Winter Weather Advisory 76, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
342 PM AKDT Fri Apr 9 2021

.SYNOPSIS...
Unseasonably cold temperatures are expected again tonight over
much of northern Alaska, with several locations at risk for
breaking low temperature records. A warming trend in temperatures
will begin on Sunday. A weather system will bring strong winds,
snow and blowing snow to the Yukon Delta and St Lawrence Island on
Saturday. A second system will affect the much of the West Coast
and Western Interior Saturday night into Sunday bringing the
potential for heavy snow along with gusty winds and blowing snow.

&&

.DISCUSSION...
The 9/12 UTC model suite initialized the forecast well when
compared to observational data. The models are in good agreement
out through the weekend.

Aloft at 500 mb, a 506 dam low is in place just east of
Fairbanks. An upper level ridge stretches from Bristol Bay to the
Chukotsk Peninsula. 850 mb temperatures at Fairbanks have dropped
into the 30s below under the cold trough aloft which would be
chilly for January let alone April (as seen on the special 18 UTC
sounding we did this morning). The trough will continue to dig
south and east tonight and Saturday while the ridge pushes east
over western Alaska on Saturday. An upper level low deepens to 513
dam and pushes northeast into the Central Bering Sea Sunday. The
low will push east through the Bering Sea Saturday night and
Sunday. As the low pushes east, southerly flow will develop over
much of the forecast area on Sunday. Southerly flow looks to
persist over much of the forecast area for much of next week.

At the surface, much of northern Alaskas is under high pressure. A
996 mb low is in the Gulf of Alaska south of Yakutat. This low
will continue to slide south tonight, but the resulting pressure
gradient may bing gusty northwesterly winds to the southeast
Interior tonight. A 984 mb low will move into the western Bering
Sea tonight. A front associated with this low will begin to affect
the West Coast tonight. The low will push to the east Through
Sunday, reaching near Nunivak Island by Sunday afternoon. Sunday
night, the low will push north to St. Lawrence Island where weaken
in place through Monday.

Central and Eastern Interior...
Very cold temperatures are expected for tonight, with many
locations seeing lows in the negative 20s or 30s or even colder.
Some locations have the potential to break records. There will be
some issues with very cold wind chill values tonight, especially
in the Alaska Range. We will stat to see a warming trend in
temperatures will start beginning on Saturday night, with
temperatures pushing closer to seasonal normal values by Monday.
There is the potential for strong southerly gap winds in the
Alaska Range Sunday into Monday. We opted to issue a high wind
watch for the eastern Alaska Range in anticipation of these winds.

North Slope and Brooks Range...
Well below seasonal normal temperatures are expected tonight into
Saturday night. Both nights we expect to see low temperatures in
the 20s to 30s below. Gusty southeasterly winds will continue to
bring wind chill values around 50 below along the Beaufort Sea
Coast this evening. Winds along the coast will die down late this
evening as high pressure builds over the area. Gradual warming is
expected to begin on Sunday. Winds along the coast west of
Utqiagvik will begin to increase for Sunday night and Monday
bringing the potential for blowing snow.

West Coast and Western Interior... Winds will increase tonight as
a front pushes into the area. Strong winds, snow and blowing snow
is expected as the front arrives resulting in blizzard conditions
for St. Lawrence Island and potentially for the Yukon Delta as
well. A second front will push over the area Saturday night. This
will bring the potential for heavy snow to the West Coast (from
the Seward Peninsula south) as well as along the Yukon River (from
Ruby west). 5 to 10 inches of snow is expected from Saturday
evening through late Sunday night. We opted to upgrade the Winter
Storm Watch for zone 213 to a Blizzard Warning in anticipation of
the poor conditions on St. Lawrence Island. The watch for zone 214
was upgraded to a Winter Storm Warning. The Yukon Delta really
gets a one-two punch. Strong winds and Blowing snow will develop
tonight with the first front resulting in the potential for
blizzard conditions along the coast. Heavy snow will then move
into the Yukon Delta Saturday evening. Cold temperatures tonight
combined with increasing winds will result in wind chill values
around -40 along the Chukchi Sea Coast. Wind Chill Advisories have
been posted for 207, 209 and 210 from midnight tonight until noon
tomorrow.

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

Extended forecast for days 4 to 7...A pattern change early next
week will bring seasonal temperatures to much of the Central and
Eastern Interior with highs in the 30s and 40s, and lows in the
teens and 20s above.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
High Wind Watch for AKZ226.

Blizzard Warning for AKZ213.

Winter Storm Watch for AKZ211-AKZ215-AKZ216.

Wind Chill Advisory for AKZ203-AKZ204-AKZ207-AKZ209-AKZ210-
AKZ226.

Winter Weather Advisory for AKZ212.

Winter Storm Warning for AKZ214.

Gale Warning for PKZ210.

Brisk Wind Advisory for PKZ200-PKZ220.
&&

APR 21