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000
FXUS66 KSEW 250418
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
920 PM PDT FRI OCT 24 2014

.SYNOPSIS...RAIN WILL SPREAD FROM SOUTH TO NORTH TONIGHT. A FILLING
LOW PRESSURE CENTER WILL MOVE ACROSS THE AREA SATURDAY NIGHT...
BRINGING RAIN AND LOCALLY WINDY CONDITIONS. SUNDAY AND MONDAY WILL
BE SHOWERY. WET AND BREEZY WEATHER ARE LIKELY AT TIMES NEXT WEEK.

&&

.SHORT TERM...A WARM FRONT WILL LIFT NORTH THROUGH THE REGION
TONIGHT. RAIN HAS ALREADY SPREAD AS FAR NORTH AS NORTHERN PUGET
SOUND AND SHOULD FILL IN OVER THE REMAINDER OF THE NORTHWEST
INTERIOR IN THE NEXT FEW HOURS. MESO MODELS SHOW A FAIRLY DISTINCT
BACK EDGE TO THE RAINS LATER TONIGHT AND IT LOOKS LIKE THE SOUTH
INTERIOR WILL SEE RAIN ENDING SOMETIME IN THE EARLY MORNING HOURS OR
EVEN LATE THIS EVENING. THERE SHOULD ALSO BE SOME GUSTY EAST WINDS
OVER THE EAST PUGET SOUND LOWLANDS THROUGH SATURDAY MORNING WITH
INCREASING EASTERLY GRADIENTS AHEAD OF THE FRONTAL SYSTEM.

A COLD FRONT WILL MOVE ONSHORE ON SATURDAY. AREAS WHERE RAIN TAPERS
LATER TONIGHT OR EARLY SATURDAY MORNING SHOULD SEE RAIN REDEVELOP
DURING THE DAY. THE CURRENT CHANCE OF RAIN FORECAST FOR PARTS OF THE
INTERIOR ON SATURDAY MIGHT BE TOO OPTIMISTIC.

A FILLING SURFACE LOW WILL MOVE ONSHORE NEAR THE CENTRAL WASHINGTON
COAST IN THE AFTERNOON AND TRACK NORTHEAST ACROSS WESTERN WASHINGTON
DURING THE EVENING. BREEZY TO WINDY SOUTH TO WEST WINDS ARE LIKELY
BEHIND THE LOW IN THE EVENING. THIS LOOKS LIKE A BLUSTERY PATTERN
FOR THE SEATTLE AREA.

SHOWERS WILL LINGER INTO SUNDAY BEHIND THE FRONT BUT THE TREND
SHOULD BE FOR DECREASING PRECIPITATION AS WEAK HIGH PRESSURE ALOFT
BUILDS IN. IT LOOKS FAIRLY DRY MOST AREAS BY SUNDAY NIGHT BUT
PRECIPITATION CHANCES WILL BE INCREASING AGAIN ON MONDAY AS ANOTHER
FRONTAL SYSTEM APPROACHES FROM THE WEST. SCHNEIDER

.LONG TERM...PREVIOUS DISCUSSION...MODELS AGREE THE NEXT SYSTEM WILL
BE NEARING THE COAST MONDAY NIGHT. THERE IS A DEEP LOW ASSOCIATED
WITH THIS SYSTEM THAT IS FORECAST TO CROSS NORTHERN VANCOUVER ISLAND
TUESDAY. SOUTHEAST GRADIENTS WILL BE STRONG ACROSS WESTERN
WASHINGTON BUT WITH THIS PATTERN THERE IS USUALLY NO HIGH WIND.
AFTER RAIN TUESDAY...SHOWERS FOLLOW ON WEDNESDAY AND THURSDAY.
ANOTHER SYSTEM MAY ARRIVE AROUND NEXT FRIDAY. TEMPERATURES NEXT WEEK
WILL BE NEAR SEASONAL NORMS WITH HIGHS IN THE 50S AND LOWS IN THE
40S. BURKE

&&

.HYDROLOGY...THE SKOKOMISH RIVER WILL RISE AGAIN IN RESPONSE TO
HEAVY RAIN TONIGHT AND SATURDAY. SINCE IT IS STILL RUNNING HIGH FROM
THE PREVIOUS EVENT...IT IS POSSIBLE THE RIVER WILL GET CLOSE TO
FLOOD STAGE ON SATURDAY. FOR NOW THE FORECAST TAKES THE STAGE AT
POTLATCH TO BETWEEN 15.5 AND 16 FEET. FLOOD STAGE IS 16.5 FEET. ON
OTHER RIVERS FLOODING IS UNLIKELY OVER THE NEXT 7 DAYS.

&&

.AVIATION...MOIST SOUTHWEST FLOW ALOFT WILL CONTINUE OVER W WA AS A
WARM FRONT MOVES N ACROSS W WA THROUGH 12Z. CIGS ARE EXPECTED TO
LOWER TO MVFR LEVELS...WITH SPOTTY IFR CONDITIONS...AS THE RAIN
MOISTENS THE LOWER AIR MASS. A COLD FRONT WILL MOVE INLAND ACROSS W
WA SATURDAY MORNING. THE MAIN UPPER LEVEL AND SURFACE LOW WILL
FOLLOW SATURDAY AFTERNOON AND NIGHT. MVFR CIGS ARE EXPECTED TO
PREDOMINATE THROUGH SATURDAY NIGHT.

KSEA...WARM FRONT RAIN HAS REACHED KSEA AND CIGS WILL GRADUALLY
LOWER AS THE RAIN MOISTENS THE LOWER AIR MASS. CIGS WILL REMAIN VFR
THROUGH 07Z AND SHOULD LOWER TO MVFR LEVELS AFTER 12Z. CONDITIONS
WILL LIKELY DETERIORATE TO LOW-END MVFR AND PERHAPS OCCASIONAL IFR
IN RAIN AND FOG SATURDAY MORNING. SURFACE WINDS WILL BE N-NE 4-10KT
THROUGH 12Z. A SHIFT TO S WINDS WILL PROBABLY OCCUR AROUND 15Z OR
SO. KAM

&&

.MARINE...A WARM FRONT WILL MOVE NORTH ACROSS THE AREA TONIGHT. THE
VARIOUS MODELS HAVE NOT BEEN IN COMPLETE AGREEMENT WITH THE
EVOLUTION OF THIS SYSTEM INCLUDING THE STRUCTURE AND TRACK OF THE
SURFACE LOW OR LOWS. THEY HAVE LEANED TOWARD A SOLUTION THAT MOST OF
THE MESOSCALE MODELS HAVE AND WHICH IS SIMILAR TO 12Z ECMWF. THIS
BRINGS ABOUT A 994 MB SURFACE LOW NE ACROSS THE COASTAL WATERS ON
SATURDAY. THIS LOW IS ASSOCIATED WITH THE TRAILING COLD FRONT. NEW
00Z NAM AND HRRR INDICATE AREAS OF GALE FORCE WINDS SPREADING N
ACROSS THE SOUTHERN FOUR COASTAL ZONES LATE TONIGHT...THEN
CONTINUING OFF AND ON THROUGH EARLY SATURDAY AFTERNOON. THE 00Z NAM
AND 12Z ECMWF THEN BRING A SECOND SURFACE LOW ASSOCIATED WITH MAIN
UPPER LEVEL LOW NE ACROSS ASTORIA AROUND 00Z SUNDAY/5 PM SATURDAY
THEN CONTINUING N-NE TOWARD EITHER N CENTRAL WA OR THE N INTERIOR
EARLY SATURDAY EVENING. THIS TRACK HAS THE POTENTIAL FOR SCA OR
BETTER WINDS OVER THE INTERIOR WATERS. CONFIDENCE IS LOW HERE BASED
ON THE UNCERTAIN TRACK OF THE SECOND LOW.

HIGH PRESSURE WILL BUILD OVER THE REGION SUNDAY AND BEGIN TO MOVE
EAST OF THE AREA MONDAY. ANOTHER VIGOROUS FRONTAL SYSTEM WILL AFFECT
THE AREA MONDAY NIGHT AND TUESDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...WIND ADVISORY FOR THE EAST PUGET SOUND LOWLANDS TONIGHT THROUGH
     SATURDAY MORNING.
     WIND ADVISORY FOR BELLEVUE AND VICINITY TONIGHT.
PZ...GALE WARNING SOUTHERN FOUR COASTAL ZONES.
     SMALL CRAFT ADVISORY NORTHERN TWO COASTAL ZONES AND WEST
      ENTRANCE OF THE STRAIT.

&&

$$

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










000
FXUS66 KSEW 242154
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
300 PM PDT FRI OCT 24 2014

.SYNOPSIS...RAIN WILL SPREAD FROM SOUTH TO NORTH TONIGHT. A FILLING
LOW PRESSURE CENTER WILL MOVE ACROSS THE AREA SATURDAY NIGHT...
BRINGING RAIN AND LOCALLY WINDY CONDITIONS. SUNDAY AND MONDAY WILL
BE SHOWERY. WET AND BREEZY WEATHER ARE LIKELY AT TIMES NEXT WEEK.

&&

.SHORT TERM...A DEEP LOW CENTER WELL OFF THE NORTHERN CALIFORNIA
COAST WILL MOVE NORTHEAST TONIGHT AND WEAKEN AS IT MOVES ONTO THE
WASHINGTON COAST SATURDAY AFTERNOON. THE LOW WILL MOVE ACROSS
WESTERN WASHINGTON SATURDAY NIGHT AND BE OUT OF THE AREA SUNDAY.

THE FIRST FEATURE ASSOCIATED WITH THIS SYSTEM IS A WEAK WARM FRONT
THAT WILL MOVE FROM SOUTH TO NORTH ACROSS WASHINGTON TONIGHT. THIS
WILL SPREAD RAIN OVER THE AREA. AMOUNTS EAST OF PUGET SOUND ARE
LIKELY TO BE LIGHT AS STRONG EASTERLY WINDS BEGIN IN RESPONSE TO
EASTERLY GRADIENTS. MODELS DO SHOW A FAIR AMOUNT OF RAIN OVER THE
OLYMPICS AND COAST...SPREADING INTO THE FAR NORTHERN INTERIOR
SATURDAY MORNING. A WIND ADVISORY IS IN EFFECT TONIGHT FOR THE EAST
PUGET SOUND LOWLANDS AND THE BELLEVUE AREA.

THE SECOND FEATURE IS THE STRONG ONSHORE GRADIENTS THAT FOLLOW THE
PASSAGE OF THE LOW CENTER SATURDAY NIGHT. THESE ARE LIKELY TO BRING
BREEZY TO WINDY CONDITIONS TO MOST AREAS. AT THIS TIME THERE DOES
NOT APPEAR TO BE A THREAT OF HIGH WIND.

THE FINAL FEATURE IS THE 18 HOURS OR SO OF HEAVY RAIN OVER THE
OLYMPICS...FROM 06Z TONIGHT TO 00Z SUNDAY. THE RAINIER PARTS WILL
GET 2-3 INCHES...WITH MOST OF THE OLYMPIC PENINSULA GETTING AN INCH
OR MORE. RAIN WILL DIMINISH CONSIDERABLY SATURDAY NIGHT...FIRST IN
THE OLYMPICS AND THEN IN THE CASCADES.

THE WEATHER WILL BE MORE SHOWERY SUNDAY AND MONDAY WITH LIKELY POPS
ON THE COAST AND IN THE MOUNTAINS...CHANCE POPS OVER THE INTERIOR
LOWLANDS. HIGHS WILL NOT VARY MUCH...55-60 ON SATURDAY FALLING TO
AROUND 55 ON MONDAY. LOWS WILL BE IN THE MID 40S TO LOW 50S. BURKE

.LONG TERM...MODELS AGREE THE NEXT SYSTEM WILL BE NEARING THE COAST
MONDAY NIGHT. THERE IS A DEEP LOW ASSOCIATED WITH THIS SYSTEM THAT
IS FORECAST TO CROSS NORTHERN VANCOUVER ISLAND TUESDAY. SOUTHEAST
GRADIENTS WILL BE STRONG ACROSS WESTERN WASHINGTON BUT WITH THIS
PATTERN THERE IS USUALLY NO HIGH WIND. AFTER RAIN TUESDAY...SHOWERS
FOLLOW ON WEDNESDAY AND THURSDAY. ANOTHER SYSTEM MAY ARRIVE AROUND
NEXT FRIDAY. TEMPERATURES NEXT WEEK WILL BE NEAR SEASONAL NORMS WITH
HIGHS IN THE 50S AND LOWS IN THE 40S. BURKE

&&

.HYDROLOGY...THE SKOKOMISH RIVER WILL RISE AGAIN IN RESPONSE TO
HEAVY RAIN TONIGHT AND SATURDAY. SINCE IT IS STILL RUNNING HIGH FROM
THE PREVIOUS EVENT...IT IS POSSIBLE THE RIVER WILL GET CLOSE TO
FLOOD STAGE ON SATURDAY. FOR NOW THE FORECAST TAKES THE STAGE AT
POTLATCH TO BETWEEN 15.5 AND 16 FEET. FLOOD STAGE IS 16.5 FEET. ON
OTHER RIVERS FLOODING IS UNLIKELY OVER THE NEXT 7 DAYS.

&&

.AVIATION...SOUTHWEST FLOW ALOFT WILL CONTINUE OVER WESTERN
WASHINGTON THROUGH SATURDAY AS A PACIFIC FRONTAL SYSTEM MOVES INTO
THE REGION. THE AIR MASS WILL BECOME MOIST ALL LEVELS THIS EVENING
AS A WARM FRONT MOVES INTO THE AREA FROM THE SOUTH. THE SURFACE LOW
AND TRAILING COLD FRONT WILL MOVE INTO THE FORECAST AREA LATE
SATURDAY.

MAINLY VFR CONDITIONS PREVAIL ACROSS THE AREA THIS AFTERNOON AS HIGH
CLOUDS SPREAD ACROSS WESTERN WASHINGTON AHEAD OF THE APPROACHING
SYSTEM. RAIN BEGAN IN PORTLAND JUST BEFORE 2 PM. IT WILL REACH THE
SOUTH PART OF THE FORECAST AREA IN THE NEXT COUPLE HOURS...SEATTLE
AROUND 9 PM AND BELLINGHAM AROUND MIDNIGHT. CONDITIONS WILL
DETERIORATE OVERNIGHT...WITH WIDESPREAD LOW-END MVFR AND LOCAL IFR
FROM ROUGHLY 6 AM TO NOON SATURDAY. MARGINAL IMPROVEMENT IS LIKELY
SATURDAY.

KSEA...LIGHT WIND BECOMING NORTHEAST 5-12 KT..AND OCCASIONAL
EASTERLY GUSTS TO 20 KT ARE POSSIBLE TONIGHT. THE WIND WILL SHIFT TO
SOUTHERLY 8-16 KT SAT AFTERNOON. CONDITIONS WILL LIKELY DETERIORATE
TO LOW-END MVFR AND PERHAPS OCCASIONAL IFR IN RAIN AND FOG SATURDAY
MORNING.   MCDONNAL

&&

.MARINE...A WARM FRONT WILL MOVE NORTH ACROSS THE AREA TONIGHT. A
995 MB LOW ASSOCIATED WITH THE FRONT WILL MOVE NORTHEAST ACROSS THE
PACIFIC NORTHWEST COASTAL WATERS SATURDAY AND ACROSS WESTERN
WASHINGTON SATURDAY NIGHT. THIS FEATURE WILL LIKELY PRODUCE SMALL
CRAFT ADVISORY WINDS ALL WATERS AT SOME POINT LATE TONIGHT THROUGH
SATURDAY NIGHT...BEGINNING WITH THE COASTAL WATERS AND SPREADING
INLAND. IN ADDITION THERE IS A GOOD CHANCE OF SOUTHERLY GALES ALONG
THE INNER COASTAL WATERS SATURDAY MORNING AS THE LOW ARRIVES. THE
TRACK OF THE LOW IS STILL UNCERTAIN...AND CONFIDENCE IN THE DETAILS
OF THE FORECAST IS ACCORDINGLY LOW.

HIGH PRESSURE WILL BUILD OVER THE REGION SUNDAY AND BEGIN TO MOVE
EAST OF THE AREA MONDAY. ANOTHER VIGOROUS FRONTAL SYSTEM WILL AFFECT
THE AREA MONDAY NIGHT AND TUESDAY.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...WIND ADVISORY FOR THE EAST PUGET SOUND LOWLANDS TONIGHT THROUGH
     SATURDAY MORNING.
     WIND ADVISORY FOR BELLEVUE AND VICINITY TONIGHT.
PZ...GALE WARNING FOR INNER COASTAL WATERS ZONES PZZ153 AND PZZ156.
     SMALL CRAFT ADVISORY REMAINING COASTAL WATERS ZONES AND WEST
     ENTRANCE STRAIT OF JUAN DE FUCA.

&&

$$

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







000
FXUS66 KSEW 241602
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
900 AM PDT FRI OCT 24 2014

.SYNOPSIS...OFFSHORE SURFACE FLOW AND A WEAK RIDGE ALOFT WILL KEEP
WESTERN WASHINGTON DRY TODAY. RAIN WILL SPREAD FROM SOUTH TO NORTH
TONIGHT. A FILLING LOW PRESSURE CENTER WILL MOVE ACROSS THE AREA
SATURDAY NIGHT...BRINGING RAIN AND LOCALLY WINDY CONDITIONS. WET AND
BREEZY CONDITIONS ARE LIKELY AT TIMES NEXT WEEK.

&&

.SHORT TERM...TODAY WILL BE A QUIET AND MAINLY DRY DAY AS THE AREA
IS BETWEEN SYSTEMS. OFFSHORE SURFACE FLOW WILL CONTINUE TODAY THEN
INCREASE TONIGHT AS A DEEP LOW PRESSURE SYSTEM DEVELOPS OFF NORTHERN
CALIFORNIA AND MOVES NORTHEAST. A WIND ADVISORY IS IN EFFECT TONIGHT
FOR EAST WINDS OVER THE EAST PUGET SOUND LOWLANDS. RAIN WILL SPREAD
FROM SOUTH TO NORTH TONIGHT AS A WARM FRONT PASSES. AMOUNTS ARE
LIKELY TO BE PRETTY LIGHT EAST OF PUGET SOUND WHERE THE OFFSHORE
FLOW WILL MAKE THE AIR MASS DRIER.

ON SATURDAY AFTERNOON THE LOW...NOW FILLING...WILL REACH THE CENTRAL
COAST. IT WILL MOVE INLAND SATURDAY NIGHT. RAIN ALONG WITH BREEZY TO
WINDY CONDITIONS ARE LIKELY AFTER MIDNIGHT OVER MOST AREAS. ON
SUNDAY HIGH PRES WILL START TO BUILD AND SUNDAY NIGHT LOOKS CALM AND
DRIER. TEMPERATURES WILL BE SEASONAL ALL THREE DAYS. BURKE

.LONG TERM...PREVIOUS DISCUSSION...A LULL OR BREAK IN PRECIPITATION
IS POSSIBLE ON MONDAY BUT THE NEXT SYSTEM WILL BE QUICKLY
APPROACHING. THE 00Z MODELS HAVE TRENDED STRONGER WITH THE NEXT LOW
PRESSURE SYSTEM WHICH CONTAINS THE REMNANTS OF AN EX-TROPICAL
SYSTEM. FORTUNATELY IT WILL BE PROGRESSIVE WHICH WILL HELP LIMIT
RAIN AMOUNTS. THERE WILL BE A LOT OF GRADIENT WITH THIS LOW AND
LOCATIONS PRONE TO SE WIND...LIKE WHIDBEY ISLAND NWD...COULD SEE
SOME STRONG WINDS ON TUESDAY. MODELS WEAKEN THE LOW AS IT CROSSES
NEAR OR JUST N OF WA SO STRONG WINDS ARE NOT EXPECTED OVER OTHER
INLAND AREAS AT THIS POINT.

YET ANOTHER LOW PRESSURE SYSTEM LOOKS SET TO ARRIVE MID WEEK. MODELS
DIVERGE ON THE LONG WAVE TROUGH POSITION BY THURSDAY SO IT IS
DIFFICULT TO TELL WHETHER ADDITIONAL SYSTEMS WILL AFFECT OUR AREA.
THE ECMWF SHIFTS THE TROUGH FURTHER OFFSHORE AND THE GFS IS MORE
AGGRESSIVE KEEPING A TROUGH OVER THE PAC NW.  MERCER

&&

.HYDROLOGY...FLOODING IS UNLIKELY OVER THE NEXT 7 DAYS.

&&

.AVIATION...SOUTHWEST FLOW ALOFT WILL CONTINUE OVER WESTERN
WASHINGTON THROUGH TONIGHT AS A PACIFIC FRONTAL SYSTEM APPROACHES
THE REGION. THE AIR MASS WILL BECOME MOIST ALL LEVELS THIS EVENING
AS A WARM FRONT MOVES INTO THE FORECAST AREA FROM THE SOUTH.

MAINLY VFR CONDITIONS PREVAIL ACROSS THE AREA THIS MORNING WITH SKY
COVER SCT-BKN035 SCT-BKN120. HOWEVER ISOLATED FOG WITH LIFR
CONDITIONS WILL PERSIST IN THE SOUTH PUGET SOUND REGION AND
SOUTHWEST INTERIOR FOR THE NEXT COUPLE HOURS. RAIN WILL SPREAD FROM
SOUTH TO NORTH ACROSS THE FORECAST AREA THIS EVENING AND TONIGHT...
WITH CONDITIONS DETERIORATING TO WIDESPREAD LOW-END MVFR AND AREAS
OF IFR BY SATURDAY MORNING.

KSEA...LIGHT WIND BECOMING NORTHEAST 5-12 KT..AND OCCASIONAL
EASTERLY GUSTS TO 20 KT ARE POSSIBLE TONIGHT. CONDITIONS WILL LIKELY
DETERIORATE TO LOW-END MVFR AND OCCASIONAL IFR IN RAIN AND FOG
SATURDAY MORNING.   MCDONNAL

&&

.MARINE...HIGH PRESSURE OVER SOUTHEAST BRITISH COLUMBIA AND A
DEVELOPING LOW OFF THE NORTHERN CALIFORNIA WILL RESULT IN NORTHEAST
OFFSHORE FLOW TODAY. THE WARM FRONT ASSOCIATED WITH THE LOW WILL
MOVE NORTH THROUGH WESTERN WASHINGTON TONIGHT...AND THE LOW WILL
TRACK NORTHEAST INTO THE WESTERN WASHINGTON INTERIOR LATE SATURDAY
AFTERNOON. THIS FEATURE SHOULD PRODUCE SMALL CRAFT ADVISORY WINDS
LATE TONIGHT THROUGH SUNDAY MORNING. GALES ARE POSSIBLE BUT UNLIKELY
OVER THE COASTAL WATERS.

HIGH PRESSURE WILL BUILD OVER THE REGION FROM THE SOUTHWEST ON
SUNDAY AND REMAIN OVER THE AREA MONDAY. ANOTHER PACIFIC FRONTAL
SYSTEM AND ITS DEVELOPING LOW WILL PRODUCE SMALL CRAFT ADVISORY OR
POSSIBLY GALE FORCE WINDS OVER THE AREA MONDAY NIGHT AND TUESDAY.
MCDONNAL

&&

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...WIND ADVISORY FOR THE EAST PUGET SOUND LOWLANDS TONIGHT THROUGH
     SATURDAY MORNING.
     WIND ADVISORY FOR BELLEVUE AND VICINITY TONIGHT.
PZ...NONE.

&&

$$

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







000
FXUS66 KSEW 241025
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
330 AM PDT FRI OCT 24 2014

.SYNOPSIS...HIGHER PRESSURE ALOFT WILL BUILD OVER THE REGION TODAY
AS A STORM SYSTEM DEVELOPS OFFSHORE. A WARM FRONT WILL BRING SOME
RAIN BACK TO THE AREA FRIDAY NIGHT AND SATURDAY. LOW PRESSURE WILL
BRING RAIN AND LOCALLY WINDY CONDITIONS TO THE AREA SATURDAY NIGHT.
A SERIES OF SYSTEMS WILL KEEP THE WEATHER WET AND BREEZY AT TIMES
NEXT WEEK.

&&

.SHORT TERM....LATEST RADAR AND OBS INDICATE SHOWERS ARE PERSISTING
ACROSS WRN WA EARLY THIS MORNING. THE AIR MASS REMAINS UNSTABLE WITH
A WEAK SHORT WAVE OVER THE AREA. LIGHTNING DETECTION IS STILL
PICKING UP A FEW STRIKES NEAR THE W ENTRANCE TO THE STRAIT...BUT
NOTHING OVER THE INTERIOR. ACTIVITY APPEARS TO BE WANING COMPARED TO
LAST EVENING AND MODELS SHOW THIS DECREASING TREND TO CONTINUE.
MOSTLY DRY WEATHER AND PARTIAL SUNSHINE IS STILL ANTICIPATED THIS
AFTERNOON. THIS BREAK WILL BE SHORT LIVED HOWEVER AS ANOTHER
DEVELOPING SYSTEM APPROACHES THE PAC NW.

THE LATEST 00Z/06Z MODELS ARE IN FAIR AGREEMENT REGARDING THE
DEVELOPMENT OF THE LOW PRESSURE SYSTEM SEEN ON WV IMAGERY TRACKING
EWD NEAR 40 N INSIDE 140 W. UPPER LEVEL ENERGY DIVING SWD OVER THE
PACIFIC IS IN THE PROCESS OF PHASING WITH SRN STREAM MOISTURE.
CYCLOGENESIS WILL RESULT OVER THE NEXT 12-18 HOURS WITH THE
DEEPENING LOW APPROACHING 40 N/130 W TONIGHT. HOW DEEP THE LOW
BECOMES AND EXACTLY HOW IT CONSOLIDATES AND TRACKS TO THE N/NE WILL
DETERMINE HOW WINDY WE GET HERE IN PARTS OF WRN WA.

MODELS ALL AGREE THAT A WARM FRONT WILL REACH SRN PORTIONS OF WRN WA
THIS EVENING WITH A TRIPLE POINT FEATURE JUST OFFSHORE. LOW PRESSURE
NEAR THE COAST WILL CREATE STRONG CROSS CASCADE GRADIENTS AND THE
POTENTIAL FOR STRONG E WINDS NEAR THE FOOTHILLS EXTENDING AS FAR W
AS THE I405/BELLEVUE VICINITY. THE 00Z WRFGFS AND 00Z/06Z NAM12
SOLUTIONS HAVE BACKED OFF ON THE WIND TO SOME DEGREE BUT STILL SHOW
SOME 25-30 KT WIND MAXIMUMS ALONG THE FOOTHILL WHICH BRIEFLY EXTEND
TO I405 AROUND MIDNIGHT TONIGHT. CROSS SECTION DISPLAYS ON THE
WRFGFS/NAM12 BOTH SHOW SOME WEAK FLOW REVERSAL AT 700 MB AND 30-40
KT JUST OFF THE SURFACE E OF LAKE WASHINGTON. WILL ISSUE A WIND
ADVISORY FOR AREAS E OF LAKE WASHINGTON INCLUDING BELLEVUE AND
VICINITY FOR GUSTS 45-50 MPH...STRONGEST CLOSER TO THE FOOTHILLS.
THE ADVISORY WILL RUN THROUGH 18Z FOR THE FOOTHILLS BUT END SOONER
AT 12Z FOR THE BELLEVUE ZONE SINCE STRONGER WINDS THERE WILL BE
BRIEF.

LOW PRESSURE ASSOCIATED WITH THE WARM FRONT OFFSHORE WILL
SIGNIFICANTLY OUTRUN THE UPPER LEVEL ENERGY ASSOCIATED WITH THE MAIN
SURFACE LOW FEATURE OFF NRN CA/OREGON. VIRTUALLY ALL THE MODELS WANT
TO CONSOLIDATE THE LOW PRESSURE COMPLEX AS IT LIFTS N-NE SATURDAY
AFTERNOON. THE NAM12 CONTINUES TO BE FASTER GIVING THE SYSTEM LESS
TIME TO PHASE WITH THE NRN STREAM TROUGH. THIS RESULTS IN A
STRETCHED OUT SURFACE LOW FEATURE WITH THE BULK OF ENERGY GOING
INLAND S OF OUR AREA. OTHER MODELS ARE A BIT SLOWER AND FURTHER
OFFSHORE WITH THE LOW WHICH ALLOWS FOR BETTER CONSOLIDATION AS IT
APPROACHES THE N OREGON/S WA COASTS. 00Z GFS/ECMWF MODEL RUNS ARE IN
CLOSE AGREEMENT ON SLOWLY FILLING THE LOW AND TRACKING IT NE THROUGH
SRN WA NEAR PUGET SOUND. USUALLY THE ECMWF IS THE FAVORED MODEL AS
IT TENDS TO HANDLE SURFACE LOW DEVELOPMENT OFFSHORE THE BEST. THIS
IS HAPPENS TO BE THE STRONGEST OF THE MODELS WHICH STILL SHOWS
DECENT PRESSURE RISES BEHIND THE LOW AND A +12-13 MB KBLI-KPDX
GRADIENT WHICH WOULD SUPPORT WIND ADVISORY CRITERIA FOR PUGET SOUND.
AS USUAL...THE DEVIL IS IN THE DETAILS AND THE MESO MODELS FROM THE
NAM12 TO THE WRFGFS DO NOT CLEARLY SUPPORT THE STRONGER ECMWF
SOLUTION. TAKING EVERYTHING INTO ACCOUNT...THE POTENTIAL FOR STRONG
WINDS IN WRN WA HAS DECREASED. THE SPECIAL WEATHER STATEMENT WHICH
WAS TONED DOWN LAST EVENING WILL BE CONTINUED WITH A HIGH DEGREE OF
UNCERTAINTY.

LOW PRESSURE TRACKS OFF TO THE NE ON SUNDAY WITH STRONG ONSHORE FLOW
AND SHOWERY CONDITIONS. IT WILL BE NOTICEABLY COOLER IN THE MID 50S
DURING THE AFTERNOON WHICH WILL FEEL RATHER CHILLY GIVEN THE BREEZY
CONDITIONS.

.LONG TERM...A LULL OR BREAK IN PRECIPITATION IS POSSIBLE ON MONDAY
BUT THE NEXT SYSTEM WILL BE QUICKLY APPROACHING. THE 00Z MODELS HAVE
TRENDED STRONGER WITH THE NEXT LOW PRESSURE SYSTEM WHICH CONTAINS
THE REMNANTS OF AN EX-TROPICAL SYSTEM. FORTUNATELY IT WILL BE
PROGRESSIVE WHICH WILL HELP LIMIT RAIN AMOUNTS. THERE WILL BE A LOT
OF GRADIENT WITH THIS LOW AND LOCATIONS PRONE TO SE WIND...LIKE
WHIDBEY ISLAND NWD...COULD SEE SOME STRONG WINDS ON TUESDAY. MODELS
WEAKEN THE LOW AS IT CROSSES NEAR OR JUST N OF WA SO STRONG WINDS
ARE NOT EXPECTED OVER OTHER INLAND AREAS AT THIS POINT.

YET ANOTHER LOW PRESSURE SYSTEM LOOKS SET TO ARRIVE MID WEEK. MODELS
DIVERGE ON THE LONG WAVE TROUGH POSITION BY THURSDAY SO IT IS
DIFFICULT TO TELL WHETHER ADDITIONAL SYSTEMS WILL AFFECT OUR AREA.
THE ECMWF SHIFTS THE TROUGH FURTHER OFFSHORE AND THE GFS IS MORE
AGGRESSIVE KEEPING A TROUGH OVER THE PAC NW.  MERCER

&&

.HYDROLOGY...THERE WILL BE PERIODS OF RAIN OVER THE NEXT 7 DAYS BUT
AMOUNTS WILL NOT BE HYDROLOGICALLY SIGNIFICANT. THE SKOKOMISH RIVER
IN MASON COUNTY FELL BELOW FLOOD STAGE THIS EVENING AND FLOODING IS
NO LONGER EXPECTED.

&&

.AVIATION...SOUTHWESTERLY FLOW CONTINUING THROUGH TONIGHT. AIR MASS
STABLE. WARM FRONT MOVING UP FROM THE SOUTH TONIGHT.

CEILINGS STILL IN THE 4000 TO 6000 FOOT RANGE OVER THE INTERIOR IN
THE WAKE OF A BAND OF SHOWERS THAT MOVED THROUGH EARLY THIS MORNING.
CEILINGS ALONG THE COAST AOA 10000 FEET. CEILINGS WILL IMPROVE OVER
THE INTERIOR THIS MORNING TO AOA 10000 FEET. WARM FRONT MOVING UP
FROM THE SOUTH TONIGHT WITH CEILINGS LOWERING 00Z-06Z TO THE 3500 TO
5000 FOOT RANGE WITH RAIN BEGINNING AT THAT TIME AS WELL.

KSEA...CEILINGS 4000 TO 6000 FEET IMPROVE TO AOA 10000 FEET BY 16Z.
CEILINGS LOWERING AROUND 03Z TONIGHT BACK DOWN TO NEAR 4000 FEET
WITH RAIN. SOUTHEASTERLY WINDS 4 TO 8 KNOTS BECOMING NORTHEAST LATER
THIS MORNING. WINDS BECOMING EASTERLY 8 TO 12 KNOTS AFTER 03Z WITH
POSSIBLE GUSTS TO 20 KNOTS. FELTON

&&

.MARINE...LOW LEVEL OFFSHORE FLOW TODAY WITH HIGHER PRESSURE EAST OF
THE CASCADES AND A DEVELOPING SURFACE LOW OFF THE NORTHERN
CALIFORNIA COAST. WARM FRONT ASSOCIATED WITH THE LOW MOVING THROUGH
THE WATERS TONIGHT. SURFACE LOW WILL TRACK NORTHEAST INTO THE OREGON
WATERS ON SATURDAY REACHING THE WESTERN WASHINGTON INTERIOR LATE
SATURDAY AFTERNOON. SMALL CRAFT ADVISORY WINDS ARE EXPECTED AS THE
LOW APPROACHES. LAST COUPLE OF MODEL RUNS HAVE WEAKENED THE SURFACE
LOW AS IT REACHES WESTERN WASHINGTON SO HAVE KEPT WINDS BELOW GALE.
STRONGEST WINDS OVER THE INLAND WATERS BEHIND THE LOW SATURDAY NIGHT
INTO EARLY SUNDAY MORNING. HIGH PRESSURE BUILDING OVER THE WATERS
SUNDAY AND REMAINING INTO MONDAY. FRONT ASSOCIATED WITH A DEVELOPING
985 MB LOW APPROACHING VANCOUVER ISLAND WILL BRING AT LEAST SMALL
CRAFT ADVISORY WINDS BACK TO A PORTION OF THE WATERS MONDAY NIGHT
INTO TUESDAY. FELTON

&&

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...WIND ADVISORY FOR THE EAST PUGET SOUND LOWLANDS TONIGHT THROUGH
     SATURDAY MORNING.
     WIND ADVISORY FOR BELLEVUE AND VICINITY TONIGHT.

PZ...NONE.



&&

$$

WWW.WEATHER.GOV/SEATTLE

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000
FXUS66 KSEW 240503
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
1000 PM PDT THU OCT 23 2014

.SYNOPSIS...AN UPPER TROUGH WILL GIVE WAY TO WEAK HIGH PRESSURE
FRIDAY. A WARM FRONT WILL BRING SOME RAIN BACK TO THE AREA FRIDAY
NIGHT AND SATURDAY. A LOW PRESSURE SYSTEM WILL BRING RAIN AND WINDY
CONDITIONS TO THE AREA SATURDAY NIGHT. A SERIES OF SYSTEMS WILL KEEP
THE WEATHER WET AND BREEZY AT TIMES NEXT WEEK.

&&

.SHORT TERM....THAT LINE OF SHOWERS AND ISOLATED TSTMS MOVING ONTO
THE SOUTH WA COAST AT 10PM IS HOLDING TOGETHER...SO IT WILL LIKELY
REACH THE CENTRAL AND THEN THE NORTH WA COAST OVER THE NEXT SEVERAL
HOURS...FORECASTS UPDATED FOR THAT. BUT FOR THE INTERIOR THE
SCATTERED SHOWERS SHOULD END OVERNIGHT. FRIDAY WILL BE A DRY DAY AS
A LITTLE UPPER RIDGING AND OFFSHORE FLOW DEVELOP OVER THE AREA. THE
NEXT SYSTEM WILL HAVE A WARM FRONT DRAPED FROM A DEEP LOW CENTER OFF
NRN CALIF LATE FRIDAY...ACROSS NW OREGON AND ALONG THE WA/ORE
BORDER. THE FRONT MOVES NORTH OVERNIGHT FRIDAY NIGHT AND SHOULD BE
INTO VANCOUVER ISLAND AND SW B.C. BY MIDDAY SAT. THE NAM SHOWS THAT
THE LOW PRESSURE AREA GETS STRETCHED OUT ALONG THE WA AND ORE
COASTAL WATERS BY THAT TIME AS PRECIP FILLS IN OVER MOST OF WRN WA.
THE SURFACE LOW WILL MOVE TO THE INTERIOR OF WRN WA SATURDAY EVENING
AND GIVE BLUSTERY CONDITIONS IN STRONG ONSHORE FLOW. SUNDAY LOOKS
LIKE A COOL DAY WITH SCATTERED SHOWERS AND PERHAPS A PSCZ...SHOWERS
LIKELY IN THE MOUNTAINS...AND A SNOW LEVEL NEAR PASS LEVEL.

.LONG TERM...AFTER A BRIEF LULL IN PRECIPITATION ON MONDAY...ANOTHER
LOW WILL MOVE INLAND OVER VANCOUVER ISLAND ON TUESDAY BRINGING WET
AND POSSIBLY BREEZY WEATHER TO THE AREA. WET AND LOCALLY BREEZY
CONDITIONS IS EXPECTED TO CONTINUE WEDNESDAY AND THURSDAY AS YET
MORE FEATURES MOVE INTO THE AREA.

&&

.HYDROLOGY...PERIODS OF RAIN ARE EXPECTED OVER THE NEXT SEVERAL
DAYS...BUT RAINFALL AMOUNTS ARE NOT EXPECTED TO BE HYDROLOGICALLY
SIGNIFICANT. THE SKOKOMISH RIVER IN MASON COUNTY FELL BELOW FLOOD
STAGE THIS EVENING.

&&

.AVIATION...STRONG SOUTHWESTERLY FLOW TONIGHT WEAKENING ON FRIDAY.
AIR MASS REMAINING UNSTABLE OVERNIGHT THEN STABILIZING FRIDAY
MORNING. WARM FRONT MOVING UP FROM THE SOUTH FRIDAY NIGHT.

CEILINGS AOA 10000 FEET. THE EXCEPTION TO THIS WILL BE OVER THE NEXT
THREE HOURS AS ONE LAST BAND OF SHOWERS APPROACHING THE COAST AT 05Z
MOVES THROUGH THE AREA. CEILINGS LOWERING TO NEAR 4000 FEET IN THE
SHOWERS. BAND WILL BE THROUGH THE AREA BY 09Z. BETWEEN 10Z-16Z
ISOLATED VISIBILITIES 1-3SM WITH CEILINGS BELOW 500 FEET ALONG THE
I-5 CORRIDOR FROM ABOUT KOLM SOUTHWARD.

KSEA...BAND OF SHOWERS MOVING THROUGH AROUND 06Z TO 09Z WITH
CEILINGS LOWERING TO NEAR 5000 FEET. OUTSIDE OF THAT WINDOW CEILINGS
AOA 10000 FEET. SOUTHERLY WINDS 4 TO 8 KNOTS BECOMING SOUTHEAST
EARLY FRIDAY MORNING THEN NORTHEAST FRIDAY AFTERNOON. FELTON

&&

.MARINE...THE FLOW WILL WEAKEN AND BECOME MORE EASTERLY OVERNIGHT
DUE TO FALLING PRES OVER THE EASTERN PACIFIC. OFFSHORE FLOW WILL
PREVAIL ON FRIDAY AND WILL GRADUALLY STRENGTHEN IN RESPONSE TO A 992
MB LOW APPROACHING FROM THE SW. THIS LOW IS EXPECTED TO WEAKEN TO
996 MB AS IT MOVES ACROSS THE WASHINGTON COASTAL WATERS ON SATURDAY.
GALE FORCE WINDS ARE POSSIBLE OVER PARTS OF THE AREA SATURDAY AHEAD
OF AND BEHIND THE COLD OR OCCLUDED FRONT.

THERE CONTINUES TO BE SOME UNCERTAINTY IN REGARDS TO THE TRACK AND
STRENGTH OF THE LOW SATURDAY. THERE IS A POSSIBILITY OF GALE FORCE
WINDS OVER MUCH OF THE WATERS...IF THE NE MOVING LOW MOVES INTO FAR
SW BRITISH COLUMBIA. IF IT MOVES INTO NORTHERN OREGON OR TRACKS
ACROSS FAR SW WASHINGTON...THE THREAT OF GALE FORCE WINDS WILL BE
CONFINED TO A SMALL AREA. THE CURRENT FORECAST REFLECTS MODEL
CONSENSUS. FELTON

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WARNING REMAINS IN EFFECT FOR THE SKOKOMISH RIVER IN
     MASON COUNTY.

PZ...GALE WATCH IN EFFECT FOR THE COASTAL WATERS FROM SATURDAY
     MORNING THROUGH SATURDAY AFTERNOON.

&&

$$

WWW.WEATHER.GOV/SEATTLE

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000
FXUS66 KSEW 240435
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
930 PM PDT THU OCT 23 2014

.SYNOPSIS...AN UPPER TROUGH WILL GIVE WAY TO WEAK HIGH PRESSURE
FRIDAY. A WARM FRONT WILL BRING SOME RAIN BACK TO THE AREA FRIDAY
NIGHT AND SATURDAY. A LOW PRESSURE SYSTEM WILL BRING RAIN AND WINDY
CONDITIONS TO THE AREA SATURDAY NIGHT. A SERIES OF SYSTEMS WILL KEEP
THE WEATHER WET AND BREEZY AT TIMES NEXT WEEK.

&&

.SHORT TERM...SCATTERED SHOWERS SHOULD END OVERNIGHT AND FRIDAY WILL
BE A DRY DAY AS A LITTLE UPPER RIDGING AND OFFSHORE FLOW DEVELOP
OVER THE AREA. THE NEXT SYSTEM WILL HAVE A WARM FRONT DRAPED FROM A
DEEP LOW CENTER OFF NRN CALIF LATE FRIDAY...ACROSS NW OREGON AND
ALONG THE WA/ORE BORDER. THE FRONT MOVES NORTH OVERNIGHT FRIDAY
NIGHT AND SHOULD BE INTO VANCOUVER ISLAND AND SW B.C. BY MIDDAY SAT.
THE NAM SHOWS THAT THE LOW PRESSURE AREA GETS STRETCHED OUT ALONG
THE WA AND ORE COASTAL WATERS BY THAT TIME AS PRECIP FILLS IN OVER
MOST OF WRN WA. THE SURFACE LOW WILL MOVE TO THE INTERIOR OF WRN WA
SATURDAY EVENING AND GIVE BLUSTERY CONDITIONS IN STRONG ONSHORE
FLOW. SUNDAY LOOKS LIKE A COOL DAY WITH SCATTERED SHOWERS AND
PERHAPS A PSCZ...SHOWERS LIKELY IN THE MOUNTAINS...AND A SNOW LEVEL
NEAR PASS LEVEL.

.LONG TERM...AFTER A BRIEF LULL IN PRECIPITATION ON MONDAY...ANOTHER
LOW WILL MOVE INLAND OVER VANCOUVER ISLAND ON TUESDAY BRINGING WET
AND POSSIBLY BREEZY WEATHER TO THE AREA. WET AND LOCALLY BREEZY
CONDITIONS IS EXPECTED TO CONTINUE WEDNESDAY AND THURSDAY AS YET
MORE FEATURES MOVE INTO THE AREA.

&&

.HYDROLOGY...PERIODS OF RAIN ARE EXPECTED OVER THE NEXT SEVERAL
DAYS...BUT RAINFALL AMOUNTS ARE NOT EXPECTED TO BE HYDROLOGICALLY
SIGNIFICANT. THE SKOKOMISH RIVER IN MASON COUNTY FELL BELOW FLOOD
STAGE THIS EVENING.

&&

.AVIATION...STRONG SOUTHWESTERLY FLOW TONIGHT WEAKENING ON FRIDAY.
AIR MASS REMAINING UNSTABLE OVERNIGHT THEN STABILIZING FRIDAY
MORNING. WARM FRONT MOVING UP FROM THE SOUTH FRIDAY NIGHT.

CEILINGS AOA 10000 FEET. THE EXCEPTION TO THIS WILL BE OVER THE NEXT
THREE HOURS AS ONE LAST BAND OF SHOWERS APPROACHING THE COAST AT 05Z
MOVES THROUGH THE AREA. CEILINGS LOWERING TO NEAR 4000 FEET IN THE
SHOWERS. BAND WILL BE THROUGH THE AREA BY 09Z. BETWEEN 10Z-16Z
ISOLATED VISIBILITIES 1-3SM WITH CEILINGS BELOW 500 FEET ALONG THE
I-5 CORRIDOR FROM ABOUT KOLM SOUTHWARD.

KSEA...BAND OF SHOWERS MOVING THROUGH AROUND 06Z TO 09Z WITH
CEILINGS LOWERING TO NEAR 5000 FEET. OUTSIDE OF THAT WINDOW CEILINGS
AOA 10000 FEET. SOUTHERLY WINDS 4 TO 8 KNOTS BECOMING SOUTHEAST
EARLY FRIDAY MORNING THEN NORTHEAST FRIDAY AFTERNOON. FELTON

&&

.MARINE...THE FLOW WILL WEAKEN AND BECOME MORE EASTERLY OVERNIGHT
DUE TO FALLING PRES OVER THE EASTERN PACIFIC. OFFSHORE FLOW WILL
PREVAIL ON FRIDAY AND WILL GRADUALLY STRENGTHEN IN RESPONSE TO A 992
MB LOW APPROACHING FROM THE SW. THIS LOW IS EXPECTED TO WEAKEN TO
996 MB AS IT MOVES ACROSS THE WASHINGTON COASTAL WATERS ON SATURDAY.
GALE FORCE WINDS ARE POSSIBLE OVER PARTS OF THE AREA SATURDAY AHEAD
OF AND BEHIND THE COLD OR OCCLUDED FRONT.

THERE CONTINUES TO BE SOME UNCERTAINTY IN REGARDS TO THE TRACK AND
STRENGTH OF THE LOW SATURDAY. THERE IS A POSSIBILITY OF GALE FORCE
WINDS OVER MUCH OF THE WATERS...IF THE NE MOVING LOW MOVES INTO FAR
SW BRITISH COLUMBIA. IF IT MOVES INTO NORTHERN OREGON OR TRACKS
ACROSS FAR SW WASHINGTON...THE THREAT OF GALE FORCE WINDS WILL BE
CONFINED TO A SMALL AREA. THE CURRENT FORECAST REFLECTS MODEL
CONSENSUS. FELTON

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WARNING REMAINS IN EFFECT FOR THE SKOKOMISH RIVER IN
     MASON COUNTY.

PZ...GALE WATCH IN EFFECT FOR THE COASTAL WATERS FROM SATURDAY
     MORNING THROUGH SATURDAY AFTERNOON.

&&

$$

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 232259 CCA
AFDSEW

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SEATTLE WA
359 PM PDT THU OCT 23 2014

CORRECTED MINOR TYPO IN THE AVIATION SEGMENT.

.SYNOPSIS...AN UPPER TROUGH THAT IS GIVING SHOWERS AND THUNDERSTORMS
TO THE AREA THIS AFTERNOON WILL MOVE OUT OF THE AREA THIS EVENING.
SHOWERS WILL GRADUALLY COME TO AN END OVERNIGHT AND EARLY FRIDAY
MORNING. FRIDAY WILL BE MAINLY DRY BETWEEN WEATHER SYSTEMS. A WARM
FRONT WILL BRING SOME RAIN BACK TO THE AREA FRIDAY NIGHT AND
SATURDAY. LOW PRESSURE WILL BRING MORE RAIN AND WINDY CONDITIONS
LATE SATURDAY INTO SATURDAY NIGHT. A SERIES OF SYSTEMS WILL KEEP
CONDITIONS MAINLY WET AND BREEZY AT TIMES THROUGH MUCH OF NEXT WEEK.

&&

.SHORT TERM...A STRONG WSW 140-150 KT JET AT 300 MB AND AN
ASSOCIATED UPPER LEVEL TROUGH IS MOVING IN ACROSS NW OREGON AND SW
WASHINGTON TODAY. THESE FEATURES HAVE GIVEN SHOWERS AND
THUNDERSTORMS TO THE AREA THIS AFTERNOON...AND A FEW OF THE
THUNDERSTORMS HAVE BEEN SHOWING WEAK ROTATION ON OUR RADARS. ONE
LIKELY SEVERE STORM WAS LOCATED BY RADAR EARLIER THIS AFTERNOON IN
NORTHERN GRAYS HARBOR COUNTY. SHOWERS WILL GRADUALLY DIMINISH
TONIGHT AND COME TO AN END EARLY FRIDAY MORNING AS THE UPPER TROUGH
MOVES OFF TO THE NORTHEAST OF THE AREA AND SHORT WAVE RIDGING AND
OFFSHORE FLOW DEVELOPS DOWNSTREAM OF A DEVELOPING LOW NOW SEEN NEAR
38N 140W.

THE LOW NOW STARTING TO SHOW ITSELF WELL OFF THE NORTHERN CALIFORNIA
COAST IS DEVELOPING IN RESPONSE TO A COLD TROUGH THAT DROPPED DOWN
OUT OF THE BERING SEA AS IT PHASED WITH WARMTH AND MOISTURE
STREAMING EASTWARD AHEAD OF A SUBTROPICAL FEATURE OUT OVER THE WEST
CENTRAL PACIFIC. 18Z AND 12Z MODELS ARE A LITTLE WEAKER THAN
SOLUTIONS FROM LAST NIGHT...BUT THEY REMAIN CONSISTENT IN SHOWING
THE LOW BOTTOMING OUT AT AROUND 990 MB OFF THE OREGON COAST THEN
MOVING INLAND OVER SW WASHINGTON THEN INTO THE SEATTLE AREA SATURDAY
EVENING. THE LOW IS EXPECTED TO BE WEAKENING AS IT MOVES INLAND.

AHEAD OF THE LOW...OFFSHORE FLOW WILL BRING A DRY PERIOD ON FRIDAY.
THEN FRIDAY NIGHT AS LOW LEVEL FLOW REMAINS OFFSHORE...A FRONTAL
INVERSION ALOFT LOWERS...AND FLOW BECOMES SOUTHERLY AROUND 700
MB...WINDY CONDITIONS FROM AN EASTERLY DIRECTION ARE EXPECTED TO
DEVELOP FOR A FEW HOURS ALONG THE WEST SLOPES OF THE CASCADES. THIS
IS BEST SHOWN BY THE NAM12.

WIND SPEEDS WITH AND BEHIND THE LOW LATE SATURDAY AFTERNOON AND
SATURDAY NIGHT WILL REALLY DEPEND ON HOW DEEP THE LOW GETS...HOW
QUICKLY IT FILLS AS IT MOVES INLAND...AND ITS WIND FIELD STRUCTURE
AS IT MOVES INLAND. THE NAM12 AND ECMWF SHOW A SAGGY TROUGH TO THE
SOUTH OF THE LOW THAT WOULD INHIBIT A PUNCH OF STRONG PRESSURE RISES
BEHIND THE LOW. AT THIS POINT...FORECASTS INDICATE SOUTH TO
SOUTHWEST WINDS 20 TO 30 MPH WITH GUSTS TO 45 MPH BEHIND THE LOW. A
SPECIAL WEATHER STATEMENT WAS ISSUED JUST AS A HEADS UP. IF LATER
SOLUTIONS BECOME DEEPER WITH THE LOW AGAIN...A HIGH WIND WATCH MAY
BE NEEDED FOR PORTIONS OF THE FORECAST AREA FOR SATURDAY AFTERNOON
AND SATURDAY NIGHT.

POST FRONTAL SHOWERS IN ONSHORE FLOW WILL CONTINUE ON SUNDAY AND
WILL SLOWLY DECREASE SUNDAY NIGHT. ALBRECHT

.LONG TERM...AFTER A BRIEF LULL IN PRECIPITATION ON MONDAY...ANOTHER
LOW WILL MOVE INLAND OVER VANCOUVER ISLAND ON TUESDAY BRINGING WET
AND POSSIBLY BREEZY WEATHER TO THE AREA. WET AND LOCALLY BREEZY
CONDITIONS IS EXPECTED TO CONTINUE WEDNESDAY AND THURSDAY AS YET
MORE FEATURES MOVE INTO THE AREA. ALBRECHT

&&

.HYDROLOGY...PERIODS OF RAIN ARE EXPECTED OVER THE NEXT SEVERAL
DAYS...BUT RAINFALL AMOUNTS ARE NOT EXPECTED TO BE HYDROLOGICALLY
SIGNIFICANT.

THE SKOKOMISH RIVER IN MASON COUNTY REMAINS ABOVE FLOOD STAGE THIS
AFTERNOON...IT IS EXPECTED TO FALL BELOW FLOOD STAGE THIS
EVENING. REFER TO THE LATEST FLOOD STATEMENT BULLETIN FOR THE MOST
UP TO DATE INFORMATION.

&&

.AVIATION...STRONG WLY FLOW ALOFT WILL PERSIST OVERNIGHT. LOW LEVEL
SLY FLOW WILL DIMINISH OVERNIGHT. THE AIR MASS WAS UNSTABLE THIS
AFTERNOON...RESULTING IN SCATTERED TSTMS OVER THE AREA. EXPECT THE
AIR MASS TO STABILIZE AFTER SUNSET...WITH THE THREAT OF TSTMS
ENDING.

MEANWHILE...THERE WILL BE AREAS OF CIGS IN THE 2-3K FT RANGE WITH
THE HEAVIER SHOWERS THRU THIS EVENING. LOCALIZED VSBYS OF 2-5SM /DUE
TO FOG/ AND CIGS AOB 1K FT ARE EXPECTED LATE TONIGHT...MAINLY ALONG
THE I-5 CORRIDOR FROM ABOUT KOLM SWD.

KSEA...THERE WILL BE A RISK OF TSTMS OVER THE TERMINAL TIL ABOUT
0200 UTC. THE PRIMARY THREAT FROM THE TSTMS WILL BE BRIEF GUSTS TO
NEAR 25 KNOTS...HEAVY RAIN...AND SMALL HAIL. OTHERWISE VFR
CONDITIONS WILL PREVAIL OVER THE TERMINAL...ALTHOUGH A HEAVY SHOWER
THIS AFTERNOON COULD BRIEFLY REDUCE THE VSBY TO NEAR 2SM AND CIGS TO
NEAR 3K FT.

&&

.MARINE...
THE FLOW WILL WEAKEN AND BECOME MORE EASTERLY OVERNIGHT DUE TO
FALLING PRES OVER THE EASTERN PACIFIC. OFFSHORE FLOW WILL PREVAIL ON
FRI AND WILL GRADUALLY STRENGTHEN IN RESPONSE TO A 990 MB LOW
APPROACHING FROM THE SW. THIS LOW IS EXPECTED TO WEAKEN TO 993 MB AS
IT MOVES ACROSS THE WASHINGTON COASTAL WATERS ON SATURDAY. GALE
FORCE WINDS ARE POSSIBLE OVER PARTS OF THE AREA SATURDAY AHEAD OF
AND BEHIND THE COLD OR OCCLUDED FRONT.

THERE CONTINUED TO BE SOME UNCERTAINTY IN REGARDS TO THE TIMING...
TRACK...AND STRENGTH OF THE LOW THAT IS EXPECTED ON SATURDAY. THERE
IS A POSSIBILITY OF GALE FORCE WINDS OVER MUCH OF THE WATERS...IF
THE NE MOVING LOW MOVES INTO FAR SW BRITISH COLUMBIA. IF IT MOVES
INTO NORTHERN OREGON OR TRACKS ACROSS FAR SW WASHINGTON...THE THREAT
OF GALE FORCE WINDS WILL BE CONFINED TO A SMALL AREA. THE FORECAST
REFLECTS THE MODEL CONSENSUS.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WARNING REMAINS IN EFFECT FOR THE SKOKOMISH RIVER IN
     MASON COUNTY.

PZ...SMALL CRAFT ADVISORIES REMAIN IN EFFECT FOR MUCH OF THE
     COASTAL WATERS...CENTRAL STRAIT OF JUAN DE FUCA...NORTHERN
     INLAND WATERS...AND PUGET SOUND TIL 6 PM PDT TODAY.

     GALE WATCH IN EFFECT FOR THE COASTAL WATERS FROM SATURDAY
     MORNING THROUGH SATURDAY AFTERNOON.

$$

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 232256
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
355 PM PDT THU OCT 23 2014

.SYNOPSIS...AN UPPER TROUGH THAT IS GIVING SHOWERS AND THUNDERSTORMS
TO THE AREA THIS AFTERNOON WILL MOVE OUT OF THE AREA THIS EVENING.
SHOWERS WILL GRADUALLY COME TO AN END OVERNIGHT AND EARLY FRIDAY
MORNING. FRIDAY WILL BE MAINLY DRY BETWEEN WEATHER SYSTEMS. A WARM
FRONT WILL BRING SOME RAIN BACK TO THE AREA FRIDAY NIGHT AND
SATURDAY. LOW PRESSURE WILL BRING MORE RAIN AND WINDY CONDITIONS
LATE SATURDAY INTO SATURDAY NIGHT. A SERIES OF SYSTEMS WILL KEEP
CONDITIONS MAINLY WET AND BREEZY AT TIMES THROUGH MUCH OF NEXT WEEK.

&&

.SHORT TERM...A STRONG WSW 140-150 KT JET AT 300 MB AND AN
ASSOCIATED UPPER LEVEL TROUGH IS MOVING IN ACROSS NW OREGON AND SW
WASHINGTON TODAY. THESE FEATURES HAVE GIVEN SHOWERS AND
THUNDERSTORMS TO THE AREA THIS AFTERNOON...AND A FEW OF THE
THUNDERSTORMS HAVE BEEN SHOWING WEAK ROTATION ON OUR RADARS. ONE
LIKELY SEVERE STORM WAS LOCATED BY RADAR EARLIER THIS AFTERNOON IN
NORTHERN GRAYS HARBOR COUNTY. SHOWERS WILL GRADUALLY DIMINISH
TONIGHT AND COME TO AN END EARLY FRIDAY MORNING AS THE UPPER TROUGH
MOVES OFF TO THE NORTHEAST OF THE AREA AND SHORT WAVE RIDGING AND
OFFSHORE FLOW DEVELOPS DOWNSTREAM OF A DEVELOPING LOW NOW SEEN NEAR
38N 140W.

THE LOW NOW STARTING TO SHOW ITSELF WELL OFF THE NORTHERN CALIFORNIA
COAST IS DEVELOPING IN RESPONSE TO A COLD TROUGH THAT DROPPED DOWN
OUT OF THE BERING SEA AS IT PHASED WITH WARMTH AND MOISTURE
STREAMING EASTWARD AHEAD OF A SUBTROPICAL FEATURE OUT OVER THE WEST
CENTRAL PACIFIC. 18Z AND 12Z MODELS ARE A LITTLE WEAKER THAN
SOLUTIONS FROM LAST NIGHT...BUT THEY REMAIN CONSISTENT IN SHOWING
THE LOW BOTTOMING OUT AT AROUND 990 MB OFF THE OREGON COAST THEN
MOVING INLAND OVER SW WASHINGTON THEN INTO THE SEATTLE AREA SATURDAY
EVENING. THE LOW IS EXPECTED TO BE WEAKENING AS IT MOVES INLAND.

AHEAD OF THE LOW...OFFSHORE FLOW WILL BRING A DRY PERIOD ON FRIDAY.
THEN FRIDAY NIGHT AS LOW LEVEL FLOW REMAINS OFFSHORE...A FRONTAL
INVERSION ALOFT LOWERS...AND FLOW BECOMES SOUTHERLY AROUND 700
MB...WINDY CONDITIONS FROM AN EASTERLY DIRECTION ARE EXPECTED TO
DEVELOP FOR A FEW HOURS ALONG THE WEST SLOPES OF THE CASCADES. THIS
IS BEST SHOWN BY THE NAM12.

WIND SPEEDS WITH AND BEHIND THE LOW LATE SATURDAY AFTERNOON AND
SATURDAY NIGHT WILL REALLY DEPEND ON HOW DEEP THE LOW GETS...HOW
QUICKLY IT FILLS AS IT MOVES INLAND...AND ITS WIND FIELD STRUCTURE
AS IT MOVES INLAND. THE NAM12 AND ECMWF SHOW A SAGGY TROUGH TO THE
SOUTH OF THE LOW THAT WOULD INHIBIT A PUNCH OF STRONG PRESSURE RISES
BEHIND THE LOW. AT THIS POINT...FORECASTS INDICATE SOUTH TO
SOUTHWEST WINDS 20 TO 30 MPH WITH GUSTS TO 45 MPH BEHIND THE LOW. A
SPECIAL WEATHER STATEMENT WAS ISSUED JUST AS A HEADS UP. IF LATER
SOLUTIONS BECOME DEEPER WITH THE LOW AGAIN...A HIGH WIND WATCH MAY
BE NEEDED FOR PORTIONS OF THE FORECAST AREA FOR SATURDAY AFTERNOON
AND SATURDAY NIGHT.

POST FRONTAL SHOWERS IN ONSHORE FLOW WILL CONTINUE ON SUNDAY AND
WILL SLOWLY DECREASE SUNDAY NIGHT. ALBRECHT

.LONG TERM...AFTER A BRIEF LULL IN PRECIPITATION ON MONDAY...ANOTHER
LOW WILL MOVE INLAND OVER VANCOUVER ISLAND ON TUESDAY BRINGING WET
AND POSSIBLY BREEZY WEATHER TO THE AREA. WET AND LOCALLY BREEZY
CONDITIONS IS EXPECTED TO CONTINUE WEDNESDAY AND THURSDAY AS YET
MORE FEATURES MOVE INTO THE AREA. ALBRECHT

&&

.HYDROLOGY...PERIODS OF RAIN ARE EXPECTED OVER THE NEXT SEVERAL
DAYS...BUT RAINFALL AMOUNTS ARE NOT EXPECTED TO BE HYDROLOGICALLY
SIGNIFICANT.

THE SKOKOMISH RIVER IN MASON COUNTY REMAINS ABOVE FLOOD STAGE THIS
AFTERNOON...IT IS EXPECTED TO FALL BELOW FLOOD STAGE THIS
EVENING. REFER TO THE LATEST FLOOD STATEMENT BULLETIN FOR THE MOST
UP TO DATE INFORMATION.

&&

.AVIATION...STRONG WLY FLOW ALOFT WILL PERSIST OVERNIGHT. LOW LEVEL
SLY FLOW WILL DIMINISH OVERNIGHT. THE AIR MASS WAS UNSTABLE THIS
AFTERNOON...RESULTING SCATTERED TSTMS OVER THE AREA. EXPECT THE AIR
MASS TO STABILIZE AFTER SUNSET...WITH THE THREAT OF TSTMS ENDING.

MEANWHILE...THERE WILL BE AREAS OF CIGS IN THE 2-3K FT RANGE WITH
THE HEAVIER SHOWERS THRU THIS EVENING. LOCALIZED VSBYS OF 2-5SM /DUE
TO FOG/ AND CIGS AOB 1K FT ARE EXPECTED LATE TONIGHT...MAINLY ALONG
THE I-5 CORRIDOR FROM ABOUT KOLM SWD.

KSEA...THERE WILL BE A RISK OF TSTMS OVER THE TERMINAL TIL ABOUT
0200 UTC. THE PRIMARY THREAT FROM THE TSTMS WILL BE BRIEF GUSTS TO
NEAR 25 KNOTS...HEAVY RAIN...AND SMALL HAIL. OTHERWISE VFR
CONDITIONS WILL PREVAIL OVER THE TERMINAL...ALTHOUGH A HEAVY SHOWER
THIS AFTERNOON COULD BRIEFLY REDUCE THE VSBY TO NEAR 2SM AND CIGS TO
NEAR 3K FT.

&&

.MARINE...
THE FLOW WILL WEAKEN AND BECOME MORE EASTERLY OVERNIGHT DUE TO
FALLING PRES OVER THE EASTERN PACIFIC. OFFSHORE FLOW WILL PREVAIL ON
FRI AND WILL GRADUALLY STRENGTHEN IN RESPONSE TO A 990 MB LOW
APPROACHING FROM THE SW. THIS LOW IS EXPECTED TO WEAKEN TO 993 MB AS
IT MOVES ACROSS THE WASHINGTON COASTAL WATERS ON SATURDAY. GALE
FORCE WINDS ARE POSSIBLE OVER PARTS OF THE AREA SATURDAY AHEAD OF
AND BEHIND THE COLD OR OCCLUDED FRONT.

THERE CONTINUED TO BE SOME UNCERTAINTY IN REGARDS TO THE TIMING...
TRACK...AND STRENGTH OF THE LOW THAT IS EXPECTED ON SATURDAY. THERE
IS A POSSIBILITY OF GALE FORCE WINDS OVER MUCH OF THE WATERS...IF
THE NE MOVING LOW MOVES INTO FAR SW BRITISH COLUMBIA. IF IT MOVES
INTO NORTHERN OREGON OR TRACKS ACROSS FAR SW WASHINGTON...THE THREAT
OF GALE FORCE WINDS WILL BE CONFINED TO A SMALL AREA. THE FORECAST
REFLECTS THE MODEL CONSENSUS.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...FLOOD WARNING IN EFFECT FOR THE SKOKOMISH RIVER IN MASON
      COUNTY.

PZ...SMALL CRAFT ADVISORIES REMAIN IN EFFECT FOR MUCH OF THE
      COASTAL WATERS...CENTRAL STRAIT OF JUAN DE FUCA...
      NORTHERN      INLAND WATERS...AND PUGET SOUND TIL 6 PM PDT
      TODAY.

     GALE WATCH IN EFFECT FOR THE COASTAL WATERS FROM SATURDAY
     MORNING THROUGH SATURDAY AFTERNOON.

$$

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 231631
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
930 AM PDT THU OCT 23 2014

.SYNOPSIS...AN UPPER TROUGH WILL MAINTAIN SHOWERY WEATHER OVER
WESTERN WASHINGTON TODAY. THE AIR MASS WILL BE UNSTABLE ENOUGH FOR A
CHANCE OF THUNDERSTORMS. SHOWERS WILL GRADUALLY DECREASE LATER
TONIGHT. FRIDAY WILL BE MOSTLY DRY BETWEEN WEATHER SYSTEMS. A WARM
FRONT WILL BRING SOME RAIN BACK TO THE AREA FRIDAY NIGHT AND
SATURDAY. LOW PRESSURE WILL BRING MORE RAIN SATURDAY NIGHT AND
SUNDAY WITH WINDY CONDITIONS POSSIBLE.

&&

.SHORT TERM...A STRONG WSW 140-150 KT JET AT 300 MB IS AIMED AT NW
OREGON AND SW WASHINGTON TODAY. THIS WILL KEEP THE AREA IN A
FAVORED REGION OF UPPER LEVEL LIFT. WIDESPREAD SHOWERS ARE SEEN OVER
THE AREA THIS MORNING WITH SOME TSTMS SEEN FROM AROUND VANCOUVER BC
SW TO FORKS AND SOME MORE TSTM ACTIVITY FROM THE SW OLYMPICS TO OFF
THE MOUTH OF THE COLUMBIA RIVER IN THE N OREGON COASTAL WATERS. THE
AIR MASS WILL REMAIN UNSTABLE ENOUGH TODAY TO PRODUCE A CHANCE OF
THUNDERSTORM ACTIVITY THROUGH THE AREA TODAY.

A SHORT WAVE TROUGH EXTENDING FROM THE MAIN GULF OF ALASKA LOW
CENTERED NEAR 53N 142W SOUTHWESTWARD TO 44N 165W IS DROPPING
SOUTHEASTWARD. THIS TROUGH IS EXPECTED TO PHASE WITH SOME
SUBTROPICAL MOISTURE AND ENERGY FROM THE CENTRAL PACIFIC TO CAUSE
RAPID DEVELOPMENT OF A SYSTEM AROUND 40N 132W LATER FRI. DOWNSTREAM
FROM THIS SYSTEM MODELS ARE CONSISTENT IN FORMING WEAK SHORT WAVE
RIDGING OVER THE PACIFIC NORTHWEST AND STRENGTHENING SURFACE HIGH
PRES OVER NE WA. THE END RESULT FOR OUR AREA WILL BE A DECREASE IN
SHOWER ACTIVITY THU NIGHT AND A RATHER DRY DAY ON FRIDAY IN LOW
LEVEL OFFSHORE FLOW...ALTHOUGH THERE WILL BE QUITE A BIT OF MID AND
HIGH CLOUDS AROUND.

THE 12Z NAM12 AND GFS BOTH SHOW THE LOW BECOMING VERTICALLY STACKED
AS IT REACHES ITS MAXIMUM DEPTH AROUND THE NW OREGON OFFSHORE WATERS
SAT MORNING. THIS WILL INCREASE THE LOW LEVEL OFFSHORE FLOW OVER THE
AREA...BUT WITH 700 MB FLOW TURNING TO THE S AND 850 MB FLOW FROM
THE EAST WITH A GRADUALLY LOWERING FRONTAL INVERSION...MAY
RESULT IN SOME MOUNTAIN WAVE ACTIVITY NEAR THE FOOTHILLS OF THE
CASCADES. SOME AREAS EAST OF INTERSTATE 405 IN THE CENTRAL PUGET
SOUND AREA MAY GET RATHER WINDY FRI NIGHT INTO EARLY SATURDAY
MORNING. WHILE THE GFS SHOWS 0.25 TO 0.5 INCHES OF RAIN FRI NIGHT OR
EARLY SAT AS A STRONG WARM FRONT LIFTS NORTH ACROSS THE
AREA...PRECIPITATION AMOUNTS WILL LIKELY GET CUT BACK NEAR THE
CASCADES AS A RESULT OF THE GUSTY EASTERLY WINDS.

THE FORECAST FOR SATURDAY INTO SATURDAY EVENING WILL BE TRICKY AND
WILL DEPEND ON THE TRACK AND DEPTH OF THE OFFSHORE LOW AS IT MOVES
NE ACROSS THE PACIFIC NW. MODELS HAVE GENERALLY COME INTO A
CONSENSUS THAT THE LOW WILL DEEPEN TO 977-990 MB OFF THE NW OREGON
OFFSHORE WATERS THEN SLOWLY FILL TO 985-995 MB AS IT LIFTS NE TO
A TRACK FROM ABOUT HOQUIAM TO SEATTLE THEN INTO THE N CASCADES.
KPDX-KBLI PRES GRADIENTS RANGE FROM 10 MB IN THE WEAKER AND SOMEWHAT
LESS DEVELOPED 12Z GFS...TO UP TO 15 MB IN THE 12Z NAM12 AND 00Z
CANADIAN SOLUTIONS AND 12-14 MB IN THE 00Z ECMWF. THE GFS TENDS TO
BE A BIT UNDERDEVELOPED WITH THESE SYSTEMS. THIS WOULD HINT THAT THE
COAST AND THE INTERIOR FROM SEATTLE SOUTHWARD COULD SEE SOME WINDS
TOUCH THE HIGH WIND CRITERIA --35-40 MB WITH GUSTS TO 50-60 MPH--
FOR A FEW HOURS LATE SAT AFTERNOON OR EVENING. WILL LIKELY ISSUE A
SPECIAL WEATHER STATEMENT EARLY THIS AFTERNOON AFTER LOOKING AT THE
WRFGFS...12Z CANADIAN AND ECMWF SOLUTIONS. ALBRECHT

.LONG TERM...SHOWERS ARE EXPECTED ON SUN WITH ONSHORE FLOW BEHIND
THE LOW THAT TRACKS ACROSS THE AREA LATE SAT OR SAT NIGHT AND THEY
ARE EXPECTED TO PERSIST INTO SUN NIGHT. MONDAY WILL LIKELY BE A LULL
BETWEEN SYSTEMS.

THE GFS BRINGS THE NEXT SYSTEM CONTAINING THE REMNANTS OF ANA INTO
THE AREA MONDAY NIGHT AND TUESDAY. MOST MODELS RAPIDLY FILL THE LOW
RAPIDLY AS IT APPROACHES SO WIND MAY NOT BE AN ISSUE BUT IT ALSO
BARES WATCHING. IT SHOULD BRING RAIN BACK INTO THE AREA BUT AT THIS
POINT IT LOOKS TO BE A PROGRESSIVE SYSTEM WHICH WILL LIMIT THE FLOOD
POTENTIAL. ADDITIONAL LOW PRESSURE SYSTEM MAY BRING RAIN INTO THE
AREA THROUGH MID WEEK.  MERCER/ALBRECHT

&&

.HYDROLOGY...SHOWERS WILL PERSIST TODAY BUT ADDITIONAL RAIN AMOUNTS
WILL NOT BE HYDROLOGICALLY SIGNIFICANT. THE SKOKOMISH RIVER WILL
REMAIN ABOVE FLOOD STAGE BUT GRADUALLY RECEDE TODAY...FALLING BELOW
FLOOD STAGE THIS EVENING. REFER TO THE LATEST FLOOD STATEMENT
BULLETIN FOR THE MOST UP TO DATE INFORMATION.

WET WEATHER IS EXPECTED TO CONTINUE THROUGH THE UPCOMING WEEK. BUT
RAINFALL AMOUNTS ARE NOT EXPECTED TO DRIVE ANY RIVERS ABOVE FLOOD
STAGE. MERCER/ALBRECHT

&&

.AVIATION...AIR MASS UNSTABLE OVER WESTERN WASHINGTON TODAY AND
TONIGHT WITH SOUTHWESTERLY FLOW ALOFT.

NOTHING REALLY ORGANIZED MOVING THROUGH THE AREA TODAY BUT SATELLITE
IMAGERY SHOWS PLENTY OF SHOWERS EMBEDDED IN THE SOUTHWESTERLY FLOW
ALOFT OFFSHORE EXTENDING BACK TO NEAR 160W. IN GENERAL CEILINGS IN
THE 4000 TO 6000 FOOT RANGE LOWERING DOWN TO NEAR 2000 FEET WITH
VISIBILITIES 3-5SM BRIEFLY IN THE HEAVIER SHOWERS. THE AIR MASS IS
UNSTABLE ENOUGH FOR THE POSSIBILITY OF ISOLATED THUNDERSTORMS. THE
CHANCE FOR THUNDERSTORMS IS NOT HIGH ENOUGH TO INCLUDE IN THE TAFS.

KSEA...CEILINGS IN THE 4000-6000 FOOT RANGE DROPPING DOWN TO NEAR
2000 FEET IN THE HEAVIER SHOWERS LATE THIS MORNING INTO THE
AFTERNOON HOURS. FELTON

&&

.MARINE...
LOWER PRES OVER BRITISH COLUMBIA AND HIGHER PRES OVER CALIFORNIA
WILL RESULT IN SOUTHERLY FLOW TODAY. THE FLOW WILL BECOME EASTERLY
ON FRI DUE TO A SURFACE LOW APPROACHING FROM THE SW. THIS LOW WILL
DEEPEN TO 987 MB OFF THE OREGON COAST. EXPECT IT TO WEAKEN TO 990 MB
AS IT MOVES ACROSS THE WASHINGTON COASTAL WATERS SATURDAY NIGHT.

THE NUMERICAL WEATHER MODELS WERE STILL NOT IN GOOD AGREEMENT WITH
THE TRACK...TIMING...AND STRENGTH OF THE LOW THAT IS EXPECTED THE
END OF THIS WEEK. DEPENDING ON WHICH MODEL IS CORRECT...THIS SYSTEM
COULD PRODUCE ANYWHERE FROM HIGH END GALE OR LOW END STORM FORCE
WINDS OVER PARTS OF THE AREA OR INCONSEQUENTIAL WIND SPEEDS. THE
FORECAST REFLECTS THE CONSENSUS.


&&

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...FLOOD WARNING IN EFFECT FOR THE SKOKOMISH RIVER IN MASON
      COUNTY.

PZ...SMALL CRAFT ADVISORIES ARE IN EFFECT FOR MUCH OF THE
      COASTAL WATERS...CENTRAL/EASTERN STRAIT OF JUAN DE
      FUCA...NORTHERN INLAND WATERS...ADMIRALTY INLET...AND PUGET
      SOUND.

     SMALL CRAFT ADVISORY FOR ROUGH BAR UNTIL 8 PM PDT THIS
      EVENING FOR THE GRAYS HARBOR BAR.

$$

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000
FXUS66 KSEW 231033
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
330 AM PDT THU OCT 23 2014

.SYNOPSIS...AN UPPER TROUGH WILL MAINTAIN SHOWERY WEATHER OVER
WESTERN WASHINGTON TODAY. THE AIR MASS WILL BE UNSTABLE ENOUGH FOR A
CHANCE OF THUNDERSTORMS. SHOWERS WILL GRADUALLY DECREASE LATER
THURSDAY NIGHT. FRIDAY WILL BE MOSTLY DRY BETWEEN WEATHER SYSTEMS. A
WARM FRONT WILL BRING SOME RAIN BACK TO THE AREA FRIDAY NIGHT AND
SATURDAY. LOW PRESSURE WILL BRING MORE RAIN SATURDAY NIGHT AND
SUNDAY WITH SOME LOCALLY WINDY CONDITIONS POSSIBLE.

&&

.SHORT TERM...A STRONG WESTERLY 140-150KT JET WILL STAY AIMED INTO
OREGON TODAY KEEPING WRN UNDER A FAVORED REGION OF LIFT. A SHORT
WAVE SEEN ON SATELLITE IMAGERY APPROACHING THE COAST WILL HELP TO
ENHANCE SHOWER ACTIVITY ACROSS THE AREA. THE IR SATELLITE IMAGE
INDICATES COOLING CLOUD TOPS SO THE IDEA OF INCREASED INSTABILITY
TODAY LOOKS ON TRACK. MODEL LI`S ARE FORECAST -1 TO -2C WITH CAPE UP
TO 500J/KG WHICH WILL SUPPORT A CHANCE FOR EMBEDDED THUNDERSTORMS.
LIGHTING DETECTION IS ALREADY SHOWING STRIKES JUST OFFSHORE AND ALSO
OVER WHATCOM COUNTY UNDER AN ENHANCED BAND OF SHOWERS. MODELS ARE
HINTING THAT SURFACE RIDGING MAY DEVELOP LATER TODAY W OF PUGET
SOUND. THIS COULD GENERATE A CONVERGENCE ZONE AROUND WRN SNOHOMISH
COUNTY LATER IN THE DAY. IT IS UNLIKELY TO PERSIST VERY LONG AS THE
JET LIFTS NWD DIRECTLY OVER WRN WA AND THE SURFACE PATTERN WEAKENS
TONIGHT.

THE FLOW BECOME MORE ZONAL TONIGHT BUT THE GFS STILL BRINGS ANOTHER
WEAK DISTURBANCE INTO THE AREA. SHOWERS WILL BE POSSIBLE UNTIL THE
FLOW LIFTS FAR ENOUGH TO THE N SO THAT THE JET BECOMES DIRECTED INTO
B.C. RATHER THAN WA. THIS SHOULD HAPPEN FRIDAY MORNING...SO SHOWERS
SHOULD BE ON THE DECREASE AND MOSTLY END BY AFTERNOON. ANY BREAK IN
RAINFALL FRIDAY WILL BE BRIEF AS ANOTHER SYSTEM WILL BE ORGANIZING
OFFSHORE.

00Z MODELS ARE COMING INTO BETTER AGREEMENT WITH REGARDS TO THE
SYSTEM EXPECTED TO AFFECT THE REGION OVER THE WEEKEND. A COLD NRN
STREAM TROUGH ORIGINATING FROM THE BERING SEA CAN BEEN SEEN ON WATER
VAPOR QUICKLY DRIVING SWD OVER THE PACIFIC. THE COLD AIR MASS WILL
ENCOUNTER THE ATMOSPHERIC RIVER OF MOISTURE THAT HAS TAPPED THE
TROPICS. WHEN THESE TWO MERGE LATER TODAY AND TONIGHT...CYCLOGENESIS
WILL OCCUR ALONG THE BAROCLINIC BOUNDARY JUST S OF 40 N AND
130-140W. AS SURFACE LOW PRESSURE DEEPENS THE FLOW OVER THE PAC NW
WILL LIFT NWD. A WARM FRONT OUT AHEAD OF THIS SYSTEM WILL REACH WRN
WA FRIDAY NIGHT WITH SOME WARM ADVECTION RAIN DEVELOPING ACROSS THE
AREA. AREAS SUSCEPTIBLE TO ELY FLOW SUCH AS THE FOOTHILLS AND GAPS
NEAR THE COASTAL WATERS MAY BECOME BREEZY UNTIL THE WARM FRONT LIFTS
N.

MODELS MOSTLY AGREE THAT THE SURFACE LOW WILL DEEPEN TO ROUGHLY
980-985 MB AS IT WOBBLES NWD ALONG 130 W OFF THE NRN CA/S OREGON
COASTS FRIDAY NIGHT. THE LOW SHOULD REACH THE NRN OREGON OR S WA
COASTAL WATERS ON SATURDAY BUT SHOULD ALSO BE IN THE PROCESS OF
FILLING. IT REMAINS UNCLEAR HOW DEEP AND CONSOLIDATED THE LOW WILL
REMAIN AS IT APPROACHES ON SATURDAY. THE 00Z MODEL TRACKS ARE
CLUSTERED AROUND THE LOW REACHING THE S WA COAST BY SATURDAY EVENING
BUT FILLING AS IT MOVES ONSHORE. THIS SYSTEM BARES WATCHING AS THE
REGION OF DEVELOPMENT AND TRACK ARE FAVORABLE FOR STRONG WINDS IN
OUR AREA. IT IS IMPORTANT TO NOTE HOWEVER THAT MOST MODELS ARE
SHOWING MATURE DEVELOPMENT BY LATE FRIDAY...THEN SLOWLY FILL THE LOW
AS IT REACHES THE PAC NW WHICH WOULD LIMIT WIND POTENTIAL. SOME
MODELS ALSO DO NOT FULLY CONSOLIDATE THE LOW OR THEY BRING IT INLAND
S OF PUGET SOUND WHICH COULD KEEP STRONGER WINDS S OF THE AREA. A
LOT COULD CHANGE OVER THE NEXT COUPLE DAYS SO IT WILL BE A GOOD IDEA
TO MONITOR FORECASTS.

.LONG TERM...MOST MODELS TRACK LOW PRESSURE NE ACROSS WA ON SUNDAY.
IT COULD BE BREEZY TO LOCALLY WINDY DEPENDING ON THE TRACK. RAIN IS
LIKELY EARLY ON BUT WILL BECOME SHOWERY AS ONSHORE FLOW INCREASES
BEHIND THE LOW. SHOWERS WILL PERSIST INTO SUNDAY NIGHT WILL A LULL
ON MONDAY BETWEEN SYSTEMS.

THE GFS BRINGS THE NEXT SYSTEM CONTAINING THE REMNANTS OF ANNA INTO
THE AREA MONDAY NIGHT AND TUESDAY. MOST MODELS RAPIDLY FILL THE LOW
RAPIDLY AS IT APPROACHES SO WIND MAY NOT BE AN ISSUE BUT IT ALSO
BARES WATCHING. IT SHOULD BRING RAIN BACK INTO THE AREA BUT AT THIS
POINT IT LOOKS TO BE A PROGRESSIVE SYSTEM WHICH WILL LIMIT THE FLOOD
POTENTIAL. ADDITIONAL LOW PRESSURE SYSTEM MAY BRING RAIN INTO THE
AREA THROUGH MID WEEK.  MERCER

&&

.HYDROLOGY...SHOWERS WILL PERSIST TODAY BUT ADDITIONAL RAIN AMOUNTS
WILL NOT BE HYDROLOGICALLY SIGNIFICANT. THE SKOKOMISH RIVER WILL
REMAIN ABOVE FLOOD STAGE BUT GRADUALLY RECEDE TODAY...FALLING BELOW
FLOOD STAGE LATER TODAY OR THIS EVENING. REFER TO THE LATEST FLOOD
STATEMENT BULLETIN FOR THE MOST UP TO DATE INFORMATION.

WET WEATHER IS EXPECTED TO CONTINUE THROUGH THE UPCOMING WEEK. BUT
RAINFALL AMOUNTS ARE NOT EXPECTED TO DRIVE ANY RIVERS ABOVE FLOOD
STAGE. MERCER

&&

.AVIATION...AIR MASS UNSTABLE OVER WESTERN WASHINGTON TODAY AND
TONIGHT WITH SOUTHWESTERLY FLOW ALOFT.

NOTHING REALLY ORGANIZED MOVING THROUGH THE AREA TODAY BUT SATELLITE
IMAGERY SHOWS PLENTY OF SHOWERS EMBEDDED IN THE SOUTHWESTERLY FLOW
ALOFT OFFSHORE EXTENDING BACK TO NEAR 160W. IN GENERAL CEILINGS IN
THE 4000 TO 6000 FOOT RANGE LOWERING DOWN TO NEAR 2000 FEET WITH
VISIBILITIES 3-5SM BRIEFLY IN THE HEAVIER SHOWERS. THE AIR MASS IS
UNSTABLE ENOUGH FOR THE POSSIBILITY OF ISOLATED THUNDERSTORMS. THE
CHANCE FOR THUNDERSTORMS IS NOT HIGH ENOUGH TO INCLUDE IN THE TAFS.

KSEA...CEILINGS IN THE 4000-6000 FOOT RANGE DROPPING DOWN TO NEAR
2000 FEET IN THE HEAVIER SHOWERS LATE THIS MORNING INTO THE
AFTERNOON HOURS. SOUTHERLY WINDS 6 TO 10 KNOTS WITH BRIEF HIGHER
GUSTS IN THE VICINITY OF SHOWER ACTIVITY. FELTON

&&

.MARINE...SURFACE RIDGE BUILDING INTO WESTERN WASHINGTON TODAY BUT
WITH THE UNSTABLE AIR MASS OVER THE AREA STRONGER WINDS ALOFT
GETTING MIXED DOWN TO THE SURFACE THROUGH THE AFTERNOON HOURS. THIS
WILL KEEP SMALL CRAFT ADVISORIES UP THROUGHOUT THE DAY TODAY FOR THE
INLAND WATERS. SWELL OVER THE COASTAL WATERS STILL IN DOUBLE DIGITS
BUT WILL SUBSIDE BELOW 10 FEET TONIGHT. THE SMALL CRAFT FOR
HAZARDOUS SEAS REMAINS IN EFFECT TODAY.

SURFACE HIGH SHIFTING EAST LATER TONIGHT INTO FRIDAY WITH LIGHT
EASTERLY FLOW OVER THE WATERS. A 988 MB LOW WILL DEVELOP OFF THE
NORTHERN CALIFORNIA COAST AND MOVE INTO THE OREGON COASTAL WATERS ON
SATURDAY. THE LOW WILL CONTINUE TO MOVE NORTHEAST THROUGH THE INLAND
WATERS SATURDAY NIGHT. THE TRACK OF THE LOW WILL BE CRUCIAL IN HOW
MUCH WIND DEVELOPS OVER THE MARINE AREAS. AT THIS POINT GALE FORCE
WINDS ARE POSSIBLE SATURDAY NIGHT INTO SUNDAY MORNING OVER ALL OF
THE WATERS. THE WINDS WILL EASE ON SUNDAY AS ANOTHER WEAK RIDGE OF
HIGH PRESSURE BUILDS INTO THE AREA.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...FLOOD WARNING IN EFFECT FOR THE SKOKOMISH RIVER IN MASON
      COUNTY.

PZ...SMALL CRAFT ADVISORY IN EFFECT FOR HAZARDOUS SEAS
     FOR THE COASTAL WATERS.
     SMALL CRAFT ADVISORY FOR ROUGH BAR IN EFFECT UNTIL 8 PM
     TODAY.
     SMALL CRAFT ADVISORY TONIGHT INLAND WATERS AND
     ADMIRALTY INLET TODAY.
     SMALL CRAFT ADVISORY CENTRAL AND EASTERN STRAIT THIS
     AFTERNOON.

$$

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000
FXUS66 KSEW 230443
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
940 PM PDT WED OCT 22 2014

.SYNOPSIS...AN UPPER TROUGH WILL DIRECT SHOWERS INTO WESTERN
WASHINGTON THROUGH THURSDAY. THE SHOWERS WILL DECREASE THURSDAY
NIGHT. FRIDAY WILL BE A DRY DAY WITH WEAK HIGH PRESSURE AND OFFSHORE
FLOW. ANOTHER WEATHER SYSTEM WILL REACH THE AREA SATURDAY AFTERNOON
AND EVENING...WITH BLUSTERY WINDS DEVELOPING SATURDAY NIGHT.

&&

.SHORT TERM...AN UPPER TROUGH IS JUST OFFSHORE...SENDING SHOWERS
INTO THE REGION. A SURFACE TROUGH MOVED THROUGH WESTERN WA THIS
EVENING WITH LOCALLY HEAVY SHOWERS AND BLUSTERY WINDS...OLM-BLI WAS
+4MB AT 9PM. ANOTHER SURFACE TROUGH WILL REACH THE COAST AROUND 8AM
THU AND MOVE THROUGH THE INTERIOR OF WRN WA THRU MIDDAY. THE SHOWERS
WILL DECREASE THU NITE. TEMPORARY RIDGING MOVES OVER WRN WA FRIDAY
WITH LOW LEVEL OFFSHORE FLOW FOR A DRY DAY. ANOTHER SYSTEM MOVES
THRU THE AREA SATURDAY AFTERNOON AND NITE AND AS A SURFACE LOW MOVES
THROUGH WRN WA AND FILLS WINDS WILL BECOME BLUSTERY SAT NITE.

.LONG TERM...SHOWERS CAN BE EXPECTED BEHIND SATURDAY NIGHTS LOW
PRESSURE SYSTEM ON SUNDAY. BEYOND THAT TIME...MODELS ARE HAVING A
TOUGH TIME WITH THE DETAILS. THE ECMWF HAS A STORM TRACK TO THE
NORTH OF THE AREA WITH FRONTAL PASSAGES HERE THROUGH THE MIDDLE OF
NEXT WEEK. THE STORM TRACK ON THE GFS IS JUST TO THE SOUTH OF THE
AREA...STILL A WET ONE FOR WESTERN WASHINGTON BUT LESS WINDY. THE
CANADIAN SOLUTION IS CLOSER TO THE ECMWF. IN ANY CASE THE PATTERN
WILL REMAIN ACTIVE. ALBRECHT

&&

.HYDROLOGY...A FLOOD WARNING REMAINS IN EFFECT FOR THE SKOKOMISH
RIVER IN MASON COUNTY. THE SKOKOMISH AT POTLATCH CRESTED AROUND 17.2
FEET AT NOON TODAY. IT IS EXPECTED TO FALL BELOW FLOOD STAGE TONIGHT
AND GRADUALLY RECEDE THURSDAY THROUGH FRIDAY.

WET WEATHER IS EXPECTED TO CONTINUE THROUGH THE UPCOMING WEEK. BUT
RAINFALL AMOUNTS ARE NOT EXPECTED TO DRIVE ANY RIVERS ABOVE FLOOD
STAGE. ALBRECHT

&&

.AVIATION...COLD FRONT OVER THE CASCADES AT 04Z WILL CONTINUE TO
MOVE EAST. AIR MASS UNSTABLE WITH SOUTHWESTERLY FLOW ALOFT.

CEILINGS IN THE 4000 TO 6000 FOOT RANGE LOWERING DOWN TO NEAR 2000
FEET WITH VISIBILITIES 3-5SM IN SHOWERS. SHOWER ACTIVITY EASING UP
OVERNIGHT THEN INCREASING AGAIN THURSDAY MORNING INTO THE AFTERNOON
HOURS.

KSEA...CEILINGS NEAR 2000 FEET IN SHOWERS OTHERWISE CEILINGS IN THE
4000-6000 FOOT RANGE. SOUTHERLY WINDS 10-15 KNOTS WITH GUSTS NEAR 25
KNOTS UNTIL 06Z. FELTON

&&

.MARINE...COLD FRONT EAST OF THE WATERS THIS EVENING. PRESSURE RISES
BEHIND THE FRONT GIVING SMALL CRAFT ADVISORY SOUTHERLIES TO THE
INLAND WATERS INTO THE EARLY MORNING HOURS.

WEAK SURFACE RIDGE BUILDING OVER THE INLAND WATERS ON THURSDAY
SHIFTING EAST OF THE CASCADES ON FRIDAY. A 990 MB LOW WILL DEVELOP
OFF THE NORTHERN CALIFORNIA COAST AND MOVE INTO THE OREGON COASTAL
WATERS ON SATURDAY. THE LOW WILL CONTINUE TO MOVE NORTH INTO THE
INTERIOR OF WESTERN WASHINGTON SATURDAY NIGHT. THE TRACK OF THE LOW
WILL BE CRUCIAL IN HOW MUCH WIND DEVELOPS OVER THE MARINE AREAS. AT
THIS POINT GALE FORCE WINDS OR HIGHER ARE A GOOD POSSIBILITY
SATURDAY NIGHT INTO SUNDAY MORNING.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...FLOOD WARNING IN EFFECT FOR THE SKOKOMISH RIVER IN MASON
      COUNTY.

PZ...SMALL CRAFT ADVISORY IN EFFECT FOR HAZARDOUS IN EFFECT
     FOR THE COASTAL WATERS.
     SMALL CRAFT ADVISORY FOR ROUGH BAR IN EFFECT UNTIL 6 AM
     THURSDAY FOR THE GRAYS HARBOR BAR.
     SMALL CRAFT ADVISORY TONIGHT INLAND WATERS AND ADMIRALTY
     INLET.

&&

$$

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000
FXUS66 KSEW 230443
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
940 PM PDT WED OCT 22 2014

.SYNOPSIS...AN UPPER TROUGH WILL DIRECT SHOWERS INTO WESTERN
WASHINGTON THROUGH THURSDAY. THE SHOWERS WILL DECREASE THURSDAY
NIGHT. FRIDAY WILL BE A DRY DAY WITH WEAK HIGH PRESSURE AND OFFSHORE
FLOW. ANOTHER WEATHER SYSTEM WILL REACH THE AREA SATURDAY AFTERNOON
AND EVENING...WITH BLUSTERY WINDS DEVELOPING SATURDAY NIGHT.

&&

.SHORT TERM...AN UPPER TROUGH IS JUST OFFSHORE...SENDING SHOWERS
INTO THE REGION. A SURFACE TROUGH MOVED THROUGH WESTERN WA THIS
EVENING WITH LOCALLY HEAVY SHOWERS AND BLUSTERY WINDS...OLM-BLI WAS
+4MB AT 9PM. ANOTHER SURFACE TROUGH WILL REACH THE COAST AROUND 8AM
THU AND MOVE THROUGH THE INTERIOR OF WRN WA THRU MIDDAY. THE SHOWERS
WILL DECREASE THU NITE. TEMPORARY RIDGING MOVES OVER WRN WA FRIDAY
WITH LOW LEVEL OFFSHORE FLOW FOR A DRY DAY. ANOTHER SYSTEM MOVES
THRU THE AREA SATURDAY AFTERNOON AND NITE AND AS A SURFACE LOW MOVES
THROUGH WRN WA AND FILLS WINDS WILL BECOME BLUSTERY SAT NITE.

.LONG TERM...SHOWERS CAN BE EXPECTED BEHIND SATURDAY NIGHTS LOW
PRESSURE SYSTEM ON SUNDAY. BEYOND THAT TIME...MODELS ARE HAVING A
TOUGH TIME WITH THE DETAILS. THE ECMWF HAS A STORM TRACK TO THE
NORTH OF THE AREA WITH FRONTAL PASSAGES HERE THROUGH THE MIDDLE OF
NEXT WEEK. THE STORM TRACK ON THE GFS IS JUST TO THE SOUTH OF THE
AREA...STILL A WET ONE FOR WESTERN WASHINGTON BUT LESS WINDY. THE
CANADIAN SOLUTION IS CLOSER TO THE ECMWF. IN ANY CASE THE PATTERN
WILL REMAIN ACTIVE. ALBRECHT

&&

.HYDROLOGY...A FLOOD WARNING REMAINS IN EFFECT FOR THE SKOKOMISH
RIVER IN MASON COUNTY. THE SKOKOMISH AT POTLATCH CRESTED AROUND 17.2
FEET AT NOON TODAY. IT IS EXPECTED TO FALL BELOW FLOOD STAGE TONIGHT
AND GRADUALLY RECEDE THURSDAY THROUGH FRIDAY.

WET WEATHER IS EXPECTED TO CONTINUE THROUGH THE UPCOMING WEEK. BUT
RAINFALL AMOUNTS ARE NOT EXPECTED TO DRIVE ANY RIVERS ABOVE FLOOD
STAGE. ALBRECHT

&&

.AVIATION...COLD FRONT OVER THE CASCADES AT 04Z WILL CONTINUE TO
MOVE EAST. AIR MASS UNSTABLE WITH SOUTHWESTERLY FLOW ALOFT.

CEILINGS IN THE 4000 TO 6000 FOOT RANGE LOWERING DOWN TO NEAR 2000
FEET WITH VISIBILITIES 3-5SM IN SHOWERS. SHOWER ACTIVITY EASING UP
OVERNIGHT THEN INCREASING AGAIN THURSDAY MORNING INTO THE AFTERNOON
HOURS.

KSEA...CEILINGS NEAR 2000 FEET IN SHOWERS OTHERWISE CEILINGS IN THE
4000-6000 FOOT RANGE. SOUTHERLY WINDS 10-15 KNOTS WITH GUSTS NEAR 25
KNOTS UNTIL 06Z. FELTON

&&

.MARINE...COLD FRONT EAST OF THE WATERS THIS EVENING. PRESSURE RISES
BEHIND THE FRONT GIVING SMALL CRAFT ADVISORY SOUTHERLIES TO THE
INLAND WATERS INTO THE EARLY MORNING HOURS.

WEAK SURFACE RIDGE BUILDING OVER THE INLAND WATERS ON THURSDAY
SHIFTING EAST OF THE CASCADES ON FRIDAY. A 990 MB LOW WILL DEVELOP
OFF THE NORTHERN CALIFORNIA COAST AND MOVE INTO THE OREGON COASTAL
WATERS ON SATURDAY. THE LOW WILL CONTINUE TO MOVE NORTH INTO THE
INTERIOR OF WESTERN WASHINGTON SATURDAY NIGHT. THE TRACK OF THE LOW
WILL BE CRUCIAL IN HOW MUCH WIND DEVELOPS OVER THE MARINE AREAS. AT
THIS POINT GALE FORCE WINDS OR HIGHER ARE A GOOD POSSIBILITY
SATURDAY NIGHT INTO SUNDAY MORNING.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...FLOOD WARNING IN EFFECT FOR THE SKOKOMISH RIVER IN MASON
      COUNTY.

PZ...SMALL CRAFT ADVISORY IN EFFECT FOR HAZARDOUS IN EFFECT
     FOR THE COASTAL WATERS.
     SMALL CRAFT ADVISORY FOR ROUGH BAR IN EFFECT UNTIL 6 AM
     THURSDAY FOR THE GRAYS HARBOR BAR.
     SMALL CRAFT ADVISORY TONIGHT INLAND WATERS AND ADMIRALTY
     INLET.

&&

$$

WWW.WEATHER.GOV/SEATTLE

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000
FXUS66 KSEW 222252 CCA
AFDSEW

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SEATTLE WA
352 PM PDT WED OCT 22 2014

CORRECTED MINOR TYPO IN THE SECOND PARAGRAPH OF THE MARINE SEGMENT.

.SYNOPSIS...DISTURBANCES MOVING AROUND AN UPPER TROUGH OFFSHORE WILL
CONTINUE THROUGH THURSDAY. THE AIR MASS IS UNSTABLE...SO THERE WILL
BE A CHANCE OF THUNDERSTORMS ON THE COAST TONIGHT AND THROUGHOUT THE
AREA ON THURSDAY. SHOWER ACTIVITY WILL DIMINISH THURSDAY NIGHT AND
FRIDAY MORNING. WHILE IT WILL REMAIN RATHER CLOUDY FRIDAY
AFTERNOON...A BRIEF AND WEAK RIDGE OF HIGH PRESSURE ALOFT COMBINED
WITH LOW LEVEL OFFSHORE FLOW WILL GIVE DRIER WEATHER. A LOW PRESSURE
SYSTEM DEVELOPING OFF THE OREGON COAST WILL MOVE ACROSS THE AREA
LATE SATURDAY OR SATURDAY NIGHT. ACTIVE WEATHER WILL CONTINUE INTO
NEXT WEEK.

&&

.SHORT TERM...SATELLITE IMAGERY AND RADARS SHOW THE FRONT THAT MOVED
ACROSS THE AREA EARLY THIS MORNING IS NOW NEARLY STATIONARY FROM THE
CASCADES INTO NORTHWESTERN OREGON. A BROAD AND RATHER DEEP UPPER
LEVEL TROUGH IS CENTERED AROUND 145W LONGITUDE. UPPER LEVEL
DISTURBANCES ARE ROTATING AROUND THIS TROUGH AND ARE RIDING
NORTHEASTWARD ALONG THE FRONT ACROSS THE PACIFIC NORTHWEST. THE
FIRST DISTURBANCE ENHANCED PRECIPITATION TODAY AS IT MOVED NORTHEAST
ACROSS THE AREA. THE GFS SHOWS ANOTHER WAVE NOW OVER THE OREGON
OFFSHORE WATERS SHIFTING NE ACROSS THE AREA TONIGHT. THE AXIS OF THE
HEAVIEST PRECIPITATION AMOUNTS WILL LIKELY BE SHIFTED ABOUT 50 TO
100 MILES FARTHER TO THE SOUTH AND EAST OF WHERE THE RAIN WAS SEEN
TODAY. YET ANOTHER DISTURBANCE...THIS ONE NOW SEEN AS WHAT APPEARS
TO BE A DEVELOPING INSTANT OCCLUSION NORTH OF THE FRONT NEAR
135W...APPEARS THAT IT WILL MOVE ACROSS THE AREA ON THURSDAY.

THUNDERSTORM ACTIVITY THAT WAS SEEN EARLIER TODAY OVER THE COASTAL
WATERS HAS MAINLY MOVED INTO VANCOUVER ISLAND...BUT SOME ISOLATED
LIGHTNING STRIKES CAN STILL BE SEEN OVER THE OFFSHORE WATERS. SOME
THUNDERSTORM ACTIVITY CAN BE EXPECTED OVER THE COASTAL WATERS
TONIGHT AND THERE IS A CHANCE THAT A FEW LIGHTNING STRIKES WILL BE
SEEN ALONG THE COAST AND IN THE WESTERN OLYMPIC MOUNTAINS. THE AIR
MASS IS EXPECTED TO BE A BIT MORE UNSTABLE OVER THE INTERIOR
THURSDAY AFTERNOON AS THE INSTANT OCCLUSION MOVES NE ACROSS THE
AREA. LIFTED INDEX VALUES FALL TO AROUND -2.1 AND CAPES RISE TO
ABOUT 500 J/KG IN THE SEATTLE AREA 21Z THU PER THE NAM12 AND THE GFS
IS SLIGHTLY MORE UNSTABLE. SHOWERS WITH A CHANCE OF THUNDERSTORMS
WILL BE IN THE FORECAST FOR THE ENTIRE AREA ON THU.

SHOWERS DIMINISH THU NIGHT AND COME TO AN END FRI MORNING ACROSS
MUCH OF THE AREA AS A DEEP LOW DEVELOPS OFF THE NORTHERN CALIFORNIA
AND SOUTHERN OREGON OFFSHORE WATERS. THIS LOW APPEARS TO BE
DEVELOPING IN RESPONSE TO A SYSTEM DROPPING SE FROM THE BERING SEA
AS IT PHASES SOMEWHAT WITH THE REMAINS OF ANA NW OF HAWAII. THE
LATEST NAM12 AND GFS SOLUTIONS SHOW THE LOW REACHING ITS MAXIMUM
DEPTH AT AROUND 985 MB OFF THE CENTRAL OREGON COAST WHILE THE
CANADIAN AND ECMWF SOLUTIONS ARE 5-10 MB DEEPER. OFFSHORE FLOW AND
SHORT WAVE RIDGING ALOFT MAY BRING A RATHER DRY PERIOD...ALBEIT
CLOUDY...TO THE AREA FROM LATE FRIDAY MORNING INTO EARLY FRIDAY
EVENING.

THE LOW QUICKLY BECOMES VERTICALLY STACKED IN ALL OF THE MODELS OFF
THE OREGON COAST...THEN IT MATURES...MOVES NORTHEAST...AND GRADUALLY
DECAYS AS IT MOVES NE ACROSS OUR AREA SAT EVENING. DEPENDING ON THE
DEPTH AND TRACK OF THE LOW...IT MAY GET WINDY OVER PORTIONS OF
WESTERN WASHINGTON LATER SATURDAY INTO SATURDAY NIGHT. BUT WITH THE
LOW DECAYING AND WIND FIELD EXPANDING...EXPECT THE THREAT OF HIGH
WIND IN THE FORECAST AREA TO BE BELOW 25 PERCENT. SOME MODEL
SOLUTIONS...LIKE THE 12Z CANADIAN SOLUTION...KEEP THE TRACK OF THE
LOW SOUTH OF THE FORECAST AREA. THIS IS NOT UNREASONABLE GIVEN THE
GENERAL SPLIT FLOW PATTERN BEING SEEN OVER THE WESTERN U.S. OF LATE.

TEMPERATURES WILL BE SEASONABLE FOR THIS TIME OF YEAR AND IT WILL
REMAIN RATHER CLOUDY AS WE GO THROUGH THE NEXT SEVERAL DAYS. ALBRECHT

.LONG TERM...SHOWERS CAN BE EXPECTED BEHIND SATURDAY NIGHTS LOW
PRESSURE SYSTEM ON SUNDAY. BEYOND THAT TIME...MODELS ARE HAVING A
TOUGH TIME WITH THE DETAILS. THE ECMWF HAS A STORM TRACK TO THE
NORTH OF THE AREA WITH FRONTAL PASSAGES HERE THROUGH THE MIDDLE OF
NEXT WEEK. THE STORM TRACK ON THE GFS IS JUST TO THE SOUTH OF THE
AREA...STILL A WET ONE FOR WESTERN WASHINGTON BUT LESS WINDY. THE
CANADIAN SOLUTION IS CLOSER TO THE ECMWF. IN ANY CASE THE PATTERN
WILL REMAIN ACTIVE. ALBRECHT

&&

.HYDROLOGY...A FLOOD WARNING REMAINS IN EFFECT FOR THE SKOKOMISH
RIVER IN MASON COUNTY. THE SKOKOMISH AT POTLATCH CRESTED AROUND 17.2
FEET AT NOON TODAY. IT IS EXPECTED TO FALL BELOW FLOOD STAGE TONIGHT
AND GRADUALLY RECEDE THURSDAY THROUGH FRIDAY.

WET WEATHER IS EXPECTED TO CONTINUE THROUGH THE UPCOMING WEEK. BUT
RAINFALL AMOUNTS ARE NOT EXPECTED TO DRIVE ANY RIVERS ABOVE FLOOD
STAGE. ALBRECHT

&&

.AVIATION...A SLOW-MOVING CDFNT OVER THE INTERIOR IS EXPECTED TO BE
E OF THE CASCADES BY 0600 UTC THU. IT NOW APPEARS THAT THE UNSTABLE
AIR MASS WILL REMAIN OVER THE COASTAL WATERS THRU TONIGHT.
MEANWHILE...STRONG SW FLOW ALOFT WILL CONT OVER THE REGION THRU
TONIGHT. THE LOW LEVEL FLOW WILL REMAIN SLY.

EXPECT AREAS OF CIGS AND VSBYS IN THE 1-3K FT AND 3-5SM RANGE...
RESPECTIVELY...THRU TONIGHT. HOWEVER HEAVY PRECIP WILL RESULT IN
OCNL IFR CIGS/VSBYS.

KSEA...CIGS HAVE LIFTED INTO THE VFR CATEGORY BUT OCNLY CIGS IN THE
2-3K FT RANGE CAN BE EXPECTED THRU PART OF TONIGHT. CIGS NEAR 2K FT
MAY BECOME PREDOMINANT LATE TONIGHT OR EARLY THU.

&&

.MARINE...
A 1001 MB LOW DEVELOPED OVER THE OREGON COASTAL WATERS THIS
AFTERNOON AND THIS HAS SLOWED DOWN THE COLD FRONT OVER THE PUGET
SOUND REGION. THE COLD FRONT SHOULD BE E OF THE CASCADES BY LATE
THIS EVENING. WILL NEED TO WATCH FOR THE POSSIBILITY OF A BURST OF
SOUTHERLY WINDS NEAR 25 KNOTS OVER THE WATERS FROM POINT GRENVILLE
TO CAPE SHOALWATER OUT TO 60 NM LATE THIS AFTERNOON THROUGH THIS
EVENING AS THE LOW MOVES OFF TO THE NE.

BEYOND THIS AFTERNOON...NUMERICAL WEATHER MODELS WERE NOT IN GOOD
AGREEMENT WITH THE TRACK...TIMING...AND STRENGTH OF THE LOW THAT IS
EXPECTED THE END OF THIS WEEK. DEPENDING ON WHICH MODEL IS
CORRECT...THIS SYSTEM COULD PRODUCE ANYWHERE FROM HIGH END GALE OR
LOW END STORM FORCE WINDS OVER PARTS OF THE AREA TO INCONSEQUENTIAL
WIND SPEEDS. THE FORECAST REFLECTS THE CONSENSUS. THUS ANTICIPATE
GALE FORCE WINDS OVER MUCH OF THE WATERS SATURDAY NIGHT.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WARNING IN EFFECT FOR THE SKOKOMISH RIVER IN MASON
      COUNTY.

PZ...SMALL CRAFT ADVISORY IN EFFECT FOR HAZARDOUS IN EFFECT FOR
      THE COASTAL WATERS AND WEST ENTRANCE TO THE STRAIT OF JUAN DE
      FUCA.
     SMALL CRAFT ADVISORY FOR ROUGH BAR IN EFFECT UNTIL 6 AM
      THURSDAY FOR THE GRAYS HARBOR 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 222252 CCA
AFDSEW

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SEATTLE WA
352 PM PDT WED OCT 22 2014

CORRECTED MINOR TYPO IN THE SECOND PARAGRAPH OF THE MARINE SEGMENT.

.SYNOPSIS...DISTURBANCES MOVING AROUND AN UPPER TROUGH OFFSHORE WILL
CONTINUE THROUGH THURSDAY. THE AIR MASS IS UNSTABLE...SO THERE WILL
BE A CHANCE OF THUNDERSTORMS ON THE COAST TONIGHT AND THROUGHOUT THE
AREA ON THURSDAY. SHOWER ACTIVITY WILL DIMINISH THURSDAY NIGHT AND
FRIDAY MORNING. WHILE IT WILL REMAIN RATHER CLOUDY FRIDAY
AFTERNOON...A BRIEF AND WEAK RIDGE OF HIGH PRESSURE ALOFT COMBINED
WITH LOW LEVEL OFFSHORE FLOW WILL GIVE DRIER WEATHER. A LOW PRESSURE
SYSTEM DEVELOPING OFF THE OREGON COAST WILL MOVE ACROSS THE AREA
LATE SATURDAY OR SATURDAY NIGHT. ACTIVE WEATHER WILL CONTINUE INTO
NEXT WEEK.

&&

.SHORT TERM...SATELLITE IMAGERY AND RADARS SHOW THE FRONT THAT MOVED
ACROSS THE AREA EARLY THIS MORNING IS NOW NEARLY STATIONARY FROM THE
CASCADES INTO NORTHWESTERN OREGON. A BROAD AND RATHER DEEP UPPER
LEVEL TROUGH IS CENTERED AROUND 145W LONGITUDE. UPPER LEVEL
DISTURBANCES ARE ROTATING AROUND THIS TROUGH AND ARE RIDING
NORTHEASTWARD ALONG THE FRONT ACROSS THE PACIFIC NORTHWEST. THE
FIRST DISTURBANCE ENHANCED PRECIPITATION TODAY AS IT MOVED NORTHEAST
ACROSS THE AREA. THE GFS SHOWS ANOTHER WAVE NOW OVER THE OREGON
OFFSHORE WATERS SHIFTING NE ACROSS THE AREA TONIGHT. THE AXIS OF THE
HEAVIEST PRECIPITATION AMOUNTS WILL LIKELY BE SHIFTED ABOUT 50 TO
100 MILES FARTHER TO THE SOUTH AND EAST OF WHERE THE RAIN WAS SEEN
TODAY. YET ANOTHER DISTURBANCE...THIS ONE NOW SEEN AS WHAT APPEARS
TO BE A DEVELOPING INSTANT OCCLUSION NORTH OF THE FRONT NEAR
135W...APPEARS THAT IT WILL MOVE ACROSS THE AREA ON THURSDAY.

THUNDERSTORM ACTIVITY THAT WAS SEEN EARLIER TODAY OVER THE COASTAL
WATERS HAS MAINLY MOVED INTO VANCOUVER ISLAND...BUT SOME ISOLATED
LIGHTNING STRIKES CAN STILL BE SEEN OVER THE OFFSHORE WATERS. SOME
THUNDERSTORM ACTIVITY CAN BE EXPECTED OVER THE COASTAL WATERS
TONIGHT AND THERE IS A CHANCE THAT A FEW LIGHTNING STRIKES WILL BE
SEEN ALONG THE COAST AND IN THE WESTERN OLYMPIC MOUNTAINS. THE AIR
MASS IS EXPECTED TO BE A BIT MORE UNSTABLE OVER THE INTERIOR
THURSDAY AFTERNOON AS THE INSTANT OCCLUSION MOVES NE ACROSS THE
AREA. LIFTED INDEX VALUES FALL TO AROUND -2.1 AND CAPES RISE TO
ABOUT 500 J/KG IN THE SEATTLE AREA 21Z THU PER THE NAM12 AND THE GFS
IS SLIGHTLY MORE UNSTABLE. SHOWERS WITH A CHANCE OF THUNDERSTORMS
WILL BE IN THE FORECAST FOR THE ENTIRE AREA ON THU.

SHOWERS DIMINISH THU NIGHT AND COME TO AN END FRI MORNING ACROSS
MUCH OF THE AREA AS A DEEP LOW DEVELOPS OFF THE NORTHERN CALIFORNIA
AND SOUTHERN OREGON OFFSHORE WATERS. THIS LOW APPEARS TO BE
DEVELOPING IN RESPONSE TO A SYSTEM DROPPING SE FROM THE BERING SEA
AS IT PHASES SOMEWHAT WITH THE REMAINS OF ANA NW OF HAWAII. THE
LATEST NAM12 AND GFS SOLUTIONS SHOW THE LOW REACHING ITS MAXIMUM
DEPTH AT AROUND 985 MB OFF THE CENTRAL OREGON COAST WHILE THE
CANADIAN AND ECMWF SOLUTIONS ARE 5-10 MB DEEPER. OFFSHORE FLOW AND
SHORT WAVE RIDGING ALOFT MAY BRING A RATHER DRY PERIOD...ALBEIT
CLOUDY...TO THE AREA FROM LATE FRIDAY MORNING INTO EARLY FRIDAY
EVENING.

THE LOW QUICKLY BECOMES VERTICALLY STACKED IN ALL OF THE MODELS OFF
THE OREGON COAST...THEN IT MATURES...MOVES NORTHEAST...AND GRADUALLY
DECAYS AS IT MOVES NE ACROSS OUR AREA SAT EVENING. DEPENDING ON THE
DEPTH AND TRACK OF THE LOW...IT MAY GET WINDY OVER PORTIONS OF
WESTERN WASHINGTON LATER SATURDAY INTO SATURDAY NIGHT. BUT WITH THE
LOW DECAYING AND WIND FIELD EXPANDING...EXPECT THE THREAT OF HIGH
WIND IN THE FORECAST AREA TO BE BELOW 25 PERCENT. SOME MODEL
SOLUTIONS...LIKE THE 12Z CANADIAN SOLUTION...KEEP THE TRACK OF THE
LOW SOUTH OF THE FORECAST AREA. THIS IS NOT UNREASONABLE GIVEN THE
GENERAL SPLIT FLOW PATTERN BEING SEEN OVER THE WESTERN U.S. OF LATE.

TEMPERATURES WILL BE SEASONABLE FOR THIS TIME OF YEAR AND IT WILL
REMAIN RATHER CLOUDY AS WE GO THROUGH THE NEXT SEVERAL DAYS. ALBRECHT

.LONG TERM...SHOWERS CAN BE EXPECTED BEHIND SATURDAY NIGHTS LOW
PRESSURE SYSTEM ON SUNDAY. BEYOND THAT TIME...MODELS ARE HAVING A
TOUGH TIME WITH THE DETAILS. THE ECMWF HAS A STORM TRACK TO THE
NORTH OF THE AREA WITH FRONTAL PASSAGES HERE THROUGH THE MIDDLE OF
NEXT WEEK. THE STORM TRACK ON THE GFS IS JUST TO THE SOUTH OF THE
AREA...STILL A WET ONE FOR WESTERN WASHINGTON BUT LESS WINDY. THE
CANADIAN SOLUTION IS CLOSER TO THE ECMWF. IN ANY CASE THE PATTERN
WILL REMAIN ACTIVE. ALBRECHT

&&

.HYDROLOGY...A FLOOD WARNING REMAINS IN EFFECT FOR THE SKOKOMISH
RIVER IN MASON COUNTY. THE SKOKOMISH AT POTLATCH CRESTED AROUND 17.2
FEET AT NOON TODAY. IT IS EXPECTED TO FALL BELOW FLOOD STAGE TONIGHT
AND GRADUALLY RECEDE THURSDAY THROUGH FRIDAY.

WET WEATHER IS EXPECTED TO CONTINUE THROUGH THE UPCOMING WEEK. BUT
RAINFALL AMOUNTS ARE NOT EXPECTED TO DRIVE ANY RIVERS ABOVE FLOOD
STAGE. ALBRECHT

&&

.AVIATION...A SLOW-MOVING CDFNT OVER THE INTERIOR IS EXPECTED TO BE
E OF THE CASCADES BY 0600 UTC THU. IT NOW APPEARS THAT THE UNSTABLE
AIR MASS WILL REMAIN OVER THE COASTAL WATERS THRU TONIGHT.
MEANWHILE...STRONG SW FLOW ALOFT WILL CONT OVER THE REGION THRU
TONIGHT. THE LOW LEVEL FLOW WILL REMAIN SLY.

EXPECT AREAS OF CIGS AND VSBYS IN THE 1-3K FT AND 3-5SM RANGE...
RESPECTIVELY...THRU TONIGHT. HOWEVER HEAVY PRECIP WILL RESULT IN
OCNL IFR CIGS/VSBYS.

KSEA...CIGS HAVE LIFTED INTO THE VFR CATEGORY BUT OCNLY CIGS IN THE
2-3K FT RANGE CAN BE EXPECTED THRU PART OF TONIGHT. CIGS NEAR 2K FT
MAY BECOME PREDOMINANT LATE TONIGHT OR EARLY THU.

&&

.MARINE...
A 1001 MB LOW DEVELOPED OVER THE OREGON COASTAL WATERS THIS
AFTERNOON AND THIS HAS SLOWED DOWN THE COLD FRONT OVER THE PUGET
SOUND REGION. THE COLD FRONT SHOULD BE E OF THE CASCADES BY LATE
THIS EVENING. WILL NEED TO WATCH FOR THE POSSIBILITY OF A BURST OF
SOUTHERLY WINDS NEAR 25 KNOTS OVER THE WATERS FROM POINT GRENVILLE
TO CAPE SHOALWATER OUT TO 60 NM LATE THIS AFTERNOON THROUGH THIS
EVENING AS THE LOW MOVES OFF TO THE NE.

BEYOND THIS AFTERNOON...NUMERICAL WEATHER MODELS WERE NOT IN GOOD
AGREEMENT WITH THE TRACK...TIMING...AND STRENGTH OF THE LOW THAT IS
EXPECTED THE END OF THIS WEEK. DEPENDING ON WHICH MODEL IS
CORRECT...THIS SYSTEM COULD PRODUCE ANYWHERE FROM HIGH END GALE OR
LOW END STORM FORCE WINDS OVER PARTS OF THE AREA TO INCONSEQUENTIAL
WIND SPEEDS. THE FORECAST REFLECTS THE CONSENSUS. THUS ANTICIPATE
GALE FORCE WINDS OVER MUCH OF THE WATERS SATURDAY NIGHT.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WARNING IN EFFECT FOR THE SKOKOMISH RIVER IN MASON
      COUNTY.

PZ...SMALL CRAFT ADVISORY IN EFFECT FOR HAZARDOUS IN EFFECT FOR
      THE COASTAL WATERS AND WEST ENTRANCE TO THE STRAIT OF JUAN DE
      FUCA.
     SMALL CRAFT ADVISORY FOR ROUGH BAR IN EFFECT UNTIL 6 AM
      THURSDAY FOR THE GRAYS HARBOR 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 222233
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
333 PM PDT WED OCT 22 2014

.SYNOPSIS...DISTURBANCES MOVING AROUND AN UPPER TROUGH OFFSHORE WILL
CONTINUE THROUGH THURSDAY. THE AIR MASS IS UNSTABLE...SO THERE WILL
BE A CHANCE OF THUNDERSTORMS ON THE COAST TONIGHT AND THROUGHOUT THE
AREA ON THURSDAY. SHOWER ACTIVITY WILL DIMINISH THURSDAY NIGHT AND
FRIDAY MORNING. WHILE IT WILL REMAIN RATHER CLOUDY FRIDAY
AFTERNOON...A BRIEF AND WEAK RIDGE OF HIGH PRESSURE ALOFT COMBINED
WITH LOW LEVEL OFFSHORE FLOW WILL GIVE DRIER WEATHER. A LOW PRESSURE
SYSTEM DEVELOPING OFF THE OREGON COAST WILL MOVE ACROSS THE AREA
LATE SATURDAY OR SATURDAY NIGHT. ACTIVE WEATHER WILL CONTINUE INTO
NEXT WEEK.

&&

.SHORT TERM...SATELLITE IMAGERY AND RADARS SHOW THE FRONT THAT MOVED
ACROSS THE AREA EARLY THIS MORNING IS NOW NEARLY STATIONARY FROM THE
CASCADES INTO NORTHWESTERN OREGON. A BROAD AND RATHER DEEP UPPER
LEVEL TROUGH IS CENTERED AROUND 145W LONGITUDE. UPPER LEVEL
DISTURBANCES ARE ROTATING AROUND THIS TROUGH AND ARE RIDING
NORTHEASTWARD ALONG THE FRONT ACROSS THE PACIFIC NORTHWEST. THE
FIRST DISTURBANCE ENHANCED PRECIPITATION TODAY AS IT MOVED NORTHEAST
ACROSS THE AREA. THE GFS SHOWS ANOTHER WAVE NOW OVER THE OREGON
OFFSHORE WATERS SHIFTING NE ACROSS THE AREA TONIGHT. THE AXIS OF THE
HEAVIEST PRECIPITATION AMOUNTS WILL LIKELY BE SHIFTED ABOUT 50 TO
100 MILES FARTHER TO THE SOUTH AND EAST OF WHERE THE RAIN WAS SEEN
TODAY. YET ANOTHER DISTURBANCE...THIS ONE NOW SEEN AS WHAT APPEARS
TO BE A DEVELOPING INSTANT OCCLUSION NORTH OF THE FRONT NEAR
135W...APPEARS THAT IT WILL MOVE ACROSS THE AREA ON THURSDAY.

THUNDERSTORM ACTIVITY THAT WAS SEEN EARLIER TODAY OVER THE COASTAL
WATERS HAS MAINLY MOVED INTO VANCOUVER ISLAND...BUT SOME ISOLATED
LIGHTNING STRIKES CAN STILL BE SEEN OVER THE OFFSHORE WATERS. SOME
THUNDERSTORM ACTIVITY CAN BE EXPECTED OVER THE COASTAL WATERS
TONIGHT AND THERE IS A CHANCE THAT A FEW LIGHTNING STRIKES WILL BE
SEEN ALONG THE COAST AND IN THE WESTERN OLYMPIC MOUNTAINS. THE AIR
MASS IS EXPECTED TO BE A BIT MORE UNSTABLE OVER THE INTERIOR
THURSDAY AFTERNOON AS THE INSTANT OCCLUSION MOVES NE ACROSS THE
AREA. LIFTED INDEX VALUES FALL TO AROUND -2.1 AND CAPES RISE TO
ABOUT 500 J/KG IN THE SEATTLE AREA 21Z THU PER THE NAM12 AND THE GFS
IS SLIGHTLY MORE UNSTABLE. SHOWERS WITH A CHANCE OF THUNDERSTORMS
WILL BE IN THE FORECAST FOR THE ENTIRE AREA ON THU.

SHOWERS DIMINISH THU NIGHT AND COME TO AN END FRI MORNING ACROSS
MUCH OF THE AREA AS A DEEP LOW DEVELOPS OFF THE NORTHERN CALIFORNIA
AND SOUTHERN OREGON OFFSHORE WATERS. THIS LOW APPEARS TO BE
DEVELOPING IN RESPONSE TO A SYSTEM DROPPING SE FROM THE BERING SEA
AS IT PHASES SOMEWHAT WITH THE REMAINS OF ANA NW OF HAWAII. THE
LATEST NAM12 AND GFS SOLUTIONS SHOW THE LOW REACHING ITS MAXIMUM
DEPTH AT AROUND 985 MB OFF THE CENTRAL OREGON COAST WHILE THE
CANADIAN AND ECMWF SOLUTIONS ARE 5-10 MB DEEPER. OFFSHORE FLOW AND
SHORT WAVE RIDGING ALOFT MAY BRING A RATHER DRY PERIOD...ALBEIT
CLOUDY...TO THE AREA FROM LATE FRIDAY MORNING INTO EARLY FRIDAY
EVENING.

THE LOW QUICKLY BECOMES VERTICALLY STACKED IN ALL OF THE MODELS OFF
THE OREGON COAST...THEN IT MATURES...MOVES NORTHEAST...AND GRADUALLY
DECAYS AS IT MOVES NE ACROSS OUR AREA SAT EVENING. DEPENDING ON THE
DEPTH AND TRACK OF THE LOW...IT MAY GET WINDY OVER PORTIONS OF
WESTERN WASHINGTON LATER SATURDAY INTO SATURDAY NIGHT. BUT WITH THE
LOW DECAYING AND WIND FIELD EXPANDING...EXPECT THE THREAT OF HIGH
WIND IN THE FORECAST AREA TO BE BELOW 25 PERCENT. SOME MODEL
SOLUTIONS...LIKE THE 12Z CANADIAN SOLUTION...KEEP THE TRACK OF THE
LOW SOUTH OF THE FORECAST AREA. THIS IS NOT UNREASONABLE GIVEN THE
GENERAL SPLIT FLOW PATTERN BEING SEEN OVER THE WESTERN U.S. OF LATE.

TEMPERATURES WILL BE SEASONABLE FOR THIS TIME OF YEAR AND IT WILL
REMAIN RATHER CLOUDY AS WE GO THROUGH THE NEXT SEVERAL DAYS. ALBRECHT

.LONG TERM...SHOWERS CAN BE EXPECTED BEHIND SATURDAY NIGHTS LOW
PRESSURE SYSTEM ON SUNDAY. BEYOND THAT TIME...MODELS ARE HAVING A
TOUGH TIME WITH THE DETAILS. THE ECMWF HAS A STORM TRACK TO THE
NORTH OF THE AREA WITH FRONTAL PASSAGES HERE THROUGH THE MIDDLE OF
NEXT WEEK. THE STORM TRACK ON THE GFS IS JUST TO THE SOUTH OF THE
AREA...STILL A WET ONE FOR WESTERN WASHINGTON BUT LESS WINDY. THE
CANADIAN SOLUTION IS CLOSER TO THE ECMWF. IN ANY CASE THE PATTERN
WILL REMAIN ACTIVE. ALBRECHT

&&

.HYDROLOGY...A FLOOD WARNING REMAINS IN EFFECT FOR THE SKOKOMISH
RIVER IN MASON COUNTY. THE SKOKOMISH AT POTLATCH CRESTED AROUND 17.2
FEET AT NOON TODAY. IT IS EXPECTED TO FALL BELOW FLOOD STAGE TONIGHT
AND GRADUALLY RECEDE THURSDAY THROUGH FRIDAY.

WET WEATHER IS EXPECTED TO CONTINUE THROUGH THE UPCOMING WEEK. BUT
RAINFALL AMOUNTS ARE NOT EXPECTED TO DRIVE ANY RIVERS ABOVE FLOOD
STAGE. ALBRECHT

&&

.AVIATION...A SLOW-MOVING CDFNT OVER THE INTERIOR IS EXPECTED TO BE
E OF THE CASCADES BY 0600 UTC THU. IT NOW APPEARS THAT THE UNSTABLE
AIR MASS WILL REMAIN OVER THE COASTAL WATERS THRU TONIGHT.
MEANWHILE...STRONG SW FLOW ALOFT WILL CONT OVER THE REGION THRU
TONIGHT. THE LOW LEVEL FLOW WILL REMAIN SLY.

EXPECT AREAS OF CIGS AND VSBYS IN THE 1-3K FT AND 3-5SM RANGE...
RESPECTIVELY...THRU TONIGHT. HOWEVER HEAVY PRECIP WILL RESULT IN
OCNL IFR CIGS/VSBYS.

KSEA...CIGS HAVE LIFTED INTO THE VFR CATEGORY BUT OCNLY CIGS IN THE
2-3K FT RANGE CAN BE EXPECTED THRU PART OF TONIGHT. CIGS NEAR 2K FT
MAY BECOME PREDOMINANT LATE TONIGHT OR EARLY THU.

&&

.MARINE...
A 1001 MB LOW DEVELOPED OVER THE OREGON COASTAL WATERS THIS
AFTERNOON AND THIS HAS SLOWED DOWN THE COLD FRONT OVER THE PUGET
SOUND REGION. THE COLD FRONT SHOULD BE E OF THE CASCADES BY LATE
THIS EVENING. WILL NEED TO WATCH FOR THE POSSIBILITY OF A BURST OF
SOUTHERLY WINDS NEAR 25 KNOTS OVER THE WATERS FROM POINT GRENVILLE
TO CAPE SHOALWATER OUT TO 60 NM LATE THIS AFTERNOON THROUGH THIS
EVENING AS THE LOW MOVES OFF TO THE NE.

BEYOND THIS AFTERNOON...NUMERICAL WEATHER MODELS WERE NOT IN GOOD
AGREEMENT WITH THE TRACK...TIMING...AND STRENGTH OF THE LOW THAT IS
EXPECTED THE END OF THIS WEEK. DEPENDING ON WHICH MODEL IS
CORRECT...THIS SYSTEM COULD PRODUCE ANYWHERE FROM HIGH END GALE OR
LOW END STORM FORCE WINDS OVER PARTS OF THE AREA OR INCONSEQUENTIAL
WIND SPEEDS. THE FORECAST REFLECTS THE CONSENSUS. THUS ANTICIPATE
GALE FORCE WINDS OVER MUCH OF THE WATERS SATURDAY NIGHT.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WARNING IN EFFECT FOR THE SKOKOMISH RIVER IN MASON
      COUNTY.

PZ...SMALL CRAFT ADVISORY IN EFFECT FOR HAZARDOUS IN EFFECT FOR
      THE COASTAL WATERS AND WEST ENTRANCE TO THE STRAIT OF JUAN DE
      FUCA.
     SMALL CRAFT ADVISORY FOR ROUGH BAR IN EFFECT UNTIL 6 AM
      THURSDAY FOR THE GRAYS HARBOR 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 221624
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
925 AM PDT WED OCT 22 2014

.SYNOPSIS...THE FRONTAL SYSTEM THAT PRODUCED LOCALLY HEAVY RAIN AND
WINDY CONDITIONS OVERNIGHT IS MOVING INTO THE CASCADES THIS MORNING.
SHOWERS WILL CONTINUE THROUGH THURSDAY. THE AIR MASS IS
UNSTABLE...SO THERE WILL BE A CHANCE OF THUNDERSTORMS ON THE COAST
THROUGH TONIGHT AND THROUGHOUT THE AREA ON THURSDAY. ANOTHER LOW
PRESSURE SYSTEM DEVELOPING OFF THE OREGON COAST WILL MOVE ACROSS THE
AREA OVER THE WEEKEND.

&&

.SHORT TERM...SATELLITE IMAGERY AND RADARS SHOW THE FRONT THAT
BROUGHT LOCALLY HEAVY RAIN AND WINDY CONDITIONS TO THE AREA DRAPED
FROM THE NORTHERN CASCADES INTO NORTHWEST OREGON THIS MORNING. THE
FRONT IS MOVING OFF TO THE SE. WIND ALONG THE COAST AND THROUGH THE
NORTHWEST INTERIOR DROPPED OFF RAPIDLY BEHIND THE FRONT...SO ALL OF
THE WIND ADVISORIES AND WARNINGS HAVE BEEN DROPPED. THE NATURE OF
THE PRECIPITATION HAS BECOME SHOWERY BEHIND THE FRONT...AND RADAR
AND LIGHTNING DATA SHOW THUNDERSTORMS OVER THE COASTAL WATERS. AS A
RESULT...A CHANCE OF THUNDERSTORMS WAS ADDED TO THE COAST AND
COASTAL WATERS FOR TODAY.

THE 12Z NAM12 AND GFS SOLUTIONS SHOW THE COOL AND UNSTABLE AIR MASS
OFFSHORE GRADUALLY MOVING INLAND TONIGHT INTO THURSDAY. GFS BUFR
SOUNDINGS SHOW CAPE VALUES RISING TO ABOUT 500 J/KG OVER THE
INTERIOR ON THU AND GFS MOS SHOWS THE CONDITIONAL PROBABILITY OF
TSTMS RISING TO OVER 30 PERCENT ACROSS THE AREA ON THU. SO A CHANCE
OF TSTMS WAS ADDED TO THE OLYMPIC PENINSULA FOR TONIGHT AND THE
ENTIRE AREA ON THU AS DISTURBANCES IN THE COOL AIR ROTATE INTO THE
AREA FROM THE SW.

SHOWERS DIMINISH THU NIGHT AND COME TO AN END FRI MORNING AS A DEEP
LOW DEVELOPS OFF THE NORTHERN CALIFORNIA OFFSHORE WATERS. THIS LOW
APPEARS TO BE DEVELOPING IN RESPONSE TO A SYSTEM DROPPING SE FROM
THE BERING SEA INTERACTS WITH THE REMAINS OF ANA NW OF HAWAII. THE
LATEST NAM12 AND GFS SOLUTIONS SHOW THE LOW REACHING ITS MAXIMUM
DEPTH AT AROUND 985-987 MB OFF THE CENTRAL OREGON COAST...WITH A
VERTICALLY STACKED MATURE LOW IN ITS DECAYING STAGE AS IT MOVES NE
ACROSS WESTERN WASHINGTON SAT NIGHT. OFFSHORE FLOW AND SHORT WAVE
RIDGING IN ADVANCE OF THIS LOW WILL LIKELY GIVE A DRY PERIOD FRI
AFTN THROUGH EARLY SAT WITH RAIN MOVING IN LATER SAT AND SAT NIGHT.
WHILE IT APPEARS THAT SUNDAY WILL BE WINDY...THE THREAT OF A WIND
STORM OVER WESTERN WASHINGTON APPEARS TO BE RELATIVELY LOW AT THIS
TIME DUE TO THE DECAYING NATURE OF THE STORM AND THE WIND FIELD
SPREADING OUT FROM ITS CENTER. ALBRECHT

.LONG TERM...FROM THE PREVIOUS LONG TERM DISCUSSION...THE AIR MASS
WILL REMAIN COOL AND UNSTABLE ON SUNDAY AS AN UPPER LEVEL TROUGH
MOVES INLAND. A RIDGE WILL THEN PASS OVERHEAD ON MON FOR A BREAK IN
THE WEATHER...WILL LIKELY SEE POPS DECREASED OVER THIS PERIOD. THEN
MORE RAIN AND BLUSTERY WEATHER BY TUE AS ANOTHER WET PAC FRONTAL
SYSTEM MOVES IN. 33

&&

.HYDROLOGY...A FLOOD WARNING REMAINS IN EFFECT FOR THE SKOKOMISH
RIVER IN MASON COUNTY. THE RIVER SHOULD CREST BY NOON TODAY THEN
SLOWLY FALL TO BELOW FLOOD STAGE TONIGHT.

HEAVY RAIN IN THE CASCADES IS NOT EXPECTED TO BE ENOUGH TO DRIVE ANY
OF THE CASCADE RIVERS ABOVE FLOOD STAGE. ALBRECHT

&&

.AVIATION...A CDFNT OVER THE INTERIOR WILL CONT MOVING SLOWLY E.
THIS FRONT WILL BE E OF THE CASCADES BY 0600 UTC THU. CONTD LOW
LEVEL SLY FLOW. THE AIR MASS WILL BECOME SLIGHTLY UNSTABLE OVER THE
COAST THIS AFTERNOON FOR A RISK OF ISOLD TSTMS. CONTD STRONG SW FLOW
ALOFT. THE MTNS WILL BE OBSCD.

MEANWHILE...EXPECT AREAS OF CIGS NEAR 1K FT ALONG WITH VSBYS IN THE
2-4SM RANGE DUE TO RAIN AND/OR FOG THIS MORNING. THERE SHOULD BE
SOME IMPROVEMENT THIS AFTERNOON...WITH AREAS OF CIGS IN THE 2-3K FT
RANGE ANTICIPATED. THERE WILL ALSO BE AREAS OF VSBYS IN THE 3-5SM
RANGE WITH THE HEAVIER PRECIP THIS AFTERNOON.

KSEA...EXPECT OCNL CIGS IN THE 2-3K FT RANGE TODAY. VSBYS WILL
LIKELY LOWER INTO THE 4-6SM RANGE WITH THE HEAVIER PRECIP. WINDS
WILL BE GENERALLY SLY AT 6-12 KNOTS.

&&

.MARINE...A SERIES OF SURFACE TROUGHS WILL MOVE ACROSS THE AREA
THROUGH THU. THE AIR MASS WILL ALSO BE UNSTABLE ENOUGH FOR A RISK OF
TSTMS. MEANWHILE...LOWER PRES OVER BRITISH COLUMBIA AND HIGH PRES
OVER CA WILL RESULT IN SOUTHERLY FLOW THROUGH THU. THE FLOW WILL
BECOME OFFSHORE OR EASTERLY ON FRI IN RESPONSE TO A DEEPENING
SURFACE LOW APPROACHING THE OREGON WATERS FROM THE SW.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WARNING IN EFFECT FOR THE SKOKOMISH RIVER IN MASON
      COUNTY.
     FLOOD WATCH MASON COUNTY.

PZ...SMALL CRAFT ADVISORIES ARE IN EFFECT FOR ALL WATERS EXCEPT
      THE CENTRAL STRAIT OF JUAN DE FUCA.
     SMALL CRAFT ADVISORY FOR ROUGH BAR IN EFFECT TIL 6 AM
      THURSDAY FOR THE GRAYS HARBOR BAR.

&&

$$

WWW.WEATHER.GOV/SEATTLE

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000
FXUS66 KSEW 221624
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
925 AM PDT WED OCT 22 2014

.SYNOPSIS...THE FRONTAL SYSTEM THAT PRODUCED LOCALLY HEAVY RAIN AND
WINDY CONDITIONS OVERNIGHT IS MOVING INTO THE CASCADES THIS MORNING.
SHOWERS WILL CONTINUE THROUGH THURSDAY. THE AIR MASS IS
UNSTABLE...SO THERE WILL BE A CHANCE OF THUNDERSTORMS ON THE COAST
THROUGH TONIGHT AND THROUGHOUT THE AREA ON THURSDAY. ANOTHER LOW
PRESSURE SYSTEM DEVELOPING OFF THE OREGON COAST WILL MOVE ACROSS THE
AREA OVER THE WEEKEND.

&&

.SHORT TERM...SATELLITE IMAGERY AND RADARS SHOW THE FRONT THAT
BROUGHT LOCALLY HEAVY RAIN AND WINDY CONDITIONS TO THE AREA DRAPED
FROM THE NORTHERN CASCADES INTO NORTHWEST OREGON THIS MORNING. THE
FRONT IS MOVING OFF TO THE SE. WIND ALONG THE COAST AND THROUGH THE
NORTHWEST INTERIOR DROPPED OFF RAPIDLY BEHIND THE FRONT...SO ALL OF
THE WIND ADVISORIES AND WARNINGS HAVE BEEN DROPPED. THE NATURE OF
THE PRECIPITATION HAS BECOME SHOWERY BEHIND THE FRONT...AND RADAR
AND LIGHTNING DATA SHOW THUNDERSTORMS OVER THE COASTAL WATERS. AS A
RESULT...A CHANCE OF THUNDERSTORMS WAS ADDED TO THE COAST AND
COASTAL WATERS FOR TODAY.

THE 12Z NAM12 AND GFS SOLUTIONS SHOW THE COOL AND UNSTABLE AIR MASS
OFFSHORE GRADUALLY MOVING INLAND TONIGHT INTO THURSDAY. GFS BUFR
SOUNDINGS SHOW CAPE VALUES RISING TO ABOUT 500 J/KG OVER THE
INTERIOR ON THU AND GFS MOS SHOWS THE CONDITIONAL PROBABILITY OF
TSTMS RISING TO OVER 30 PERCENT ACROSS THE AREA ON THU. SO A CHANCE
OF TSTMS WAS ADDED TO THE OLYMPIC PENINSULA FOR TONIGHT AND THE
ENTIRE AREA ON THU AS DISTURBANCES IN THE COOL AIR ROTATE INTO THE
AREA FROM THE SW.

SHOWERS DIMINISH THU NIGHT AND COME TO AN END FRI MORNING AS A DEEP
LOW DEVELOPS OFF THE NORTHERN CALIFORNIA OFFSHORE WATERS. THIS LOW
APPEARS TO BE DEVELOPING IN RESPONSE TO A SYSTEM DROPPING SE FROM
THE BERING SEA INTERACTS WITH THE REMAINS OF ANA NW OF HAWAII. THE
LATEST NAM12 AND GFS SOLUTIONS SHOW THE LOW REACHING ITS MAXIMUM
DEPTH AT AROUND 985-987 MB OFF THE CENTRAL OREGON COAST...WITH A
VERTICALLY STACKED MATURE LOW IN ITS DECAYING STAGE AS IT MOVES NE
ACROSS WESTERN WASHINGTON SAT NIGHT. OFFSHORE FLOW AND SHORT WAVE
RIDGING IN ADVANCE OF THIS LOW WILL LIKELY GIVE A DRY PERIOD FRI
AFTN THROUGH EARLY SAT WITH RAIN MOVING IN LATER SAT AND SAT NIGHT.
WHILE IT APPEARS THAT SUNDAY WILL BE WINDY...THE THREAT OF A WIND
STORM OVER WESTERN WASHINGTON APPEARS TO BE RELATIVELY LOW AT THIS
TIME DUE TO THE DECAYING NATURE OF THE STORM AND THE WIND FIELD
SPREADING OUT FROM ITS CENTER. ALBRECHT

.LONG TERM...FROM THE PREVIOUS LONG TERM DISCUSSION...THE AIR MASS
WILL REMAIN COOL AND UNSTABLE ON SUNDAY AS AN UPPER LEVEL TROUGH
MOVES INLAND. A RIDGE WILL THEN PASS OVERHEAD ON MON FOR A BREAK IN
THE WEATHER...WILL LIKELY SEE POPS DECREASED OVER THIS PERIOD. THEN
MORE RAIN AND BLUSTERY WEATHER BY TUE AS ANOTHER WET PAC FRONTAL
SYSTEM MOVES IN. 33

&&

.HYDROLOGY...A FLOOD WARNING REMAINS IN EFFECT FOR THE SKOKOMISH
RIVER IN MASON COUNTY. THE RIVER SHOULD CREST BY NOON TODAY THEN
SLOWLY FALL TO BELOW FLOOD STAGE TONIGHT.

HEAVY RAIN IN THE CASCADES IS NOT EXPECTED TO BE ENOUGH TO DRIVE ANY
OF THE CASCADE RIVERS ABOVE FLOOD STAGE. ALBRECHT

&&

.AVIATION...A CDFNT OVER THE INTERIOR WILL CONT MOVING SLOWLY E.
THIS FRONT WILL BE E OF THE CASCADES BY 0600 UTC THU. CONTD LOW
LEVEL SLY FLOW. THE AIR MASS WILL BECOME SLIGHTLY UNSTABLE OVER THE
COAST THIS AFTERNOON FOR A RISK OF ISOLD TSTMS. CONTD STRONG SW FLOW
ALOFT. THE MTNS WILL BE OBSCD.

MEANWHILE...EXPECT AREAS OF CIGS NEAR 1K FT ALONG WITH VSBYS IN THE
2-4SM RANGE DUE TO RAIN AND/OR FOG THIS MORNING. THERE SHOULD BE
SOME IMPROVEMENT THIS AFTERNOON...WITH AREAS OF CIGS IN THE 2-3K FT
RANGE ANTICIPATED. THERE WILL ALSO BE AREAS OF VSBYS IN THE 3-5SM
RANGE WITH THE HEAVIER PRECIP THIS AFTERNOON.

KSEA...EXPECT OCNL CIGS IN THE 2-3K FT RANGE TODAY. VSBYS WILL
LIKELY LOWER INTO THE 4-6SM RANGE WITH THE HEAVIER PRECIP. WINDS
WILL BE GENERALLY SLY AT 6-12 KNOTS.

&&

.MARINE...A SERIES OF SURFACE TROUGHS WILL MOVE ACROSS THE AREA
THROUGH THU. THE AIR MASS WILL ALSO BE UNSTABLE ENOUGH FOR A RISK OF
TSTMS. MEANWHILE...LOWER PRES OVER BRITISH COLUMBIA AND HIGH PRES
OVER CA WILL RESULT IN SOUTHERLY FLOW THROUGH THU. THE FLOW WILL
BECOME OFFSHORE OR EASTERLY ON FRI IN RESPONSE TO A DEEPENING
SURFACE LOW APPROACHING THE OREGON WATERS FROM THE SW.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WARNING IN EFFECT FOR THE SKOKOMISH RIVER IN MASON
      COUNTY.
     FLOOD WATCH MASON COUNTY.

PZ...SMALL CRAFT ADVISORIES ARE IN EFFECT FOR ALL WATERS EXCEPT
      THE CENTRAL STRAIT OF JUAN DE FUCA.
     SMALL CRAFT ADVISORY FOR ROUGH BAR IN EFFECT TIL 6 AM
      THURSDAY FOR THE GRAYS HARBOR BAR.

&&

$$

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000
FXUS66 KSEW 221041
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
340 AM PDT WED OCT 22 2014

.SYNOPSIS...A STRONG FRONTAL SYSTEM WILL MOVE THROUGH WESTERN
WASHINGTON TODAY. HEAVY RAIN WILL FALL IN THE OLYMPICS AND NORTH
CASCADES. THE RAIN WILL TURN TO SHOWERS TONIGHT AND THURSDAY.
ANOTHER LOW PRESSURE SYSTEM WILL REACH THE AREA LATE IN THE WEEK.

&&

.SHORT TERM...A HIGH WIND WARNING IS IN EFFECT FOR THE SAN JUANS AND
WESTERN WHATCOM THIS MORNING FOR SOUTH WINDS GUSTING TO 60 MPH. THIS
HIGH WIND IS CAUSED BY A TIGHT SURFACE LOW PASSING INTO SOUTHERN
BRITISH COLUMBIA. SOUTH WINDS WILL EASE BY MID MORNING.

THE FIRST WAVE OF HEAVY RAIN CONTINUES TO PASS THROUGH WESTERN WA
THIS MORNING. THREE INCHES FELL OVER THE NORTH COAST WITH 2-4 IN THE
OLYMPICS. THIS BAND WILL SHIFT EAST INTO THE INTERIOR AND CASCADES
THIS MORNING...WITH HEAVY RAIN ENDING OVER THE OLYMPICS. IT LOOKS
LIKE THE SECOND WAVE OF HEAVY RAIN WILL SHIFT SOUTH...CLIPPING THE
CENTRAL AND SOUTH CASCADES TONIGHT. IT LOOKS LIKE 1-3 INCHES ARE
EXPECTED IN THE CASCADES...BUT OVERALL RAIN AMOUNTS ARE LESS IN THE
CASCADES COMPARED TO PREVIOUS MODEL SOLUTIONS. THIS FRONT HAS BEEN
PRETTY PROGRESSIVE AND THIS LESSENS THE THREAT FOR RIVER FLOODING.
AS FOR THE INTERIOR...EXPECT RAIN AT TIMES THROUGH TONIGHT WITH 1-2
INCHES OF RAIN. TEMPS NEAR 60 DEGREES THIS AFTERNOON.

MOIST SOUTHWEST FLOW WILL CONTINUE THURSDAY AND THURSDAY NIGHT FOR
MORE SHOWERS ACROSS THE REGION. BUT HEAVY RAINS ARE NOT EXPECTED.
POPS WERE RAISED AS WE SHOULD SEE OFF-AND-ON SHOWERS THROUGHOUT MUCH
OF THE DAY.

WE MAY SEE A BRIEF BREAK IN THE WEATHER FRI MORNING...THEN MORE RAIN
WILL SPREAD NORTH INTO WESTERN WA FRI AFTERNOON AND EVENING.

EXPECT MORE WET AND WINDY WEATHER ON SATURDAY. THE MAIN IMPACT WILL
BE THE WIND AND THE TRACKING OF A SURFACE LOW OFF THE WA COAST.
MODELS BRING A 980S MB LOW INTO WESTERN WA SAT AFTERNOON WITH HIGH
WIND POSSIBLE...ESPECIALLY ALONG THE COAST. STRONG WINDS MAY ALSO
OCCUR IN THE INTERIOR AS THIS SYSTEM MOVES INLAND SAT NIGHT. WILL
NEED TO WATCH THIS SYSTEM MORE CLOSELY AS IT EVOLVES. 33

.LONG TERM...THE AIR MASS WILL REMAIN COOL AND UNSTABLE ON SUNDAY AS
AN UPPER LEVEL TROUGH MOVES INLAND. A RIDGE WILL THEN PASS OVERHEAD
ON MON FOR A BREAK IN THE WEATHER...WILL LIKELY SEE POPS DECREASED
OVER THIS PERIOD. THEN MORE RAIN AND BLUSTERY WEATHER BY TUE AS
ANOTHER WET PAC FRONTAL SYSTEM MOVES IN. 33

&&

.HYDROLOGY...A FLOOD WARNING IS IN EFFECT FOR THE SKOKOMISH RIVER IN
MASON COUNTY. THE RIVER IS RISING AND IS EXPECTED TO REACH MINOR
FLOOD STAGE THIS MORNING.

HEAVY RAIN WILL FALL IN THE CASCADES THIS MORNING AND AFTERNOON WITH
1-3 INCHES EXPECTED. BUT OVERALL PRECIP AMOUNTS ARE LESS COMPARED TO
PREVIOUS SOLUTIONS. EXPECT SHARP RISES ON THE RIVERS...BUT IT
APPEARS FLOODING IS UNLIKELY.

&&

.AVIATION...A 995 MB SURFACE LOW TRACKING NE OVER CENTRAL VANCOUVER
ISLAND WILL DRAG A FRONT THROUGH WRN WA THIS MORNING. THIS SYSTEM
WILL BRING STRONG FLOW ALOFT TO WRN WA...BECOMING LIGHT TO MODERATE
SW FLOW TONIGHT. MOIST AND GENERALLY STABLE. RAIN AT TIMES. CIGS
MOSTLY VFR BUT OCCASIONALLY MVFR WITH HEAVIER PRECIPITATION.

KSEA...SLY WINDS 12-15 W/ GUSTS 25-30 KT...EASING LATER THIS
MORNING. RAIN AT TIMES. CIGS MOSTLY VFR ABOVE 3K FT. VIS 4-5 SM AT
TIMES DURING HEAVIER PRECIPITATION.

&&

.MARINE...STRONG SE PRESSURE GRADIENTS WILL PRODUCE HIGH END GALE
FORCE WINDS OVER THE COASTAL WATERS...ENTRANCES TO THE STRAIT...AND
INLAND WATERS N OF PUGET SOUND EARLY THIS MORNING. SMALL CRAFT WINDS
TO 30 KT ARE EXPECTED IN PUGET SOUND/CENTRAL STRAIT...CONTINUING
INTO THE AFTERNOON IN PUGET SOUND. WINDS WILL EASE FIRST ALONG THE
COAST AFTER 5-6 AM...THEN ACROSS THE INTERIOR AFTER 8-9 AM. SEAS
OVER 15 FEET ARE ALSO EXPECTED TODAY ALONG WITH ROUGH BAR
CONDITIONS.

THERE WILL BE A RELATIVE LULL IN THE STORMY WEATHER IN THE MIDDLE OF
THE WEEK...THEN ANOTHER STRONG WEATHER SYSTEM WILL AFFECT THE WATERS
FRIDAY AND SATURDAY. A DEEP SURFACE LOW IS EXPECTED TO TRACK THROUGH
THE WATERS DURING THIS TIME BUT THERE IS STILL A LOT OF UNCERTAINTY
WITH HOW STRONG THE LOW WILL BE AND WHERE IT WILL GO. DTM

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...HIGH WIND WARNING SAN JUANS AND WESTERN WHATCOM UNTIL 9 AM THIS
     MORNING.
     WIND ADVISORY COAST UNTIL 8 AM THIS MORNING.
     WIND ADVISORY WESTERN SKAGIT AND ADMIRALTY INLET UNTIL 9 AM
     THIS MORNING.
     FLOOD WATCH MASON COUNTY.

PZ...GALE WARNING COASTAL WATERS...ENTRANCES TO THE STRAIT OF JUAN
     DE FUCA...NORTHERN INLAND WATERS...AND ADMIRALTY INLET.
    .SMALL CRAFT ADVISORY CENTRAL STRAIT OF JUAN DE FUCA AND PUGET
     SOUND AND HOOD CANAL.
    .SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.

&&

$$

WWW.WEATHER.GOV/SEATTLE

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