Storm Warning 7, NWS Seattle, WA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
230 AM PDT WED MAY 19 2010

.SYNOPSIS...A STRONG FRONT WILL REACH WESTERN WASHINGTON LATE THIS
AFTERNOON. A DEEP LOW PRESSURE SYSTEM WILL MOVE NORTH THROUGH THE
NEAR OFFSHORE WATERS TODAY. STRONG SOUTHERLY WINDS WILL REACH THE
COAST BY EVENING. RAIN WILL TURN TO SHOWERS TONIGHT AS THE COLD
FRONT SWEEPS THROUGH THE AREA...AND THE SNOW LEVEL WILL FALL TO PASS
LEVEL IN THE MOUNTAINS THROUGH THE END OF THE WEEK.

&&

.SHORT TERM...THE FNTL SYS FINALLY SHOWS SOME LIFE ON THE IR SATIMG
THIS MORNING WITH PLENTY OF COLD TOPS SPREADING OUT NOW FROM NEAR
THE LOW CENTER. SYS LOOKS RATHER IMPRESSIVE FOR THIS LATE IN THE
SEASON...AND THE MESOSCALE MODELS HAVE BEEN SHOWING A SHOT OF STORM
FORCE WINDS FOR THE COASTAL WATERS IN THE BENT BACK TROF THIS
EVENING. THE FCST IS PRETTY STRAIGHTFORWARD...A STORM FOR THE
COASTAL WATERS AND A MATCHING HIGH WIND WARNING FOR THE COAST. A
WIND ADVISORY SEEMS SUFFICIENT TO MATCH THE DECENT GALES OVER THE
WATERS NORTH OF SEATTLE LATER TODAY...FOR THE METRO AREA ZONE
SOUTHWARD WILL JUST HIGHLIGHT WINDY CONDITIONS DEVELOPING BY EVENING
AND THE MODELS DO NOT HAVE A GREAT DEAL OF WIND FROM SEATTLE SOUTH.
THAT SAID...THE SYSTEM HAS A NICE PUNCH OF WLY COLD AIR ALOFT INTO
NW ORE THIS EVENING AND IT MAY VERY WELL BLOW GALE PUGET SOUND AND
BE WORTH A WIND ADVISORY FOR THE METRO AREA AS WELL THIS
EVENING...SOMETHING FOR THE DAYSHIFT. HAVE LEFT OUT THE CHANCE OF
TSTMS FOR TONIGHT...IT DESTABILIZES DRAMATICALLY BHND THE FNT TODAY
AND 500MB COOLS TO ARND -32C...THIS IS ANOTHER THING FOR THE NEXT
SHIFT TO CONTEMPLATE. FINALLY...IT IS NOT OUT OF THE QUESTION THAT
THE MTNS PICK UP ENUF SNOW FOR SNOW ADVISORY AMTS TNGT AND THU...I
HAVE RATHER LIGHT AMOUNTS AND AM NOT SURE THE PASSES WILL END UP
WITH MUCH...BUT PARADISE MIGHT DO QUITE WELL. 19

.LONG TERM...COOL WITH A CHANCE OF SHOWERS AND AN UPPER TROF OVER
THE WESTERN U.S...IT COULD BE FAIRLY NICE BY SUNDAY WITH AT LEAST
PARTLY SUNNY SKIES BUT I HAVE NOT SPENT ANY TIME ON THE EXTENDED
FCST. THE LATEST GFS DOES HAVE SOME TEMPORARY HEIGHT RISES SAT NIGHT
AND SUN...ALTHOUGH GETTING BACK TO 552DAM IS STILL CHILLY. HEIGHTS
FALL OFF AGAIN EARLY NEXT WEEK. 19

&&

.AVIATION...STRONG SOUTHERLY FLOW ALOFT TODAY...BECOMING SOUTHWEST
AND EASING TONIGHT. AN UNSEASONABLY STRONG AND DEEP SURFACE LOW WILL
MOVE INTO THE OFFSHORE WATERS TODAY THEN NORTH INTO VANCOUVER ISLAND
TONIGHT. AN ASSOCIATED COLD FRONT WILL MOVE ONSHORE LATE THIS
AFTERNOON AND THIS EVENING. AIR WEAKLY UNSTABLE WITH INCREASING LOW
LEVEL MOISTURE AND RAIN SPREADING INLAND LATER TODAY.

AREAS OF MID CLOUDS OVER THE INTERIOR THIS MORNING WITH SOME LOW
CLOUDS AND SHOWERS NEAR THE COAST. LOW CLOUDS...WIND...AND RAIN WILL
INCREASE LATER TODAY AS A STRONG FRONTAL SYSTEM MOVES ONSHORE.
SHOWERS WITH LOW CEILINGS WILL LINGER TONIGHT BEHIND THE FRONT.
WINDS WILL GRADUALLY DECREASE TONIGHT BEHIND THE FRONT.

KSEA...SCATTERED LOW/MID CLOUDS FLOATING ABOUT THIS MORNING WITH A
FEW CEILINGS AROUND 4000 FEET...MAINLY NEAR SHOWERS. EXPECT
WIDESPREAD RAIN AND LOW CLOUDS TO DEVELOP THIS AFTERNOON. LIGHT
SOUTH/SOUTHEAST WIND THIS MORNING WILL BECOME MORE EASTERLY. WIND
WILL THEN BECOME SOUTHERLY...INCREASE AND BECOME GUSTY THIS
AFTERNOON AND EVENING. SCHNEIDER

&&

.MARINE...A STRONG STORM SYSTEM WILL MOVE THROUGH THE WATERS LATER
TODAY AND TONIGHT. STORM FORCE WINDS ARE POSSIBLE OVER THE COASTAL
WATERS. GALES ARE LIKELY MOST OTHER AREAS.

AFTER THAT THE REGION WILL BE UNDER THE INFLUENCE OF SEVERAL WEAK
SYSTEMS WITH VARYING DEGREES OF LIGHT TO MODERATE ONSHORE FLOW.
SCHNEIDER

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...HIGH WIND WARNING COAST...WIND ADVISORY SAN JUANS...WESTERN
WHATCOM...WESTERN SKAGIT...EVERETT AND VCNTY...ADMIRALTY INLET
AREA...WESTERN STRAIT OF JUAN DE FUCA. ALL 3 PM TIL MIDNIGHT.
PZ...STORM WARNING COAST.
    .GALE WARNING ENTRANCES TO STRAIT...ADMIRALTY INLET...AND
      NORTHER INLAND WATERS.
    .SMALL CRAFT ADVISORY CENTRAL STRAIT.

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