896  
FXUS66 KSEW 230412  
AFDSEW  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SEATTLE WA  
912 PM PDT TUE APR 22 2025  
   
SHORT TERM /TONIGHT THROUGH THURSDAY/
 
CURRENT SATELLITE IMAGERY  
SHOWS FAIR WEATHER CUMULUS SHRINKING OVER THE OLYMPICS AND CASCADES,  
OTHERWISE, CLEAR SKIES OVER W WA THIS EVENING. A QUICK LOOK AT  
DEWPOINTS ACROSS THE AREA SHOWS THE POTENTIAL FOR ANOTHER ROUND OF  
OVERNIGHT LOWS DIPPING INTO THE 30S FOR MOST LOCATIONS.  
 
INHERITED FORECAST IS ON TRACK WITH NO NEED FOR ANY EVENING UPDATES.  
FOR ADDITIONAL FORECAST DETAILS, PLEASE REFER TO THE PREVIOUS  
DISCUSSION SECTION BELOW.  
 
18  
 
FROM PREVIOUS DISCUSSION...DRY AND MOSTLY SUNNY CONDITIONS DOMINATE  
ACROSS WESTERN WA THIS AFTERNOON AS A RIDGE OF HIGH PRESSURE NOSES  
INTO THE REGION. ANOTHER COOL NIGHT IS EXPECTED OVERNIGHT WITH AREAS  
OF ISOLATED FOG AND FROST POSSIBLE AGAIN. THAT SAID, TEMPERATURES  
ARE EXPECTED TO BE SLIGHTLY HIGHER, LIMITING THE FROST EXTENT EVEN  
MORE THAN THIS MORNING.  
 
THE RIDGE WILL SHIFT EAST ACROSS THE REGION WEDNESDAY AND THURSDAY  
ALLOWING FOR A SIGNIFICANT WARM UP. BY THURSDAY, AFTERNOON HIGHS  
WILL REACH INTO THE LOW TO MID 70S ACROSS THE REGION.  
   
LONG TERM /FRIDAY THROUGH TUESDAY/...FROM PREVIOUS DISCUSSION
 
BY  
FRIDAY, A TROUGH OFF THE COAST WILL ELONGATE AND CLUSTER ANALYSIS  
NOW SLIGHTLY FAVORS A CUTOFF LOW BRINGING THE BULK OF THE ENERGY  
SOUTH OF THE REGION FRIDAY THROUGH SUNDAY AND LEAVING WESTERN WA  
WARMER AND SOMEWHAT DRIER. STILL THERE IS A ~40% CHANCE THAT THE  
TROUGH HOLDS TOGETHER AND BRINGS MORE OF THE ENERGY OUR WAY LEADING  
TO A WETTER AND COOLER SOLUTION.  
 
THERE REMAINS A SIGNAL IN ENSEMBLE GUIDANCE FOR WEAK AND POTENTIALLY  
TRANSIENT RIDGING IN THE MONDAY/TUESDAY TIMEFRAME NEXT WEEK. ALL IN  
ALL, LITTLE IMPACT IS EXPECTED AT THIS TIME.  
-WOLCOTT-  
 

 
   
AVIATION
 
UPPER LEVEL RIDGE OFFSHORE MOVING INLAND WEDNESDAY  
EVENING. NORTHWESTERLY FLOW ALOFT WITH NORTHWESTERLY ONSHORE  
SURFACE GRADIENTS. MOSTLY CLEAR SKIES. PATCHY STRATUS WEDNESDAY  
MORNING WILL BE RESTRICTED TO OUTLYING RIVER VALLEYS, THE CHEHALIS  
GAP, AND PORTIONS OF THE IMMEDIATE COAST.  
 
KSEA...MOSTLY CLEAR SKIES. NORTH WIND 6 TO 10 KNOTS BECOMING  
NORTHEAST 4 TO 8 KNOTS AROUND 08Z. WINDS SWITCHING TO NORTHWEST 6  
TO 10 KNOTS AROUND 18Z. FELTON  
 

 
   
MARINE
 
A BROAD SURFACE RIDGE CENTERED OFFSHORE WILL GRADUALLY  
WEAKEN INTO THURSDAY. A WEAK TROUGH MOVING INTO THE OREGON OFFSHORE  
WATERS LATE IN THE WEEK WILL INCREASE NORTHWESTERLIES OVER THE  
COASTAL WATERS, BUT WILL OTHERWISE PRODUCE LITTLE IMPACT ACROSS AREA  
WATERS. 27  
 

 
   
HYDROLOGY
 
NO RIVER FLOODING IS EXPECTED OVER THE NEXT 7 DAYS.  
 

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

 
 

 
 
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