349
FXUS66 KSEW 161717
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
917 AM PST Sun Nov 16 2025

.SYNOPSIS...
A frontal system will slowly move across Western
Washington through Monday for unsettled weather. An upper low
moves eastwards on Tuesday for a brief period of drier weather
late Tuesday into Wednesday. A trough will approach the Pacific
Northwest on Thursday, with another frontal system possible next
weekend.

&&

.UPDATE...
Visibilities are on the rise across much of the Puget Sound
area. Will allow the dense fog advisory expire at 10 am, but a
few areas may see low visibilities at times (especially as an
inversion keeps low level moisture trapped, keeping areas misty
at times throughout the day). Showers remain on track to pass
through at times today, but otherwise there are no major changes
to the discussion below.

HPR

&&

.SHORT TERM /TODAY THROUGH TUESDAY/...
Widespread low stratus across Western Washington this morning
with light flow and abundant moisture at the surface. Areas of
fog have also developed, especially in sheltered locations.
Light north winds around Puget Sound will become calm for a few
hours this morning, allowing for the potential of more
widespread dense fog, mainly between 300-900 AM. This will
continue to be monitored for any dense fog headlines.

Otherwise, a weak front will move across the area late today
into Monday for light rain at times. An upper low will also
become cutoff from the elongated trough over the Western US. The
upper low will slowly progress overhead across Western
Washington and southern British Columbia late Monday into early
Tuesday for additional precipitation chances. QPF totals through
Tuesday afternoon look to range from 0.10 to 0.50" for the
lowlands, with the highest values from King CO northwards. Snow
levels around 7000 feet today will lower to 4000 feet late
Monday into Tuesday for light snowfall amounts in higher
elevations. Temperatures will slowly cool a dew degrees each day
through Tuesday, with highs near normal in the low 50s by
Tuesday.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
A brief period of drier weather is expected late Tuesday into
Wednesday as transient upper ridging builds into the Pacific
Northwest. Troughing will then approach the west coast Wednesday
night into Thursday. Ensembles suggest the troughing is
elongated on Thursday with the majority of energy steered
towards OR/CA. However, precipitation potential will increase
again beginning Wednesday night. In addition, east winds look to
increase near the Cascade Foothills Wednesday night as well
with the incoming system. Uncertainty increases in ensembles
Friday into next weekend, however the upper level pattern
supports more zonal flow at this time, resulting in a period of
potential heavier precipitation. Temperatures are expected to
remain near normal for much of the week, with highs in the low
to mid 50s. JD

&&

.AVIATION...
Southwesterly flow aloft becoming southerly overnight as
weakening front moves into the area.

LIFR ceilings and visibilities along the I-5 corridor between
KPAE and KTCM will lift by 21z to MVFR ceilings and
visibilities. For the remainder of the area outside the I-5
corridor from Everett south LIFR/IFR ceilings lifting to MVFR
21z-00z. North of Everett a mix of MVFR and low end VFR
ceilings into Monday morning.

KSEA...Visibility in the 3-5sm range with ceilings bouncing
between MVFR and IFR through this evening. IFR ceilings and
visibilities in rain after 06z into Monday morning. Southeast
wind 4 to 8 knots becoming southerly tonight. Felton

&&

.MARINE...
A surface low will track into Northern Vancouver
Island today into tonight while an associated front weakens and
moves onshore. Here, a westerly push is expected through the
Strait of Juan de Fuca with SCA winds a possibility overnight
into Monday morning. A surface ridge will rebuild across the
waters Monday into Tuesday before shifting east of the area on
Wednesday. A rapidly weakening frontal system will reach the
waters Wednesday night into Thursday with the potential for more
headlines, but mainly over the coastal waters.

Coastal seas will briefly build to 10 feet or higher Sunday
afternoon into Sunday night as a SCA remains for the coastal
zones. Seas will then subside below 10 ft Monday night into
Tuesday. However, 10 ft seas will likely return around midweek.

McMillian

&&

.HYDROLOGY...
A weak frontal system will produce non-
hydrologically significant rainfall late today into Tuesday.
Drier conditions will return mid-week. Another system will
bring additional precipitation late Wednesday into Thursday, but
is again not expected to produce rainfall of any significance.
Additional weather systems are possible Friday into next
weekend. 27/JD

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Dense Fog Advisory until 10 AM PST this morning for City of
     Seattle-Eastside-Lowlands of Pierce and Southern King
     Counties-Olympia and Southern Puget Sound-Shoreline /
     Lynnwood / South Everett Area.

PZ...Small Craft Advisory from 4 PM this afternoon to 7 AM PST
     Monday 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 10 AM PST Monday 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.

&&

$$