Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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FXUS66 KSEW 251025
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
325 AM PDT MON APR 25 2016

.SYNOPSIS...MOSTLY DRY WEATHER WILL PREVAIL THIS WEEK. WEAK
WEATHER SYSTEMS WILL BRING A CHANCE OF SHOWERS AT TIMES...MAINLY
TODAY...WEDNESDAY...AND FRIDAY.

&&

.SHORT TERM...A WEAK UPPER TROUGH WILL BE OVER THE AREA TODAY.
LINGERING MOISTURE AND INSTABILITY WILL KEEP A SMALL CHANCE OF
SHOWERS IN THE FORECAST FOR TODAY. THE REMNANTS OF A PUGET SOUND
CONVERGENCE ZONE ARE CURRENLTY LINGERING DIRECTLY OVER SEATTLE.
MESO MODELS SHOWS THESE SHOWERS FADING AWAY IN THE NEXT FEW HOURS
BUT THEN ANOTEHR WEAK CONVERGENCE ZONE FORMING TO THE NORTH AND
SAGGING SOUTH THROUGH THE METRO AREA TODAY.

THE AIR MASS WILL BECOME STABLE AND THE SHOWER THREAT SHOULD END
TONIGHT AS AN UPPER RIDGE MOVES OVER THE AREA. THE RIDGE WILL
SHIFT INLAND TUESDAY WITH A FRONT APPORACHING FROM THE WEST. A
LITTLE RAIN COULD REACH THE COAST LATE IN THE DAY BUT MOST OF THE
AREA WILL BE DRY WITH INCREASING MID AND HIGH CLOUDS.

THE FRONT WILL MOSTLY FALL APART JUST OFF THE COAST TUESDAY NIGHT
AND WEDNESDAY. THERE MIGHT BE A FEW SHOWERS FROM THE REMNANTS OF
THIS FRONT BUT NOTHING SIGINIFCANT. SCHNEIDER

.LONG TERM...WEAK HIGH PRESSURE ALOFT SHOULD RESULT IN A DRY DAY
THURSDAY. AN UPPER SHORT WAVE WILL BRING SOME SHOWERS ON FRIDAY.
RECENT MODELS HAVE TRENDED A LITTLE WETTER WITH THIS SYSTEM BUT IT
STILL DOES NOT LOOK LIKE MUCH.

MODELS ARE COMING INTO AGREEMENT SHOWING AN UPPER RIDGE BUILDING
OVER THE AREA NEXT WEEKEND FOR MOSTLY SUNNY WEATHER. HIGHS COULD
WARM TO NEAR 70 BY SUNDAY. SCHNEIDER

&&

.AVIATION...A WEAKENING UPPER LEVEL TROF OVER THE AREA WILL MOVE
SLOLY E DURING THE DAY TODAY. LIGHT AND VARIABLE FLOW ALOFT WILL
BECOME NLY AND STRENGTHEN. THE LOW LEVEL FLOW WILL REMAIN
ONSHORE. ANTICIPATE AREAS OF MVFR CIGS /2-3K FT/...MAINLY WITH
SHOWERS...THIS MORNING.

KSEA...ANTICIPATE OCNL MVFR CIGS /2500-3000 FT/ THIS MORNING.
OTHERWISE...VFR CONDITIONS WILL PREVAIL OVER THE TERMINAL. LIGHT
AND VARIABLE WINDS WILL BECOME W OR NW 5-10 KT THIS AFTERNOON.

&&

.MARINE...HIGH PRES OVER THE OFFSHORE WATERS WITH LOWER PRES E OF THE
CASCADES WILL KEEP THE FLOW ONSHORE OR WESTERLY TODAY. THE AREA OF
HIGH PRES WILL SHIFT ONTO THE WASHINGTON COAST TONIGHT AS A
FRONTAL SYSTEM APPROACHES THE OFFSHORE WATERS. THIS WILL CAUSE THE
ONSHORE FLOW TO WEAKEN. EXPECT A WEAKENING OCCLUDED FRONT TO
APPROACH THE COASTAL WATERS TUE EVENING.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY UNTIL 6 AM PDT EARLY THIS MORNING FOR
     CENTRAL U.S. WATERS STRAIT OF JUAN DE FUCA-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-EAST ENTRANCE U.S. WATERS STRAIT OF
     JUAN DE FUCA.

     SMALL CRAFT ADVISORY FOR ROUGH BAR UNTIL 5 PM PDT THIS AFTERNOON
     FOR GRAYS HARBOR BAR.

&&

$$

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