Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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000
FXUS66 KSEW 102255
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
300 PM PST WED FEB 10 2016

.SYNOPSIS...IN THE WAKE OF A WEAK FRONT THERE WILL BE A CHANCE OF
RAIN THIS EVENING BUT ALSO PARTIAL CLEARING. RAIN WILL INCREASE
THURSDAY AFTERNOON AND EVENING AS A WARM FRONT REACHES THE AREA. A
COLD FRONT WILL FOLLOW THURSDAY NIGHT AND FRIDAY. AN UPPER LEVEL
TROUGH WILL PRODUCE SHOWERS FRIDAY NIGHT AND SATURDAY. ANOTHER FRONT
WILL BRING RAIN SATURDAY NIGHT AND SUNDAY.

&&

.SHORT TERM...A WEAK FRONT MOVED THROUGH THE REGION THIS MORNING. IT
DID HAVE ENOUGH PUNCH TO BRING A LITTLE RAIN TO MOST AREAS. ANOTHER
IMPULSE IS CURRENTLY ALONG THE COAST AND IT WILL KEEP A CHANCE OF
RAIN GOING TONIGHT. THERE WILL BE SOME CLEARING BEHIND THIS IMPULSE
AS IS EVIDENT ON SATELLITE IMAGERY.

THE NEXT SYSTEM WILL ARRIVE FROM THE SOUTHWEST. RECENT MODEL RUNS
HAVE SLOWED THIS SYSTEM A BIT...NOW IT APPEARS MOST OF THE RAIN WILL
REACH THE INTERIOR OF WESTERN WASHINGTON AFTER 00Z FRIDAY. IT WILL
RAIN THURSDAY NIGHT...THEN A COLD FRONT WILL MOVE THROUGH FRIDAY
MORNING...GIVING SHOWERS FRIDAY AFTERNOON. HIGHS WILL BE IN THE
MID 50S BOTH THURSDAY AND FRIDAY.

AN UPPER LEVEL TROUGH WILL MOVE THROUGH THE AREA FRIDAY NIGHT AND
SATURDAY. SHOWERS ARE LIKELY DURING THIS PERIOD. THE SNOW LEVEL...
WHICH WILL HAVE BEEN AT 6000 FEET OR HIGHER UNTIL NOW...WILL FALL TO
3000-4000 FEET. ON SATURDAY AFTERNOON THE NEXT SYSTEM WILL APPROACH
FROM THE WEST...WITH RAIN DEVELOPING ON THE COAST. SATURDAY HIGHS
WILL BE IN THE LOW 50S. BURKE

.LONG TERM...SATURDAY NIGHT THROUGH SUNDAY NIGHT LOOKS LIKE A RAINY
PERIOD. ON MONDAY MODELS SHIFT THE RAIN NORTH TO VARYING DEGREES.
MODEL SIMILARITY IS LACKING AFTER THAT AND HAVE KEPT BROAD BRUSH
CHANCE POPS IN THE FORECAST FOR TUESDAY AND WEDNESDAY. IT DOES
APPEAR WESTERN WASHINGTON WILL BE IN THE WARM SECTOR FOR MOST OF THE
EXTENDED PERIOD...GIVING TEMPERATURES A FEW TO SEVERAL DEGREES ABOVE
NORMAL. BURKE

&&

.HYDROLOGY...RIVER FLOODING IS UNLIKELY THROUGH SATURDAY. THERE IS
SOME POTENTIAL FOR HEAVY RAIN OVER THE OLYMPICS BEGINNING SATURDAY
NIGHT WHICH COULD CAUSE THE SKOKOMISH RIVER TO FLOOD EARLY NEXT WEEK.

&&

.AVIATION...SW FLOW ALOFT. THE AIR MASS IS STABLE AND SOMEWHAT
MOIST. A WEAK FRONTAL SYSTEM IS PUSHING EAST ACROSS THE AREA LATE
THIS AFTERNOON AND WILL DISSIPATE AS IT MOVES ACROSS THE CASCADES
THIS EVENING. A WARM FRONT WILL DEVELOP OFF THE CALIFORNIA COAST AND
MOVE NE THROUGH WESTERN WASHINGTON LATE THU AFTERNOON.

THE INCOMING FRONT SHEARED APART TODAY WITH UPPER LEVEL BOUNDARY
PORTIONS MOVING ACROSS THE AREA EARLIER TODAY AND THE SURFACE
BOUNDARY MOVING ONSHORE LATE THIS AFTERNOON AND THROUGH THE INTERIOR
EARLY THIS EVENING. CONDITIONS THIS AFTERNOON HAVE IMPROVED TO VFR
WITH LOCAL MVFR CEILINGS. A FEW SHOWERS WITH MVFR CIGS MAY ACCOMPANY
THE FRONT AS IT MOVES THROUGH LATE THIS AFTERNOON...BUT FLOW ALOFT
INTERACTING WITH THE COASTAL TERRAIN IS PROVIDING SOME OCCASIONAL
CLEARING IN THE INTERIOR VALLEYS AND CONFIDENCE IN THE CEILING
FORECAST IN THE SHORT TERM IS LOW. CONDITIONS WILL IMPROVE TO MVFR
WITH CIGS RISING TO ABOUT 060 AS LOW LEVEL FLOW BACKS TO MORE
EASTERLY LATE TONIGHT INTO THU MORNING.

CIGS WILL LOWER TO AROUND OVC030 LATE THU AFTERNOON AS PRECIPITATION
AHEAD OF AN INCOMING WARM FRONT INCREASES. ALBRECHT

KSEA...THE DISCUSSION ABOVE APPLIES. WINDS 13005-08KT WILL BACK TO
AROUND 09005KT ABOUT 06Z TONIGHT THEN BECOME 02005-07KT ABOUT 12Z AS
THE WARM FRONT APPROACHES FROM THE SW. ALBRECHT

&&

.MARINE...A FRONT ALONG THE COAST WILL MOVE THROUGH THE INLAND
WATERS EARLY THIS EVENING. SMALL CRAFT ADVISORY SOUTH WINDS OVER THE
COASTAL WATERS AND S TO SE WINDS OVER ADMIRALTY INLET AND NORTHERN
PORTIONS OF PUGET SOUND AHEAD OF AND WITH THIS FRONT WILL DIMINISH
AS THE FRONT MOVES OFF TO THE EAST OF THE WATERS AND DISSIPATES.

A STRONGER WARM FRONT WILL APPROACH THE WATERS FROM THE SW ON THU.
EXPECT SMALL CRAFT ADVISORY EAST TO SOUTHEAST WINDS TO DEVELOP OVER
THE COASTAL WATERS AND AT THE WEST ENTRANCE TO THE STRAIT THU
MORNING THE SPREADING INTO THE EAST ENTRANCE LATE THU AFTERNOON AND
THU NIGHT. A COLD FRONT WILL MOVE THROUGH THE WATERS LATE THU NIGHT
AND FRI MORNING.

MODERATE ONSHORE FLOW WILL FOLLOW FRI AFTERNOON OR EVENING INTO SAT
MORNING. SMALL CRAFT ADVISORY SOUTH TO SOUTHWEST WINDS CAN BE
EXPECTED IN THE PUGET SOUND AND HOOD CANAL AREA WHILE SMALL CRAFT
ADVISORY WESTERLY FLOW CAN BE EXPECTED OVER THE CENTRAL AND EASTERN
STRAIT OF JUAN DE FUCA FRI AFTERNOON.

A SLOW MOVING FRONT TO THE NW OF THE AREA WILL GIVE STRONG ONSHORE
FLOW TO THE REGION LATE SAT NIGHT OR SUN INTO MON OR TUE. ALBRECHT

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY UNTIL MIDNIGHT PST TONIGHT FOR COASTAL
     WATERS FROM CAPE FLATTERY TO JAMES ISLAND 10 TO 60 NM-
     COASTAL WATERS FROM CAPE FLATTERY TO JAMES ISLAND OUT 10 NM-
     COASTAL WATERS FROM JAMES ISLAND TO POINT GRENVILLE 10 TO
     60 NM-COASTAL WATERS FROM JAMES ISLAND TO POINT GRENVILLE
     OUT 10 NM-COASTAL WATERS FROM POINT GRENVILLE TO CAPE
     SHOALWATER 10 TO 60 NM-COASTAL WATERS FROM POINT GRENVILLE
     TO CAPE SHOALWATER OUT 10 NM.

     SMALL CRAFT ADVISORY UNTIL 9 PM PST THIS EVENING FOR ADMIRALTY
     INLET-PUGET SOUND AND HOOD CANAL.

&&

$$

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