Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
777
FXUS66 KSEW 010955
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
255 AM PDT Wed Apr 1 2026
.SYNOPSIS...
A weather system will move into the region today, bringing
lowland rain, mountain snow, and gusty winds to the western
Washington. Showers will linger across the Cascades into
Thursday before a ridge of high pressure builds back into the
region and brings warmer and drier conditions to the area Friday
and into early next week. A pattern change is possible by
Tuesday as troughing looks to move back into the region.
&&
.SHORT TERM /TODAY THROUGH FRIDAY/...
A low pressure system dropping southward along the BC coast
will swing a frontal system across western Washington today.
This system will bring the next round of lowland rain, mountain
snow, and gusty winds to the area. Radar this morning is already
showing some shower activity moving northward across the region
ahead of the system and observations have started to show winds
picking up over the coastal waters this morning. Additional
details regarding the hazards have been outlined below:
Winds: Expect winds to continue to increase along the coast
and the eastern Strait through the early to mid-morning hours.
The strongest winds are expected to be along the Pacific Coast
and for areas from Whidbey Island northward, including the San
Juans, where gusts between 35-40 mph will be possible at times.
Elsewhere, winds will be breezy, with winds gusts between 20-30
mph expected as the front moves through. Winds will remain
elevated through the early afternoon hours, before easing during
the late afternoon and evening. The exception remains along the
Strait of Juan de Fuca, where a post-frontal push will keep
westerly winds breezy for areas along the Strait this evening
and into Thursday morning.
Rain: Showers will continue to move into the area ahead of the
frontal system early this morning. Expect more widespread,
steady rain to spread inland along the coast between 11-14Z and
to make its way inland into the interior between 16-19Z. Steady
rain will become more showery in the front`s wake, with showers
continuing across the area through the evening hours. Overall
rainfall amounts remain in the ballpark of 0.25-0.75 inches for
areas across the interior and between 0.5-1 inch for areas along
the coast.
Mountain Snow: Snow levels around pass level will rise to around
4000-4500 ft by late morning, before falling below pass levels
by late tonight. Overall snowfall accumulations for the passes
look to remain between 4-8 inches, with the the majority of the
snow expected to fall at pass level late this evening and
through Thursday morning.
The parent low will then move inland across the region late
tonight into Thursday morning. Wrap-around moisture from the low
will keep light snow showers going across the Cascades through
the late afternoon and early evening hours before tapering.
Conditions across the lowlands will largely dry out on Thursday,
with a few sunbreaks expected by the afternoon amongst mostly
cloudy skies. High temperatures are expected to be in the 50s.
A shift to warmer and drier conditions commences on Friday as
a ridge of high pressure starts to build into western Washington.
While a weak weather system moving into BC may clip the North
Coast and Northern Interior on Friday, expect the majority of
the area to remain dry. Afternoon highs will warm a couple of
degrees and look to top out in the mid to upper 50s.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Ensembles remain in good agreement with a ridge of high pressure
building over the region through the weekend. This will continue
to promote a warming and drying trend across western Washington,
with afternoon highs expected to warm a couple of degrees each
day and to top out in the mid to upper 60s by Sunday. While
forecast details become a bit more unclear heading into early
next week, ensembles continue to hold on to the warmer trend on
Monday as the ridge axis moves inland. At this time, Monday
looks like it may be the warmest day across the interior, with
afternoon highs expected to approach the upper 60s to near 70
for areas south of the Sound and along the Cascade foothills.
Guidance then starts to hint at an upper level shortwave approaching
the area by Monday afternoon, but will need to see how this
trend evolves in the coming days. Either way, a pattern change
looks to arrive by Tuesday as upper level troughing looks to
move back into the region.
14
&&
.AVIATION...
Southwest flow aloft as a frontal system enters the region this
morning. Mostly VFR observed but MVFR/IFR will likely increase in
coverage today as widespread rainfall enters the region. Showers are
developing throughout the interior at this hour but steadier rain is
on tap, starting at the coast around 11-14z and inland by 16-18z.
Surface winds become southerly and increase as the front approaches.
Stronger gusts to around 25 kt are more likely for KHQM and KBLI.
VFR/MVFR cigs are to remain overnight into Thursday as rain
showers maintain.
KSEA...VFR with increasing mid level clouds so far this morning.
Surface winds 3-6 kt this morning, increasing 8-12 kt around 00z
with brief gusts up to 20 kt possible. A mix of VFR/MVFR throughout
the day and overnight hours into Thursday as well.
&&
.MARINE...A 990 mb surface low is moving into the region today
for increasing southerlies over much of the waters. A Gale Warning
remains in place with gusts exceeding 35 kts over all of the coastal
waters and East Entrance. A small craft advisory continues for the
Northern Interior Waters and Admiralty inlet for enhanced
southerlies with an additional SCA now going into effect later this
evening into Thursday morning for a westerly push through the
Strait. High pressure will redevelop on Thursday and into Friday,
bringing lighter winds and more benign marine conditions.
Coastal seas 9 to 11 ft this morning, falling to 6 to 8 ft tonight.
An additional swell train will arrive on Thursday keeping seas near
the 10 ft range before decreasing on Friday and into the weekend.
McMillian
&&
.HYDROLOGY...
No river flooding is expected over the next 7 days.
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Winter Weather Advisory until 11 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.
PZ...Small Craft Advisory from 8 PM this evening to 11 AM PDT
Thursday for Central U.S. Waters Strait Of Juan De Fuca-
East Entrance U.S. Waters Strait Of Juan De Fuca.
Gale Warning until 5 PM PDT this afternoon for East Entrance
U.S. Waters Strait Of Juan De Fuca.
Small Craft Advisory until 5 PM PDT this afternoon for
Admiralty Inlet-Northern Inland Waters Including The San
Juan Islands.
Gale Warning until 11 AM PDT this morning 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