000
FXUS66 KSEW 241648
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
848 AM PST Sun Jan 24 2021

.SYNOPSIS...A front will bring light rain today with low snow
levels. Another weather system will reach the West Coast Tuesday
night--with the heavier precipitation moving into California. The
snow level will be low through the week ahead for a chance of
spotty light snow at times in the lowlands.

&&

.SHORT TERM /TODAY THROUGH TUESDAY/...No updates this morning--a
few of the higher DOT cams have a skiff of snow on the ground, and
Whatcom county is getting a little bit of snow this morning, but
overall the weather is behaving and the lowlands are seeing a
chilly rain with the front today.

Scattered showers will linger over the area tonight through
Monday night as a weak upper trough gradually shifts across the
region. Snow levels will remain relatively low which means the
higher hills will continue to flirt with possible snow, especially
night and morning hours. Impactful accumulations are not expected
however due to the spotty nature of the precipitation.

An upper low and an associated frontal system will move into the
area Tuesday afternoon into Tuesday night but it will be a
glancing blow as the bulk of the associated precipitation will be
going south of the area. Snow levels will be lower with this
system with easterly low level flow more favorable for lowland
snow. Light QPF suggests only minor snow accumulations for the
lowlands however. This is backed up by the ensemble solutions
which generally show an average of a few tenths of an inch of snow
most locations.

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...A weak front will fall
apart over the area on Wednesday. Snow levels will be low,
especially in the morning but QPF will be light and lowland snow
accumulations, if any, should once again be minor.

A couple of additional upper troughs will swing through the area
Thursday through Saturday for a continued threat of lowland snow
at times. It`s hard to be much more specific with the details and
lowland snow potential this far out for now. Snow levels are
expected to inch up each day so maybe the lowland snow threat will
be diminishing by the weekend. Schneider

&&

&&

.AVIATION... Ceilings this morning generally range from IFR to MVFR
with widespread light rain. Rain will remain the dominate precip
type today, with the best chance for light snow at KBLI this
morning. Not much improvement in ceilings expected through the day,
with MVFR likely the dominate category. Rain will taper to showers
through the second half of the day, with conditions remaining
unsettled into Monday. Winds S thru the period 8-12kts.

KSEA...MVFR ceilings like thru the period, generally ranging from
1500-2500ft. Light rain tapering to showers this evening. Winds S 5-
10kt.

Kovacik

&&

.MARINE...The marine forecast remains on track this morning with no
changes planned. A weak front near the Coast this morning will
provide the primary focus for widespread light rain over the waters
through much of the day today. Gale force winds still expected over
the Outer Coastal Waters behind the front. Previous discussion is
included below:

A frontal system will dissipate over the area this
morning. Weak surface low later today dissipating Monday. Another
front will arrive Tuesday night and move inland south of the
area. Strong surface low moving by to the west and south
Wednesday. The low will weaken and move north over the coastal
waters Thursday.

Gale force winds over the outer coastal waters through tonight.
Gales possible again Tuesday. Small craft advisories for the
most of the remainder of the waters through tonight. Winds easing
Monday with small craft advisory winds possible again Tuesday.

Seas building to 15 to 20 feet over the coastal waters tonight
then easing to 13 or 14 feet Monday.

Kovacik/Felton


&&

.HYDROLOGY...River flooding is not expected for the next 7 days.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory from 1 AM to 6 PM 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.

     Gale Warning until 1 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.

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

     Small Craft Advisory until 6 PM 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 6 AM PST Monday for East Entrance
     U.S. Waters Strait Of Juan De Fuca-Northern Inland Waters
     Including The San Juan Islands.

     Small Craft Advisory from 1 PM this afternoon to 6 PM PST Monday
     for West Entrance U.S. Waters Strait Of Juan De Fuca.

     Small Craft Advisory from 6 PM this evening to 6 AM PST Monday
     for Central U.S. Waters Strait Of Juan De Fuca.

     Small Craft Advisory until 6 PM PST this evening for Admiralty
     Inlet.

&&

$$

www.weather.gov/seattle

NWS SEW Office Area Forecast Discussion

Discussion Script by Ken True at Saratoga Weather - WFO Script by SE Lincoln Weather