Gale Warning 59, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
242 PM AKST Fri Feb 9 2024

.DISCUSSION...

.SYNOPSIS...

Active weather pattern continues into this weekend along the West
Coast of Alaska and in the Interior mountain passes. While, ridging
and southerly flow aloft bring warmer temperatures, expect high winds
gusting 60 to 70 mph through Alaska Range Passes through late Saturday
evening, potentially persisting into Sunday morning. High Wind
Warnings are currently effect for the Alaska range passes. With
low pressure over the West Coast and high pressure over the Yukon
Territory, northeast winds over Dalton Highway Summits may cause
areas of blowing snow and significantly reduced visibility today.
Winds over Eagle Summit are expected to be quite strong on
Saturday night and Sunday and blowing snow may cause significant
reductions in visibility there as well. Winter Weather Advisories
are in effect for both areas. Strong upper ridging building in
aloft into early next week will lead to a warm and dry pattern for
the interior, but keep the active weather ongoing for the West
Coast. Multiple rounds of precipitation and potentially high winds
will continue for the West Coast and far Western Interior this
weekend into mid next week. P-type issues with mixed precip and
rain become a concern for this region early next week as much as
much warmer air surges north.

.DISCUSSION...

Analysis and Model Discussion...

A SE to NW oriented upper ridge extends from NW Canada into
Northern Alaska, while troughing persists over the Bering and
across the West Coast of Alaska. Mid and upper level southerly
flow significantly increase across much of the state today within
a strong baroclinic zone between west coast troughing and ridging
further east. Tightening pressure gradient in addition to strong
winds aloft will lead to an extended period of high winds through
mountain passes of the Alaska Range and a blowing snow threat
within the White Mountains and through the passes along the Dalton
Hwy. Downsloping winds and a much warmer airmass surging
northward will result in temperatures well above normal for this
time of year. 850mb temperatures range from -2 C over the Lower
Yukon Valley to -10 C over the Alcan Border and over the North
Slope. Temperatures aloft will follow a warming trend through
Saturday, then a brief period of cooler air Sunday as cold air is
wrapped around a low pushing north through the Bering Strait.

At the surface, a 969mb low slowly pushes northward into Bristol
Bay while high pressure sits over the Yukon and NE Alaska. The
low will slowly weaken and move north to near Anvik at 980 mb by
late Saturday afternoon, spreading snow from the Yukon Delta north
to Point Lay by that time. The low continues to slowly weaken and
head northward toward Point Hope by Sunday morning.

Latest 09/12z model suite is in good agreement, with the GFS
coming more in line with the EC and Canadian in the most recent
runs.

Central and Eastern Interior...

Main area of focus for the Interior will be the high wind threat
through Alaska Range passes and blowing snow threat further
north through the interior summits and passes along the Dalton
Hwy today through Sunday. Surface high pressure over the Yukon
will push strong Tanana Valley Jet winds through Delta Junction
through Saturday night. Relatively high pressure building over
the Copper Basin in conjunction with the shortwave aloft will also
result in strong south winds gusting 60 to 70 mph through Alaska
Range Passes during this time frame. Confidence is increasing in
gusts along the Parks Hwy to increase to 70 mph Saturday
afternoon, therefore will upgrade the Advisory to a High Wind
Warning for that area. Current High Wind Warnings are in effect
through 09z Sunday, however potential is there for high winds to
persist into early Sunday morning as well. Also watching for
strong SW winds to potentially set up Saturday into Saturday night
along the Alcan from Dot lake to Tanacross. Adding that to the
forecast but confidence is only marginal in strong winds there.
Strongest winds for the Alaska range are expected late tonight
into the day on Saturday, slowly dropping off Sunday morning.
Winds at Delta Junction may begin to diminish a bit earlier as
the Tanana Valley Jet weakens and winds turn southerly. Dalton
Highway Summit winds will be the strongest through Friday evening
as a shortwave passes by. The Steese Highway Summits, White
Mountains and higher terrain south of the Yukon River will
continue to see winds increasing this evening and peak on Sunday
before weakening thereafter. The worst conditions are expected
near Eagle Summit on Sunday morning with areas of blowing snow
reducing visibility to one half mile or less at times.

Temperatures in windy and downsloped areas have already exceeded
guidance with numerous observations already above freezing around
the Alaska range. Expect these warmer temperatures to persist
through the weekend as well. Highs elsewhere will be mostly in
the teens and 20s through the weekend. A weak shortwave will bring
less than an inch of snow north of Livengood today. Fairbanks has
a slight chance of seeing some flurries this afternoon as this
shortwave passes over, however no accumulation is expected.

North Slope and Brooks Range...

Northeasterly gradient from high pressure over the Yukon and a
deep low near Bristol Bay will result in NE winds over Dalton
Highway summits, where a Winter Weather Advisory for blowing snow
and low visibility is in effect through Saturday night. East
winds of 20 to 30 mph continue along the arctic coast this evening
and are expected to persist into Saturday. Expect east winds to
slowly diminish through the day on Sunday. Areas of blowing snow
are expected but visibility should remain above one mile for the
most part. South winds gusting to 35 mph through Atigun Pass have
prompted a Winter Weather Advisory for blowing snow until
midnight tonight. Travel may be difficult along the Dalton
Highway, however difficult conditions are expected to be short
lived. Temperatures will range from the teens above zero in the
Brooks Range to the teens below zero near Umiat and along the
coast. A frontal system moving north on Saturday will bring very
light snow accumulations to the Brooks Range on Saturday night and
Sunday and to the Arctic Coast late Sunday.

West Coast and Western Interior...

Strong area of low pressure slowly shifting northward through the
weekend will keep active weather around for the West Coast.
Latest observations an ATMS Snowfall Rate imagery indicate that
light snow has already spread northward towards St. Lawrence
Island and the western tip of the Seward Peninsula. A general 2-4
inches of snow is expected to most areas this evening through
Sunday night. Winds will be offshore through Saturday at 10 to 20
mph along the coast and 5 to 15 mph inland, but then turn onshore
and southwesterly on Sunday at 10 to 20 mph. Temperatures will be
mostly in the 20s, though colder air moving in aloft will bring
temperatures back to the single digits from Nome north by Monday.

Coastal Hazard Potential Days 3 and 4...

Multiple strong systems will push northward through the Bering Sea
late Monday night through Wednesday next week with strong
southerly onshore flow. At this time, the tracks do not appear
favorable for causing elevated water levels with the low pushing
into the Gulf of Anadyr; however large spreads still exist in
ensemble low tracks for this system. Still keeping an eye on the
potential for sea level rises if these systems were to track a
little further east. Water pushing up through the sea ice enough
to make travel difficult is certainly a possibility with these
systems.

Extended Forecast For Days 4 Through 7...

Strong upper ridging builds across Interior Alaska and the North
Slope Monday through the rest of the week and potentially
persisting into next weekend. Much warmer and drier conditions for
most of the Interior and North Slope this week with highs above
freezing for the west coast and YK Delta. Expect strong
inversions overnight with valleys still dipping into the teens
below zero by early morning hours.

For impactful conditions, focus shifts to the West Coast where
multiple rounds of precipitation and potentially high winds will
occur Monday through Wednesday. EC EFI continues to highlight the
YK Delta and Seward Peninsula for high wind potential Tuesday and
Wednesday as a strong baroclinic zone sets up in this region. Potential
is there for Blizzard conditions at times for the YK Delta and
then for St. Lawrence Island Late Monday into Tuesday as the
surface low pushes in from the south. This is a very
"atmospheric river" like set up with an intense S-N upper jet
overhead and a strong low level jet underneath pumping in ample
moisture and warm air northward. Once the main low pushes north, a
S-N axis of precipitation may set up along the West Coast
bringing additional periods of snow and rain and potentially mixed
precip types, with rates heavy at times. While there still is
uncertainty regarding the actual low track, confidence is increase
for high winds, warmer air above freezing and multiple rounds of
precipitation for the west coast.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Winter Weather Advisory for AKZ832-834.
     High Wind Warning for AKZ837-847-849.
     Winter Weather Advisory for AKZ809.
PK...Heavy Freezing Spray Warning for PKZ801.
     Small Craft Advisory for PKZ802.
     Heavy Freezing Spray Warning for PKZ802.
     Brisk Wind Advisory for PKZ803.
     Brisk Wind Advisory for PKZ805-809.
     Brisk Wind Advisory for PKZ806-807-816-851.
     Brisk Wind Advisory for PKZ810.
     Gale Warning for PKZ811-857.
     Brisk Wind Advisory for PKZ812>814-817-859-860.
     Brisk Wind Advisory for PKZ815.
     Heavy Freezing Spray Warning for PKZ850.
     Brisk Wind Advisory for PKZ852.
     Brisk Wind Advisory for PKZ853.
     Gale Warning for PKZ854.
     Gale Warning for PKZ856.
     Gale Warning for PKZ858.
     Brisk Wind Advisory for PKZ861.
&&