211
FXUS66 KSEW 022157
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
257 PM PDT Sat Aug 2 2025

.SYNOPSIS...Cooler and dry conditions with increased cloud coverage
Sunday through Monday as a shortwave moves across Western
Washington. Upper level troughing over the region Tuesday through
Thursday, with a frontal system bringing back precipitation
chances. Conditions will dry out and become warmer Friday into the
weekend as an upper level ridge builds over the region.

&&

.SHORT TERM /TONIGHT THROUGH TUESDAY/...The marine layer continues
to slowly erode this afternoon. Latest satellite imagery has the
stratus lingering over Puget Sound. Expecting the stratus to scatter
out later this afternoon, giving way to some sunshine this evening.

A shortwave trough will push through the region Sunday through
Monday, marking the beginning of a cooldown and increased
cloudiness. Temperatures Sunday and Monday will be in the low to mid
70s along the interior and upper 50s to low 60s along the coast. The
shortwave will push out of the region Monday evening, however upper
level troughing will remain over the region on Tuesday as an upper
level low begins to descend down the Canadian coastline. The chance
of precipitation returns Tuesday as well; however most of the
precipitation is forecasted to remain west of Puget Sound.

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...Upper level troughing will
continue over the region through Thursday, with a frontal system
bringing more widespread precipitation to Western Washington. Model
guidance currently shows that the highest QPF amounts will be
allocated to the north coast, Olympics, and northern Cascades. High
temperatures Wednesday and Thursday will be in low to mid 70s along
the interior and temperatures along the coast will be in the upper
50s to low 60s. Upper level riding will build over Western
Washington Friday into the weekend. This will dry out conditions
and warm up temperatures. High temperatures on Friday will
rebound to the upper 70s to low 80s along the interior and 60s
along the coast. By Saturday temperatures warm up into the 80s
along the interior (upper 80s possible in the southern interior),
and upper 60s along the coast. 29

&&

.AVIATION...Southwest flow aloft will continue through tonight with
an upper trough offshore. Stratus is clearing across the interior
this afternoon, with an area of lingering stratus around central and
northern Puget Sound. Most areas will improve to VFR this afternoon,
before increasing stratus again tonight into Sunday morning with an
onshore flow pattern at the surface. MVFR/IFR cigs expected to be
widespread again Sunday morning, with localized LIFR as well. Cigs
will slowly improve to VFR for most Sunday afternoon with lingering
mid and high clouds. W/NW winds increasing this afternoon will
become light again tonight.

KSEA...MVFR cigs will improve to VFR generally around 22 to 2230z as
stratus clears. Low-end MVFR to IFR cigs expected again late tonight
through Sunday morning. MVFR cigs may develop as early as 05-06z,
but mainly expected after 10z tonight. Timing for potential IFR cigs
is generally between 12 to 17z Sunday. There is a 15% of LIFR cigs
during this period as well. Southwest winds are expected to
transition to N/NW around 02 to 03z. N/NE winds tonight will become
S/SW Sunday morning. JD

&&

.MARINE...An onshore flow pattern continues through early next week
with high pressure offshore and lower pressure inland. Small Craft
Advisory westerly winds will occur through the Strait of Juan de
Fuca this evening into tonight. There is also a chance for brief
gale force wind gusts this evening in the central to eastern Strait
of Juan de Fuca, but widespread or frequent gusts of this magnitude
are not expected. Another round of SCA west winds may occur Sunday
night as well. A weak weather system will move into the area on
Tuesday and continue through midweek. Seas of 3 to 5 feet for the
Coastal Waters building to 6 feet for the outer Coastal Waters
midweek. JD

&&

.FIRE WEATHER...Low level onshore flow pattern into the middle of the
week combined with upper level trough aloft will give the area cooler
than normal temperatures. Deep marine layer late night and morning
hours will get to the Cascade crest Sunday and Monday. System
arriving Wednesday into Thursday has a chance to give wetting
rains to the Olympic Peninsula and North Cascades. Upper level
ridge building next weekend for the return of drier and warmer
days. Felton

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 5 AM PDT Sunday for Central U.S.
     Waters Strait Of Juan De Fuca-East Entrance U.S. Waters
     Strait Of Juan De Fuca.

&&

$$