Area Forecast Discussion
Issued by NWS Seattle/Tacoma, WA

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000
FXUS66 KSEW 222316
AFDSEW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
315 PM PST SUN FEB 22 2015

.SYNOPSIS...AN UPPER RIDGE WILL KEEP THE WEATHER DRY TONIGHT AND
MONDAY. A WEAK UPPER TROUGH WILL BRING A RETURN TO ONSHORE FLOW ON
TUESDAY. MOIST NORTHWEST FLOW ALOFT WILL PREVAIL WEDNESDAY THROUGH
FRIDAY. DRIER NORTHERLY FLOW ALOFT WILL DEVELOP NEXT WEEKEND.

&&

.SHORT TERM...SKIES WILL BE MOSTLY CLEAR TONIGHT AND MONDAY WITH AN
UPPER RIDGE CENTERED JUST OFFSHORE. THE UPPER RIDGE WILL BREAK DOWN
ON TUESDAY WITH A SHORT WAVE COMING OVER THE TOP. THIS FEATURE LOOKS
DRY AND THE MAIN IMPACT WILL BE TO BRING A BIT MORE CLOUDS TO THE
AREA WITH THE ONSHORE FLOW.

IT LOOKS LIKE THERE WILL BE A BIT OF A MARINE PUSH TUESDAY NIGHT
WITH INCREASING CLOUDS. THERE WILL ALSO BE AN INCREASING CHANCE OF
RAIN FOR THE AREA TUESDAY NIGHT AND WEDNESDAY AS MOISTURE COMES IN
FROM THE NORTHWEST. SCHNEIDER

.LONG TERM...MOIST NORTHWEST FLOW ALOFT WILL PREVAIL WEDNESDAY NIGHT
THROUGH ABOUT FRIDAY. THIS PERIOD LOOKS RAINY AT TIMES AND POPS WERE
RAISED A BIT FOR MOST AREAS. TRYING TO TIME INDIVIDUAL UPPER SHORT
WAVES WHICH MIGHT ENHANCE THE RAIN CHANCES IS TRICKY THIS FAR OUT
AND THE FORECAST IS FAIRLY BROADBRUSH FOR NOW.

DRIER NORTHERLY FLOW ALOFT WILL DEVELOP FRIDAY NIGHT WITH SHOWERS
GENERALLY ENDING FROM NORTH TO SOUTH. THE WEEKEND LOOKS DRY WITH AN
UPPER RIDGE OVER THE NORTHEAST PACIFIC ALTHOUGH SOME RAIN MIGHT
REACH THE AREA LATE SUNDAY AS THE NEXT SYSTEM DROPS DOWN FROM THE
NORTHWEST SCHNEIDER

&&

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

&&

.AVIATION...A STRONG UPPER RIDGE OFF THE COAST WILL KEEP DRY
NORTHERLY FLOW OVER WASHINGTON THROUGH MON MORNING. THE RIDGE WILL
START TO WEAKEN ON MON AFTN...SO NORTHERLY FLOW WILL WEAKEN.
LIKEWISE...LOW-LEVEL OFFSHORE FLOW WILL WEAKEN ON MON AS WELL. THE
AIR MASS WILL BE DRY AND STABLE. AS A RESULT...FOG ON MON MORNING
WILL BE LIMITED TO THE MOST FOG-PRONE LOCATIONS SUCH AS OLYMPIA...
CHEHALIS AND THE SNOHOMISH VALLEY. ANY FOG ON MON MORNING WILL BE
SHALLOW.

KSEA...OTHER THAN A FEW THIN HIGH CLOUDS...CLEAR SKIES. N-NE
WINDS...EASING BELOW 6 KT ARND 04Z THIS EVNG. N-NE WINDS ON MON
GENERALLY REMAINING BELOW 6 KT. NO FOG AT KSEA MON MORNING.   HANER

&&

.MARINE...EASTERLY GRADIENTS WILL GRADUALLY WEAKEN TONIGHT. FAIRLY
FLAT GRADIENTS OVER THE WRN WA WATERS ON MON. ONSHORE FLOW WILL
RETURN ON TUESDAY AND SHOULD BECOME STRONG ENOUGH FOR SMALL CRAFT
ADVISORY WEST WINDS IN THE STRAIT TUESDAY NIGHT. WEAK ONSHORE FLOW
WILL CONTINUE WED AND THU. MODELS SHOWING STRENGTHENING NE GRADIENTS
NEXT FRI.   HANER

&&

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

&&

$$

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