Brier Weather Station
Latitude N 47° 46' 49" Longitude W 122° 16' 48" Elevation 341 ft
252
FXUS66 KSEW 291554
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
854 AM PDT Tue Sep 29 2026
.SYNOPSIS...A frontal system will move across Western Washington
this morning, bringing continued rain and breezy winds. High
pressure builds aloft over the Pacific Northwest Thursday and
Friday, with just a slight chance of precipitation. The upper
ridge further builds next weekend for drier, warmer conditions.
&&
.SHORT TERM /TODAY THROUGH THURSDAY/...A frontal system
continues to move across western Washington this morning. Rain
will slide southwards through this afternoon, with the heaviest
rainfall amounts remaining in the north and central Cascades.
South winds remaining breezy, mainly across Puget Sound into
this afternoon. The Wind Advisory has been cancelled for the San
Juan Islands and western Whatcom County as winds slowly ease in
these areas in the next couple hours. A westerly push through
the Strait of Juan de Fuca late today may keep winds elevated in
these areas. Winds subside elsewhere late today and tonight.
An upper ridge slowly begins to build over the Pacific Northwest
on Wednesday, resulting in drier conditions. Areas of stratus
and morning fog may occur Wednesday AM due with lingering low-
level moisture and light winds under the building high pressure.
Temperatures residual moisture at the surface. Temperatures
will be cooler than normal but gradually warmer Wednesday and
especially Thursday reaching back in the mid to upper 60s.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...Ensemble guidance
remains in fairly strong agreement that the flow aloft becomes
more zonal by Friday. This will at least open the door for some
light precipitation across the region, though the likelihood is
somewhat low for much in the way of significant precipitation.
After this, the pattern would likely favor a return of high
pressure and some light offshore flow. This could yield a
somewhat mild start to October, with temperatures into the lower
70s. Some uncertainty in the ensembles in regards to the return
of more onshore flow early next week, but overall, warmer and
drier conditions are expected during this period.
&&
.AVIATION...Strong westerly flow will persist aloft today and
into Wednesday as a frontal system moves across western
Washington. Surface winds reflect this strong flow aloft with
heightened speeds expected through this afternoon. The majority
of the sites will experience south to southwesterly winds with
speeds 10-15 kts with gusts between 25-30 kt at times. Winds at
HQM are a bit stronger, with speeds between 15-20 kts and gusts
30-35 kts at times. Overall, wind speeds will ease by this
evening as the front pulls away from the area and the wind
direction shifts to the north to northeast. Expect winds to
subside to 5-10 kts by 03Z with some locations going light and
variable overnight tonight.
There remains a wide variation in cigs across the terminals this
morning, though conditions are predominantly MVFR to IFR. Cigs
will continue to trend downward in rain as this frontal system
works its way through the area. While some terminals may improve
to high-end MVFR to low-end VFR this evening into early tonight,
lingering low-level moisture from this exiting front will likely
bring another round of widespread MVFR to IFR conditions to the
terminals overnight into Wednesday morning.
KSEA...MVFR ceilings at the terminal this morning. While a fair
amount of rain shadowing is occuring, precip still looks to
fill into the terminal between 18-21Z. Brief reductions to IFR
cigs remain possible as the rain moves in. Cigs will then recover
back to around 3000 ft by early tonight...but expect improvement
to be short-lived as low-level moisture will likely bring the return
of MVFR to IFR conditions overnight into Wednesday morning.
Southwesterly winds between 10-15 kt with gusts to 25 kt will ease
towards 5-10 kt this afternoon and switch to the north/northeast
around 00Z.
18/14
&&
.MARINE...Breezy winds will continue across the area waters
today as a front pushes through the region. Winds have, however,
started to ease across the Northern Inland Waters in the
front`s wake, so have transitioned the Gale Warning over to a
Small Craft Advisory this morning. Seas across the coastal
waters remain high enough to keep inherited SCA in place there
through this afternoon. Elsewhere, expect small craft strength
winds to continue through this afternoon.
Onshore flow will diminish by early Wednesday. As such, seas
also diminish quickly as the system gets further away from the
coastal waters with wave heights around 7 ft by this evening and
down further to 4-6 ft by midday Wednesday. Surface high
pressure building over the interior of British Columbia and weak
troughing just offshore will lead to some weak east/southeast
flow on Thursday. Thermally induced surface low pressure begins
to expand northward along the coast toward the weekend for
northerly or weak offshore flow across area waters.
18/14
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 5 AM PDT Wednesday for Central U.S.
Waters Strait Of Juan De Fuca-East Entrance U.S. Waters
Strait Of Juan De Fuca.
Small Craft Advisory until 5 PM PDT this afternoon for
Admiralty Inlet-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-Northern Inland Waters Including The
San Juan Islands-Puget Sound and Hood Canal.&&
$$
NWS SEW Office Area Forecast Discussion