Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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000
FXUS66 KSEW 132316
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
330 PM PST THU NOV 13 2014

.SYNOPSIS...A WEATHER SYSTEM WILL BRUSH THE FAR SOUTH PART OF THE
AREA THIS EVENING. DRY NORTHERLY FLOW ALOFT WITH LOW LEVEL OFFSHORE
WILL PREVAIL FRIDAY THROUGH EARLY NEXT WEEK. CLEAR SKIES AND BELOW
NORMAL TEMPERATURES ARE FORECAST THROUGHOUT THE PERIOD.

&&

.SHORT TERM...AN OCCLUDED SURFACE FRONT CONTINUES TO SPREAD MOISTURE
TO NORTHWEST OREGON AND SOUTHWEST WA THIS AFTERNOON. THE BULK OF THE
MOISTURE WILL REMAIN SOUTH OF THE CWA WHERE THERE IS A WINTRY
MIX. THE FINER SCALE MODELS LIKE THE HRRR AND UW WRF GFS SHOW THE
PRECIP BAND SHIFTING FARTHER SOUTH THIS EVENING...WITH LIGHT PRECIP
ENDING ACROSS THE FAR SOUTHERN EDGE OF THE CWA. THIS SYSTEM DID
SPREAD MID LEVEL CLOUDS UP TO KING COUNTY BUT IT WILL STILL REMAIN
DRY TONIGHT. AREAS NORTH OF SEATTLE ARE CLEAR. DEW POINTS ARE IN THE
SINGLE DIGITS TO TEENS AND LOWS OVERNIGHT WILL ONCE AGAIN DROP INTO
THE 20S TO LOWER 30S...WITH A FEW TEENS POSSIBLE.

DRY NORTHERLY FLOW WILL PREVAIL FRIDAY AND SATURDAY FOR CLEAR SKIES
AND BELOW NORMAL TEMPERATURES. MIN TEMPS WILL BE IN THE 20S TO LOWER
30S WITH HIGHS IN THE LOWER TO MID 40S. THE LOW LEVEL FLOW WILL
REMAIN OFFSHORE BUT STRONG EAST WINDS ARE NOT EXPECTED. ON SUNDAY AN
UPPER LEVEL RIDGE WILL SHIFT INLAND FOR MORE DRY AND STABLE WEATHER.
33

.LONG TERM...THE UPPER LEVEL RIDGE WILL REMAIN IN CONTROL OVER THE
WESTERN CONUS THROUGH AT LEAST MON. THIS MEANS MORE DRY AND COOL
WEATHER FOR WESTERN WA. THE RIDGE WILL THEN START TO BREAK DOWN TUE
OR WED AS AN UPPER TROUGH MOVES IN. THE 12Z 13KM GFS SHOWS LIGHT
RAIN REACHING WESTERN WA BY 00Z TUE WHICH IS FASTER THAN THE
OPERATIONAL RUN. THE 12Z ECMWF IS SLOWER WITH RAIN HOLDING OFF UNTIL
LATE TUE NIGHT. BUT BY WED IT LOOKS LIKE PRECIP WILL SPREAD ACROSS
THE ENTIRE REGION AS THIS TROUGH LIFTS THROUGH. TEMPS AND POPS WERE
NUDGED CLOSER TO CLIMO FOR NOW. 33

&&

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

&&

.AVIATION...BKN-OVC060 SOUTH OF KALALOCH-PWT-SEA-SNOQUALMIE PASS
THIS AFTN ASSOCIATED WITH EASTWARD-MOVING WEATHER DISTURBANCE DOWN
OVER OREGON. AS THE DISTURBANCE MOVES EAST THIS EVENING...THE CLOUDS
WILL DISSIPATE FROM LEWIS COUNTY ON NORTH. FURTHER NORTH OVER THE
REST OF WRN WA...A DRY AND STABLE AIR MASS WILL PERSIST FOR THE NEXT
24 HOURS AND BEYOND WITH LIGHT TO MODERATE NORTH WINDS ALOFT.
DRYNESS OF THE AIR MASS ELIMINATES ANY CONCERN FOR OVERNIGHT FOG
DEVELOPMENT...DESPITE CLEAR SKIES.

KSEA...OTHER THAN SCT060 THROUGH ABOUT 04Z...MAINLY LOOKING SOUTH
FROM THE TERMINAL...CLEAR SKIES ARE EXPECTED FOR THE NEXT 24 HOURS
AND BEYOND. EAST WINDS AT THE SURFACE WILL CONTINUE TO WEAKEN
THROUGH FRI...BUT A MORE NORTHERLY COMPONENT IS LIKELY TO DEVELOP
THIS EVNG.    HANER

&&

.MARINE...A 1009 MB LOW ALONG THE CENTRAL OREGON COAST WILL WEAKEN
AND FILL AS IT MOVES EAST ACROSS OREGON TONIGHT. HIGH PRESSURE OVER
THE INTERIOR OF BRITISH COLUMBIA WILL ALSO WEAKEN SLIGHTLY THROUGH
FRIDAY...THEN RE-STRENGTHEN A BIT ON SAT. OFFSHORE FLOW WILL
CONTINUE THROUGH AT LEAST TUE OF NEXT WEEK.    HANER

&&

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

PZ...SMALL CRAFT ADVISORY COAST...WEST ENTRANCE...CENTRAL STRAIT
      AND NORTHERN INLAND WATERS.

&&

$$

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