772
FXUS66 KSEW 220510
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
910 PM PST Fri Nov 21 2025

Drier conditions will linger tonight into Saturday for much of
the region. Widespread precipitation - lowland rain, mountain
snow - with breezy winds will move into the area from the North
Saturday night into Sunday. Cooler and unsettled weather will
continue into Monday, with an increased potential for an
organized system mid week into the Thanksgiving Holiday.

&&

.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
A frontal system over British Columbia will kick off the
weekend, resulting in increased clouds over western Washington
and some rain at times across the northern Olympic Peninsula
and northern interior. Onshore flow will increase Saturday
afternoon with breezy winds along the northern coast and
Whidbey Island northward. This will also preclude the relatively
slow shift of the system over British Columbia southward into
western Washington Saturday night into early Sunday morning.
This will bring widespread precipitation and breezy winds
through Sunday. Snow levels Sunday morning will start around
5500-6000 ft gradually lowering to near 2000-2500 ft late Sunday
night. This will set the stage for expected accumulations
across all the mountain passes with a 60-70% chance of 1-2
inches by 10PM Sunday night.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Precipitation - especially over the higher terrain is expected
to linger into Monday - aided by the potential for a post
frontal convergence zone as well as a weak upper level shortwave
expected to clip the region. Snow levels will remain in 1500 to
2000 feet Monday, with storm total accumulations at the passes
in the 4 to 6 in range from Sunday through Monday. Precipitation
will taper off Monday evening with weak ridging is favored to
briefly dry out conditions on Tuesday, with Tuesday morning
looking to be the coldest of the week - some lowland locations
especially away from the water will dip to near freezing.

Ensembles continue to show the potential for a second Pacific
storm system to move into the region mid-week into the
Thanksgiving holiday - bringing another round of widespread
precipitation and breezy/gusty conditions. Snow levels at or
near pass levels on Wednesday would leave the door open for
potential snow accumulations and/or a wintery mix of
precipitation, including a small chance of freezing rain. This
has the potential to cause travel impacts especially for those
traveling across the Cascades ahead of the holiday. Beyond this
ensembles continue to highlight active and potentially
impactful weather through the weekend, especially through the
higher terrain.

&&

.AVIATION...
Upper level ridge weakening through Saturday. Weak front
dropping slowly southeast into the area beginning Saturday
night. Light flow in the lower levels.

MVFR ceilings through Saturday night with local IFR ceilings
mainly coast and Southwest Interior.

KSEA...MVFR ceilings through Saturday night. Southerly winds 4
to 8 knots. Felton

&&

.MARINE...
Seas remain elevated, 10-13 ft, and a Small Craft Advisory
remains in effect for the Coastal Waters and West Entrance
through Saturday (and possibly into Sunday too). Winds through
Saturday will generally range in 10-15 kt with a few gusts to 20
kt in the Northern Inland Waters. Winds will flip to W-SW on
Sunday as a front tracks through. Expect strong winds through
the Strait of Juan de Fuca with gales possible. Onshore flow
prevails early next week with high pressure offshore. Winds will
turn offshore again by Tuesday as the next systems approaches
from the west. 33

&&

.HYDROLOGY...
A weather system will move across western Washington late
Saturday into Monday for lowland rain and mountain snowfall. No
river flooding is expected during this period, but rivers will
rise. The potential exists for additional, heavier precipitation
during the middle of next week. However, uncertainty exists in
both the location and duration of precipitation. River levels
will continue to be monitored during this mid to late week
period.

JD

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 6 AM PST Sunday for Coastal Waters
     From Cape Flattery To James Island 10 To 60 Nm-Coastal
     Waters From Cape Flattery To James Island Out 10 Nm-
     Coastal Waters From James Island To Point Grenville 10 To
     60 Nm-Coastal Waters From James Island To Point Grenville
     Out 10 Nm-Coastal Waters From Point Grenville To Cape
     Shoalwater 10 To 60 Nm-Coastal Waters From Point
     Grenville To Cape Shoalwater Out 10 Nm-Grays Harbor Bar.

     Small Craft Advisory until 4 PM PST Saturday for West Entrance
     U.S. Waters Strait Of Juan De Fuca.

&&

$$