Gale Warning 4, NWS Seattle, WA

Area Forecast Discussion
National Weather Service Seattle WA
240 PM PST Sun Jan 9 2022

.SYNOPSIS...The brief sunny and dry period ends today. A return to
clouds and rain as a weak front moves through. With more rain
expected Tuesday into Wednesday as an atmospheric river impacts
the area. This Tuesday to Wednesday will cause area rivers to rise
with some reaching flood stage. Showers will linger Thursday
before we dry out again towards the end of the week.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...Things will remain dry
through the rest of Sunday, but clouds will be moving in ahead of
an approaching front late tonight. Southerly winds will begin to
pick up early Monday morning as the front approaches. Wind
advisories have been issued for the Coast as well as areas near
the Northern Inland waters. Breezy conditions expected for the
other areas of Western Washington. Rain from this approaching
front will move in during the morning. Rain will mostly be light
for the area, but coastal areas could see some moderate and brief
periods of heavy rain Monday. Snow levels will be rising above
5000 feet by the afternoon.

The more vigorous system will begin to impact the area Tuesday
and will continue into Wednesday. This system will bring
widespread heavy rain to the area. With 5-7 inches expected at the
coast during this time frame. The North Cascades will also get a
significant amount of rainfall with 3-5" likely in the North
Cascade region. The interior lowlands are expected to receive
significantly less with only 1-2 inches expected at this time.
This will be a rather warm system, and will mark the return to
lows in the 40s and highs in the 50s for the lowland areas of
Western Washington. With these warmer temperatures comes higher
snow levels. Snow levels will continue to rise above 6000 feet by
Wednesday. As a result, minimal snow is expected at pass level
during this event. Additionally, as this system moves through
expect winds to pick up, wind advisories are likely to be issued
in the coming forecast cycles for this atmospheric river event.
With rain and wind, we will once again see the threat of
landslides increase once more.

Butwin

.LONG TERM /THURSDAY THROUGH SUNDAY/...Showery conditions will
remain in place for the start of the long term period. For the
most part it looks as if we may see another break from the
onslaught of storms towards the end of the week. But with the
passage of disturbances we certainly could see some showers during
the weekend. The next wetter system still has uncertainty
associated with it but models have trended it to show up in
Western Washington later Sunday.

&&

.AVIATION...Aside from a few passing high clouds this afternoon,
mostly sunny skies rule W WA. The exception to this is the fog
across the South Sound impacting OLM and the development of some
MVFR clouds along the Northern Olympic Peninsula affecting CLM.
Expect conditions to improve at both sites in the next hour. Clear
conditions will carry over into the overnight period before clouds
quickly increase along and just ahead of the next front Monday
morning. VFR ceilings are expected as the rain passes thru,
eventually dropping to MVFR Monday afternoon. Winds E/SE under 10kts
(HQM 10-15kts)

KSEA...Clear conditions into much of the overnight period, with VFR
ceilings developing as light rain moves thru early Monday morning.
Scattered showers and MVFR ceilings expected by Monday afternoon.
Winds E/SE less than 10kts.

Kovacik

&&

.MARINE...High pressure at the surface and aloft will continue to
influence the local area into the overnight period before the next
frontal system slides by early Monday. SCA level winds will continue
across generally all waters except Puget Sound through this evening.
Some fog development will be possible from mid-evening through about
midnight before the better chance of increasing cloud cover is
expected. Latest hi-res model guidance has indicated an increase in
wind speeds overnight tonight and into Monday morning, enough to
warrant a Gale Watch for the northern interior waters and the coast.
Elsewhere, will stick with a SCA. Winds over the waters will likely
remain breezy through much of Monday.

Although expect winds to ease a bit Monday night, an atmospheric
river will impact the area Tuesday and Wednesday . This will bring
heavy rain and more wind to the waters. Winds may then remain breezy
into Thursday and Friday before the potential for another break in
the weather early into the weekend.

Swells will begin to increase to between 10-12 ft Monday afternoon
and evening and eventually towards 15 ft on Tuesday before gradually
easing during the latter half of the week.

Kovacik

&&

.HYDROLOGY...Flood warnings on the Chehalis at Grand Mound and
Porter remain in effect this afternoon. The river at both forecast
points has crested and continues to recede. The river is expected
to drop below flood stage at Porter by Monday afternoon, and will
be the last warning to end from this previous event.

An atmospheric river will impact the area Tuesday into Wednesday.
With widespread heavy rain expected, area rivers will rise. The
plume of moisture will be centered over the Olympics as well as
the North Cascades, with 5-7" and 3-5" of rain expected at each
area respectively. Snow levels will be rising to above 6000 feet
between now and Wednesday.

At this time a hydrologic outlook for the Skokomish River in
Mason County and the Bogachiel River in Clallam County has been
issued as these two rivers are already forecasted to flood.
Watches fore these rivers and others are likely to be issued in
the coming forecast cycles.

Butwin

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Wind Advisory from 3 AM to 4 PM PST Monday for Admiralty Inlet
     Area-San Juan County-Western Skagit County-Western Whatcom
     County.

     Wind Advisory from midnight tonight to 4 PM PST Monday for
     Central Coast-North Coast.

PZ...Gale Watch from midnight PST tonight through Monday afternoon
     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 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 Watch from late tonight through Monday afternoon for
     Admiralty Inlet-East Entrance U.S. Waters Strait Of Juan De
     Fuca-Northern Inland Waters Including The San Juan Islands.

     Small Craft Advisory until 3 AM PST Monday for East Entrance
     U.S. Waters Strait Of Juan De Fuca.

     Small Craft Advisory until 3 AM PST Monday for Admiralty Inlet-
     Northern Inland Waters Including The San Juan Islands.

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

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

     Small Craft Advisory from 3 AM to 4 PM PST Monday for Puget
     Sound and Hood Canal.

&&

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