504
FXUS66 KSEW 071000
AFDSEW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
300 AM PDT THU AUG 7 2025
SYNOPSIS
COOLER AND CLOUDIER CONDITIONS WILL CONTINUE TODAY,
WITH SHOWERS GRADUALLY TAPERING. A WARMING AND DRYING TREND
COMMENCES ON FRIDAY AND WILL PERSIST INTO EARLY NEXT WEEK AS
RIDGING OVER THE NORTHEASTERN PACIFIC BUILDS INTO THE REGION.
TEMPERATURES MAY MODERATE AGAIN BY MIDWEEK AS AN UPPER LEVEL LOW
SLIDES DOWN ALONG BRITISH COLUMBIA AND UPPER LEVEL TROUGHING
REDEVELOPS OVER THE AREA.
SHORT TERM /TODAY THROUGH SATURDAY/
RADAR THIS MORNING SHOWS
SHOWER ACTIVITY PERSISTING ACROSS THE NORTH AND CENTRAL SOUND.
EXPECT THIS ACTIVITY TO CONTINUE OVER THE NEXT SEVERAL HOURS,
BEFORE TAPERING THROUGHOUT THE DAY TODAY. OVERALL, GENERALLY
COOLER AND CLOUDIER CONDITIONS ARE EXPECTED THIS MORNING AS AN
UPPER LEVEL LOW SWINGS ACROSS THE AREA. SUN WILL BE LIKELY BY THE
AFTERNOON HOURS AS SHOWERS DISSIPATE. AFTERNOON HIGHS WILL BE IN
THE 60S ALONG THE COAST AND IN THE UPPER 60S TO MID 70S ACROSS THE
INTERIOR.
CONDITIONS START TO DRY OUT AND WARM UP ON FRIDAY AS RIDGING FROM
THE NORTHEASTERN PACIFIC STARTS TO BUILD INTO THE AREA. ONSHORE
FLOW WILL CONTINUE IN THE LOW LEVELS FOR AREAS OF MORNING STRATUS
THAT WILL SCATTER FOR SOME AFTERNOON SUN. HIGH TEMPERATURES WILL
CLIMB A FEW DEGREES FROM TODAY AND LOOK TO TOP OUT IN THE MID TO
UPPER 60S FOR THE COAST AND IN THE 70S TO NEAR 80 ACROSS THE
INTERIOR.
RIDGING WILL CONTINUE TO BUILD OVER THE AREA OVER THE WEEKEND,
ALLOWING FOR TEMPERATURES TO STEADILY WARM UP ACROSS WESTERN
WASHINGTON. AFTERNOON HIGHS ON SATURDAY WILL LARGELY BE IN THE
UPPER 60S TO LOW 70S ALONG THE COAST AND IN THE 70S TO LOW 80S
ACROSS THE INTERIOR. WITH MORNING LOWS PRIMARILY IN THE LOW TO MID
50S ACROSS THE AREA, HEATRISK WILL LARGELY BE IN THE MINOR
(YELLOW) CATEGORY FOR THE MAJORITY OF THE REGION.
LONG TERM /SUNDAY THROUGH WEDNESDAY/
TEMPERATURES ON SUNDAY
WILL CONTINUE TO WARM, WITH MORNING LOWS EXPECTED TO BE IN THE MID
TO UPPER 50S ACROSS THE AREA AND AFTERNOON HIGHS IN THE MID 70S
ALONG THE COAST AND IN THE 80S ACROSS THE INTERIOR. POCKETS OF
MODERATE (ORANGE) HEATRISK ARE LIKELY ON SUNDAY AS A RESULT,
MAINLY FOR AREAS SOUTH AND SOUTHWEST OF THE SOUND. THERE IS STILL
A DECENT SPREAD IN TEMPERATURES HEADING INTO EARLY NEXT WEEK,
HOWEVER MONDAY STILL LOOKS TO BE THE WARMEST DAY AT THIS TIME.
WITH MORNING LOWS IN THE UPPER 50S TO LOW 60S AND AFTERNOON HIGHS
IN THE 80S TO NEAR 90 ACROSS THE INTERIOR, MORE WIDESPREAD
MODERATE HEATRISK WILL BE PREVALENT ACROSS THE AREA.
ENSEMBLES CONTINUE TO SUGGEST A FLATTENING OF THE RIDGE ON
TUESDAY AND HINT AT TROUGHING REDEVELOPING OVER THE REGION BY
MIDWEEK AS A SYSTEM SLIDES DOWN ALONG BRITISH COLUMBIA. SHOULD
THIS COME TO FRUITION, THIS WOULD ALLOW FOR TEMPERATURES TO COOL A
FEW DEGREES BOTH DAYS. WHILE POCKETS OF MODERATE HEATRISK MAY
STILL BE POSSIBLE ACROSS PORTIONS OF THE INTERIOR ON TUESDAY,
EXPECT THE MAJORITY OF THE AREA TO LARGELY FALL BACK INTO THE
MINOR HEATRISK CATEGORY BY WEDNESDAY.
14
AVIATION
NORTHERLY FLOW IN THE WAKE OF AN EXITING UPPER LEVEL LOW
SHOULD BE IN PLACE BY LATE MORNING AND CONTINUE INTO TONIGHT BEFORE
SHIFTING MORE NORTHWESTERLY BY FRIDAY MORNING. A WIDE SAMPLING OF
BOTH WIND DIRECTIONS AND SPEEDS AT THE SURFACE. ALTHOUGH MANY
CONTINUE TO SEE SOUTHERLY WINDS, PAE AND HQM SHOW NORTHERLY INSTEAD
WHILE CLM, AS EXPECTED WITH DIURNAL WESTERLY PUSHES, IS WESTERLY.
SPEEDS ARE MOSTLY 4-8 KTS WITH THE EXCEPTION OF SEA, WHERE SPEEDS
HAVE SAT MORE IN THE 8-12 KTS RANGE FOR MUCH OF THE EARLY MORNING.
THIS SHOULD START TO EASE BETWEEN 10-12Z. THE OVERALL PATTERN
EXPECTED TO EMERGE THIS AFTERNOON WILL BE NORTHERLY WINDS WITH
SPEEDS GENERALLY 4-8 KTS.
CIGS ALSO A MIXED BAG OUT THERE THIS MORNING. MAJORITY OF TERMINALS
ARE VFR AT THE TIME OF THIS WRITING /09Z/ WITH A COUPLE OF ISOLATED
IFR OBS AND SOME MVFR LOCATIONS NEAR SHOWER ACTIVITY OVER THE
EASTERN HALF OF THE CWA. LOW-LEVEL MOISTURE SHOULD BRING WIDESPREAD
MVFR CONDITIONS BY AROUND 12Z AND THESE ARE PROGGED TO HANG ON INTO
THE EARLY AFTERNOON BEFORE LIFTING AND SCATTERING OUT. HOWEVER,
GIVEN THE PROPENSITY OF CIGS TO SHIFT UP AND DOWN THROUGHOUT THIS
ENTIRE EPISODE, CONFIDENCE REMAINS LOW AND IT MERITS MENTIONING THAT
CONDITIONS SHOULD BE MONITORED AS AMENDMENTS MAY BE NEEDED...BUT AT
THIS TIME, WILL STICK WITH INHERITED FORECAST AS EXPERIENCE TENDS TO
LEAN TOWARD POST FRONTAL LOW-LEVEL MOISTURE WINNING OUT IN THE END.
WIDESPREAD VFR CONDITIONS EXPECTED THIS AFTERNOON AND INTO TONIGHT
AS AN UPPER LEVEL RIDGE STARTS TO INFLUENCE THE AREA.
KSEA...VFR CONDITIONS STILL IN PLACE THIS EARLY MORNING BUT SUSPECT
THAT CIGS SHOULD SINK DOWN INTO MVFR AROUND 12Z AND REMAIN THERE
INTO THE LATE MORNING. GIVEN THE QUANDARY REGARDING CIGS MENTIONED
ABOVE, NOT SURE IF CURRENT FORECAST WENT PERHAPS A LITTLE TOO LOW,
AND WILL MONITOR TO MAKE ADJUSTMENTS /IF NEEDED/ IN THE 12Z
ISSUANCE. BUT GENERAL TREND AS DISPLAYED IN CURRENT FORECAST LOOKS
GOOD. HIGHER WIND SPEEDS HANGING ON A LITTLE LONGER THAN EXPECTED
TOO, BUT LIKE CIGS SHOULD SETTLE INTO FORECAST RANGE AROUND 12Z,
TURNING SOUTHWESTERLY LATE THIS MORNING BEFORE SHIFTING MORE
NORTHERLY THIS AFTERNOON.
18
MARINE
AS THE FRONT EXITS, THE DIURNAL PUSHES DOWN THE STRAIT
OF JUAN DE FUCA WILL BE THE MAIN HIGHLIGHT OF THE FORECAST THIS
EARLY MORNING AND AGAIN FRIDAY, AS SCA LEVEL WINDS ARE EXPECTED
DURING EACH TIME FRAME. BEYOND THAT, A THERMAL TROUGH REMAINS
POSSIBLE ALONG THE COAST THIS WEEKEND DUE TO A BUILDING RIDGE OVER
THE AREA AND THE HEATING INVOLVED WITH THAT. THIS WOULD RESULT IN
STRONGER NW WINDS OVER THE COASTAL WATERS.
SEAS 4 TO 6 FEET GRADUALLY EASING DOWN TO 3-5 FT BY TONIGHT. A SHIFT
BACK TO 4 TO 6 FT IS EXPECTED BEFORE THE CLOSE OF THE WEEKEND.
18
FIRE WEATHER
POST-FRONTAL SHOWER ACTIVITY CONTINUES ACROSS THE
NORTHERN AND CENTRAL SOUND AND CASCADES EARLY THIS MORNING. COOLER
AND CLOUDIER CONDITIONS WILL PERSIST TODAY, HELPING TO MITIGATE
FIRE WEATHER CONDITIONS, WITH SHOWERS GRADUALLY TAPERING ACROSS
THE AREA.
THE NEXT ELEVATED FIRE WEATHER CONCERN IS THE HOT AND DRY PATTERN
EXPECTED LATE THIS WEEKEND INTO EARLY NEXT WEEK AS RIDGING BUILDS
IN OVER THE AREA FROM THE PACIFIC. WARMING TEMPERATURES, WITH
HIGHS IN THE 80S TO LOW 90S AND MINIMUM RELATIVE HUMIDITIES DIPPING
DOWN INTO THE 20S AND 30S BY EARLY NEXT WEEK WILL ELEVATE FIRE
WEATHER CONCERNS ACROSS PORTIONS OF THE INTERIOR. ENSEMBLES THEN
SUGGEST TROUGHING REDEVELOPING ACROSS THE REGION AGAIN BY MIDWEEK,
WHICH WOULD HELP MODERATE TEMPERATURES AND INCREASE ONSHORE FLOW.
14
SEW WATCHES/WARNINGS/ADVISORIES
WA...NONE.
PZ...SMALL CRAFT ADVISORY UNTIL 5 AM PDT EARLY 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 3 PM THIS AFTERNOON TO 5 AM PDT FRIDAY
FOR CENTRAL U.S. WATERS STRAIT OF JUAN DE FUCA-EAST
ENTRANCE U.S. WATERS STRAIT OF JUAN DE FUCA.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page