High Wind in Washington, December 10, 2014

AREA FORECAST DISCUSSION...CORRECTED TYPO IN SYNOPSIS
NATIONAL WEATHER SERVICE SEATTLE WA
300 AM PST WED DEC 10 2014

.SYNOPSIS...A VIGOROUS FRONTAL SYSTEM WILL MOVE THROUGH WESTERN
WASHINGTON TODAY...BRINGING LOCALLY HIGH WINDS TO THE COAST AND
NORTHWEST INTERIOR AND HEAVY RAIN TO THE MOUNTAINS ESPECIALLY. THEN
A DEEP LOW PRESSURE SYSTEM COULD BRING MORE WIDESPREAD HIGH WINDS AS
IT MOVES THROUGH THURSDAY AND THURSDAY NIGHT. COOLER SHOWERY WEATHER
WILL FOLLOW ON FRIDAY...WITH DRY WEATHER EXPECTED THIS WEEKEND.

&&

.SHORT TERM...THE NEXT VIGOROUS FRONTAL SYSTEM IS MAKING ITS WAY
INTO THE PACIFIC NORTHWEST EARLY THIS MORNING. ITS WARM FRONT MOVED
INTO WESTERN WASHINGTON FROM THE SOUTHWEST OVERNIGHT...WITH RAIN
INCREASING AGAIN ESPECIALLY IN SOUTHWEST WASHINGTON...AT THE
COAST...AND OVER THE OLYMPIC PENINSULA. THE COLD FRONT IS OVER THE
OUTER OFFSHORE WATERS AND EXTENDS SOUTHWEST...WHILE THE PARENT LOW
IS OUT NEAR 50N/134W. THE SNOW LEVEL IS AROUND 6000 TO 7000 FT...
WITH 2 AM TEMPERATURES IN THE UPPER 40S TO MID 50S.

THE WARM FRONT WILL CONTINUING NORTHWARD ACROSS THE FORECAST AREA
TODAY AND MOVE INTO SOUTHWEST BRITISH COLUMBIA LATE THIS AFTERNOON.
AT THE SAME TIME THE COLD FRONT WILL MOVE INTO WESTERN WASHINGTON
FROM THE COASTAL WATERS THIS AFTERNOON...AND THE SURFACE LOW WILL
TRACK NORTHWARD TO THE WEST SIDE OF HAIDA GWAII.

THIS SYSTEM WILL PROBABLY PRODUCE SOME HIGH WINDS AT TIMES ALONG THE
COAST AND IN THE NORTHWEST INTERIOR...BEGINNING EARLY THIS MORNING
THROUGH THE COLD FRONT PASSAGE THIS AFTERNOON. A HIGH WIND WARNING
REMAINS IN EFFECT FOR THOSE ZONES THROUGH THIS AFTERNOON...FOR
SUSTAINED WINDS AS HIGH AS 45 MPH AND GUSTS AS HIGH AS 60 TO 70 MPH.
IT WILL BE BREEZY TO MERELY WINDY ACROSS THE PUGET SOUND REGION AND
SOUTHWEST INTERIOR.

SIGNIFICANT PRECIPITATION WILL CONTINUE TODAY AS WELL. THE HEAVIEST
RAINFALL WILL ONCE AGAIN BE OVER THE OLYMPICS AND THE NORTH CASCADES
AROUND MOUNT BAKER...WITH 2 TO AS MUCH AS 6 INCHES. FURTHER SOUTH IN
THE CASCADES...RAINFALL WILL MOSTLY BE IN THE 1 TO 3.5 INCH RANGE...
WITH 0.5 TO 2 INCHES OF RAIN ACROSS THE WESTERN WASHINGTON LOWLANDS.

ANOTHER STRONG FRONTAL SYSTEM WILL AFFECT WESTERN WASHINGTON
THURSDAY AND THURSDAY NIGHT. THIS FEATURE WILL BE A LESS SERIOUS
RAIN PRODUCER...BUT IT HAS THE POTENTIAL TO BRING MORE WIDESPREAD
HIGH WINDS TO THE FORECAST AREA. MANY MODEL RUNS SHOW A 982 MB
SURFACE LOW TRACKING NORTH-NORTHEAST FROM THE OREGON COASTAL WATERS
ACROSS THE WESTERN WASHINGTON INTERIOR. HOWEVER OTHER RUNS --
INCLUDING THE MOST RECENT GFS -- KEEP THE SURFACE LOW TO WEST OF
PUGET SOUND OR EVEN OVER THE COASTAL WATERS. THAT TRACK WOULD NOT
RESULT IN HIGH WINDS FOR MUCH OF THE WESTERN WASHINGTON INTERIOR.
BOTTOM LINE IS THAT THE HIGH WIND WATCH ISSUED ON TUESDAY WILL
REMAIN IN EFFECT...BUT CONFIDENCE IS NOT ALL THAT GREAT.

AN UPPER TROUGH WILL MOVE INTO WESTERN WASHINGTON FROM THE WEST ON
FRIDAY...BRINGING SCATTERED SHOWERS WITH THE SNOW LEVEL AROUND
3500 FT.   MCDONNAL

.LONG TERM...THE UPPER TROUGH WILL MOVE EAST OF THE CASCADES FRIDAY
NIGHT...AND A WEAK UPPER RIDGE WILL PROGRESS ACROSS WESTERN
WASHINGTON SATURDAY AND SATURDAY NIGHT. THEN A WEAK SPLITTING FRONT
WILL SLOWLY APPROACH THE PACIFIC NORTHWEST. SATURDAY AND SUNDAY
SHOULD BE DRY DAYS FOR WESTERN WASHINGTON. THE SPLITTING FRONT COULD
BRING SOME RELATIVELY LIGHT RAIN TO THE AREA EARLY NEXT WEEK.
MCDONNAL

&&

.HYDROLOGY...A BREAK IN THE PRECIPITATION TUESDAY EVENING ALLOWED
SOME OF THE RIVERS TO RECEDE. RAINFALL RATES HAVE PICKED UP AFTER
MIDNIGHT WITH ANOTHER ROUND OF HEAVY RAIN FORECAST FOR THE OLYMPICS
AND NORTH CASCADES TODAY. AN ADDITIONAL 3 TO 6 INCHES OF RAIN IS
EXPECTED IN THE OLYMPICS WITH 2 TO 4 INCHES IN THE NORTH CASCADES BY
LATE TONIGHT. THE CENTRAL CASCADES WILL SEE LESSER AMOUNTS...1 TO
2.5 INCHES. SNOW LEVELS WILL REMAIN HIGH TODAY...6000 TO 7000
FEET...LOWERING TO NEAR 4500 FEET TONIGHT. THE HEAVY RAIN AND HIGH
SNOW LEVELS WILL KEEP THE THREAT OF FLOODING ON RIVERS DRAINING OFF
THE OLYMPICS AND NORTH CASCADES THROUGH AT LEAST TODAY.

EVEN WITH A BREAK IN THE RAIN THE SKOKOMISH RIVER REMAINED ABOVE
FLOOD STAGE OVERNIGHT. THE ADDITIONAL RAIN TODAY WILL DRIVE THE
SKOKOMISH RIVER ABOVE MAJOR FLOOD STAGE.

OTHER RIVERS OF CONCERN TODAY INCLUDE BUT ARE NOT LIMITED TO...THE
BOGACHIEL...ELWHA...DUNGENESS...NOOKSACK AND SKAGIT. ALL OF THESE
RIVERS ARE FORECASTED TO RISE TO NEAR OR ABOVE FLOOD STAGE LATER
TODAY INTO TONIGHT. A FLOOD WATCH WILL REMAIN IN EFFECT FOR MUCH OF
THE CWA THROUGH FRI AFTERNOON.

IN ADDITION TO FLOOD CONCERNS...RECENT AND IMMINENT HEAVY RAINS
WILL INCREASE THE RISK OF LANDSLIDES ACROSS THE CWA...ESPECIALLY
IN AREAS WHERE THERE ARE STEEP COASTAL BLUFFS OR STEEP HILLSIDES.
THE THREAT OF LANDSLIDES WILL LIKELY PERSIST THROUGH AT LEAST THU OR
FRI. FELTON

&&

.AVIATION...A WET WINDY FRONTAL SYSTEM WILL MOVE THROUGH WESTERN WA
THIS MORNING. THE AIR MASS IS MOIST AND STABLE...ALTHOUGH WITH
STRONG WINDS ALOFT THERE WILL BE TURBULENCE AND WIND SHEAR. AFTER
RAIN THIS MORNING...WE MAY SEE SOME SUNBREAKS AGAIN FOLLOWING THE
FRONTAL PASSAGE LATER THIS AFTERNOON AND EVENING.

KSEA...THE FRONTAL SYSTEM MOVING THROUGH WRN WA THIS MORNING
HAS STRONG WINDS ALOFT SO THERE IS A WS020/18055KT IN THE TAF TIL
FROPA EARLY THIS AFTERNOON.

&&

.MARINE...A STRONG FRONTAL SYSTEM WILL MOVE THROUGH WRN WA THIS
MORNING THROUGH EARLY THIS AFTERNOON. STORM WARNINGS ARE IN EFFECT
FOR THE WINDIER SPOTS WITH GALE WARNINGS ELSEWHERE. THERE IS A
CHANCE THAT A DEEP LOW WILL MOVE THROUGH WRN WA THU AFTERNOON OR
EVENING...THAT SYSTEM HAS NOT YET BEGUN TO DEVELOP BUT IT WILL SPIN
UP FAST LATER TODAY AND TONIGHT...AND THERE IS A STORM WATCH UP FOR
THAT. WITH A DECENT TIDAL ANOMALY THERE IS A TIDAL OVERFLOW
STATEMENT IN EFFECT FOR THE MORNING HIGH TIDE.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...FLOOD WARNINGS/WATCHES ARE IN EFFECT FOR PARTS OF THE CWA.

     HIGH WIND WARNING IN EFFECT TIL 4 PM TODAY FOR THE COAST
     AND NORTHWEST INTERIOR.

     HIGH SURF ADVISORY IN EFFECT TIL 9 PM TODAY FOR THE COAST.

     COASTAL FLOOD ADVISORY IN EFFECT TIL NOON TODAY FOR
     THE SHORELINES BORDERING THE PUGET SOUND/HOOD CANAL...
     ADMIRALTY INLET...AND NORTHERN INLAND WATERS.

     HIGH WIND WATCH IN EFFECT FOR THE ENTIRE CWA FROM LATE
     TONIGHT THROUGH THURSDAY EVENING.

PZ...STORM WARNING IN EFFECT TIL 4 PM WEDNESDAY FOR THE COASTAL
     WATERS...ENTRANCES TO THE STRAIT OF JUAN DE FUCA AND
     NORTHERN INLAND WATERS.

     GALE WARNING IN EFFECT FOR ADMIRALTY INLET...THE CENTRAL
     STRAIT...PUGET SOUND AND HOOD CANAL.

     SMALL CRAFT ADVISORY IN EFFECT FOR SEVERE BAR CONDITIONS.

     STORM WATCH IN EFFECT FOR THURSDAY AFTERNOON AND EVENING
     FOR ALL WATERS.

&&

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