Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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FXUS66 KSEW 092251
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
300 PM PST TUE FEB 9 2016

.SYNOPSIS...A WETTER PERIOD WILL BEGIN WEDNESDAY AS A WEAK FRONT
MOVES INTO THE REGION FROM THE WEST. A STRONGER SYSTEM WILL ARRIVE
FROM THE SOUTHWEST ON THURSDAY. RAIN AT TIMES WILL CONTINUE FRIDAY
WITH SHOWERS ON SATURDAY. ANOTHER SYSTEM WILL ARRIVE AROUND SUNDAY.

&&

.SHORT TERM...ONE LAST SUNNY DAY TODAY...WITH HEIGHTS IN THE 570S...
HAS GIVEN HIGH TEMPERATURES FROM THE MID 50S TO MID 60S OVER MOST
AREAS. KUIL ON THE COAST REACHED 73...WHICH TIES THE ALL TIME
FEBRUARY RECORD AT THIS SITE.

AN UPPER LEVEL RIDGE NOW CENTERED OVER EASTERN WASHINGTON WILL
WEAKEN TONIGHT. A WEAK SYSTEM EMBEDDED IN SOUTHWESTERLY FLOW ALOFT
WILL BRUSH THE COAST 12Z-15Z WEDNESDAY AND PERHAPS SPREAD SOME LIGHT
RAIN INLAND DURING THE DAY WEDNESDAY. MODELS GENERALLY HAVE LOW QPF
WITH THIS SYSTEM SO POPS ARE BOOSTED BUT ARE STILL MAINLY IN THE
CHANCE CATEGORY. WITH LOTS OF CLOUD COVER THE HIGHS ON WEDNESDAY
WILL BE MAINLY IN THE 50S.

SOME DRYING WILL OCCUR WEDNESDAY NIGHT. A STRONGER SYSTEM WILL
ARRIVE FROM THE SOUTHWEST ON THURSDAY. RAIN IS LIKELY ON THE COAST
IN THE MORNING AND WILL BECOME LIKELY INLAND IN THE AFTERNOON. THE
PATTERN LOOKS MORE FRONTAL STARTING THURSDAY NIGHT AND THIS FRONT
SLOWLY MOVES THROUGH THE AREA FRIDAY FOR RAIN AT TIMES. HIGHS ON
THURSDAY AND FRIDAY WILL BE IN THE 50S. THE SNOW LEVEL WILL BE
6000 FEET OR HIGHER THROUGH FRIDAY. BURKE

.LONG TERM...AN UPPER TROUGH MOVES THROUGH THE AREA ON SATURDAY SO
THIS DAY WILL BE SHOWERY. ANOTHER SYSTEM ARRIVES FROM THE WEST ON
SUNDAY WITH RAIN LIKELY THROUGH MONDAY MORNING. MODELS DIVERGE AFTER
THAT WITH THE GFS SENDING SUBSEQUENT SYSTEMS NORTH AND THE EURO
STILL AIMING THEM AT WESTERN WASHINGTON. HAVE KEPT POPS MAINLY IN
THE CHANCE CATEGORY MONDAY AND TUESDAY. THE SNOW LEVEL WILL FALL TO
AROUND 3000 FEET OVER THE WEEKEND THEN RISE TO 7000 FEET OR SO EARLY
NEXT WEEK. BURKE

&&

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

&&

.AVIATION...AN UPPER RIDGE WILL REMAIN OVER EASTERN WASHINGTON
THROUGH WEDNESDAY. SW FLOW ALOFT. HIGH PRESSURE EAST OF THE CASCADES
WITH LOWER PRESSURE OFFSHORE WILL GIVE OFFSHORE FLOW THROUGH
TONIGHT. FLOW WILL BECOME MORE SLY ON WED. THE AIR MASS IS DRY AND
STABLE. MID AND HIGH LEVEL MOISTURE WILL INCREASE LATE TONIGHT AND
WED AS A WARM FRONT OFFSHORE MOVES NE THROUGH THE COASTAL WATERS.

EXPECT GOOD VFR CONDITIONS TONIGHT. THE EXCEPTION WILL BE FOG-PRONE
VALLEYS OF MAINLY THE SOUTH INTERIOR WHERE SHALLOW FOG WILL DEVELOP
LATE TONIGHT INTO WED MORNING. ALBRECHT

KSEA...P6SM BKN250. THICKENING MID AND HIGH LEVEL CLOUDS LATE
TONIGHT AND WED MORNING WILL LIKELY KEEP FOG FROM FORMING AROUND THE
TERMINAL WED MORNING. VARIABLE WINDS 3-5 KNOTS WILL BECOME SELY
4-8 KT LATE TONIGHT INTO WED. ALBRECHT

&&

.MARINE...HIGH PRESSURE EAST OF THE CASCADES AND LOWER PRESSURE
OFFSHORE IS GIVING OFFSHORE FLOW. OFFSHORE FLOW WILL CONTINUE
THROUGH TONIGHT. SMALL CRAFT ADVISORY SOUTHEAST WINDS ARE NOW
EXPECTED THROUGH THIS EVENING FOR ALL COASTAL ZONES EXCEPT THE INNER
COASTAL ZONE FROM POINT GRENVILLE TO CAPE SHOALWATER...AND FOR THE
WEST ENTRANCE TO THE STRAIT OF JUAN DE FUCA.

A WEAK WARM FRONT WILL BRUSH MAINLY THE COASTAL WATERS ON WED. THIS
FRONT WILL GIVE AREAS OF SMALL CRAFT ADVISORY SOUTH TO SOUTHEAST
WINDS TO PORTIONS OF THE COASTAL WATERS LATER WED.

ANOTHER FRONTAL SYSTEM WILL STALL JUST OFFSHORE THU AND FRI...MOVING
INLAND SAT. ALBRECHT

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY UNTIL 9 PM PST THIS EVENING 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-WEST ENTRANCE U.S. WATERS STRAIT OF
     JUAN DE FUCA.

&&

$$

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