Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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000
FXUS66 KSEW 061724
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
930 AM PST SAT FEB 6 2016

.SYNOPSIS...A FEW SHOWERS WILL LINGER OVER THE AREA THIS MORNING. 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...ONSHORE FLOW CONTINUES THIS MORNING WITH ISOLATED TO
SCATTERED SHOWERS OVER THE CWA. SHOWERS WILL DIMINISH THIS AFTERNOON
AS A WEAK UPPER LEVEL RIDGE NUDGES IN AND ONSHORE FLOW EASES. EXPECT
HIGHS NEAR 50 DEGREES TODAY. THE CURRENT FORECAST IS ON TRACK.

THE UPPER LEVEL RIDGE WILL FLATTEN OVER WESTERN WA ON SUNDAY WHILE A
WARM FRONT MOVES INTO SOUTHERN BRITISH COLUMBIA. LIGHT PRECIP MAY
CLIP THE COAST/OLYMPICS AND NORTH CASCADES FOR A CHANCE OF RAIN.

THE UPPER LEVEL RIDGE WILL STRENGTHEN OVER THE PAC NW ON MONDAY FOR
DRY AND MILD WEATHER. OFFSHORE FLOW WILL INCREASE WITH SUNNY SKIES
EXPECTED. TEMPS WILL BUMP UPWARDS A FEW DEGREES WITH HIGHS IN THE
50S TO LOWER 60S. 33

.LONG TERM...PREVIOUS DISCUSSION...UPPER LEVEL RIDGE STARTS SHIFTING
EAST ON TUESDAY BUT THE LOW LEVEL OFFSHORE FLOW CONTINUES RESULTING
IN ANOTHER VERY WARM DAY. ONCE AGAIN THE COAST WILL BE THE WARMEST
LOCATION. MODEL SOLUTIONS START TO DIVERGE AFTER TUESDAY WITH THE
GFS BRINGING A VERY WEAK SYSTEM INTO THE AREA ON WEDNESDAY. THE
ECMWF LEAVES THIS SYSTEM OFFSHORE AND THE CANADIAN IS A COMPROMISE
WITH SOME RAIN ON THE COAST. LITTLE CONSISTENCY IN THE 00Z MODEL
SOLUTIONS CONTINUE FOR WEDNESDAY NIGHT AND THURSDAY WITH THE ECMWF
BRINGING A FRONT THROUGH THE AREA WEDNESDAY NIGHT WHILE THE GFS AND
CANADIAN HAVE THE SYSTEM MOVING THROUGH ON THURSDAY. THERE IS BETTER
CONSENSUS ON FRIDAY WILL ALL OF THE MODELS INDICATING SOME
PRECIPITATION. CURRENT FORECAST HAS CHANCE POPS WEDNESDAY NIGHT
THROUGH THURSDAY NIGHT WITH LIKELY POPS ON FRIDAY. WITH THE LACK OF
MODEL CONSISTENCY WILL STAY WITH THIS SCENARIO IN THE MORNING
FORECAST PACKAGE. FELTON

&&

.AVIATION...WILL BE A GRADUAL IMPROVING TREND TODAY IN TERMS OF
LIFTING AND SCATTERING OF IFR/MVFR CLOUD CIGS. IMPROVEMENT WILL BE
SLOW UNTIL 21Z...THEN THE IMPROVING TREND WILL ACCELERATE AFTER
THAT...WITH VFR CONDITIONS FOR THE LATE AFTN AND EVNG.
OTHERWISE...UPPER LEVEL HIGH PRES WILL BUILD IN FROM THE SOUTH...
AND LOW-LEVEL WINDS WILL BECOME WEAKLY OFFSHORE TONIGHT. ON
SUNDAY...WARM ADVECTION LIFT AND MOISTURE ON THE PERIPHERY OF THE
DEVELOPING UPPER RIDGE WILL BRING CLOUDS AND LOTS OF MVFR CIGS ON
SUNDAY AFTN...WITH SOME -RA 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...IFR CIGS BELOW 020 AS OF 17Z WILL BE SHORT-LIVED...BECOMING
SCATTERED BY 19Z. CIGS IN THE 020-030 RANGE WILL BE POSSIBLE UNTIL
ABOUT 22Z. AFTER THAT...A DRYING EASTERLY COMPONENT TO THE SFC WIND
WILL DEVELOP AND QUICKLY DISSIPATE ANY REMAINING CLOUDS BELOW 050.
MERELY SOME MID-LEVEL CLOUDS FOR THE EVENING RUSH. ON SUNDAY...CIGS
WILL GRADUALLY COME DOWN IN RESPONSE TO MOISTURE AND LIFT AS A
WARMER AIR MASS SPREAD IN. CIGS OF 020-040 SHOULD BE EXPECTED ON
SUNDAY AFTERNOON.HANER

&&

.MARINE...GRADIENTS HAVE REALLY WEAKENED OVER THE PAST 6 HOURS...AND
NO SMALL CRAFT WINDS ARE OBSERVED ANY MORE. HAVE THEREFORE DROPPED
ALL WIND-RELATED MARINE ADVISORIES. HAZARDOUS SEAS OVER THE COASTAL
WATERS WILL GRADUALLY SUBSIDE TODAY AND FALL BELOW 10 FEET TONIGHT.

HIGH PRES WILL DEVELOP EAST OF THE CASCADES TONIGHT...WITH LIGHT TO
MODERATE OFFSHORE FLOW FROM SUNDAY THROUGH TUE NGT. SMALL CRAFT
ADVISORY CONDITIONS ARE POSSIBLE AT TIMES SUNDAY ONWARD NEAR GAPS IN
THE TERRAIN OVER THE COASTAL WATERS AND POSSIBLY IN THE OUTER
PORTIONS OF THE COASTAL WATERS. HANER

&&

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

&&

.CLIMATE...UPON FURTHER REVIEW IT TURNS OUT SEATTLE SET A RECORD
FOR THE MOST PRECIPITATION FROM DECEMBER 1ST THROUGH JANUARY 31ST
WITH 18.66 INCHES. THE OLD RECORD WAS 18.51 INCHES SET IN
2005-06. FELTON

&&

.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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