Heavy Snow in Washington, January 2 to 4, 2022

Area Forecast Discussion
National Weather Service Seattle WA
906 AM PST Sun Jan 2 2022

.SYNOPSIS...A slow moving cold front will approach the area today
and move inland tonight into Monday morning. Next system moving
inland over Oregon Tuesday with Fraser river outflow winds
developing over Whatcom county. Next system moving up from the
southwest arriving Wednesday night into Thursday with the system
stalling over the area until Friday.

&&

.SHORT TERM /TODAY THROUGH TUESDAY/...Strong S/SE flow continues
this morning ahead of our next incoming frontal system. Highest
winds are north of Everett. The strong south flow has also
boosted temps with western Whatcom and San Juans in the mid 40s.
Elsewhere, like Seattle south, we're still in the 30s but should
see rises into the lower 40s this afternoon too. This should help
to melt some of the remaining lowland snow across the region. Heavy
snow is still forecast in the Cascades tonight and the Winter
Storm Warning remains in effect. 33

Previous discussion...Upper level trough digging south well off
the coast today. This is stalling the southern progression of the
cold front northwest of the area. The cold front is pivoting from
an west of east orientation to a more north south orientation by
later this afternoon. This action will result in little southern
movement of the front during the day slowing down the onset of
precipitation over the area especially the interior. This stalling
of the front will also keep the very windy conditions going in
the Northwest Interior as well as the Admiralty Inlet area,
northern portion of Hood Canal and along the coast. For the
remainder of the area, winds will increase this afternoon as the
front creeps closer.

Cold front slowly moving inland tonight. Heavy snow in the
mountains with 1 to 2 feet possible into Monday morning. Snow
levels will be below the passes. The slow movement of the front
will keep the high winds going into the early morning hours over
the Northwest Interior, Admiralty Inlet and the northern portion
of the Hood Canal. Winds will also increase over the remainder of
the interior but at this time look to stay below advisory
criteria.

Cold front moving south of the area Monday morning. Cool unstable
air mass moving over Western Washington. Snow levels dropping to
around 1000 feet give or take a couple hundred feet. Heavier
showers could briefly push the snow level down to the surface but
no accumulations in the lowlands. Higher hills around the area
could see some snow accumulations in the morning hours but with
high temperatures near 40 degrees Monday afternoon the snow will
not stick around long. Thunderstorms possible along the coast with
the unstable air mass.

Snow levels lowering to 500-1000 feet Monday night as the cool
upper level trough remains over the area. Moisture will be
decreasing overnight. Once again heavier showers could briefly
pull the snow level down lower but no significant snow
accumulations are expected.

Next system moving inland over Oregon later Tuesday with most of
the moisture south of the area. Fraser river outflow winds picking
up during the day with the Bellingham to Williams Lake gradient
decreasing down to near -15 mb. High Tuesday once again near 40
with a little cooler temperatures over Whatcom county.

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...Models in good agreement
with a little break in the action Wednesday before the next
system moving up from the southwest reaches the area Wednesday
night into Thursday. This is a troublesome track with the
possibility of a strong overrunning snow event in Whatcom and
Skagit county later Wednesday night into Thursday. South of Skagit
county the warmer air aloft will scour out any colder air mass
remaining making the precipitation type rain in the lowlands.
Fraser river outflow winds coming to an end later Thursday with
the air mass over Whatcom and Skagit county quickly warming up.
System stalling over Western Washington Thursday night. Heavy
snow likely in the Cascades with the snow levels possibly rising
over pass levels. With easterly gradients in the passes keeping
cold air at the pass surface this could lead to a freezing rain
event in the passes later Thursday into Thursday night. Surface
gradients turning onshore Friday as the front finally moves out of
the area. Daytime temperatures warming into the mid 40s.
Unsettled weather continuing into Saturday. Felton

&&

.AVIATION...Southerly winds will be increasing throughout the
day as a cold front slowly approaches. Clouds will continue to
lower throughout the day with widespread MVFR expected by this mid
morning. Rain will move in this afternoon, and with combined with
winds visibility is expected to drop down during the heaviest
showers. Winds will ease through the overnight and into Monday.

KSEA...Ceilings will continue to lower this morning and into the
afternoon. Southerly winds will continue to increase throughout
the day, gusts 20-25 are likely starting around 0000 UTC. Rain
will also be moving in as these winds pick up. Visibility will
likely drop to 3-5 SM. Rain and winds will ease late Sunday and
into Monday

Butwin

&&

.MARINE...Southerly winds will continue to increase over all the
area waters into this afternoon. Gale warnings are up for the
for all the waters with the except of the Central Strait of Juan
de Fuca through tonight. Winds easing Monday as front moves south
of the area. Next system moving inland south of the waters
Tuesday. Small craft advisory winds expected towards the end of
the week with a system moving into the area from the southwest
Thursday into Friday.

Felton

&&

.HYDROLOGY...Transition to warmer, wetter pattern late in the
week could result in the Skokomish River in Mason County going
over flood stage. Outside of the Skokomish, river flooding not
expected in the next 7 days, but significant rises may also push
some points on the Chehalis and Newaukum River close to flood
stage.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Winter Storm Warning from 4 PM this afternoon to 4 PM PST Monday
     for Cascades of Pierce and Lewis Counties-Cascades of
     Snohomish and King Counties-Cascades of Whatcom and Skagit
     Counties.

     High Wind Warning until 4 AM PST Monday for Admiralty Inlet Area-
     Hood Canal Area-San Juan County-Western Skagit County-
     Western Whatcom County.

     Coastal Flood Advisory until 3 PM PST this afternoon for
     Admiralty Inlet Area-Central Coast-Eastern Strait of Juan
     de Fuca-North Coast-San Juan County-Western Skagit County-
     Western Whatcom County.

     Wind Advisory until 1 AM PST Monday for Central Coast.

     Wind Advisory until 4 PM PST this afternoon for Western Strait
     of Juan De Fuca.

     Winter Storm Warning until 4 AM PST Monday for Olympics.

     Wind Advisory until 6 PM PST this evening for North Coast.

PZ...Small Craft Advisory until 4 AM PST Monday for Grays Harbor Bar.

     Gale Warning until midnight PST tonight 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.

     Gale Warning until 4 AM PST Monday 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.

     Gale Warning until 2 PM PST this afternoon for West Entrance
     U.S. Waters Strait Of Juan De Fuca.

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

&&

www.weather.gov/seattle