378  
FXUS66 KSEW 080936  
AFDSEW  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SEATTLE WA  
236 AM PDT TUE JUL 8 2025  
   
SYNOPSIS
 
WARM AND DRY CONDITIONS WILL PERSIST TODAY UNDER HIGH  
PRESSURE. A WEAK SYSTEM WILL CROSS THE REGION ON WEDNESDAY,  
BRINGING LIGHT RAIN AND COOLER TEMPERATURES. HIGH PRESSURE WILL  
REBOUND TOWARDS THE END OF THE WEEK, BRINGING A RETURN OF WARMER  
AND DRY CONDITIONS BY FRIDAY AND INTO EARLY NEXT WEEK.  
 

 
   
SHORT TERM /TODAY THROUGH THURSDAY/
 
HIGH PRESSURE WILL REMAIN  
IN PLACE OVER THE WESTERN US TODAY, MAINTAINING WELL ABOVE  
NORMAL TEMPERATURES. HIGHS TODAY ARE ON TRACK TO PEAK IN THE MID  
TO UPPER 80S ACROSS THE INTERIOR, WARMEST ALONG THE CASCADE  
FOOTHILLS AND VALLEYS. THIS WILL BRING ANOTHER DAY OF MODERATE  
(ORANGE) HEATRISK TO MOST METRO AREAS SURROUNDING THE PUGET SOUND,  
WITH MINOR (YELLOW) HEATRISK ELSEWHERE. AREAS ALONG THE COAST  
WILL SEE FOG AND LOW STRATUS THIS MORNING, WITH INCREASING ONSHORE  
FLOW THROUGHOUT THE DAY MODERATING TEMPERATURES ALONG THE COAST  
INTO THE MID TO UPPER 60S. WHILE MOST INLAND AREAS WILL START THE  
DAY WITH CLEAR SKIES, ONSHORE FLOW WILL PICK UP BY THE AFTERNOON  
AND CLOUDY SKIES WILL FILL IN BY THE EVENING AS THE NEXT SYSTEM  
APPROACHES.  
 
AN APPROACHING DISTURBANCE WILL BRING A SIGNIFICANT COOL DOWN ON  
WEDNESDAY AS A STRONG PUSH OF MARINE AIR MOVES INTO THE REGION.  
LIGHT RAIN WILL SPREAD INLAND THROUGHOUT THE DAY WEDNESDAY, WITH  
THE BULK OF THE MOISTURE FOCUSED OVER THE CASCADES, WHERE  
GENERALLY UP TO HALF AN INCH OF RAIN IS POSSIBLE THROUGH THURSDAY  
MORNING. AREAS IN THE NORTH CASCADES MAY SEE LOCALLY HIGHER  
RAINFALL AMOUNTS CLOSER TO AN INCH. ELSEWHERE, LOWER ELEVATIONS  
WILL SEE LIGHT ACCUMULATIONS, GENERALLY RANGING FROM A FEW  
HUNDREDTHS TO A QUARTER OF AN INCH. THE MOIST MARINE AIR WILL COOL  
TEMPERATURES CONSIDERABLY, WITH HIGHS WEDNESDAY PEAKING IN THE  
MID TO UPPER 60S FOR MOST LOWLAND AREAS.  
 
CONDITIONS WILL DRY OUT BY THE LATE MORNING THURSDAY AS HIGH  
PRESSURE STARTS TO BUILD INLAND, WITH CLOUDY SKIES IN THE MORNING  
CLEARING BY THE AFTERNOON. TEMPERATURES WILL REBOUND SEVERAL  
DEGREES AND RETURN TO NEAR NORMAL, WITH MOST OF THE INTERIOR  
SEEING HIGHS IN THE LOW TO MID 70S.  
   
LONG TERM /FRIDAY THROUGH MONDAY/
 
ENSEMBLES REMAIN IN GOOD  
AGREEMENT OVER HIGH PRESSURE BUILDING INTO THE REGION OVER THE  
WEEKEND AND INTO EARLY NEXT WEEK. FRIDAY WILL BRING A RETURN OF  
WARM AND DRY CONDITIONS ACROSS WESTERN WASHINGTON, WITH WIDESPREAD  
AREAS OF MINOR (YELLOW) HEATRISK ACROSS THE LOWLANDS AND HIGHS  
RETURNING INTO THE 80S EAST AND SOUTH OF THE PUGET SOUND.  
TEMPERATURES WILL CONTINUE TO WARM UP THROUGH THE WEEKEND AS A  
RIDGE OFFSHORE AMPLIFIES. THIS WILL GIVE ANOTHER POTENTIAL  
PERIOD OF INCREASED HEATRISK AS WELL AS AN INCREASE IN FIRE  
WEATHER CONCERNS OVER THE WEEKEND AND INTO THE START OF NEXT  
WEEK.  
 
15  
 

 
   
AVIATION
 
A RIDGE WILL BEGIN TO SLIDE EASTWARD THIS MORNING WITH A  
LOW/TROUGH TO THE WEST, BEGINNING TO TRANSITION THE ZONAL FLOW  
PATTERN ALOFT TO SOUTHWESTERLY TODAY. INTERIOR TERMINALS ARE  
REPORTING VFR WITH VARIABLE NORTH OR SOUTH WINDS THROUGHOUT PUGET  
SOUND AT AROUND OR LESS THAN 5 KT. THE WINDS ARE WESTERLY ALONG THE  
WATERWAYS (KHQM AND KCLM, WITH POTENTIAL FOR GUSTY WINDS JUST  
OFFSHORE MAKING THEIR WAY TO THE TERMINAL THIS MORNING). THE MARINE  
STRATUS IS EXPECTED TO REMAIN CONFINED TO THE PACIFIC COAST THIS  
MORNING, WITH CEILINGS DROPPING TO IFR/LIFR AND POTENTIAL FOR  
VISIBILITIES TO ALSO DROP IN THESE CATEGORIES. THE ONGOING PUSH  
THROUGH THE STRAIT OF JUAN DE FUCA MAY ALSO PUSH LOWER CIGS TO SOME  
NEARBY ADJACENT TERMINALS (BETWEEN KBLI AND KAWO).  
 
THE REMAINDER OF TODAY STAYS DRY WITH HIGH CLOUDS (MARINE STRATUS  
WILL LINGER THE LONGEST ALONG THE COAST WITH ONLY A BRIEF BREAK TO  
MVFR/VFR EXPECTED THIS AFTERNOON). THE NEXT DISTURBANCE  
TONIGHT/WEDNESDAY MORNING WILL BRING SHOWERS ACROSS ALL TERMINALS,  
WITH CEILINGS LOWERING TO MVFR AND WIDESPREAD POCKETS OF IFR  
WEDNESDAY MORNING. SOUTHWEST FLOW ALOFT WILL TRANSLATE DOWN TO THE  
SURFACE LATER THIS MORNING, WITH WINDS RANGING 8-12 KT (COUPLE GUSTS  
TO 20 KT POSSIBLE). ANOTHER PUSH THROUGH THE STRAIT OF JUAN DE FUCA  
MAY CAUSE SOME DIFFLUENCE AND TURN WINDS NORTHERLY DOWN TO KBFI.  
 
KSEA...VFR CONDITIONS EXPECTED ALL OF TUESDAY, WITH A 70% CHANCE OF  
MVFR (20% CHANCE OF IFR) WEDNESDAY MORNING - GENERALLY AFTER 12Z.  
CLEAR SKIES TODAY WITH INCREASING CLOUD COVERAGE LATER TODAY WITH  
SHOWERS LIKELY AFTER 12Z WEDNESDAY. NORTH WINDS EARLY THIS MORNING  
AT 8 KT WILL BECOME LIGHT AND VARIABLE UNDER 5 KT THROUGH 18Z, THEN  
PICK UP OUT OF THE WEST/SOUTHWEST 8-12 KT, WITH A COUPLE GUSTS TO 18  
KT POSSIBLE). THE NORTHWESTERLY WINDS ARE EXPECTED AT THIS TIME TO  
HOLD TO THE NORTH OF KSEA (DOWN TO KBFI).  
 
HPR  
 

 
   
MARINE
 
THIS MORNING: CURRENTLY HAVE GUSTY WINDS CONTINUING IN  
PORTIONS OF THE EAST/CENTRAL STRAIT OF JUAN DE FUCA UP TO 25 KT.  
HAVE CONTINUED THE SMALL CRAFT ADVISORY THROUGH 9 AM LOCAL TIME.  
MUCH OF COASTAL WATERS AND THE STRAIT OF JUAN DE FUCA HAVE MARINE  
STRATUS AND/OR FOG COVERING MUCH OF THESE WATERS, WHICH MAY LIMIT  
VISIBILITIES AT TIMES THROUGH THIS MORNING.  
 
A TROUGH OVER THE COASTAL WATERS WILL BRING A WEAK FRONTAL SYSTEM  
ACROSS THE COASTAL WATERS TUESDAY NIGHT INTO WEDNESDAY WITH SHOWERS.  
THERE IS A SMALL POSSIBILITY THAT SEAS COULD BRIEFLY UPTICK. PUSHES  
THROUGH THE STRAIT OF JUAN DE FUCA WILL CONTINUE THROUGH MUCH OF THE  
WEEK, WITH ANOTHER STRONG PUSH LIKELY AGAIN TUESDAY  
AFTERNOON/EVENING. OPTED TO ISSUE ANOTHER SMALL CRAFT ADVISORY FOR  
THE EAST/CENTRAL STRAIT OF JUAN DE FUCA ZONES (ESPECIALLY WITH THE  
FRONT MOVING THROUGH AND INCREASING ONSHORE FLOW). ANOTHER WEAK LOW  
MAY PASS THE WATERS THURSDAY. HIGH PRESSURE WILL BUILD OFFSHORE  
FRIDAY INTO THE WEEKEND.  
 
SEAS ARE EXPECTED TO HOLD BETWEEN 3-6 FT THROUGH MUCH OF THE WEEK  
AND COULD BECOME STEEP AT TIMES WITH PERSISTENT NORTHERLY WINDS OVER  
THE COASTAL WATERS.  
 
HPR  
 

 
   
FIRE WEATHER
 
DRY, WARM WEATHER WILL LEAD TO ELEVATED FIRE WEATHER  
CONDITIONS CONTINUING THROUGH TUESDAY WITH HIGH PRESSURE SITUATED  
ACROSS WESTERN WASHINGTON. DESPITE LOW LEVEL ONSHORE FLOW BRINGING  
GOOD RH RECOVERIES OVERNIGHT, CONDITIONS WILL DRY OUT THIS  
AFTERNOON WITH MINIMUM RH VALUES DROPPING TOWARDS 25% TO 35% OVER  
THE MOUNTAINS AND THROUGH THE CASCADE FOOTHILLS AND VALLEYS.  
 
A WEAK FRONTAL SYSTEM WILL MOVE ACROSS WESTERN WASHINGTON ON  
WEDNESDAY. THIS WILL INCREASE ONSHORE FLOW, WITH MUCH COOLER  
TEMPERATURES AND INCOMING PRECIPITATION FOR SOME AREAS TUESDAY  
NIGHT THROUGH WEDNESDAY. THERE REMAINS A MODERATE (50% TO 70%)  
CHANCE OF WETTING RAIN FOR THE CASCADES OF SNOHOMISH COUNTY  
NORTHWARDS, WITH LIGHTER RAINFALL AMOUNTS ELSEWHERE.  
 
UPPER RIDGING WILL THEN BUILD BACK INTO WESTERN WASHINGTON LATE  
THURSDAY AND CONTINUE INTO NEXT WEEKEND, RESULTING IN THE RETURN  
OF WARM, DRY WEATHER AND ELEVATED FIRE WEATHER CONDITIONS. FRIDAY  
WILL BE THE DRIEST DAY OF THE PERIOD, WITH RH VALUES DROPPING INTO  
THE 25% TO 35% RANGE OVER THE MOUNTAINS AND ACROSS THE LOWLANDS  
SOUTH OF THE PUGET SOUND.  
 
15  
 

 
   
SEW WATCHES/WARNINGS/ADVISORIES
 
 
WA...NONE.  
PZ...SMALL CRAFT ADVISORY UNTIL 9 AM PDT THIS MORNING FOR CENTRAL  
U.S. WATERS STRAIT OF JUAN DE FUCA-EAST ENTRANCE U.S.  
WATERS STRAIT OF JUAN DE FUCA.  
 
SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 10 PM PDT THIS  
EVENING FOR CENTRAL U.S. WATERS STRAIT OF JUAN DE FUCA-EAST  
ENTRANCE U.S. WATERS STRAIT OF JUAN DE FUCA.  
 

 
 

 
 
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