803
FXUS66 KSEW 030355
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
755 PM PST Fri Jan 2 2026
.SYNOPSIS...
Active weather pattern for the next week. A stronger
frontal system will move through later Saturday into Sunday for
increasing winds. A break break in the steady precipitation is
possible Monday. Another system is likely Tuesday into Wednesday
for lowland rain, breezy winds, and heavy mountain snow. A
coastal flooding threat exists into early next week.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
Inherited forecast remains on track for the evening update. HPR
Precipitation will continue to slide northwards tonight into
Saturday morning. Lowland rain at times. Snow levels will remain
near 5500 to 7000 feet into Saturday morning, but light east
flow at the Cascade Passes may result in brief freezing rain at
times for Stevens Pass. A stronger system will move through
Saturday into Sunday, coinciding with higher astronomical tides.
The main hazards this weekend will be coastal flooding and
wind, which have been discussed briefly below.
Coastal Flooding: Abnormally high astronomical tides will result
in an increased risk of coastal flooding through early next
week. Coastal Flood Advisories have been issued for a majority
of the interior waters during high tide on Saturday morning with
minor coastal flooding forecast. A Coastal Flood Warning has
been issued for the coast due to higher water levels,
potentially approaching 3 feet above ground level during high
tide. Water levels will likely peak on Sunday as high tides will
coincide with lower pressure associated with a storm system
tracking offshore. Breezy south winds will also occur Sunday AM
during high tide. For this reason, Coastal Flood Watches have
been issued for the coast, San Juan Islands, and western Whatcom
County. Building seas offshore (to near 12 to 15 feet) will
also exacerbate coastal flooding concerns along the coast.
Additional headlines (Coastal Flood Advisories) will be
monitored for elsewhere on Sunday due to expected minor coastal
flooding. During high tides over the weekend, roads may be
closed due to coastal flooding, some low-lying areas may be
inundated, and shoreline erosion or damage may occur.
Wind: South winds will increase late tonight through Saturday
morning, with the strongest winds along the immediate coast, and
Hood Canal northwards. Wind gusts in these areas are expected to
range 25 to 40 MPH, with isolated higher gusts to 45 MPH.
Elsewhere, gusts will peak between 15 to 30 MPH. A compact low
pressure system will move northwards offshore Saturday into
early Sunday, resulting in another round of breezy conditions
Sunday morning. There remains some uncertainty into the exact
magnitude of winds Sunday AM.. at this time, wind gusts are
expected to range 25 to 40 MPH, with gusts to near 45 MPH along
the coast and north of Hood Canal. However, winds could be
locally stronger depending on the storm track, with the 90 PCT
wind gusts on Sunday from NBM peaking in the 50-55 MPH range
for the coast and north interior. Will continue to monitor this
period for potential headlines.
Snow levels will generally range 4000 to 5000 feet Saturday into
Sunday, resulting in higher elevation mountain snowfall. Snow
levels will then lower to 3500 feet by Sunday night.
Temperatures will warm into the low to mid 50s on Saturday,
becoming a few degrees cooler Sunday.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
A brief break in the steadier precipitation is likely on
Monday, with a few lingering showers, and light snowfall amounts
in the Cascades. Ensembles are consistent in another stronger
frontal system dropping southwards out of British Columbia
Tuesday afternoon through Tuesday night. Steadier lowland rain
is likely with the front. In addition, there is increasing
confidence for heavy mountain snowfall, including for the
Passes, Tuesday through Wednesday. The probability for over 12
inches of snow from Tuesday- Wednesday currently ranges 80 to 90
percent for Stevens and Snoqualmie Pass. For those traveling
over the Passes, continue to monitor the forecast and be aware
of potential heavy snow. In addition to lowland rain and
mountain snow, another round of gusty winds are expected.
Probabilities (from NBM) of wind gusts over 45 MPH range between
25 to 45 percent along the coast and Whidbey Island northwards
on Tuesday, with lesser probabilities elsewhere. A cooler, post-
frontal airmass will settle into Western Washington midweek,
with continued shower potential late Wednesday into Thursday.
Upper ridging may try to develop over Western Washington by
Friday. JD
&&
.AVIATION...
Low ceilings continue this evening, ranging from MVFR to LIFR,
with limited visibility ranging from 1SM-4SM due to light rain
and/or drizzle. Conditions have marginally improved in spots to
MVFR this evening, however conditions will likely struggle to
improve and remain IFR/LIFR as another system is expected this
evening. Winds are E/SE this evening. Southerly winds will
increase Saturday morning continuing through the afternoon.
There is the potential for 20 kt gusts (40-80%), with the
highest chances along the coast, southern interior, and Kitsap
Peninsula. Gusts to 25 kt possible (60-80%) for terminals north
of BFI.
KSEA...Rain will continue over the terminal through much of the
TAF period. Ceilings temporarily improved to MVFR this evening
with the rain, however visibilities may lower down to IFR at
times with the rain/mist mix. IFR ceilings remain likely to
settle back in tonight/Saturday morning before improving
substantially to VFR late Saturday. Light SE winds tonight at
5-10 kt. Southerly winds will increase Saturday morning to 6-8
kt. In addition, there`s a 40-50% chance of 20 kt gusts. 29/HPR
&&
.MARINE...
Easterly flow over the waters today with low pressure
offshore and high pressure east of the Cascades. A system will
move over area waters today into Saturday morning. A stronger
frontal system will move through the waters Saturday evening
into Sunday. Guidance hints at a brief break on Monday, before
additional systems move through the waters later in the week.
The system moving in today into Saturday morning will be weaker than
the later on Saturday, but will bring Small Craft conditions (winds
and waves) to area waters, with the exception of the Central Strait.
As for the stronger system Saturday evening, there is the potential
for gale winds for area waters (except the Central Strait), for
which a Gale Watch has been issued.
Seas 5 to 8 feet will build to 10 to 13 feet by late Saturday
morning and hovering through the weekend. Seas will subside below 10
feet on Monday before possibly building to 13 to 18 feet on
Wednesday. 29
&&
.HYDROLOGY...
Multiple frontal systems will move through Western
Washington into next week. The Skokomish River is forecast to
rise on Sunday, but currently expected to remain below flood
stage. The river will slowly recede Monday into Tuesday, before
rising again midweek and approach flood stage Wednesday. No
additional river flooding is expected the next 7 days.
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Coastal Flood Advisory from 5 AM to 9 AM PST Saturday for
Lowlands of Western Whatcom County-San Juan County.
Coastal Flood Watch Sunday morning for Lowlands of Western
Whatcom County-San Juan County.
Coastal Flood Advisory from 4 AM to 8 AM PST Saturday for City
of Seattle-Downtown Everett / Marysville Area-Island
County-Lowlands of Pierce and Southern King Counties-
Lowlands of Western Skagit and Northwestern Snohomish
Counties-Shoreline / Lynnwood / South Everett Area.
Coastal Flood Advisory from 10 AM to 2 PM PST Saturday for
Eastern Strait of Juan de Fuca-Western Strait of Juan de
Fuca.
Coastal Flood Warning from 10 AM to 2 PM PST Saturday for
Grays Harbor County Coast-Northern Washington Coast.
Coastal Flood Watch from Sunday morning through Sunday
afternoon for Grays Harbor County Coast-Northern
Washington Coast.
PZ...Small Craft Advisory from 6 AM Saturday to midnight PST
Saturday night for Grays Harbor Bar.
Small Craft Advisory until 6 PM PST Saturday for West Entrance
U.S. Waters Strait Of Juan De Fuca.
Gale Watch from Saturday evening through Sunday 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-West
Entrance U.S. Waters Strait Of Juan De Fuca.
Small Craft Advisory from 4 AM Saturday to midnight PST
Saturday night for Admiralty Inlet-East Entrance U.S.
Waters Strait Of Juan De Fuca-Northern Inland Waters
Including The San Juan Islands.
Gale Watch from late Saturday night through Sunday morning for
Admiralty Inlet-East Entrance U.S. Waters Strait Of Juan
De Fuca-Northern Inland Waters Including The San Juan
Islands-Puget Sound and Hood Canal.
Small Craft Advisory from 8 AM Saturday to midnight PST
Saturday night for Puget Sound and Hood Canal.
Small Craft Advisory until 6 PM PST Saturday for Coastal
Waters From Cape Flattery To James Island Out 10 Nm-
Coastal Waters From James Island To Point Grenville Out
10 Nm-Coastal Waters From Point Grenville To Cape
Shoalwater Out 10 Nm.
Small Craft Advisory until 6 PM PST Saturday for Coastal
Waters From Cape Flattery To James Island 10 To 60 Nm-
Coastal Waters From James Island To Point Grenville 10 To
60 Nm-Coastal Waters From Point Grenville To Cape
Shoalwater 10 To 60 Nm.
&&
$$
NWS SEW Office Area Forecast Discussion