILL BE A
SHORT LULL IN THE PRECIP. A WEAK COLD FRONT WILL MOVE THROUGH THE
AREA WEDNESDAY EVENING BRINGING A QUICK SHOT OF MODERATE RAIN.
ANOTHER BATCH OF WARM ADVECTION DEVELOPS BEHIND THE COLD FRONT FOR A
SECOND PERIOD OF MODERATE TO HEAVY RAIN FOR THE OLYMPICS AND N
CASCADES. KAM

&&

.AVIATION...MODERATE NORTHWESTERLY FLOW ALOFT WILL CONTINUE TONIGHT
AND TUESDAY. A WARM FRONT WILL REMAIN OVER THE AREA THROUGH TUESDAY.
MODERATE SOUTHERLY GRADIENTS WILL GIVE BREEZY TO WINDY CONDITIONS AT
TIMES.

CONDITIONS ARE MAINLY VFR THIS AFTERNOON EXCEPT FOR SOME MVFR
CEILINGS OVER THE NORTH INTERIOR. CLOUDS WILL CONTINUE TO THICKEN
AND LOWER THIS EVENING GIVING 3-5K FT CEILINGS THEN MVFR 1-2K FT
CEILINGS TONIGHT AS RAIN INCREASES.

KSEA...DISCUSSION ABOVE APPLIES. SOUTHEAST WIND 5-8 KT WILL BECOME
SOUTHERLY AND INCREASE TO S10G20 KT TONIGHT. CHB

&&

.MARINE...SOUTHERLY WINDS OF 15-30 KT ARE LIKELY OVER MOST WATERS
TONIGHT AS A WARM FRONT MOVES OVER THE AREA. THE WARM FRONT IS
FORECAST TO MOVE NORTH INTO SOUTHERN BRITISH COLUMBIA TUESDAY
AFTERNOON AND EVENING. SMALL CRAFT ADVISORIES ARE IN EFFECT OVER ALL
WATERS INCLUDING THE CENTRAL STRAIT WHERE A BRIEF WESTERLY PUSH IS
LIKELY THIS EVENING BEHIND THE WARM FRONT.

ANOTHER FRONT WILL ARRIVE THURSDAY FOR ANOTHER ROUND OF SOUTHERLY
WINDS. ON FRIDAY A COLD HIGH PRES SYSTEM WILL DEVELOP OVER THE
INTERIOR OF BRITISH COLUMBIA. BY LATER FRIDAY INTO THE WEEKEND
STRONG NORTHEAST FLOW IS POSSIBLE OVER THE AREA WITH FRASER OUTFLOW
OVER THE NORTHERN INLAND WATERS. CHB

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WATCH FOR COUNTIES WITH RIVERS FLOWING OFF THE CASCADES.
PZ...SMALL CRAFT ADVISORY ALL WATERS.
     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.

&&

$$

YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML












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