Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
839
FXUS66 KSEW 101703
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
1003 AM PDT Tue Mar 10 2026
.SYNOPSIS...
Rain out ahead of the next system reaching the area this
afternoon with rain in the lowlands and snow in the mountains
through Wednesday. Strong cold front moving through late
Wednesday afternoon/Wednesday evening bringing blizzard
conditions to the mountains and windy conditions to the
lowlands. Atmospheric river taking aim at Western Washington
beginning Thursday. The river will sag south late Friday night
or Saturday morning. Upper level ridge building offshore Sunday
and Monday with a warm front moving over the top of the ridge.
&&
.SHORT TERM /TODAY THROUGH THURSDAY/...
No major changes to the forecast have been made this morning.
There is potential for more widespread wind for the system
impacting the area Wednesday into Thursday. Model guidance has
suggested an increased likelihood in gusts of 35 to 40 mph up to
45 mph across the lowlands. This will be evaluated before the
next forecast goes out. Otherwise, the rest of the previous
discussion can be found below, as well as an update to the
aviation sections.
Upper level trough remaining over Western Washington today.
Temperatures are cold enough this morning for lowland snow
showers but there is limited moisture. Best chances for snow
showers this morning will be in the dissipating convergence zone
and in the western portion of Clallam county. Increasing clouds
for the remainder of the area. Upper level shortwave approaching
from the northwest later this morning with rain out ahead of
the shortwave spreading over Western Washington this afternoon.
In addition to the rain it will be a breezy day with wind gusts
in the 30 mph range common in the afternoon. High remaining
cool, in the mid 40s.
Shortwave moving through tonight followed quickly by another
system Wednesday spreading rain back over the area. Western
Washington still on the cool side of the jet with snow levels
remaining below the passes. New snow totals in the Cascades from
this morning through Wednesday afternoon in the one to two foot
range. Lows tonight in the mid 30s to lower 40s. Highs Wednesday
near 50.
Sharp cold front moving through early Wednesday evening
producing a variety of impactful weather. In the mountains model
850 mb winds in the 40 to 55 knot range just ahead, with and
behind the front. This will produce blizzard conditions in the
passes into early Thursday morning with another foot plus of new
snow by sunrise. Along the coast strong post frontal westerlies
with wind gusts as high as 55 mph. A wind advisory has been
issued. Strong push through the Strait of Juan de Fuca as well.
It`s possible a wind advisory will be needed for the Admiralty
Inlet area and Whidbey Island. Windy conditions for the
remainder of the interior with wind gusts in the 30-40 mph
range. Rain turning to showers behind the front. Lows near 40.
Little in the way of a break in the weather Thursday as an
atmospheric river takes aim at Western Washington while the
some cool for atmospheric river conditions air is still in place
over Western Washington. Snow levels around 3000 feet with
heavy snow likely in the Olympics and the Cascades. A winter
storm watch remains in effect for the mountains beginning
Thursday. In the lowlands another round of rain. Highs in the
mid 40s. Felton
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Extended models in good agreement with the atmospheric river
remaining over Western Washington until at least Friday night.
Winter storm watch for the mountains remains in effect through
Friday night. There is a good chance the mountains will see
another two to three feet of snow between Thursday and Friday
night. Upper level ridge building offshore pinching the river
off and pushing it south later Friday night into Saturday.
Possible break Sunday but right now more of the ensemble
solutions pointing towards another atmospheric river getting
over the top of the upper level ridge offshore moving into
Western Washington Sunday night and Monday. Felton
&&
.AVIATION...
Westerly flow aloft throughout the TAF period. VFR cigs are present
across most western Washington terminals outside of areas of fog
creating areas of LIFR fog that should burn off later this morning.
Conditions are favored to begin to deteriorate to MVFR towards 21z-
00z as rainfall increase across W WA. MVFR to IFR cigs overnight
into Wednesday morning as well. Surface winds are forecast to
increase this afternoon with southerly gusts up to 20-30 kt for area
terminals except for KCLM.
KSEA...VFR cigs this morning before MVFR cigs redevelop (afternoon-
early evening) and continue into early Wednesday as rain increases
across W WA. Southerly gusts increase around 18-20z around 20-25 kt
and remain elevated into the evening.
McMillian/15
&&
.MARINE...
Pre-frontal southerly winds will continue to pick up this morning as
SCAs have been issued for Puget Sound, Admiralty Inlet, East Strait
and Northern Inland waters for today. SCAs for the coastal waters
and Grays Harbor bar remain in effect as well due to winds and seas.
A much stronger disturbance is on tap to arrive on Wednesday with
the potential for widespread gale force winds. A brief window of
storm force gusts are also possible as hi-res guidance is showing a
30-50% chance of them occuring over the Central and Eastern Strait
on Wednesday evening. A weaker system will stall over the region
Thursday and Friday. The flow will turn northerly on Saturday, then
offshore on Sunday as a warm front moves into southern B.C.
Seas 8-13 ft today before rising to 10-15 ft Wednesday night. Seas
then fall below 10 ft by Thursday afternoon and remain thereafter.
McMillian
&&
.HYDROLOGY...
Moderate to heavy precipitation over the Olympics will cause
the Skokomish River in Mason County to rise today with flooding
possible beginning Wednesday. The river will remain high
through the end of the week. Flooding is also possible on the
Chehalis river from Grand Mound to Grays Harbor, Newaukum River
and Skookumchuck River near Bucoda beginning Thursday. Crests
on these rivers will occur Friday into the weekend. Several
other rivers from Snohomish county southward are forecast to
reach Action Stage later this week. The lower snow levels with
the atmospheric river Thursday through Friday will make river
forecasting tough during this event. After a short break it is
possible another atmospheric river will move over the area early
next week. With the already high running rivers ahead of the
event this will be closely watched for another round of
possible river flooding. Felton
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Winter Weather Advisory until 6 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.
Blizzard Warning from 6 PM Wednesday to 5 AM PDT Thursday 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-
Olympics.
Winter Storm Watch from late Wednesday night through late
Friday night 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-Olympics.
Winter Weather Advisory until 11 AM PDT this morning for
Foothills and Valleys of Snohomish and Northern King
Counties-Lake Crescent Area Including US 101-Western
Strait of Juan de Fuca.
Flood Watch from Wednesday afternoon through Thursday
afternoon for Foothills of the Western and Southern
Olympic Peninsula-Middle Chehalis River Valley-Olympia
and Southern Puget Sound-Olympics-Southern Hood Canal-
Willapa and Black Hills.
Wind Advisory from 6 PM Wednesday to 6 AM PDT Thursday for
Grays Harbor County Coast-Northern Washington Coast.
PZ...Small Craft Advisory until 5 PM PDT this afternoon for Grays
Harbor Bar.
Gale Watch from Wednesday afternoon through late Wednesday
night for Central U.S. Waters Strait Of Juan De Fuca-East
Entrance U.S. Waters Strait Of Juan De Fuca-West Entrance
U.S. Waters Strait Of Juan De Fuca.
Small Craft Advisory until 8 PM PDT this evening for Admiralty
Inlet-East Entrance U.S. Waters Strait Of Juan De Fuca-
Northern Inland Waters Including The San Juan Islands.
Small Craft Advisory until 11 PM PDT this evening for Puget
Sound and Hood Canal.
Small Craft Advisory until 2 PM PDT Wednesday 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.
Gale Watch from Wednesday afternoon through Wednesday evening
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