Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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662
FXUS66 KSEW 062323
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
330 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...PRESSURE GRADIENTS ARE TURNING OFFSHORE THIS AFTERNOON
AND SHOWERS HAVE ENDED ACROSS WESTERN WA. SKIES WILL REMAIN MOSTLY
CLOUDY TONIGHT WITH LOWS NEAR 40.

A DIRTY RIDGE WILL SET UP OVER THE REGION ON SUNDAY AS A WARM FRONT
MOVES INTO SOUTHERN BRITISH COLUMBIA. THIS FRONT MAY CLIP WESTERN WA
FOR A CHANCE OF RAIN ON THE OLYMPIC PENINSULA AND NORTH CASCADES.
BUT WITH OFFSHORE FLOW AND 500 MB HEIGHTS IN THE 570S NOT EXPECTING
MUCH IN QPF.

THE UPPER LEVEL RIDGE WILL STALL OVER THE PAC NW MONDAY AND TUESDAY
FOR DRY AND MILD WEATHER ACROSS WESTERN WA. OFFSHORE FLOW WILL
INCREASE WITH MOSTLY CLEAR SKIES EXPECTED. TEMPS WILL BUMP UPWARDS A
FEW DEGREES WITH HIGHS IN THE 50S TO LOWER 60S...WITH MID 60S
POSSIBLE AT THE COAST. 33

.LONG TERM...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

&&

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

&&

.AVIATION...CIGS OF 025-035 IN THE CENTRAL SOUND REGION (SEA-BFI-PAE-
PWT) WILL SOON QUICKLY CLEAR AWAY AS A DRYING EASTERLY COMPONENT OF
THE SFC WIND DEVELOPS...AND LOW-LEVEL LIFT TURNS TO LOW-LEVEL
SUBSIDENCE FOR THIS EVNG. THIS WILL LEAVE WRN WA WITH VFR CONDS THIS
EVNG AND OVERNIGHT...WITH SCT-BKN MID-LEVEL CLOUDS AOA 10000 FT MSL.
ON SUNDAY...WARM ADVECTION LIFT AND MOISTURE ON THE PERIPHERY OF THE
DEVELOPING UPPER RIDGE WILL BRING CLOUDS AND SOME MVFR CIGS ON
SUNDAY AFTN...WITH SOME -RA POSSIBLE OVER THE OLYMPIC PENINSULA AND
THE INTERIOR NORTH OF SEATTLE. LOW- LEVEL AIR MASS DRYING THROUGH
TONIGHT...THEN MOISTENING ON SUNDAY. MODERATE WEST WINDS ALOFT.

KSEA...MVFR CIGS IN THE 025-030 RANGE WILL CLEAR OUT ANY TIME
NOW...LEAVING A VFR EVNG AND OVERNIGHT WITH MID-LEVEL CLOUDS. ON
SUNDAY...CIGS WILL GRADUALLY COME DOWN 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.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 ARE SUBSIDING NICELY. SEAS
HAVE DROPPED BELOW 10 FEET AT BUOY 87 AT THE WEST ENTRANCE...AND ARE
AT 10-11 FEET AT BUOY 41. ADVISORIES HAVE BEEN ADJUSTED ACCORDINGLY.
HANER

&&

.SEW WATCHES/WARNINGS/ADVISORIES...

WA...NONE.

PZ...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS COAST AND WEST
     ENTRANCE.

     SMALL CRAFT ADVISORY FOR ROUGH GRAYS HARBOR BAR.

&&

$$

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