828
FXUS66 KSEW 020312
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
812 PM PDT Fri Aug 1 2025

.SYNOPSIS...Light showers possible along the far northern Cascades
this evening. An upper level trough will bring cooler temperatures
and the chance of rain next week. Ridging will build over the
region on Friday bringing warmer and drier conditions.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY/...Conditions are rather quiet
this evening, with thunderstorm activity all staying well east of
the Cascade crest. A few light showers are still possible across
the far northern Cascades this evening, but not expecting much in
the way of activity overall. Satellite imagery shows stratus already
starting to move inland along the coast this evening. Expect stratus
to push into the Sound overnight for a cool and cloudy start to
Saturday morning. The forecast remains largely on track this evening.
The previous discussion follows below, with updates made to the
aviation and marine sections. 14

A gradual cooldown ensues Saturday as a shortwave trough prepares
to enter Western Washington. As the shortwave moves through the
region Sunday and Monday, expect increased cloud cover and
temperatures in the low to mid 70s along the interior.
Temperatures along the coast will be in the upper 50s to low 60s.

.LONG TERM /TUESDAY THROUGH FRIDAY/...A troughing pattern is
favored into late next week. This will bring the chance of
precipitation back into the forecast and keep temperatures on the
cooler side. High temperatures will be in the 70s along the
interior and 60s along the coast. Upper level riding is favored to
build over the region Friday, bringing warmer and drier
conditions. High temperatures on Friday will rebound to the mid to
upper 70s along the interior, with some locations possibly
reaching the low 80s along the southern interior. Coastal high
temperatures will be in the mid to upper 60s.

29

&&

.AVIATION...Southwesterly flow aloft will continue with a large
closed low over the Gulf of Alaska. VFR for all terminals except for
the coast this evening, with an expected intrusion of stratus
overnight. Stratus is likely to make it to western Puget Sound by
09Z. Stratus will begin to reform along the coast and push inland
across most of the interior by tomorrow morning blanketing the area
with low-end MVFR to IFR ceilings, with perhaps some local LIFR
cigs, especially near the coast. Ceilings will be slower to burn off
compared to today, but should have mostly VFR conditions between 18-
21Z with mostly clear skies by Saturday evening. Light W/SW winds in
most areas, except becoming NW through the Puget Sound this
afternoon. Strongest winds near HQM and through the Strait of Juan
de Fuca up through BLI this evening. Winds become light and variable
overnight before the pattern starts again, though winds will be a
few knots stronger.

KSEA...VFR conditions will prevail through this evening. Stratus
will redevelop over the terminal by 12-14Z Saturday morning,
lasting through around 18-20Z. Ceilings will lift to VFR but will
slowly scatter throughout the afternoon. W/SW winds, 4-8 kt, will
veer to NW this evening, becoming light N/NE overnight. Winds
then go back to SW Saturday morning as the wind pattern remains
the same during the day Saturday.

62/21

&&

.MARINE...Broad high pressure over the area waters will maintain
onshore flow through the weekend. The strongest winds will be
through the Strait of Juan de Fuca where there will be diurnally
driven pushes of westerlies each evening. A Small Craft Advisory
is in effect this afternoon through much of tonight. Another
slightly stronger push will likely require additional headlines
tomorrow night. A frontal system looks to approach the region on
Monday then move through the area Tuesday into Wednesday.
Additional systems are possible later in the week.

Waves will remain 5 ft or less through the next 7 days.

With stronger onshore flow tonight, low stratus should be the
main feature over the waters tonight, though there could be some
localized areas of reduced visibility, especially late this
evening through around midnight.

62/21

&&

.FIRE WEATHER...Western Washington transitioning into a cooler
pattern over the weekend. Low level onshore flow increasing
Saturday. Deeper marine layer giving the area late night and
morning clouds with good RH recoveries each day through at least
Thursday. Weak upper level trough moving through Monday with a
weak front trying to hang together for the middle of next week.
Upper level ridge building the second week of August with the
possibility of another very warm and dry spell. Felton

&&

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

&&

$$