Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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000
FXUS66 KSEW 281555
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
900 AM PDT FRI AUG 28 2015

.SYNOPSIS...A WEAK FRONT MOVED THROUGH WESTERN WASHINGTON THIS
MORNING. A STRONGER FRONTAL SYSTEM WILL SWEEP THROUGH THE AREA
SATURDAY. AN UPPER TROUGH WILL AFFECT THE REGION NEXT WEEK.

&&

.SHORT TERM...A WEAK FRONT MOVED THROUGH WESTERN WA THIS MORNING AND
THE PRECIP HAS BROKEN UP TO SCATTERED SHOWERS. SATURDAY WILL SEE
PERIODS OF RAIN AND BLUSTERY CONDITIONS AS A STRONGER FRONTAL SYSTEM
MOVES THROUGH WESTERN WA. THE 12Z GFS SHOWS A 1008 MB LOW NEAR 39N
132W THIS MORING DEEPENING TO 993 MB AND TRACKING JUST OFF THE COAST
SATURDAY MORNING. THERE WILL BE GALE WARNINGS IN EFFECT FOR THE
MARINE AREAS SATURDAY WITH WIND ADVISORIES OVER LAND.

.LONG TERM...COOL UNSETTLED CONDITIONS WILL PERSIST OVER THE AREA
WITH AN UPPER LEVEL TROUGH OVER THE REGION THROUGH THE WEEK. LOOKING
AT THE 06Z GFS...SHORTWAVE TROUGHS MOVING THROUGH THE BROAD REGIONAL
TROUGH REINFORCE THE COOL SHOWERY AIR MASS ON ABOUT WED AND AGAIN
AROUND FRIDAY NIGHT AND SATURDAY. BELOW NORMAL TEMPS AND ABOVE
NORMAL PRECIP IS LIKELY WITH SHOWERS AND SOME PARTLY SUNNY PERIODS.

&&

.AVIATION...A WEAK FRONT MOVING THROUGH THE INTERIOR OF WESTERN
WASHINGTON THIS MORNING WILL KEEP LOW AND MID LEVEL CLOUDS WITH
SCATTERED SHOWERS OVER THE AREA THIS MORNING WITH SOME IMPROVEMENT
BEHIND THE FRONT. MVFR CIGS WILL IMPROVE TO VFR BY LATE MORNING. THE
AIR MASS WILL REMAIN MOIST AND GENERALLY STABLE WITH SOUTHWEST FLOW
ALOFT.

KSEA...CEILINGS HAVE BEGUN TO SHOW IMPROVEMENT. EXPECT MVFR CIGS TO
IMPROVE TO VFR OVER THE NEXT TWO HOURS. OVERNIGHT CIGS WILL LIKELY
LOWER AGAIN BY AROUND DAYBREAK TO MVFR LEVELS. SOUTHERLY WINDS 4-8
KNOTS WILL BECOME LIGHT NORTHERLY TONIGHT.

&&

.MARINE...SOUTHERLY WINDS OVER THE COASTAL WATERS WILL BECOME
SOUTHWESTERLY THIS MORNING AND EASE OVER THE COASTAL WATERS AND WEST
ENTRANCE STRAIT OF JUAN DE FUCA AS A WEAK SURFACE FRONT MOVES
INLAND. A STRONGER FRONT WILL MOVE THROUGH THE WATERS SATURDAY WITH
GALE FORCE WINDS LIKELY FOR MOST WATERS SATURDAY MORNING THROUGH
MUCH OF THE DAY. A SET OF WEAKER FRONTAL WAVES WILL MOVE THROUGH
AREA WATERS SUNDAY AND AGAIN MONDAY HELPING TO BOOST WINDS AND SEAS.
THESE SYSTEMS WILL NOT BE AS STRONG AS SATURDAYS FRONT...BUT WILL
LIKELY BRING SMALL CRAFT ADVISORY CRITERIA TO THE COASTAL WATERS AS
WELL AS PARTS OF THE INLAND AREAS.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...GALE WATCH FROM LATE TONIGHT THROUGH SATURDAY AFTERNOON FOR
     CENTRAL U.S. WATERS STRAIT OF JUAN DE FUCA-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.

     GALE WATCH FROM SATURDAY MORNING THROUGH SATURDAY EVENING FOR
     ADMIRALTY INLET-COASTAL WATERS FROM CAPE FLATTERY TO JAMES
     ISLAND 10 TO 60 NM-COASTAL WATERS FROM CAPE FLATTERY TO
     JAMES ISLAND OUT 10 NM-WEST ENTRANCE U.S. WATERS STRAIT OF
     JUAN DE FUCA.

     SMALL CRAFT ADVISORY FROM 5 AM EARLY THIS MORNING TO 1 PM PDT
     THIS AFTERNOON 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-WEST ENTRANCE U.S.
     WATERS STRAIT OF JUAN DE FUCA.

     GALE WATCH FROM LATE TONIGHT THROUGH SATURDAY EVENING FOR EAST
     ENTRANCE U.S. WATERS STRAIT OF JUAN DE FUCA-NORTHERN INLAND
     WATERS INCLUDING THE SAN JUAN ISLANDS-PUGET SOUND AND HOOD
     CANAL.

&&

$$

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