277
FXUS66 KSEW 102213
AFDSEW
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
313 PM PDT SUN AUG 10 2025
SYNOPSIS
DRY CONDITIONS AND WELL ABOVE NORMAL TEMPERATURES
ARE EXPECTED THROUGH TUESDAY. THIS WILL RESULT IN A MODERATE
HEATRISK ACROSS THE LOWLANDS AND MOUNTAIN VALLEYS OF WESTERN
WASHINGTON. ONSHORE FLOW WILL RESULT IN COOLER TEMPERATURES
ACROSS THE REGION BY WEDNESDAY AND WILL OPEN THE DOOR FOR
PRECIPITATION TO MOVE BACK INTO THE AREA BY LATE THIS WEEK INTO
THE WEEKEND.
SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/
AS OF 130 PM
TEMPERATURES WERE IN THE 80S ACROSS MOST OF WESTERN WASHINGTON.
THE WARMEST 5-MINUTE ASOS/AWOS OBSERVATIONS WERE 88 AT CHEHALIS
AND 86 AT QUILLAYUTE. THIS WARMTH IS COURTESY OF A BROAD RIDGE
OF HIGH PRESSURE EXTENDING ACROSS THE EASTERN PACIFIC.
LOOKING FORWARD, MONDAY WILL BE PRETTY SIMILAR TO TODAY IN
TERMS OF SENSIBLE WEATHER CONDITIONS WITH TEMPERATURES
INCREASING ANYWHERE FROM 0-5 DEGREES DEPENDING ON THE LOCATION.
OVERNIGHT LOWS WILL LIKELY PEAK MONDAY NIGHT/TUESDAY MORNING,
ONLY DROPPING INTO THE 60S IN MOST AREAS, HIGHEST IN URBAN HEAT
ISLAND AREAS. BY TUESDAY, THE UPPER LEVEL RIDGE WILL BEGIN TO
BREAK DOWN, BUT THE SURFACE REFLECTION WILL TAKE A BIT LONGER TO
FALL IN LINE. A SLIGHT INCREASE IN ONSHORE FLOW IS EXPECTED BY
THE AFTERNOON ALONG THE IMMEDIATE COASTAL AREAS ALLOWING FOR
SOME LOCALIZED COOLING, BUT OTHERWISE THE THERMAL TROUGH WILL
REMAIN ENTRENCHED ACROSS WESTERN WASHINGTON. AS A RESULT,
TEMPERATURES TUESDAY AWAY FROM THE COAST WILL LIKELY INCREASE
ANOTHER 3-5 DEGREES, RESULTING IN THE WARMEST DAY OF THE PERIOD.
LONG TERM /WEDNESDAY THROUGH SUNDAY/
BY WEDNESDAY A WEAK TROUGH
WILL MOVE ACROSS THE REGION, BRINGING NATURAL AIR CONDITIONING
TO THE REGION AND HIGHS WEDNESDAY ARE EXPECTED TO DROP INTO THE
60S ALONG THE COAST AND 70S ACROSS THE REST OF THE LOWLANDS.
ONSHORE FLOW IS FAVORED THROUGH THE LONG TERM PERIOD WITH THE
DOOR REMAINING OPEN FOR SYSTEMS TO TRAVERSE THE REGION. AT THIS
TIME, CHANCES FOR BENEFICIAL PRECIPITATION GENERALLY INCREASE
LATE THURSDAY THROUGH SATURDAY, PEAKING SATURDAY AT 30-50%
ACROSS THE REGION. THAT SAID, CONFIDENCE IN THE DETAILS OF
TIMING AND PLACEMENT OF PRECIPITATION THROUGH SUNDAY ARE
GENERALLY LOW.
-WOLCOTT-
AVIATION
VFR CONDITIONS WILL PREVAIL THROUGH THE REMAINDER OF THE
TAF PERIOD, WITH THE EXCEPTION OF THE COAST. GUIDANCE HINTS THAT
STRATUS/FOG WILL LIKELY SETTLE ALONG THE COAST AFTER 08Z-09Z.
IMPROVEMENT INTO VFR EXPECTED LATE MONDAY MORNING. OTHERWISE, MOSTLY
CLEAR SKIES MONDAY. BREEZY CONDITIONS THIS EVENING 10-14 KT ALONG
PUGET SOUND TERMINALS, WITH WINDS EASING TONIGHT. GUIDANCE HINTS AT
BREEZY CONDITIONS RETURNING MONDAY AFTERNOON/EVENING.
KSEA...VFR CONDITIONS WILL PREVAIL TONIGHT AND MONDAY WITH MOSTLY
CLEAR SKIES. N/NE WINDS 10-12 KT EASING TO 5-7 KT OVERNIGHT. WINDS
WILL SHIFT N/NW MONDAY AFTER 17Z-18Z AT 8-12 KT.
29
MARINE
SURFACE HIGH PRESSURE WILL PERSIST OVER THE COASTAL WATERS
THROUGH WEDNESDAY. A THERMALLY INDUCED SURFACE TROUGH WILL MOVE
ALONG THE COASTLINE TONIGHT AND MOVE INLAND MONDAY AND TUESDAY. HIGH
PRESSURE WILL WEAKEN WEDNESDAY AND A WEAK TROUGH WILL MOVE INTO THE
COASTAL WATERS ON THURSDAY.
A SMALL CRAFT ADVISORY CURRENTLY IN EFFECT FOR THE OUTER COASTAL
WATERS FOR STEEP SEAS 7 TO 8 FEET AT 8 TO 9 SECONDS. SEAS WILL
CONTINUE TO BUILD TONIGHT TO 10 TO 12 FT AND WIND WILL ALSO INCREASE
TO 20 TO 30 KNOTS. GUIDANCE HINTS THAT THERE WILL BE A BRIEF
DECREASE IN SEAS AND WINDS MONDAY AFTERNOON, WITH SEAS AND WINDS
INCREASING EARLY TUESDAY MORNING. ERGO, IT IS HIGHLY LIKELY THE
ADVISORY WILL BE EXTENDED INTO TUESDAY.
GUIDANCE HINTS THAT SMALL CRAFT WESTERLIES ARE POSSIBLE FOR THE
CENTRAL AND EASTERN PORTIONS OF THE STRAIT OF JUAN DE FUCA.
FELTON/29
FIRE WEATHER
A WARMING AND DRYING TREND WILL CONTINUE TODAY
INTO TUESDAY AS AN UPPER LEVEL RIDGE BUILDS OVER THE AREA AND A
WEAK RESULTANT THERMAL TROUGH DEVELOPS ALONG THE COAST. THIS WILL
ALLOW FOR MINIMUM RH VALUES TODAY THROUGH TUESDAY TO DIP AS LOW AS
20-35%, WITH THE LOWEST RH VALUES FROM THE SOUTH PUGET SOUND, THE
SOUTHWEST INTERIOR, AND THE SOUTHERN WASHINGTON CASCADES. A
SHORTWAVE TROUGH LOOKS TO MOVE THROUGH LATER THIS EVENING INTO
MONDAY, AND ALONG WITH THE THERMAL TROUGH, THIS WILL RESULT IN
POORER RH RECOVERIES AND MAY SLIGHTLY INCREASE ATMOSPHERIC
INSTABILITY, POTENTIALLY RESULTING IN MORE ACTIVITY ON OUR ONGOING
FIRES. MORE PERSISTENT TROUGHING IS EXPECTED TO DEVELOP INTO
WEDNESDAY, ALLOWING FOR COOLER AND MORE MOIST AIR TO RETURN TO THE
REGION WITH A SLIGHT CHANCE FOR LIGHT SHOWERS FOR PORTIONS OF THE
NORTH CASCADES AND THE PACIFIC COAST STARTING ON THURSDAY.
62/MAZURKIEWICZ
SEW WATCHES/WARNINGS/ADVISORIES
WA...HEAT ADVISORY UNTIL 10 PM PDT TUESDAY FOR CITY OF SEATTLE-
DOWNTOWN EVERETT / MARYSVILLE AREA-EASTERN KITSAP COUNTY-
EASTERN STRAIT OF JUAN DE FUCA-EASTSIDE-FOOTHILLS AND
VALLEYS OF CENTRAL KING COUNTY-FOOTHILLS AND VALLEYS OF
PIERCE AND SOUTHERN KING COUNTIES-FOOTHILLS AND VALLEYS
OF SNOHOMISH AND NORTHERN KING COUNTIES-FOOTHILLS AND
VALLEYS OF THURSTON AND LEWIS COUNTIES-FOOTHILLS AND
VALLEYS OF THE NORTH CASCADES-FOOTHILLS OF THE WESTERN
AND SOUTHERN OLYMPIC PENINSULA-LAKE CRESCENT AREA
INCLUDING US 101-LOWER CHEHALIS RIVER VALLEY-LOWLANDS OF
LEWIS AND SOUTHERN THURSTON COUNTIES-LOWLANDS OF PIERCE
AND SOUTHERN KING COUNTIES-LOWLANDS OF WESTERN SKAGIT AND
NORTHWESTERN SNOHOMISH COUNTIES-LOWLANDS OF WESTERN
WHATCOM COUNTY-MIDDLE CHEHALIS RIVER VALLEY-NORTHERN HOOD
CANAL-OLYMPIA AND SOUTHERN PUGET SOUND-SHORELINE /
LYNNWOOD / SOUTH EVERETT AREA-SOUTHERN HOOD CANAL-WILLAPA
AND BLACK HILLS.
PZ...SMALL CRAFT ADVISORY UNTIL 6 PM PDT MONDAY FOR COASTAL WATERS
FROM CAPE FLATTERY TO JAMES ISLAND 10 TO 60 NM-COASTAL
WATERS FROM JAMES ISLAND TO POINT GRENVILLE 10 TO 60 NM-
COASTAL WATERS FROM POINT GRENVILLE TO CAPE SHOALWATER 10
TO 60 NM.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page