Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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FXUS66 KSEW 070454
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
854 PM PST SAT FEB 6 2016

.SYNOPSIS...A WEAK WARM FRONT WILL CLIP THE COAST AND NORTH CASCADES
ON SUNDAY. EXPECT DRY AND MILD WEATHER EARLY NEXT WEEK AS A STRONG
RIDGE BUILDS OVER THE PACIFIC NORTHWEST. THE RIDGE WILL SHIFT EAST
BY WEDNESDAY OPENING THE DOOR TO MORE FRONTAL SYSTEMS BEGINNING
WEDNESDAY NIGHT.

&&

.SHORT TERM...SKIES HAVE CLEARED A LITTLE THIS EVENING WHICH HAS
ALLOWED TEMPERATURES TO DROP INTO THE 30S MANY AREAS WITH SOME
PATCHY FOG ALREADY FOR THE SOUTH SOUND AND RIVER VALLEYS.

AN UPPER RIDGE WILL BEGIN TO BUILD OVER THE AREA ON SUNDAY WITH A
WARM FRONT CLIPPING THE REGION FOR A CHANCE OF RAIN COAST AND
NORTH. MODELS DIFFER ON HOW MUCH AND HOW WIDESPREAD THIS RAIN WILL
BE. GIVEN THE HIGH 500 MB HEIGHTS AND INCREASING LOW LEVEL
OFFSHORE FLOW IT SEEMS LIKE IT SHOULD NOT BE MUCH OF AN EVENT BUT
THE 00Z GFS AND NAM INSIST A LITTLE LIGHT RAIN WILL SPREAD OVER
MOST OF THE AREA FOR A FEW HOURS AROUND MIDDAY.

THE UPPER RIDGE WILL STRENGTHEN OVER THE AREA ON TUESDAY FOR DRY
AND MOSTLY SUNNY WEATHER. HIGHS WILL WARM INTO THE MID 50S TO
LOWER 60S. THE UPPER RIDGE WILL KEEP THE WEATHER DRY ON TUESDAY
BUT IT WILL BE SHIFTING INLAND...OPENING THE DOOR FOR A FEW MORE
CLOUDS AND A LITTLE COOLING. SCHNEIDER

.LONG TERM...PREVIOUS DISCUSSION...THE UPPER LEVEL RIDGE WILL
SHIFT FARTHER INLAND ON WEDNESDAY AS AN UPPER LEVEL LOW FORMS OVER
THE NE PAC. A WEAK WARM FRONT MAY BRING A CHANCE OF RAIN WEDNESDAY
NIGHT...BUT MODELS ARE BACKING OFF SLIGHTLY ON THIS SYSTEM. RAIN
IS LIKELY ON FRIDAY AS ANOTHER FRONTAL SYSTEM MOVES INLAND. AN
UPPER LEVEL TROUGH WILL MAINTAIN SHOWERS AND COOLER WEATHER INTO
NEXT WEEKEND. 33

&&

.AVIATION...SOME SCATTERED CLOUDS OUT THERE...WITH THE THICKEST
CONCENTRATION IN THE SOUTHWESTERN PORTION OF THE AREA...MAINLY SOUTH
OF A KSEA-KHQM LINE. UPPER LEVEL WINDS REMAINING NORTHWESTERLY
TONIGHT AS UPPER LEVEL RIDGE CONTINUES MOVING EASTWARD...THEN
TURNING WESTERLY TOMORROW AFTERNOON AS RIDGE AXIS ENTERS THE AREA.

LOWER LEVELS WILL CONTINUE TO DRY OUT AS EASTERLY SURFACE WINDS
CONTINUE...THUS ALLOWING CIGS TO REMAIN VFR INTO SUNDAY MORNING.
INCOMING MOISTURE HOWEVER MAY BRING CIGS DOWN TO MVFR IN SOME
LOCATIONS SUNDAY AFTERNOON. MODELS HINTING AT A THREAT FOR SOME
PRECIP TO GO WITH THOSE FALLING CIGS...BUT LOOKS INCREDIBLY
SCATTERED AND QUICK MOVING AT BEST. THIS IS PRESENT IN INHERITED
TAFS...BUT MAY WARRANT RE-EVALUATION FOR 06Z ISSUANCE...PARTICULARLY
DUE TO A FULL 24 HOUR PERIOD OF DRYING AT LOWER LEVELS. SMR

KSEA...VFR CONDITIONS WITH SOME MID AND HIGH LEVEL CLOUDS TONIGHT
AND INTO SUNDAY MORNING. CIGS WILL GRADUALLY COME DOWN SUNDAY IN
RESPONSE TO MOISTURE AND THE TAIL END OF A WARM FRONT BRUSHING BY.
CIGS OF 020-040 SHOULD BE EXPECTED FROM 18Z SUN MORNING TO ABOUT 03Z
SUN EVNG. CLEARING AFTERWARD ON SUN EVNG. SMR/HANER

&&

.MARINE...HIGH PRES WILL DEVELOP EAST OF THE CASCADES TONIGHT AND
PERSIST FOR MUCH OF THE WEEK AHEAD. THIS WILL LEAD TO VARYING
DEGREES OF OFFSHORE FLOW THROUGH AT LEAST TUE NGT.

THE TAIL END OF A WARM FRONT WILL BRUSH THE COASTAL WATERS LATE
TONIGHT AND SUNDAY...LEADING TO INCREASING E/SE WIND FOR THE
COAST AND WEST ENTRANCE. HAVE HOISTED SMALL CRAFT ADVISORIES
STARTING LATER TONIGHT FOR THE INCREASE IN WIND.

HAZARDOUS SEAS OVER THE COASTAL WATERS CONTINUE TO SUBSIDE AND WILL
FALL BELOW CRITERIA BY 10 PM THIS EVENING...THUS ADVISORY WILL BE
ALLOWED TO EXPIRE. HANER/SMR

&&

.HYDROLOGY...RIVER FLOODING IS NOT EXPECTED IN THE NEXT 7 DAYS.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY UNTIL 3 PM PST SUNDAY FOR COASTAL WATERS
     FROM CAPE FLATTERY TO JAMES ISLAND 10 TO 60 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 FOR HAZARDOUS SEAS UNTIL 10 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-COASTAL
     WATERS FROM POINT GRENVILLE TO CAPE SHOALWATER OUT 10 NM.

     SMALL CRAFT ADVISORY UNTIL 7 PM PST SUNDAY FOR COASTAL WATERS
     FROM CAPE FLATTERY TO JAMES ISLAND OUT 10 NM.

     SMALL CRAFT ADVISORY FROM 2 AM TO 7 PM PST SUNDAY FOR WEST
     ENTRANCE U.S. WATERS STRAIT OF JUAN DE FUCA.

&&

$$

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