Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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000
FXUS66 KSEW 101140
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
340 AM PST WED FEB 10 2016

.SYNOPSIS...MOIST SOUTHWEST FLOW ALOFT WILL ALLOW WETTER WEATHER TO
RETURN TO WESTERN WASHINGTON THROUGH THE WEEKEND. A WEAK FRONT
WILL BRING AT LEAST A CHANCE OF RAIN TO THE AREA THROUGH TONIGHT. RAIN
WILL INCREASE AS A WARM FRONT REACHES THE AREA THURSDAY...FOLLOWED
BY A COLD FRONT THURSDAY NIGHT AND FRIDAY. AN UPPER LEVEL TROUGH
WILL PRODUCE SHOWERS FRIDAY NIGHT INTO SATURDAY. ANOTHER WARM
FRONT WILL BRING RAIN THE REST OF THE WEEKEND.

&&

.SHORT TERM...SATELLITE IMAGERY SHOWS UPPER LEVEL RIDGE THAT
BROUGHT THE RECORD SETTING HIGH TEMPERATURES TO THE AREA IS NOW
WELL TO THE EAST. MID AND HIGH LEVEL CLOUDS OVER WESTERN
WASHINGTON EARLY THIS MORNING. TEMPERATURES AT 3 AM WERE IN THE
UPPER 30S TO LOWER 50S.

CLOUDS CONTINUING TO INCREASE THIS MORNING AS A WEAK SYSTEM
APPROACHES THE AREA. STILL SOME HOLES IN THE OVERCAST EARLY THIS
MORNING AND WITH TEMPERATURE/DEW POINT SPREADS NEAR ZERO PATCHY
FOG IS STILL A POSSIBILITY. A COLORFUL SUNRISE IS ALSO STILL
POSSIBLE. DOPPLER RADAR PICKING UP SOME ECHOES EARLY THIS MORNING
BUT SURFACE OBSERVATIONS REPORTING CEILINGS AT OR ABOVE 12000 FEET
SO MOST IF NOT ALL OF THE PRECIPITATION IS NOT REACHING THE
GROUND. BETTER CHANCES FOR RAIN LATER THIS MORNING INTO THE
AFTERNOON HOURS AS THE SYSTEM GETS NEAR THE COAST. THE FRONT IS
NEGATIVELY TILTED AND WEAKENING SO WILL CONTINUE WITH THE IDEA OF
LIKELY POPS ON THE COAST AND CHANCE POPS INLAND TODAY. WITH ALL
THE CLOUD COVER AND A MUCH COOLER AIR MASS ALOFT HIGH TEMPERATURES
TODAY WILL BE MUCH COOLER THAN TUESDAY...IN THE LOWER TO MID 50S.

WHAT IS LEFT OF THE SYSTEM MOVING THROUGH THE AREA THIS EVENING
KEEPING AT LEAST CHANCE POPS IN THE FORECAST. A BIT OF A BREAK
LATER TONIGHT INTO THURSDAY MORNING. RAIN OUT AHEAD OF THE NEXT
SYSTEM...CURRENTLY DEVELOPING IN THE BOTTOM OF A DEEP UPPER LEVEL
TROUGH THAT EXTENDS FROM THE GULF OF ALASKA DOWN TO NEAR
30N/150W...WILL REACH THE AREA THURSDAY AFTERNOON. LOWS TONIGHT
WILL BE MOSTLY IN THE 40S WITH HIGHS IN THE MID 50S ON THURSDAY.

WARM FRONT MOVING THROUGH WESTERN WASHINGTON THURSDAY NIGHT WITH
THE TRAILING COLD FRONT ARRIVING FRIDAY MORNING. 00Z AND NEW 06Z
MODEL SOLUTIONS ARE CONSISTENT ON THE TIMING OF THE FRONT...
PUTTING IT EAST OF THE AREA IN THE AFTERNOON...SO WILL GO WITH
SHOWER WORDING FOR FRIDAY AFTERNOON. HIGHS ON FRIDAY IN THE 50S.

.LONG TERM...THERE IS GOOD AGREEMENT ON THE GENERAL PATTERN IN THE
EXTENDED MODELS THIS MORNING WITH AN UPPER LEVEL TROUGH MOVING
THROUGH WESTERN WASHINGTON SATURDAY MORNING. LONG FETCH OF
MOISTURE AIMED AT THE PACIFIC NORTHWEST BEGINNING SATURDAY NIGHT
AND CONTINUING THROUGH MONDAY WITH AN UPPER LEVEL RIDGE BUILDING
TO THE SOUTH. THE MODELS HAVE BEEN BOUNCING AROUND ON JUST HOW
STRONG THE RIDGE WILL BE AND IF THE RIDGE WILL BE STRONG ENOUGH TO
PUSH THE MOISTURE NORTH OF WESTERN WASHINGTON. THE 00Z RUNS KEEP
THE AREA WET THROUGH SUNDAY THEN TRY TO LIFT THE BAND NORTH ON
MONDAY. CURRENT FORECAST FOLLOWS THIS TREND SO WILL STAY WIT WITH
THE LIKELY POPS SATURDAY NIGHT THROUGH SUNDAY NIGHT AND CHANCE
POPS FOR MONDAY AND TUESDAY IN THE MORNING FORECAST PACKAGE.

&&

.AVIATION...SW FLOW ALOFT WITH INCREASING MOISTURE FROM A SERIES OF
WEAK FRONTS. THERE WILL BE RAIN AT TIMES ON THE COAST BUT
LOW LEVEL OFFSHORE FLOW SHOULD DRY UP MOST OF THE RAIN FOR THE
INTERIOR OF WESTERN WA TODAY WITH JUST SOME SPRINKLES.

KSEA...CLOUDS WILL INCREASE AND THERE IS A CHANCE OF RAIN THIS
AFTERNOON WITH A WEAK FRONT.

&&

.MARINE...A WEAK FRONT WILL BRING SMALL CRAFT ADVISORY SOUTHEAST
WIND TO THE COASTAL WATERS THIS AFTERNOON AND EVENING.  ANOTHER
FRONTAL SYSTEM WILL STALL JUST OFFSHORE THU AND FRI...MOVING INLAND
SAT.


&&

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

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY FROM NOON TODAY TO 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.

&&

$$

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