210
FXUS66 KSEW 081548
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
848 AM PDT Wed Oct 8 2025

.SYNOPSIS...Cool and cloudy conditions will settle into western
Washington with periods of showers through the week as a low
deepens offshore. More widespread precipitation will enter the
region over the holiday weekend, with the first mountain snow of
the season.

&&

.SHORT TERM /TODAY THROUGH FRIDAY/...A mix of clouds and
clearing across Western Washington this morning as an upper
trough deepens offshore. A few showers may be around today, but
predominantly dry conditions expected through this evening.
Increasing southerly flow aloft will result in increased shower
potential tonight into Thursday. No major forecast updates this
morning. Previous discussion below.

An upper level trough will lower along the Pacific Coast from
the Gulf of Alaska through the remainder of the week, bringing
in much cooler temperatures, cloudy skies, and periods of light
shower activity. As the low strengthens and slowly creeps
southward along the coast, wrap around moisture will be advected
northward into western Washington to generate ample cloud cover
and light shower activity. Today is favored to be the driest
day of the period, with isolated showers confined to the
Cascades. Rain showers will increase in coverage on Thursday and
once again on Friday, with generally light rainfall totals.
Temperatures through the rest of the week will cool to more
fall-like conditions, with highs in the upper 50s to low 60s
across western Washington.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...Ensembles continue
to show good agreement over a more active pattern emerging into
the weekend as the offshore low tracks inland and another
trough drops down from British Columbia. Temperatures over the
weekend and into early next week will cool even further, with
most areas seeing high temperatures below 60 degrees. As more
widespread precipitation enters the region, the cooler air will
lower snow levels to roughly 4000-5000 feet. This will bring a
few inches of accumulating snow to higher elevations, with
mountain passes in the North Cascades seeing the best shot at
accumulating snow on the roads. Surface temperatures may still
be too warm to see much impact through Stevens and Snoqualmie
Passes, but any recreationists heading to the higher elevations
of the Cascades and Olympics over the holiday weekend should
prepare for snow and much cooler temperatures.

Unsettled and cooler conditions are forecast to continue on into
early next week, with ensembles showing another low pressure
system moving into the Pacific Northwest. However, models show a
large spread of solutions beyond Monday.

15

&&

.AVIATION...Southerly flow aloft as an upper level low continues to
spin just offshore. A mix of VFR and MVFR continues this morning as
stratus has filled in throughout the interior lowlands from
Seattle/Bremerton and northward. MVFR cigs will likely continue for
these locations through the morning before lifting and scattering
towards 19-20z. VFR conditions will continue through the day
and tonight. Increasing mid level clouds tonight into early
Thursday morning should keep widespread fog/low cloud concerns
mostly at bay. Light winds winds this morning will become
south/southwesterly 4 to 8 kt during the day.

KSEA...MVFR cigs continue this morning and will persist through much
of the morning, lifting and breaking out after around 18-20z. VFR
conditions prevail through the remainder of the period. Mid and high
level clouds will increase late tonight into early Thursday morning.
Calm winds this morning will become southwesterly 5-8 kt late this
morning through this evening. Winds become light north/northeasterly
4 kt or less after 03Z Thursday through the overnight period.

62/McMillian

&&

.MARINE...A mostly dry cold front has traversed across western
Washington, keeping northwesterly winds going across the coastal
waters. Seas 7 to 12 will continue through today, with seas
remaining steep with a dominant period of 8 seconds. Winds will ease
below Small Craft Advisory level late this morning, with seas
following suit, lowering below 7 ft this evening. A low pressure
system will form over the offshore waters on Thursday. The system
will move onshore to the southwest Friday into Saturday but weaken
as it does so.

Winds will become offshore on Thursday and Friday as the low
pressure system remains over the waters. Seas remain around 5-7 ft.
As it moves inland, winds will return to being onshore and
strengthen. Additional headlines will likely be needed on Saturday
with high probabilities (60-80%) for gale force winds across the
coastal waters as well as the central Strait of Juan de Fuca. Seas
will also increase, building up to around 12-15 ft, with the highest
seas over the northern portions of the coastal waters.

Another system may develop Sunday night into Monday over the region,
bringing another round of breezy winds, but model discrepancies
increase at this time range.

62

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 2 PM PDT this afternoon 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.

&&

$$