Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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FXUS66 KSEW 282248
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
345 PM PDT FRI AUG 28 2015

.SYNOPSIS...A STRONG FRONTAL SYSTEM WILL SWEEP THROUGH THE AREA
SATURDAY. ADDITIONAL FRONTS WILL REACH THE REGION INTO EARLY NEXT
WEEK AS A LARGE UPPER TROUGH TAKES UP RESIDENCE IN THE NORTHEAST
PACIFIC. THE TROUGH WILL LIKELY LINGER THOUGH THE END OF NEXT WEEK.

&&

.SHORT TERM...SATURDAY WILL BE WET AND WINDY AS A STRONG FRONTAL
SYSTEM MOVES THROUGH WESTERN WA. THERE ARE GALE WARNINGS IN EFFECT
FOR MOST MARINE AREAS SATURDAY AND WIND ADVISORIES OVER MOST OF THE
LOWLANDS. THE AREA ALONG THE CENTRAL STRAIT OF JUAN DE FUCA IN THE
OLYMPIC RAIN SHADOW WILL BE PROTECTED BUT MOST OF WRN WA WILL GET
A GOOD SOAKING. A COUPLE MORE FRONTAL WAVES SHOULD BRING MORE RAIN
TO THE AREA THROUGH EARLY NEXT WEEK...HEAVY RAIN IS POSSIBLE AT
TIMES IN THE OLYMPICS AND NORTH CASCADES AS RATHER WET SYSTEMS HEAD
INTO SOUTHWEST BRITISH COLUMBIA.

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

&&

.AVIATION...GENERAL IMPROVEMENT OVER THE AREA THIS AFTERNOON
WITH VFR CIGS OVER THE AREA. SATELLITE AND RADAR IMAGERY SHOWING A
FEW SHOWERS MOVING INTO THE SOUTH THIS AFTERNOON. EXPECT SCATTERED
SHOWERS TO WORK NORTHWARD INTO THE AREA THIS EVENING...WITH CIGS
REMAINING VFR. THE AIR MASS WILL REMAIN MOIST AND GENERALLY STABLE
TONIGHT WITH SOUTHWEST FLOW ALOFT. A STRONG FRONT WILL APPROACH THE
AREA FROM THE SOUTH WEST SATURDAY MORNING...BRINGING ANOTHER ROUND
OF RAIN TO THE COAST AND INLAND THROUGH THE MORNING. CIGS WILL LOWER
TO MVFR LEVELS IN THE MORNING WITH LOWER POSSIBLE ESPECIALLY ALONG
THE COAST WITH RAIN. EXPECT EASTERLY WINDS DURING THE MORNING
BECOMING SOUTHERLY AND STRENGTHENING DURING THE AFTERNOON HOURS.
SUSTAINED WINDS 20 TO 25 KT GUSTING TO 35 KT ARE POSSIBLE ESPECIALLY
DURING THE AFTERNOON HOURS.

KSEA...CEILINGS WILL REMAIN VFR WITH SHOWERS IN THE AREA THIS
EVENING. CIGS WILL LIKELY LOWER AGAIN BY AROUND DAYBREAK TO MVFR
LEVELS. SOUTHERLY WINDS 4-6 KNOTS WILL BECOME LIGHT NORTHERLY
TONIGHT...THEN SOUTHERLY BY LATE SATURDAY MORNING...STRENGTHENING TO
15-20 KNOTS GUSTING TO 30 KNOTS BY MID AFTERNOON.


&&

.MARINE...SURFACE GRADIENTS AND WINDS HAVE EASED THIS AFTERNOON.
EXPECT GRADIENTS TO BECOME OFFSHORE LATE TONIGHT AS A SURFACE LOW
APPROACHES THE COASTAL WATERS FROM THE SOUTHWEST. A STRONG FRONT
ASSOCIATED WITH THIS LOW WILL MOVE THROUGH AREA WATERS SATURDAY
BRINGING GALE FORCE SOUTHERLY WINDS TO THE COASTAL WATERS SATURDAY
MORNING FOLLOWED BY ADMIRALTY INLET...THE EAST STRAIT...THE NORTHERN
INLAND WATERS...AND PUGET SOUND BY AFTERNOON. IN ADDITION...EXPECT A
BURST OF SMALL CRAFT ADVISORY EASTERLIES THROUGH THE WEST ENTRANCE
OF THE STRAIT FOLLOWED BY SOUTHERLIES DURING THE AFTERNOON. THE
LIGHTEST WINDS WILL BE OVER THE CENTRAL STRAIT THROUGH THE DAY.
WINDS WILL EASE OVERALL SATURDAY NIGHT FOLLOWED BY A SET OF WEAKER
FRONTAL WAVES THAT WILL MOVE THROUGH THE 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 AND POSSIBLY PARTS OF THE
INLAND AREAS.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...

PZ...GALE WARNING FROM 8 AM SATURDAY MORNING THROUGH 8 PM SATURDAY
     EVENING FOR THE COASTAL WATERS.

     GALE WARNING FROM 11 AM SATURDAY MORNING THROUGH 8 PM SATURDAY
     EVENING FOR THE NORTHERN INLAND WATERS...EAST
     STRAIT...ADMIRALTY INLET...AND PUGET SOUND/HOOD CANAL.

     SMALL CRAFT ADVISORY FROM 8 AM SATURDAY MORNING TO 5 PM
     SATURDAY AFTERNOON FOR THE WEST ENTRANCE.

&&

$$

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