Gale Warning 165, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
1157 AM AKST Mon Dec 19 2022

.SYNOPSIS...
Persistent high pressure remains situated over the mainland Alaska
with below normal temperatures across the Interior. An area of
particularly higher pressure situated over the ALCAN border is
helping to produce increased southeasterly winds in the Eastern
Alaska Range, which is causing cold wind chills for the area. As a
result, a Wind Chill Advisory is currently in effect for this
area. Southeasterly flow along the West Coast is allowing for
slightly warmer temperatures from Nome south along the coast. In
addition, some valley fog can be seen across the Interior this
morning.

&&

.DISCUSSION...
Aloft...
A strong upper-level ridge is currently situated in the Chukchi
Sea, with strong north-northeasterly flow on the east side of the
ridge assisting to funnel colder temperatures into the Interior,
as well as the absence of cloud cover to allow further cooling. A
small low pressure system situated over southcentral Alaska is
also helping to pull colder temperatures from the Yukon Territory
into the southeastern Interior, as well as pinching the pressure
gradient along the Eastern Alaska Range and allowing the formation
of increased southeasterly winds currently being observed in the
Deltana and Tanana Flats. This small area of low pressure will
undercut the ridge, effectively cutting off the strong high
pressure in the Chukchi Sea. As this low moves west-southwesterly,
a boundary stretching from the Yukon Delta to Yakutat will
inhibit a low pressure system in the Bering Sea from pushing
precipitation into the forecast area on Wednesday. A shortwave
riding long the east side of the high pressure in the Chukchi Sea
will dip southward into the eastern Arctic Coast and fizzle out
over the eastern Brooks Range on Thursday.

Surface...
At the surface, there isn't any major pattern changes for the next
few days. Dominant surface high pressure is currently being
observed over the mainland Alaska, with an area of particularly
strong pressure over the ALCAN border near Northway. This high
pressure is assisting with the pinched pressure gradient over the
Eastern Alaska Range that's supplying increased southeasterly
winds in the Deltana and Tanana Flats in addition to the below
normal temperatures, causing cold wind chills in the area.

North Slope and Brooks Range...
Light snow is currently being observed along the eastern Arctic
Coast, with below normal temperatures spanning across the region.
A small shortwave moving southward across the eastern Arctic Coast
will push into the eastern Brooks Range this evening, and
localized lift across the north side of the eastern Brooks Range
may help to produce light snow for this area through early Tuesday
morning. High pressure from the north dipping southward into the
North Slope will help to cut off any precipitation by Tuesday mid-
morning. A low pressure system developing in the Beaufort Sea will
slide southward into the Arctic Coast late Wednesday evening, and
is currently trending to bring light snow across the eastern
Arctic Coast and north side of the eastern Brooks Range Thursday
morning.

West Coast and Western Interior...
A strong mid-level ridge over the West Coast is producing
southeasterly flow that's causing warmer temperatures of single
digits/teens above from Nome southward along the West Coast. A low
pressure system moving in from the east will bring colder
temperatures for this area, dropping them to the single digits
above/below by tonight. Another low pressure system to the south
of the region will try to push precipitation into the Yukon Delta
and Lower Kuskokwim Valley, but high pressure to the north will
likely keep the chances for precipitation low on Thursday.

Central and Eastern Interior...
A dominant area of high pressure situated over the ALCAN border is
supplying significantly below normal temperatures across the
region, as well as increased southeasterly winds for the Deltana
and Tanana Flats. As a result, a Wind Chill Advisory is in effect
for this area. The pattern for this region remains pretty
stagnant, with this high pressure inhibiting precipitation and
supplying continuous below normal temperatures for the next few
days.

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

Extended Days 4 Through 7...
Medium- and long-range models begin to vary quite a bit after
Thursday, where some hint at another blast of cold air from the
Yukon Territory on Saturday. Hints of a low pressure system in the
Gulf of Alaska Monday morning may bring some precipitation into
the southeastern Interior, but any amounts and intensity of
precipitation, as well as timing and placement, varies greatly.
This system appears to be the next chance for snow in the
Interior.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Wind Chill Advisory for AKZ223.
PK...Brisk Wind Advisory for PKZ201.
     Small Craft Advisory for PKZ210.
     Heavy Freezing Spray Warning for PKZ210.
&&

KL