Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
397
FXUS66 KSEW 231639
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
839 AM PST Sun Nov 23 2025
.SYNOPSIS...Post-frontal showers through today, especially over
the Cascades and with a convergence zone in central Puget Sound.
The trough axis will shift inland on Monday for additional
showers. A wetter system will move into the region Wednesday and
Thursday, bringing in heavier lowland rain and mountain snow
that may cause holiday travel impacts in the Cascades. Cooler
and unsettled conditions will continue into next weekend.
&&
.SHORT TERM /TODAY THROUGH TUESDAY/...The cold front that moved
across Western Washington early this morning continues to slide
east of the area. Continued precipitation is expected at times
today in the Cascades. A convergence zone is also developing
over King/Snohomish County, and will linger into this evening
between Everett and SeaTac, with the bulk of the precipitation
in the central Cascades. No major forecast updates, previous
discussion below:
The upper trough axis will push inland early Monday morning,
bringing in additional showers through Monday afternoon. Snow
levels starting around 5000-5500 feet early this morning will
lower to around 2000-2500 feet by this evening, resulting in a
few inches of accumulating snowfall through the Cascade mountain
passes. Through Monday, the lowlands will generally see up to a
half inch of rainfall, while the mountains will see roughly 3
to 5 inches of snow above 2500 feet. Temperatures through Monday
will peak within a few degrees of normal for late November,
with highs in the upper 40s to lower 50s across the lowlands.
Monday evening through Tuesday morning will bring a brief break
in active weather as weak high pressure builds into the Pacific
Northwest. Tuesday morning will see the coldest morning
temperatures of the upcoming week, with many lowland areas
especially away from the water dipping to near freezing. Despite
dry conditions, Tuesday morning is likely to be a typical
cloudy and foggy fall morning across western Washington.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...A warm front will
lift northward across western Washington Tuesday evening into
Wednesday as the next storm system brings subtropical moisture
into the region. Snow levels starting around 2000-3000 feet will
lift above 4500-5500 feet by late Wednesday with the warm
front, then fall below 4000 feet later in the week. However,
there still remains a bit of uncertainty over the track and
orientation of the warm front and how quickly temperatures rise
over the Cascades. East flow through the Cascade gaps may result
in a brief period of a wintry mix or freezing rain through the
mountain passes, but precipitation over higher elevations will
likely predominantly be snow. Snow accumulations through the
higher Cascade passes may reach a foot or more by the
Thanksgiving holiday, resulting in very difficult travel
conditions. Anyone traveling over the Cascades next week is
strongly urged to use caution and stay up to date on the latest
weather conditions and forecasts. Across the lowlands, rainfall
amounts of over an inch in 24 hours may also cause localized
ponding in urban areas and areas with poor drainage, also posing
travel impacts during the Thanksgiving holiday. However,
widespread flooding is not expected through the week.
Forecast uncertainty increases towards the end of the week as
some ensemble members bring in another wet weather system while
other members build a sharp high pressure ridge offshore. For
now, have maintained chances for additional precipitation in the
forecast with potential for much cooler temperatures by the end
of next weekend.
15
&&
.AVIATION...A frontal system has pushed through the terminals
this morning, with the majority of precipitation now to the
east. Some light showers still possible behind the front today.
Ceilings should improve to low-end VFR (first along the coast,
then for portions of the south/north interior after 00Z). Caveat
will be for Puget Sound terminals under the convergence zone,
with MVFR continuing through at least 06Z. Another trough on
Monday will produce a few showers, and bring a mix of VFR/MVFR
ceilings in the morning. Flow aloft through the period will
remain out of the west. Winds behind the front will turn W/NW
through the morning and afternoon (starting with the coast,
progressing eastward). Winds will decrease to 4-6 kt in the
afternoon, and remaining at 4-6 kt overnight(gustier in the
Strait of Juan de Fuca however).
KSEA...Shower activity will consolidate to a convergence zone around
19Z, with showers/vicinity showers continuing through 06Z Monday.
This will likely keep ceilings MVFR up to that point, before
improving to VFR late Monday night. Winds expected to turn NE at 4-6
kt as early as 19Z due to the convergence zone. Southerly surface
winds return after 06Z at 4-7 kt.
HPR/29
&&
.MARINE...A cold frontal system is moving east of the waters
this morning. Few lower ceilings and visibility drops due to
the showers/low clouds are likely for short periods this
morning. The central/east Strait of Juan de Fuca are expected to
see frequent gusts over 20 kt much of Sunday through late
Monday morning. The coastal waters will continue to see gusts
over 20 kt through Sunday evening before seeing light winds.
Seas are expected to 6 to 8 ft Monday afternoon.
A larger system approaches the waters late Tuesday through Wednesday
and into Thanksgiving. The Strait of Juan de Fuca and coastal waters
have the highest probabilities of seeing winds/wind gusts exceed 20
kt during this period (but the threat for gales remain low). Seas
will increase back to 8 to 10 ft Wednesday, but drop to 6 to 8 ft
Thursday through the remainder of the week.
JD/HPR
&&
.HYDROLOGY...A weather system will continue to move across western
Washington into Monday for lowland rain and mountain snowfall.
No river flooding is expected during this period, but rivers
are expected to rise. Heavier precipitation is likely beginning
late Tuesday through Thursday of next week. Snow levels will
also rise to 4500 to 5500 feet by Thursday, resulting in
additional rises to area rivers. At this time, the Skokomish
River in Mason County is forecast to approach flood stage
midweek. Although no additional river flooding is forecast at
this time, rivers will continue to be monitored.
JD
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 10 PM PST this evening for Grays
Harbor Bar-West Entrance U.S. Waters Strait Of Juan De
Fuca.
Small Craft Advisory until 7 AM PST Monday for Central U.S.
Waters Strait Of Juan De Fuca-East Entrance U.S. Waters
Strait Of Juan De Fuca.
Small Craft Advisory until 10 AM PST Monday 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.
&&
$$
NWS SEW Office Area Forecast Discussion