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000
FXUS66 KSEW 251638
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
938 AM PDT SAT MAY 25 2013

.SYNOPSIS...LOW PRESSURE ALOFT WILL REMAIN OVER THE REGION THROUGH
THE MEMORIAL DAY WEEKEND FOR CONTINUED UNSETTLED CONDITIONS. DAYTIME
TEMPERATURES WILL RUN NEAR OR A LITTLE BELOW NORMAL FOR THIS TIME
OF THE YEAR.

&&

.SHORT TERM...
AN UPPER LOW WEST OF CAPE FLATTERY RESULTED IN AN UPSWING IN
PRECIPITATION OVER THE WESTERN PART OF THE FORECAST AREA THIS
MORNING. THE GRIDDED FORECAST WAS UPDATED FOR THIS AREA TO
INCREASE POPS INTO THE CATEGORICAL RANGE...LOWER MAX TEMPS...AND
INCREASE PRECIP AMOUNTS OVER THE AFFECTED AREA. A FEW PLACES IN
THE WESTERN PART OF THE CWA WILL LIKELY SEE AMOUNTS NEAR A
QUARTER OF AN INCH TODAY. ELSEWHERE...IT WAS DRY BUT SHOWERS ARE
ANTICIPATED TO DEVELOP THIS AFTERNOON.

MEANWHILE...IT APPEARS THAT THE REGION WILL REMAIN UNDER CYCLONIC
FLOW ALOFT THROUGH THE MEMORIAL DAY WEEKEND. THIS WILL KEEP THE
WEATHER PATTERN OVER THE AREA UNSETTLED AND DAYTIME TEMPS WILL RUN
NEAR OR A LITTLE BELOW NORMAL. IN OTHER WORDS...THE IDEA OF A
TREND TOWARD LESS PRECIP...MORE SUNSHINE...AND WARMER TEMPS NOW
APPEARS DOUBTFUL.

.LONG TERM FROM THE PREV DISCUSSION...
MODELS CONTINUE THE TREND OF COOL AND SHOWERY WEATHER ACROSS
WESTERN WA THROUGH AT LEAST THE MIDDLE OF NEXT WEEK. WED MAY BE
THE WETTEST DAY AS A NEGATIVE TILT TROUGH AXIS LIFTS NORTH THROUGH
THE STATE. BUT THE MODELS ARE ADVERTISING A BREAK IN THE ACTION
STARTING THURSDAY AS A BROAD UPPER LEVEL RIDGE OVER THE NE PAC
NUDGES INLAND. THIS PATTERN MAY CONTINUE ON FRIDAY AND INTO THE
WEEKEND. SO IF THIS HOLDS THEN LOOK FOR DRIER WEATHER THROUGHOUT
THIS PERIOD. 33

&&

.AVIATION...WEAK UPPER LEVEL TROUGH WILL REMAIN OVER WESTERN WA
TODAY WITH LIGHT SOUTHWESTERLY FLOW ALOFT AND LIGHT LOW LEVEL FLOW AS
WELL. AIR MASS MOIST AND SLIGHTLY UNSTABLE.

CIGS EXPECTED TO BE MAINLY WITHIN VFR...RANGING FROM 4 KFT TO 6 KFT.
THE EXCEPTION BEING NEAR SHOWERS...WHERE CIGS WILL LOWER TO MVFR/IFR
RANGE...OR AROUND 1000 FT. WHILE SOME SCATTERING OUT OF CLOUD COVER
IS POSSIBLE TODAY...GIVEN THE AMOUNTS OF MOISTURE AROUND...ANY
CLEARING WILL LIKELY BE BRIEF.

KSEA...S WIND 4 TO 8 KNOTS TODAY. VFR CIGS EXPECTED...DROPPING TO
MVFR BRIEFLY DURING SHOWERS. FELTON/SMR

&&

.MARINE...LIGHT GRADIENTS TODAY AS A WEAK SURFACE LOW OVER THE
OFFSHORE WATERS MOVES SOUTHEAST AND DISSIPATES. LIGHT ONSHORE FLOW
DEVELOPING ON SUNDAY. THE NEXT ORGANIZED FRONT REACHES THE WATERS ON
MONDAY WITH SMALL CRAFT WINDS POSSIBLE OVER THE COASTAL WATERS.
ONSHORE FLOW PATTERN WILL RESUME FOR TUESDAY AND WEDNESDAY. FELTON

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...NONE.

&&

$$

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