Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
928
FXUS66 KSEW 260322
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
822 PM PDT Sun Oct 25 2026
.UPDATE...
No changes made in this evening`s update. The previous
discussion remains below along with an updated aviation section.
&&
.SYNOPSIS...
A weather system offshore will drift southwards
into Monday and move onshore across NW Oregon resulting in
continued scattered showers. Unsettled conditions Tuesday with
continued troughing. A frontal system midweek will bring
increased lowland rain and mountain snowfall into late week.
Cooler temperatures next weekend.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
Steadier precipitation continues this afternoon over portions
of the Cascades and coast as a low pressure system offshore
slowly drifts southwards. Unsettled conditions with periodic
showers continue through Monday as the system weakens and moves
onshore into NW Oregon by Monday afternoon. Snow levels remain
near 5000 feet for high elevation mountain snowfall in heavier
showers. Otherwise, winds will slowly subside for breezy areas
of the coast and Admiralty Inlet into tonight. Highs remain in
the 50s for most areas this afternoon and again Monday.
Troughing persists over the Pacific Northwest on Tuesday, with
lingering moisture and a few showers over the Cascades
throughout the day. The next frontal system also approaches from
BC later Tuesday into Tuesday night bringing increasing
precipitation and locally breezy winds. Highs continue in the
mid 50s Tuesday.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
The aforementioned
frontal system moves across Western Washington Tuesday night
into Wednesday. This looks to be the first noticeable mountain
snowfall event of the season as colder air filters into the area
with this system. Snow levels during the bulk of the
precipitation ranges between 3500 to 4500 feet, allowing for
snow at the higher elevation Cascade Passes. NBM probabilities
for greater than 6 inches of snow (24 hours ending 500 PM
Wednesday) is approximately 70% at Heather Meadows (Mt. Baker),
15% at Rainy Pass, 20% at Stevens Pass, and 90% at Paradise,
with most of the snowfall between Tuesday evening into early
Wednesday. Will need to monitor the need for any headlines for
this event, both due to early season, and higher snowfall
amounts above 4500-5000 feet. Otherwise, lowland rainfall is
expected on Wednesday, with a 15% probability for thunderstorms
for most of the lowlands.
The associated upper low will then deepen offshore Thursday and
linger over the WA/OR waters into late week for continued
unsettled conditions. Ensembles are generally consistent the
troughing digs even further southwards late Friday into next
weekend, lowering the precipitation potential. However, cooler
temperatures are then expected over the weekend, and will need
to monitor any frost or freeze concerns during the morning. JD
&&
.AVIATION...
Southwesterly flow aloft will become southeasterly overnight as
an upper low offshore moves southward and then onshore over
northwest Oregon on Monday. Latest radar shows the heaviest
bands of precipitation along the coast this evening, with some
light shower activity across parts of the interior lowlands.
Showers will continue across the area into Monday. Ceilings
remain a mixed bag of mostly low-end VFR to MVFR across the
region this evening as a result. MVFR ceilings will become more
widespread by early Monday as ceilings lower overnight.
KSEA...Mostly low-end VFR ceilings this evening in shower
activity. This trend will continue through tonight before a more
widespread lowering of MVFR ceilings occurs overnight into
Monday morning. Latest probabilistic guidance indicates a 45%
chance of ceilings dropping to MVFR by 12Z, with a 10-20% chance
of ceilings dropping to IFR at the terminal. SE winds primarily
between 5-10 kt this afternoon will become more NE tonight and
ease to 5 kt or less overnight into Monday.
14/41
&&
.MARINE...
A gradually weakening surface low over the offshore
waters will continue to make its way southward tonight before
moving onshore over the northern Oregon coast on Monday. Small
craft advisories remain in effect for a combination of wind and
seas over the coastal waters through tonight. Small craft
advisories also remain in effect for east/southeasterlies along
the Strait of Juan de Fuca. Winds will ease tonight and flip
back to onshore on Monday as the low weakens and continues
southward.
Another front will reach the waters on Wednesday as another low
moves into the region and southward along the coastal waters.
This system will likely bring the next round of headlines to
portions of the area waters as well as the return of offshore
flow to the waters through the second half of the week.
Seas will continue to hover between 9-12 ft today and will gradually
subside to 3-6 ft on Monday. Seas will then briefly build back
up to 7-9 ft near midweek, before subsiding back to 4-6 ft on
Thursday and persisting between this range over the weekend.
14
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 11 PM PDT this evening for Central
U.S. Waters Strait Of Juan De Fuca-Grays Harbor Bar-West
Entrance U.S. Waters Strait Of Juan De Fuca.
Small Craft Advisory until 3 AM PDT 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