Gale Watch 54, NWS Seattle, WA

Area Forecast Discussion
National Weather Service Seattle WA
241 PM PST Fri Nov 26 2021

.SYNOPSIS...A wet warm system will be moving into the area late
tonight/early Saturday morning. Widespread rain will be heavy at
times and will continue through Sunday. Things will remain
unsettled on Monday. The next frontal system is expected to move
through Tuesday into Wednesday. Another break between weather
systems is expected for the second half of the week.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY/...An atmospheric river
continues to approach the area through the rest of the day. As
this system approaches during the morning hours winds will become
breezy, particularly in for areas near the Northern Inland waters.
In addition to some breeziness we are expecting widespread heavy
rain with high snow levels. The North Coast, Olympics as well as
the Central and Northern Cascades are expected to see the highest
rainfall totals. These aforementioned areas are expected to
receive 3-6 inches through the weekend. For the lowlands and more
southern portions of the area total rainfall amounts will be
closer to 1-2 inch range. Area rivers are expected to rise, with
some going above flood stage (See hydrology section below for
more details). There could be some water ponding during throughout
the area, particularly during periods of heavier rain. Those
driving should give themselves extra time and not drive through
flooded road ways. As the rain falls, the threat of landslides is
going to increase.

Things are expected to quiet down Monday as rain showers will
continue to scatter out as well as a weak shortwave disturbance
moves through the area. All area rivers are expected to be
receding by late Monday.

Throughout the short term temperatures will be warm with highs
in 50s and lows in the mid 40s to low 50s.

Butwin

.LONG TERM /TUESDAY THROUGH FRIDAY/...Another frontal system is
expected to move through the area later Tuesday into Wednesday.
While this system is another warm one, the bulk of the moisture
is expected to be well to the north of Western Washington. After
Wednesday things will be mostly dry at least for a few days. With
slightly more seasonable temperatures.

Butwin

&&

.AVIATION...A brief period of dry conditions is expected this
afternoon and into tonight before the next frontal system brings
another round of precipitation into W WA Saturday morning. Flow
aloft will remain generally westerly today and into Saturday.

Cigs remain a mixed bag this afternoon with a mix of VFR /mainly
along the coast/, MVFR and IFR conditions present /inland/. Current
TAFs might be a little optimistic as current conditions show little
expectation for any improvement over the area. Will alter those
accordingly with 00Z update. One batch of clouds will lead to
another as those associated with the next frontal system already
starting to move over the NW corner of the state again nullifying
any prospects for improvement. Rain starting Saturday morning will
make for widespread MVFR to IFR conditions. Surface winds expected
to remain South to Southwesterly 5-10 kts this afternoon before
easing to generally light and variable 5 kts or less into the
overnight hours. Should see a shift to more easterly winds come
Saturday morning.

KSEA...MVFR conditions in place and expected to continue for the TAF
period. Cigs dipping down into low-end MVFR early Saturday morning.
Winds will be southerly 4-8 kts, becoming light and transitioning to
the north and east late tonight. 18

&&

.MARINE...Winds will remain benign across the area waters today,
before another frontal system system moves across the region
Saturday and Sunday. This system will likely yield another round of
Small Craft Advisories for most area waters with a brief period of
gales possible across portions of the Coastal Waters and Northern
Inland Waters. As such, have gone ahead and decided on Gale Watches
for these locations with Small Craft Advisories leading up to the
aforementioned watches. SCAs also up for waters adjacent from those
under Gale Watches. Additional systems will progress through the
region early next week, likely yielding additional headlines for the
area waters.

Westerly swells gradually subsiding to near 8 to 10 feet tonight.
This will allow SCA for rough bar/haz seas to expire. Swells will
remain under 10 feet through Saturday, before gradually increasing
to near 10 feet again on Sunday. 18

&&

.HYDROLOGY...A wet and warm frontal system will affect the area
later Saturday through Sunday. This will bring a renewed threat
for river flooding, especially for rivers flowing out of the
Olympics and the central and northern Cascades. A flood watch has
been issued. Most river flooding that does occur is expected to
be minor although a few rivers could see moderate flooding and the
Skagit River might see a brief period of major flooding.

A second frontal system will potentially affect the region
Tuesday into Wednesday although confidence is lower with this
system. Ensembles suggest the most likely scenario is for this
evening to be less impactful with the bulk of the moisture aimed
north of the area. 16

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Flood Watch through Sunday afternoon for Bellevue and Vicinity-
     Cascades of Snohomish and King Counties-Cascades of Whatcom
     and Skagit Counties-East Puget Sound Lowlands-Everett and
     Vicinity-Seattle and Vicinity-Western Skagit County-Western
     Whatcom County.

     Flood Watch through Monday evening for Hood Canal Area-Lower
     Chehalis Valley Area-Olympics.

     Flood Watch from Saturday evening through Monday evening for
     Admiralty Inlet Area-Central Coast-Eastern Strait of Juan
     de Fuca-North Coast-Western Strait of Juan De Fuca.

PZ...Small Craft Advisory until 6 PM PST this evening for Grays
     Harbor Bar.

     Gale Watch from Saturday morning through Saturday 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-East Entrance U.S.
     Waters Strait Of Juan De Fuca-Northern Inland Waters
     Including The San Juan Islands.

     Small Craft Advisory until 10 AM PST Saturday 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.

     Small Craft Advisory from 4 AM to 10 AM PST Saturday for East
     Entrance U.S. Waters Strait Of Juan De Fuca-Northern Inland
     Waters Including The San Juan Islands.

     Small Craft Advisory until 4 PM PST this afternoon for West
     Entrance U.S. Waters Strait Of Juan De Fuca.

     Small Craft Advisory from 4 AM Saturday to 4 AM PST Sunday for
     West Entrance U.S. Waters Strait Of Juan De Fuca.

     Small Craft Advisory from 10 AM to 7 PM PST Saturday for Central
     U.S. Waters Strait Of Juan De Fuca.

     Small Craft Advisory from 4 AM Saturday to 10 AM PST Sunday for
     Admiralty Inlet.

&&

www.weather.gov/seattle