FXUS66 KSEW 242206
AFDSEW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
306 PM PDT FRI MAY 24 2013
.SYNOPSIS...A WEAKENING LOW PRESSURE SYSTEM WILL REMAIN OVER THE 
REGION THROUGH THIS WEEKEND BUT THERE WILL BE A TREND TOWARD LESS 
SHOWERS...MORE SUNSHINE...AND WARMER AFTERNOON TEMPERATURES. ANOTHER 
UPPER LOW WILL MAINLY IMPACT THE SOUTHWEST PART OF THE STATE ON 
MEMORIAL DAY.
&&
.SHORT TERM...
THERE WERE SCATTERED SHOWERS...MORE NUMEROUS OVER THE SOUTHWEST 
HALF...PRESENT OVER THE FORECAST AREA THIS AFTERNOON. MUCH OF THIS 
ACTIVITY WILL DISSIPATE THIS EVENING.
AN UPPER LOW WILL REMAIN OVER THE PACIFIC NORTHWEST THROUGH THIS 
WEEKEND BUT WILL GRADUALLY FILL AND WEAKEN WITH TIME. THIS WILL 
RESULT IN A TREND TOWARD LESS SHOWERS...MORE SUNSHINE...AND WARMER 
AFTERNOON TEMPERATURES.
THE UPPER TROF WILL MOVE EAST OF THE AREA LATE SUNDAY NIGHT OR EARLY 
MON. HOWEVER ANOTHER UPPER LOW IS EXPECTED TO DIG OFF THE COAST ON 
MEMORIAL DAY. THIS SYSTEM WILL HEAD TOWARD OREGON...THEREFORE THE 
BEST CHANCE OF PRECIP WILL LIKELY BE OVER THE SOUTHWEST PORTION OF 
THE CWA. WENT ON AHEAD AND REMOVED THE THREAT OF PRECIP FROM MUCH OF 
THE NORTHEAST HALF OF THE FORECAST AREA.  
.LONG TERM...
MUCH OF THIS PERIOD WILL BE UNSETTLED DUE TO A NEGATIVE TILTED UPPER 
TROF OVER THE REGION. THUS ANTICIPATE A RISK OF PRECIP...ESPECIALLY 
THE MIDDLE OF NEXT WEEK...AND GENERALLY BELOW NORMAL DAYTIME 
TEMPS.   
&&
.AVIATION...AN UPPER LEVEL TROUGH OVER WA WILL CONTINUE TO MIGRATE 
EASTWARD...ENTERING EASTERN WA BY THIS EVENING. SOUTHERLY FLOW 
CURRENTLY OVER WESTERN WA WILL CONTINUE INTO TOMORROW. MOIST AND 
SLIGHTLY UNSTABLE. SCATTERED SHOWERS...MOSTLY WEST OF THE 
SOUND...WILL DECREASE IN NUMBER BY TONIGHT. LESS THAN A 10 PERCENT 
CHANCE OF ISOLATED THUNDERSTORMS THIS AFTERNOON/EARLY EVENING.
KSEA...S WIND 5 TO 8 KT FOR NEXT 24 HOURS. MAINLY VFR CIGS 
EXPECTED...DROPPING TO MVFR DURING SHOWERS.
&&
.MARINE...LIGHTER GRADIENTS AND WINDS OVER MOST WA WATERS TODAY. 
WEAK ONSHORE FLOW WILL INCREASE A BIT TONIGHT THROUGH THE WEEKEND. 
EXPECTING SMALL CRAFT ADVISORY WINDS TO DEVELOP LATE THIS AFTERNOON 
IN THE CENTRAL AND EASTERN STRAIT...THUS AN ADVISORY IS IN PLACE.
THE NEXT ORGANIZED FRONT REACHES THE WATERS ON MONDAY WITH SMALL 
CRAFT WINDS PROBABLE OVER THE COASTAL WATERS. 
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 2 AM PDT SATURDAY FOR
     THE CENTRAL AND EASTERN STRAIT OF JUAN DE FUCA.
&&
$$
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