Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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000
FXUS66 KSEW 061152
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
352 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...SATELLITE IMAGERY SHOWS LAST NIGHTS COLD FRONT IS
ALREADY OUT OF THE STATE. POST FRONTAL SHOWERS STILL EVIDENT
OFFSHORE BUT WITH SOME WEAK WARM ADVECTION GOING ON WITH THE
APPROACH OF THE NEXT WARM FRONT THE SHOWERS ARE DECREASING.
DOPPLER RADAR SHOWS OVER THE INTERIOR WESTERLY FLOW ALOFT IS
KEEPING THE CENTRAL SOUND RAIN SHADOWED WITH AN AREA OF
CONVERGENCE IN THE CASCADES NORTH OF STEVENS PASS AND PLENTY OF
SHOWERS WEST OF PUGET SOUND AT 330 AM. TEMPERATURES AT 3 AM WERE
IN THE MID 30S TO MID 40S.

TODAY LOOKS TO BE A TRANSITION DAY WITH AN UPPER LEVEL RIDGE
STARTING TO BUILD OFF THE COAST AHEAD OF THE WARM FRONT WHICH IS
CURRENTLY NEAR 140W. SHOWER ACTIVITY WILL DECREASE THIS MORNING
AND BECOME CONFINED TO THE MOUNTAINS THIS AFTERNOON. LOW LEVEL
ONSHORE FLOW THIS MORNING WILL BECOMING LIGHT LATER THIS MORNING
AND THIS AFTERNOON. STILL SOME SLIGHTLY COOL AIR LEFT IN THE WAKE
OF YESTERDAYS FRONT SO EVEN WITH A LITTLE SUNSHINE HIGH
TEMPERATURES WILL BE NEAR NORMAL...AROUND 50 DEGREES.

UPPER LEVEL RIDGE KEEPS BUILDING BETWEEN 130W AND THE COASTLINE
TONIGHT WHILE THE WARM FRONT CONTINUES TO MOVE NORTHEAST. WITH THE
APPROACHING WARM FRONT LOWERING SURFACE PRESSURES OFFSHORE LOW
LEVEL FLOW GOING OFFSHORE. WARM FRONT CLOSE ENOUGH TO SPREAD SOME
MID/HIGH LEVEL MOISTURE OVER THE AREA OVERNIGHT KEEPING THE
WORDING IN THE FORECAST MOSTLY CLOUDY. THERE IS THE POTENTIAL FOR
A COLORFUL SUNRISE SUNDAY MORNING. LOWS OVERNIGHT IN THE 30S TO
MID 40S.

UPPER LEVEL RIDGE CONTINUES TO BUILD ON SUNDAY AND SHIFT EAST OVER
WESTERN WASHINGTON. 500 MB HEIGHTS BY 00Z MONDAY IN THE UPPER 570
DMS TO LOWER 580 DMS. STILL A CHANCE THE WARM FRONT MOVING OVER
THE RIDGE COULD BRING SOME LIGHT PRECIPITATION TO THE NORTH COAST
AND NORTH CASCADES. WILL LEAVE CHANCE POPS IN THE FORECAST FOR
THESE LOCATIONS. FOR THE REMAINDER OF THE AREA PARTLY SUNNY/MOSTLY
CLOUDY SKIES WITH THE MID AND HIGH LEVEL CLOUD COVER. HIGHS WILL
BE IN THE 50S.

WARM FRONT MOVING WELL NORTH OF THE AREA SUNDAY NIGHT AS THE RIDGE
CONTINUES TO BUILD. UPPER LEVEL RIDGE RIGHT OVER WESTERN
WASHINGTON IN MONDAY WITH 500 MB HEIGHTS CONTINUE TO INCREASE A
TOUCH. LOW LEVEL FLOW REMAINS OFFSHORE. END RESULT WILL BE A WARM
DAY WITH TEMPERATURES ANYWHERE FROM 5 TO 15 DEGREES ABOVE NORMAL.
THE RECORD HIGH OF 61 DEGREES AT KUIL WILL HAVE A GOOD CHANCE OF
BEING BROKEN WITH HIGHS ON THE COAST IN THE LOWER TO MID 60S. 50S
AND LOWER 60S WILL BE COMMON OVER THE REST OF WESTERN
WASHINGTON...AROUND WHAT THE NORMAL HIGHS WOULD BE FOR THE MIDDLE
OF APRIL.

.LONG TERM...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...WESTERLY UPPER LEVEL FLOW WILL TURN NORTHWESTERLY AS
AN UPPER LEVEL TROF STARTS TO MAKE ITS WAY EAST OF THE AREA.
SCATTERED SHOWERS STILL PRESENT ON CURRENT RADAR IMAGERY.

CIGS REMAIN VFR TO MVFR AND ARE GENERALLY EXPECTED TO REMAIN THAT
WAY AS UPPER LEVEL RIDGING STARTS TO BUILD INTO THE AREA.
HOWEVER...WITH SOME SCATTERED SHOWERS STILL OUT THERE...MAY SEE CIGS
DIP INTO MVFR TO IFR RANGE IN LOCATIONS THAT SEE PRECIP. AS UPPER
LEVEL RIDGING CONTINUES TO BUILD OVER WESTERN WASHINGTON...EXPECTING
DRYING CONDITIONS STARTING THIS AFTERNOON AND CONTINUING INTO
SUNDAY. SMR

KSEA...CIGS GENERALLY VFR...HOWEVER THERE IS A PATCH OF SHOWERS
HEADING TOWARD KSEA WHICH MAY LOWER CIGS TO MVFR AS IT PASSES BY.
TIMING ON THIS LOOKS TO BE BY 12Z. OTHERWISE...VFR CONDITIONS
EXPECTED TO REMAIN DOMINANT. WINDS TO REMAIN SOUTHERLY THIS MORNING
AND INTO THE AFTERNOON BEFORE SHIFTING EASTERLY BY EVENING. SPEEDS
WILL GRADUALLY DECREASE...10-14 KTS WITH OCCASIONAL GUSTS EARLY THIS
MORNING...GENERALLY 8-12 KTS BY LATE MORNING AND STEADYING OFF AT 4-
7 KTS BY LATE AFTERNOON. SMR

&&

.MARINE...CURRENT BATCH OF GALES AND SMALL CRAFT ADVISORIES WILL BE
GENERALLY LEFT INTACT WITH MORNING FORECAST. COASTAL WATERS ARE JUST
SHY OF SMALL CRAFT...TOO CLOSE FOR COMFORT...AND CENTRAL AND EAST
STRAIT ARE SIMILARLY JUST SHY OF GALE. REMAINING WATERS HAVE
LOCATIONS MEETING SMALL CRAFT ADVISORY WINDS...SO TIMING ON
HEADLINES LOOKS OKAY AT THIS TIME. DID HOIST A SMALL CRAFT TO FOLLOW
THE GALE WARNING FOR CENTRAL STRAIT...WHILE EASTERN STRAIT LOOKS
LIKE IT MIGHT BE OKAY FOR NO ADDITIONAL PRODUCTS.

SEAS WILL CONTINUE TO SUBSIDE THROUGHOUT THE DAY TODAY...PUTTING TO
REST ANY CONCERNS REGARDING SURF OR BEACH EROSION FOR THE TIME BEING.

ONSHORE FLOW WILL CONTINUE TO DIMINISH THROUGH THE DAY TODAY AS A
RIDGE OF HIGH PRESSURE BUILDS INTO THE WATERS. THE RIDGE WILL SHIFT
EAST OF THE CASCADES ON SUNDAY RESULTING IN LIGHT TO MODERATE
OFFSHORE FLOW THAT WILL PERSIST INTO THE MIDDLE OF NEXT WEEK. 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. SMR

&&

.HYDROLOGY...THE NORTH FORK OF THE SKOKOMISH RIVER IS RECEDING
AND THE SOUTH FORK IS CRESTING EARLY THIS MORNING. THE MAIN STEM
OF THE SKOKOMISH IS SLOWLY RISING BUT IS NEARLY A FOOT BELOW FLOOD
STAGE. WITH LITTLE RAIN EXPECTED TODAY WILL END THE WATCH FOR
MASON COUNTY WITH THIS FORECAST PACKAGE.

RIVER FLOODING IS NOT EXPECTED IN THE NEXT 7 DAYS.

IN ADDITION WITH JUST A FEW SHOWERS LEFT BEFORE THE WEATHER TURNS
DRY WILL ALLOW THE LANDSLIDE THREAT STATEMENT TO EXPIRE AT 4 AM.
FELTON

&&

.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 ROUGH BAR UNTIL 4 PM PST THIS AFTERNOON
     FOR GRAYS HARBOR BAR.

     SMALL CRAFT ADVISORY UNTIL 10 AM PST THIS MORNING 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-WEST ENTRANCE U.S. WATERS
     STRAIT OF JUAN DE FUCA.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 10 AM THIS MORNING
     TO 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.

     GALE WARNING UNTIL 4 AM PST EARLY THIS MORNING FOR CENTRAL U.S.
     WATERS STRAIT OF JUAN DE FUCA-EAST ENTRANCE U.S. WATERS
     STRAIT OF JUAN DE FUCA.

     SMALL CRAFT ADVISORY UNTIL 4 AM PST EARLY THIS MORNING FOR
     ADMIRALTY INLET-NORTHERN INLAND WATERS INCLUDING THE SAN
     JUAN ISLANDS-PUGET SOUND AND HOOD CANAL.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 10 AM THIS MORNING
     TO 4 PM PST THIS AFTERNOON FOR WEST ENTRANCE U.S. WATERS
     STRAIT OF JUAN DE FUCA.

     SMALL CRAFT ADVISORY UNTIL 10 AM PST THIS MORNING FOR CENTRAL
     U.S. WATERS STRAIT OF JUAN DE FUCA.

&&

$$

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