High Wind Watch 10, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
346 AM AKST Mon Dec 18 2017

.DISCUSSION...
Main forecast highlight will the strong winter storm that has set
its sights on Western Alaska over the next 24 to 36 hours and over
Eastern Alaska starting Tuesday morning. There has been a slight
shift in the flow near the surface from southerly to southwesterly
with the recent model guidance, which will likely increase the of
precipitation/snowfall over the Middle Tanana Valley and the
Eastern Interior. The 18/00Z model guidance is in good agreement
through 06Z Wednesday, with differences in the details of the
individual lows over the Northern Pacific and Bering Sea in the
southwest flow through 00Z Friday, then significant differences
beyond 00Z Friday. Above normal temperatures across Northern
Alaska will continue through the forecast period with the coldest
temperatures entrenched over eastern Siberia.

Western Interior and West Coast...A strong 944 mb low over the
western Bering Sea and associated occluded front will move
northwest along the eastern Siberian Coast and over the Bering
Strait. The occluded front currently over Saint Lawrence Island
and the central Bering Sea will move east and onshore over the
Yukon Delta, Bering Strait, and western Seward Peninsula this
morning, then will proceed east and be over the Western Interior
by early Tuesday morning. A messy, winter event will ensue as the
front move east, bringing a combination of blizzard conditions
with southeast winds gusting to 60 to 70 mph along the immediate
West Coast including St Lawrence Island, a mix of freezing rain
and snow to the Yukon Delta and Lower Yukon Valley, and heavy
snow to the southwestern Brooks Range and southern Seward
Peninsula. Snowfall amounts will vary with the heaviest being in
favored upslope areas of the Brooks Range where there is a
potential for 12 to 25 inches. Elsewhere, there is the potential
to see 6 to 12 inches with up to 0.10" of ice accumulation for
zones 214 and 215. The main low will pass to the west of St.
Lawrence Island Tuesday afternoon, with a second strong low
approaching to the south of the island late Wednesday afternoon.
This will bring strong southerly winds approaching sustained in
the low end of storm force. The only change to the current winter
hazards was to the blizzard warning for zone 209, where the start
time was move up to 19/00Z since stronger winds are expected to
arrive earlier than previously anticipated.

Central and Eastern Interior...The aforementioned occluded front
will approach the central Interior by early Tuesday morning.
Moderate to heavy snow will spread east into western zones 218,
219, and 221 by early Tuesday morning and continue to slowly
spread east reaching the Middle Tanana Valley Tuesday afternoon,
and the Fortymile Country/Upper Tanana Valley by late Tuesday
evening. Winter Weather Advisories for zones 219 and 221 still
look good as 4 to 7 inches of snowfall is expected through
Wednesday afternoon. Added a Winter Storm Warning from the Dalton
Highway west in zone 218, where there is the potential to see 6 to
12 inches. May need to consider a potential winter weather
headline for zone 222, where slight changes in the flow have
increased the amount of snowfall from a few inches to 3 to 6
inches with heaviest amounts over the hills northeast of
Fairbanks through Wednesday afternoon. Could see gusty winds and
blowing snow over interior highway summits, but not expecting
reduced visibilities below one-half mile in blowing snow.

North Slope and Brooks Range...As the front moves north and west
tonight, east winds will increase from Barrow west along the
western Arctic coast with blowing snow and reduced visibility
developing. Have decided to issue a blizzard warning for zone 201
for tonight into tomorrow morning, where gusts up to 50 mph and
blizzard conditions are possible. Could see a couple of inches of
new snow with this front as well in zone 201. Light snow will
spread east along the coast tonight into Tuesday where around an
inch of new snowfall is expected. In the Brooks Range, will see
southerly gap winds ramp up this evening and continue through
Tuesday evening before weakening with winds peaking around 25 mph
gusting 40 mph. Will issue a winter weather advisory for zones
205 and 206 due to blowing snow and reduced visibility. Otherwise,
temperatures will slowly warm through Thursday where temperatures
will be 25 to 35 degrees above normal.

Coastal Hazard Potential Days 3 and 4...None.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning for AKZ208-AKZ210-AKZ211-AKZ212-AKZ214-
AKZ215-AKZ216-AKZ217-AKZ218.

Blizzard Warning for AKZ201-AKZ207-AKZ209-AKZ213.

Winter Weather Advisory for AKZ205-AKZ206-AKZ219-AKZ221.

Heavy Freezing Spray Warning for PKZ210-PKZ220.

Gale Warning for PKZ200-PKZ210-PKZ215-PKZ220-PKZ225.

Brisk Wind Advisory for PKZ230-PKZ235-PKZ240.
&&

LTH DEC 17