Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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569
FXUS66 KSEW 062204
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
304 PM PDT FRI MAY 6 2016

.SYNOPSIS...HIGH PRESSURE ALOFT WILL PROVIDE SUNSHINE AND ABOVE
NORMAL TEMPERATURES SATURDAY. A TROUGH WILL INDUCE COOLER ONSHORE
FLOW SATURDAY NIGHT AND SUNDAY WITH SOME DRIZZLE OR SHOWERS
POSSIBLE. AN UPPER RIDGE WILL BRING DRY AND WARMER WEATHER NEXT
WEEK.


&&

.SHORT TERM...AN UPPER RIDGE WILL BRING ONE MORE DRY SUNNY DAY
SATURDAY...ABOUT THE SAME AS TODAY. AN UPPER TROUGH WILL PASS TO
THE NORTH SATURDAY NIGHT AND SUNDAY. THIS WILL BRING A FEW SHOWERS
BUT THE MAIN IMPACT WILL BE TO USHER IN MARINE AIR AND COOL HIGHS
BACK TO NEAR NORMAL. MORNING CLOUDS SHOULD GIVE WAY TO PARTIAL
AFTERNOON SUNSHINE SUNDAY. A FEW SHOWERS MIGHT LINGER INTO
MONDAY...MAINLY OVER THE CASCADES. OTHERWISE...AN UPPER RIDGE OVER
THE NORTHEAST PACIFIC WILL SLOWLY APPROACH WITH INCREASING
SUNSHINE AND HIGH WARMING A FEW DEGREES. SCHNEIDER

.LONG TERM...AN UPPER RIDGE OVER THE NORTHEAST PACIFIC WILL
PROVIDE GENERALLY DRY WEATHER TUESDAY THROUGH FRIDAY. HIGHS WILL
WARM INTO THE 70S OR LOWER 80S TUESDAY AND WEDNESDAY WITH PLENTYOF
SUNSHINE. THE RIDGE IS FORECAST TO WEAKEN OR EVEN RETROGRADE
SLIGHTLY THURSDAY AND FRIDAY AS AN UPPER TROUGH DROPS DOWN THE
BACK SIDE. THE GFS IS STRONGEST WITH THIS FEATURE...WITH SHOWERS
OVER THE AREA THURSDAY AND FRIDAY BUT THIS SEEMS OVERDONE. THE
DRIER ECMWF IS PREFERRED FOR NOW. FOR NOW THE THINKING IS THE
MAIN AFFECT WILL BE TO BRING SLIGHT COOLING AND PERHAPS SOME
ADDITIONAL CLOUDS BUT EVEN THAT MIGHT NOT HAPPEN IF THE ECWMF
TURNS OUT TO BE CORRECT. SCHNEIDER

&&

.AVIATION...UPPER LEVEL HIGH PRESSURE WILL DOMINATE THE REGION
TONIGHT. DRY AND STABLE NE FLOW ALOFT WILL CONTINUE THROUGH MOST OF
SATURDAY. LIGHT TO MODERATE NW FLOW ALOFT DEVELOPS SATURDAY NIGHT
ASSOCIATED WITH AN UPPER TROUGH. THE TROUGH WILL INDUCE A STRONG
ONSHORE MARINE PUSH...BRING MVFR STATUS FROM THE COAST INTO THE
WRN WA LOWLANDS AFTER MIDNIGHT ALONG WITH AREAS OF DRIZZLE THROUGH
SUNDAY MORNING.

KSEA...N WIND 8-14 KT W/ GUSTS 20 KT...EASING TO NE 6-10 KT AGAIN
AFTER SUNSET. NW WIND TO 10 KT SATURDAY...BECOMING SW SATURDAY
EVENING. JUST A FEW HIGH CLOUDS ABOVE 20K FT. THE PATTERN
REPEATS SATURDAY W/ VFR SKIES.

A STRONG ONSHORE PUSH DEVELOPS BY SATURDAY EVENING. MVFR STRATUS
ALONG THE COAST WILL SPREAD INLAND AND REACH THE TERMINAL BY EARLY
SUNDAY MORNING WITH AREAS OF DRIZZLE. CIGS MAY IMPROVE ABOVE 3K
FT SUNDAY AFTERNOON.

&&

.MARINE...SURFACE HIGH PRESSURE OFFSHORE AND LOWER PRESSURE
OVER WA WILL MAINTAIN NORTHWEST FLOW OVER THE COASTAL WATERS AND
NORTHERLY FLOW OVER THE INTERIOR THROUGH SATURDAY. A BRIEF BOUT OF
WESTERLY SMALL CRAFT WINDS MAY DEVELOP THIS EVENING IN THE
CENTRAL/EAST STRAIT W/ SMALL CRAFT NW WINDS LIKELY TO CONTINUE OVER
THE COASTAL WATERS THROUGH SATURDAY. NORTHERLY SEA-BREEZE WINDS
WILL ALSO REACH LOW-END SMALL CRAFT STRENGTH OVER PUGET SOUND AND
ADMIRALTY INLET UNTIL SUNSET THIS EVENING.

ONSHORE FLOW WILL STRENGTHEN SATURDAY AFTERNOON AND SATURDAY NIGHT AS
A STRONG MARINE PUSH DEVELOPS. WESTERLY GALES ARE LIKELY IN THE
CENTRAL STRAIT OF JUAN DE FUCA AND EAST ENTRANCE STRAIT. A GALE
WARNING IS UP...WITH A FORECAST OF 30 TO 40 KT WINDS. SMALL CRAFT
ADVISORY WINDS ARE LIKELY ALL OTHER MARINE ZONES EXCEPT PUGET SOUND
AND HOOD CANAL.

ONSHORE FLOW CONTINUES SUNDAY BUT GRADUALLY WANES. THE FLOW BECOMES
LIGHTER MONDAY THROUGH MID WEEK. DTM

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY UNTIL 5 AM PDT SUNDAY 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.

     SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO MIDNIGHT PDT
     TONIGHT FOR CENTRAL U.S. WATERS STRAIT OF JUAN DE FUCA-EAST
     ENTRANCE U.S. WATERS STRAIT OF JUAN DE FUCA.

     GALE WARNING FROM 2 PM SATURDAY TO 3 AM PDT SUNDAY FOR CENTRAL
     U.S. WATERS STRAIT OF JUAN DE FUCA-EAST ENTRANCE U.S.
     WATERS STRAIT OF JUAN DE FUCA.

     SMALL CRAFT ADVISORY UNTIL 9 PM PDT THIS EVENING FOR ADMIRALTY
     INLET-PUGET SOUND AND HOOD CANAL.

&&

$$

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