Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
366
FXUS66 KSEW 280313
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
813 PM PDT Tue Oct 27 2026
.SYNOPSIS...Troughing will persist over the Pacific Northwest
the remainder of today with unsettled conditions and periodic
showers. A frontal system will arrive tonight into Wednesday for
steadier rainfall and mountain snow. An upper low then lingers
over Western Washington into late week for showers and cooler
temperatures.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...The current
forecast remains on track with no planned updates tonight. 33
Previous discussion...Ongoing shower activity will continue
throughout most of the area this afternoon and evening, ahead of
an approaching frontal system. High temperatures this afternoon
generally in the mid to upper 50s across the interior, with low
50s for areas along the water. Showers will turn into more
steadier rainfall starting tonight and continuing into Wednesday
morning. Southwest winds will also increase later this evening
into Wednesday, peaking between 20 to 30 mph generally in the
areas of the Southwest Interior through Shelton. As rainfall
becomes steadier, we will also see the first widespread mountain
snow event of the season unfold. A Winter Weather Advisory
continues for all of the Cascade zones, with snow levels 4000 to
4500 feet dropping to 3000 to 3500 feet by Wednesday morning.
Snowfall accumulations generally around 4 to 8 inches for
Stevens Pass - with Snoqualmie pass seeing around 1 to 3 inches.
Areas in the Southern Cascade Zone such as White Pass and
Paradise will likely see higher amounts, around 6 to 12 inches
of snow. Those traveling will want to be aware of the conditions
and weather by checking with WSDOT for updates.
Upper level troughing will continue Wednesday into Thursday for
spotty showers and cooler temperatures, with high temps ranging
in the low to mid 50s for most areas.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...Ensemble guidance
continues to show troughing across the Pacific Northwest through
Friday, which keeps scattered showers in the forecast. Snow
levels hover around 2500 to 4000 feet on Friday, so could
continue to see light snow accumulations in the Cascades. The
upper level trough looks to slowly move out of the area over the
weekend, with a drying trend over the weekend into early next
week. High temperatures look to remain in the mid 50s over the
weekend. with overnight lows approaching low to mid 30s. Will
continue to monitor the threat of frost or freeze conditions.
Mazurkiewicz
&&
.AVIATION...Convergent bands of rain continue to move east into
the Cascades this evening in Snohomish County. Pockets of IFR
ceilings linger in wake of the convergence zone between Everett
and Mt. Vernon. Additional showers are working their way inland
from the coast and will impact some of the Puget Sound terminals
over the next several hours. Gusty winds continue out of the
southwest at 25 kt, and will linger through late tonight. Light
RA will return to inland terminals after 05Z with another round
of lower cigs expected tomorrow morning. Probabilities of cigs
less than 3000 ft are around 60-80% tonight after 06Z and 45-55%
tomorrow morning between 15Z- 18Z.
KSEA...Gusty southwest winds will continue through roughly 05Z, with
gusts to 20 to 25 kt. Mix of VFR and MVFR ceilings this evening.
Rain will return late tonight and become more scattered after 09Z.
Vicinity showers will persist through the end of the TAF period with
MVFR cigs expected until tomorrow afternoon.
21/HPR
&&
.MARINE...Northwesterly winds along the outer coastal waters
will linger into Wednesday, with wind gusts approaching 25 kt at
times and a SCA still in effect until late tonight. Seas will
be between 8-9 feet overnight. Another frontal system will move
into the waters tonight into Wednesday, increasing winds and
seas across the area. Increasing onshore flow will bring a brief
push of small craft westerly winds to the central and eastern
Strait late this afternoon into this evening. Southerly winds
are picking up along the Puget Sound waters this afternoon, with
latest guidance highlighting a 60- 80% chance of gusts
exceeding small craft criteria particularly in the waters from
Seattle south.
Winds will ease again across the area waters on Wednesday as the
accompanying surface low drops into the area and tracks southward
along the coastal waters. This low will allow for flow to turn back
offshore, with offshore flow persisting the second part of the week.
Sea conditions slowly subsiding back to 4-6 ft on Thursday and
remain that way into the weekend.
21
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Winter Weather Advisory until 5 PM PDT Wednesday for Cascades
of Pierce and Lewis Counties-Cascades of Snohomish and
Northern King Counties-Cascades of Southern King County-
Cascades of Whatcom and Skagit Counties.
PZ...Small Craft Advisory until 11 PM PDT this evening for Central
U.S. Waters Strait Of Juan De Fuca-East Entrance U.S.
Waters Strait Of Juan De Fuca-Puget Sound and Hood Canal.
Small Craft Advisory until 5 AM PDT Wednesday for Coastal
Waters From Cape Flattery To James Island 10 To 60 Nm-
Coastal Waters From James Island To Point Grenville 10 To
60 Nm-Coastal Waters From Point Grenville To Cape
Shoalwater 10 To 60 Nm.
&&
$$
NWS SEW Office Area Forecast Discussion