Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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000
FXUS66 KSEW 111556
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
856 AM PDT FRI JUL 11 2014

.SYNOPSIS...STRONG HIGH PRESSURE ALOFT WILL PREVAIL OVER THE
REGION THROUGH THIS WEEKEND FOR WELL ABOVE OR POSSIBLY RECORD
BREAKING TEMPERATURES. THE AIR MASS WILL ALSO BECOME MOIST
AND UNSTABLE ENOUGH FOR A RISK OF THUNDERSTORMS OVER THE
CASCADES THIS WEEKEND.

&&

.SHORT TERM...
THERE WERE AREAS OF STRATUS AND FOG ON THE COAST AND PARTS OF THE
SOUTHWEST INTERIOR AT THIS TIME. LOOK FOR THE CLOUDS/FOG TO BURN
OFF BY NOON...LEAVING THE ENTIRE CWA UNDER BRIGHT...SUNNY SKIES.

MEANWHILE...AN UPPER RIDGE WILL PREVAIL OVER THE REGION THROUGH
TONIGHT. THE SURFACE ONSHORE PRESSURE GRADIENT...ALBEIT VERY
WEAK...WILL BECOME FLAT TONIGHT. DAYTIME TEMPS TODAY WILL BE
ABOVE NORMAL.

THE UPPER RIDGE WILL CONTINUE TO BUILD SATURDAY AND SUNDAY...WITH
ITS AXIS JUST EAST OF THE CASCADES AND MOVING SLOWLY EASTWARD.
SATURDAY AND SUNDAY WILL BE HOT AND SUNNY ONCE AGAIN -- WITH THE
EXCEPTIONS NOTED BELOW -- AND AN EXCESSIVE HEAT WATCH IS IN EFFECT
FOR THE SEATTLE METRO AREA FOR THE WEEKEND. MARINE STRATUS SHOULD
DEVELOP ALONG THE COAST AT NIGHT...BUT BARELY PUSH INLAND AND BURN
OFF QUICKLY IN THE MORNINGS. SOUTHERLY FLOW ALOFT WILL RESULT IN
UPPER LEVEL INSTABILITY...AND AFTERNOON AND EVENING THUNDERSTORMS
COULD DEVELOP ALONG THE CASCADE CREST EITHER DAY.   MCDONNAL/05

.LONG TERM FROM THE PREV DISCUSSION...
THE PATTERN OF LIGHT ONSHORE FLOW WITH HEIGHTS NEAR 5900 METERS
WILL CONTINUE WELL INTO NEXT WEEK. HIGHS APPEAR LIKELY TO REMAIN
IN THE MID 80S TO LOWER 90S...WITH OVERNIGHT LOWS IN THE 60S...
THROUGH WEDNESDAY AT LEAST. SOMEWHAT STRONGER ONSHORE FLOW SHOULD
MEAN SLIGHTLY COOLER WEATHER ON THURSDAY...BUT AN ONSHORE PUSH
LOOKS UNLIKELY BEFORE FRIDAY. MCDONNAL

&&

.AVIATION...LIGHT FLOW ALOFT. THE AIR MASS IS DRY EXCEPT FOR MORNING
LOW CLOUDS ON THE COAST AND SOME FOG OR LOW CLOUDS OVER PORTIONS OF
SW WA.

KSEA...CLEAR SKIES AND AN AFTERNOON AND EVENING NLY BREEZE.

&&

.MARINE...HIGHER PRESSURE IS OFFSHORE WITH LOWER PRESSURE INLAND...
HOWEVER PRESSURE GRADIENTS ARE RELATIVELY LIGHT OVER THE AREA. THERE
SHOULD BE TYPICAL...ALTHOUGH FAIRLY WEAK...SUMMERTIME AFTERNOON NW
SEA BREEZES THROUGH THE WEEKEND AND INTO NEXT WEEK.

&&


.SEW WATCHES/WARNINGS/ADVISORIES...
WA...EXCESSIVE HEAT WATCH IN EFFECT FROM SATURDAY MORNING THROUGH
     SUNDAY EVENING FOR PARTS OF THE PUGET SOUND REGION

PZ...NONE.

&&

$$

WWW.WEATHER.GOV/SEATTLE

FOR THE GRAPHICAL AFD...VISIT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML




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