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000
FXUS66 KSEW 292245
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
300 PM PST THU JAN 29 2015

.SYNOPSIS...AN UPPER RIDGE WILL PROVIDE DRY AND MILD WEATHER THROUGH
SATURDAY. A FRONT WILL BRING RAIN BACK TO THE AREA SUNDAY AND EARLY
NEXT WEEK.

&&

.SHORT TERM...AN UPPER LEVEL RIDGE OVER THE PAC NW WILL LEAD TO DRY
AND MILD WEATHER ACROSS WESTERN WA THROUGH SATURDAY. EXPECT PATCHY
FOG OVERNIGHT WITH MOSTLY SUNNY SKIES ON FRIDAY. HIGH TEMPERATURES
WILL BE ABOVE NORMAL WITH HIGHS IN THE 50S. A WARM FRONT WILL MOVE
INTO B.C. ON SATURDAY WHICH MAY CLIP THE AREA FOR A FEW MORE CLOUDS.
BUT WE COULD SEE HIGHS IN THE LOW 60S SATURDAY AFTERNOON. RAIN AND
SLIGHTLY COOLER WEATHER WILL RETURN ON SUNDAY AS A COLD FRONT MOVES
INLAND.

.LONG TERM...ANOTHER PACIFIC FRONTAL SYSTEM WILL BRING A ROUND OF
WET WEATHER TO WESTERN WASHINGTON ON MONDAY. SNOW LEVELS WILL BE
LOWER...AROUND 4000 FEET...WITH A FEW INCHES OF SNOW IN THE
MOUNTAINS. MODELS TRY TO BRING A WEAK UPPER LEVEL RIDGE TO THE
REGION ON TUE FOR DRIER WEATHER. THE RIDGE MAY FLATTEN/WEAKEN BY
MIDWEEK AS MORE MOISTER ROLLS THROUGH THE PAC NW. 33

&&

.HYDROLOGY...FLOODING IS NOT EXPECTED FOR THE NEXT 7 DAYS.

&&

.AVIATION...A WEAK UPPER LEVEL RIDGE WILL REMAIN OVER WESTERN
WASHINGTON TONIGHT AND FRIDAY. AT THE SURFACE NORTHERLY AND OFFSHORE
FLOW WILL CONTINUE. SATELLITE IMAGERY SHOWS VIRTUALLY CLEAR SKIES
THIS AFTERNOON BUT PATCHY FOG/STRATUS IS LIKELY LATE TONIGHT AND
FRIDAY MORNING OVER THE SOUTHWEST INTERIOR AND POSSIBLY OTHER AREAS.

KSEA...VFR WILL BE THE MAIN CONDITIONS THROUGH FRIDAY. STRATUS/FOG
MAY REACH AS FAR NORTH AS THE TERMINAL FRIDAY MORNING AND FOR NOW
WILL HANDLE THAT WITH 2SM BR SCT003 FOR A FEW HOURS. NORTHERLY WIND
4-8 KT. CHB

&&

.MARINE...A SURFACE RIDGE CENTERED OVER EASTERN WASHINGTON WILL
MAINTAIN WEAK OFFSHORE FLOW THROUGH SATURDAY. PRESSURE GRADIENTS
ACROSS WESTERN WASHINGTON WILL REMAIN WEAK...PRODUCING NORTHEAST
WINDS ALONG THE COAST AND THROUGH PUGET SOUND...AND EASTERLY WINDS
THROUGH THE STRAIT. WINDS ARE FORECAST TO REMAIN LESS THAN 20 KT
EXCEPT FOR THE WEST ENTRANCE WHERE A SMALL CRAFT ADVISORY FOR 15-25
KT WINDS IS IN EFFECT THIS EVENING. WINDS COULD REACH ADVISORY LEVEL
THERE FROM TIME TO TIME THROUGH SATURDAY.

MODELS BRING A FRONT ACROSS THE AREA SUNDAY. MODELS HAVE BEEN
WAFFLING BUT THE LATEST GFS RUN INDICATES SOUTHERLY WINDS OF 15-25
KT ON THE COAST WITH 10-20 KT INLAND. ANOTHER FRONT MONDAY COULD BE
A BIT STRONGER. A NEW IDEA IN THE GFS IS A NORTHEASTERLY OUTFLOW
EVENT ON TUESDAY WHICH COULD BRING ADVISORY LEVEL WINDS TO INLAND
ZONES SUCH AS THE NORTH INTERIOR. CHB

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY WEST ENTRANCE.

&&

$$

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