Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
538
FXUS66 KSEW 231559
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
859 AM PDT Wed Sep 23 2026
.SYNOPSIS...
Onshore flow will maintain cooler temperatures and cloudy skies
through Thursday, with some light showers across the area this
morning. A stronger system will bring more widespread rain
across western Washington Thursday into Friday. Cooler and
unsettled conditions will continue through the weekend, with
additional chances for precipitation expected into next week.
&&
.SHORT TERM /TODAY THROUGH FRIDAY/...
Broad upper level troughing will continue over western
Washington for one more seasonable day. A weak frontal system
moving through the region this morning has brought some light
showers to portions of the area, most notably across Whatcom
County over the past hour. Low clouds this morning will
continue through late morning before dissipating, leading to a
mix of high clouds and sun this afternoon. High temperatures
will reach in the mid to upper 60s today, with areas along the
coast seeing low 60s due to the marine layer.
A frontal system will cross over the area Thursday into Friday,
bringing widespread rain to much of region. Showers will start
Thursday afternoon with rain becoming more widespread overnight
into Friday morning. Most lowland locations will see roughly a
half an inch of rainfall, with areas in the Cascades and
Olympics seeing closer to an inch of rainfall. With snow levels
dropping to 6000-7000 feet on Friday, some of the higher peaks
may even see the first dusting of snow of the season. Showers
will likely continue throughout the day Friday as the upper
level trough axis shifts east of the Cascades.
High temps will cool both on Thursday and Friday, in the upper
50s, with some locations struggling to hit 60 degrees in true
fall fashion.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...Conditions will dry
out slightly on Saturday as a weak upper level ridge builds over
the region. These dry conditions seem temporary, as latest
ensemble guidance maintains additional chances for precipitation
into the first half of next week, with upper level troughing
likely returning to the Pacific Northwest for cooler and wetter
conditions.
Mazurkiewicz
&&
.AVIATION...
A weak cold front will swing through the terminals today, with high
pressure briefly rebuilding in its wake. A few lines of showers will
move along the coastal and northern interior terminals this morning
with this front. Model guidance favors a mixture of low VFR and MVFR
ceilings and light southerly winds 5-10 kt this morning with
isolated pockets of IFR CIGs/VIS (primarily in the Cascades and
southwest interior). Conditions become VFR favoring north/northwest
winds after the front moves through. A similar mix of low VFR/MVFR
is expected Thursday morning ahead of a wet system moving through
late Thursday & Friday with rain.
KSEA...VFR conditions favored through the TAF period (although brief
MVFR ceilings cannot be completely ruled out). Southerly winds 5-10
kt turning to the north this afternoon (currently expected around
00z). Wet conditions with lower CIGs are expected late Thursday
through Friday.
Wolcott
&&
.MARINE...
A weak cold front will progress over the waters this morning
with showers and no significant wind or sea impacts. High
pressure will briefly rebuild offshore with another push through
the Strait of Juan de Fuca this evening. A more organized
system will move through Thursday into Friday with more
widespread rain, and an increased risk of winds exceeding 20 kt
for the coastal waters and Strait of Juan de Fuca. Winds
decrease going through the weekend into next week, and another
weak front may pass over the waters over the weekend.
Expect seas to range from 5-8 feet through Thursday, and increase to
9-10 feet Friday with the system moving through. The seas will
decrease to 4-6 feet this weekend/early next week.
HPR
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...None.
&&
$$
NWS SEW Office Area Forecast Discussion