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AREA FORECAST DISCUSSION 
NATIONAL WEATHER SERVICE SEATTLE WA
300 PM PST MON MAR 2 2015

.SYNOPSIS...AN UPPER RIDGE AND LOW LEVEL OFFSHORE FLOW WILL GIVE 
MOSTLY CLEAR WEATHER TO WESTERN WASHINGTON THROUGH MIDWEEK. A  
WEATHER SYSTEM MOVING INTO BRITISH COLUMBIA THURSDAY WILL WEAKEN THE 
RIDGE. HIGH PRESSURE WILL BUILD AGAIN FOR THE WEEKEND.

&&

.SHORT TERM...COLD DRY AIR AND A HIGH OVER ALBERTA IS SENDING SOME 
COOL DRY AIR INTO WESTERN WA AS WELL. THE NEXT TWO NIGHTS OUGHT TO 
BE FROSTY IN THE NORMALLY COLDER WIND SHELTERED SPOTS. AN UPPER 
RIDGE IS JUST OFFSHORE WITH NLY FLOW ALOFT OVER WA. THE RIDGE WILL 
WEAKEN AFTER THE MIDDLE OF THE WEEK AS A SYSTEM MOVES INTO 
B.C...JUST BRUSHING THE NORTH PART OF WRN WA. IT WILL BE A LITTLE ON 
THE COOL SIDE AT FIRST...BUT LOOKING AT THE 850MB TEMPS FROM THE 
LATEST GFS SHOWS A WARMING TREND FROM AROUND -3C TUESDAY MORNING TO 
AROUND +6C LATE IN THE WEEK.

.LONG TERM...AFTER THE RIDGE WEAKENS THURSDAY UPPER HEIGHTS REBOUND 
FOR THE WEEKEND AND A WARMING TREND WILL LIKELY RESUME. THE FORECAST 
WAS ADJUSTED TO LIMIT THE CHANCE OF PRECIP THU AND FRI TO JUST THE 
NORTH CASCADES...MOST MODELS ARE DRY OVER ALL OF WRN WA ALL WEEK. 
TEMPS WERE ALSO WARMED UP A BIT IN THE EXTENDED FORECAST.

&&

.HYDROLOGY...FLOODING IS UNLIKELY FOR THE NEXT 7 DAYS.

&&

.AVIATION...AN UPPER RIDGE WILL REMAIN CENTERED OFFSHORE. STRONG NLY 
FLOW ALOFT WILL WEAKEN DURING THE DAY TUE. MODERATELY STRONG LOW 
LEVEL NLY FLOW WILL BECOME ELY TONIGHT. VFR CONDITIONS ARE 
ANTICIPATED BUT THERE MIGHT BE PATCHY SHALLOW FOG REDUCING VSBYS 
INTO 3-5SM RANGE AFTER 1000 UTC FROM ABOUT KOLM SWD AND WWD.

KSEA...VFR CONDITIONS ARE ANTICIPATED THRU TUE MORNING. WIND WILL
BE NLY 10-15 KT /WITH OCNL GUSTS NEAR 20 KT THIS AFTERNOON/. WINDS
WILL GRADUALLY DIMINISH TONIGHT.

&&

.MARINE...
A 1039 MB HIGH OVER WESTERN CANADA WILL WEAKEN TONIGHT. LOOK FOR
A 1037 MB HIGH TO ALSO DEVELOP OVER MONTANA LATE TONIGHT. THIS
COMBINED WITH LOWER PRES OVER OREGON AND THE COASTAL WATERS WILL
CAUSE THE NORTHERLY FLOW TO BECOME EASTERLY OR OFFSHORE EARLY TUE.
THE OFFSHORE FLOW WILL WEAKEN DURING THE DAY TUE...WITH THE FLOW
BECOMING FLAT BY TUE NIGHT.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORIES ARE IN EFFECT FOR ALL WATERS.

&&

$$

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