Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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000
FXUS66 KSEW 281630
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
930 AM PDT MON JUL 28 2014

.SYNOPSIS...HIGH PRESSURE ALOFT WILL REMAIN OVER THE REGION
THROUGH THIS WEEKEND.

&&

.SHORT TERM...
NO CHANGES TO THE PREVIOUS THINKING BELOW.

UPPER LEVEL RIDGE CENTERED OVER THE ROCKIES SHOWING NO SIGNS OF
WEAKENING OR MOVING TODAY. 500 MB HEIGHTS WILL REMAIN IN THE MID
TO UPPER 580 DAM. MODEL 850 MB TEMPERATURES WILL WARM UP A DEGREE
OR TWO C FROM YESTERDAY TO PLUS 16 TO 19 C. AT THE SURFACE...THE
LIGHT ONSHORE FLOW PATTERN REMAINED INTACT. WITH THE SLIGHT
WARMING ALOFT...EXPECT HIGH TEMPERATURES OVER THE INTERIOR TO WARM
A COUPLE OF DEGREES TODAY. ALONG THE COAST AND STRAIT... WHERE THE
LIGHT ONSHORE FLOW WILL PROVIDE AN AFTERNOON SEA BREEZE...HIGHS
WILL REMAIN IN THE 70S.

NO CHANGE IN THE PATTERN BOTH AT THE SURFACE AND ALOFT ON TUESDAY.
TEMPERATURES ALOFT WILL BE SIMILAR TO READINGS OF TODAY. WILL GO
WITH A PERSISTENCE FORECAST ON TUESDAY.

A SMALL CHANGE WILL BE IN THE OFFING FOR WEDNESDAY. THE UPPER
LEVEL RIDGE WILL REMAIN OVER THE AREA WITH THE 500 MB HEIGHTS
WEAKENING A TOUCH. LOW LEVEL ONSHORE GRADIENTS WILL ALSO PICK UP
A TOUCH. BOTH THESE CHANGES ARE MINOR AND IT CERTAINLY DOES NOT
LOOK LIKE A FULL BLOWN MARINE PUSH BUT WITH THE SMALL CHANGES
EXPECT LOW CLOUDS AND FOG TO SPREAD A LITTLE INLAND WEDNESDAY
MORNING. AFTERNOON HIGHS WILL BE A COUPLE OF DEGREES COOLER OVER
THE INTERIOR WITH A LITTLE MORE COOLING ALONG THE COAST.

.LONG TERM FROM THE PREV DISCUSSION...
EXTENDED MODELS IN GOOD AGREEMENT WITH LITTLE CHANGE IN THE
PATTERN...BOTH SURFACE AND ALOFT...THROUGH THE WEEKEND. MODEL 500
MB HEIGHTS REMAIN IN THE MID 580 DAM WITH LIGHT ONSHORE FLOW AT
THE SURFACE. FLOW ALOFT WILL REMAIN SOUTHWESTERLY WHICH WILL PUSH
ANY CONVECTION THAT DEVELOPS OVER THE OREGON CASCADES EAST OF THE
NORTHERN AND CENTRAL WASHINGTON CASCADES. WITH THE PATTERN
REMAINING INTACT FOR OVER A WEEK IN A HALF...WILL HAVE TO START
THINKING ABOUT A MARINE PUSH AT SOME POINT LATE IN THE PERIOD OR
EARLY NEXT WEEK BUT RIGHT NOW NEITHER THE GFS OR THE ECMWF
INDICATED ANYTHING EXCEPT SHALLOW MARINE PUSHES. END RESULT...A
CONTINUATION OF THE CURRENT WEATHER WITH HIGHS A FEW DEGREES
ABOVE NORMAL FOR MOST OF THE AREA AND PLENTY OF SUNSHINE. FELTON

&&

.AVIATION...AN UPPER LEVEL RIDGE CENTERED OVER THE SOUTHWESTERN US
WILL PERSIST BEYOND TUESDAY GIVING SOUTHWEST FLOW ALOFT TO THE AREA.
AT THE SURFACE...HIGH PRESSURE OVER THE OFFSHORE WATERS AND LOW
PRESSURE EAST OF THE CASCADES WILL GIVE LIGHT ONSHORE FLOW TO THE
AREA. WHILE SOME FOG AND STRATUS OVER THE COASTAL WATERS WILL WORK
IN THROUGH THE STRAIT OF JUAN DE FUCA AND ONTO THE COASTAL ZONES
DURING THE LATE NIGHT AND MORNING HOURS...THE AIR MASS OVER THE
INLAND AREAS WILL BE DRY AND STABLE RESULTING IN GOOD VFR
CONDITIONS. STRATUS AND FOG OVER THE COASTAL AREAS WILL PULL BACK
INTO THE WATERS OF THE PACIFIC DURING THE AFTERNOON AND EARLY
EVENING HOURS. ALBRECHT

KSEA...CLEAR SKIES AND VFR CONDITIONS WILL PERSIST THROUGH TUESDAY.
EXPECT NORTHWEST WINDS 8-12 KNOTS THIS AFTERNOON AND EVENING TO TURN
NORTHEASTERLY 4-7 KNOTS AFTER 05Z THIS EVENING. ALBRECHT

&&

.MARINE...HIGH PRESSURE OVER THE OFFSHORE WATERS AND LOWER PRESSURE
EAST OF THE CASCADES WILL PERSIST FOR THE NEXT SEVERAL DAYS. THIS
PATTERN WILL RESULT IN VARYING DEGREES OF ONSHORE FLOW FOR THE NEXT
WEEK OR SO. STRONGEST WINDS WILL OCCUR THROUGH THE CENTRAL AND EAST
STRAIT...LIKELY REACHING SMALL CRAFT ADVISORY LEVELS DURING THE LATE
AFTERNOON AND EVENING HOURS. IN ADDITION...MODERATE NORTHWESTERLY
WINDS OVER THE COASTAL WATERS WILL PERSIST THROUGH MUCH OF THE
WEEK...NEAR OR JUST ABOVE SCA LEVELS AT TIMES DURING THE AFTERNOON
AND EVENING HOURS. AREAS OF LATE NIGHT AND MORNING FOG CAN BE
EXPECTED OVER THE COASTAL WATERS AND THROUGH THE STRAIT OF JUAN DE
FUCA EACH DAY. ALBRECHT

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY IN EFFECT FOR THE COASTAL WATERS AND
     CENTRAL/EASTERN STRAIT OF JUAN DE FUCA.


&&

$$

WWW.WEATHER.GOV/SEATTLE

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




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