490
FXAK69 PAFG 212322
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
222 PM AKST Tue Jan 21 2025

.SYNOPSIS...
A series of storms will impact the west coast through the week. A
strong front will set up over the west coast Tuesday into
Wednesday. A heavy band of snow will set up from the Seward Penn
to the Kobuk Valley. Winter Storm Warnings remain in effect for
these areas. A stronger storm will impact the west coast and
Northwest Alaska Thursday into Friday bringing high winds, heavy
snow, and some mixed precipitation south of the Seward Penn. This
system will also impact the Western north slope and Brooks Range
Friday into Saturday with high winds, snow and blowing snow.
The potential for heavy snow as well as possible mixed
precipitation over the Western and Central Interior this weekend,
then turning much colder towards the end of the month over much of
the area.

.DISCUSSION...

Key Weather Messages:

Central and Eastern Interior...

- Much warmer than normal temperatures continue this week with
  highs mostly in the 20s before most areas reach the 30s on
  Friday and over the weekend.

- Southerly gap winds through Isabel and Windy Passes will
  continue to gust to 60 mph into Wednesday. Wind Advisories are
  in effect.

- Areas of heavy rain and snow are expected beginning late
  Thursday night and Friday morning, mainly west of Fairbanks.
  Over a foot of snow possible for higher terrain locations along
  the Dalton Highway and from Bettles west.

West Coast and Western Interior...

- A strong front will set up over the west coast Tuesday into
  Wednesday. A heavy band of snow will set up from the Y-K Delta
  to the Kobuk Valley. Winter Storm Warnings have been issued for
  portions of the west coast, including the Seward Penn. Snow
  totals could be up to a foot in some spots depending on snow
  ratios. Winter Storm Warnings remain in effect for these areas.

- The system on Tuesday looks to northeasterly wind gusts up to 35
  mph from the Seward Peninsula to the Y-K Delta. We could see
  significant visibility restrictions in areas that are receiving
  the heaviest snow as well as gusty winds.

- After this next system moves out of the area late Wednesday,
  there will be another weaker shortwave moving through the west
  coast late Wed into Thursday, then a more impactful system late
  Thursday into Friday. This system looks to be bring strong
  winds and heavy snow initially, then mixed precipitation as it
  moves northeast through Saturday. Gusts over 60 mph are possible
  along the coast. Another foot of snow is possible along the
  Nulato Hills, Seward Penn and Kobuk Valley.

North Slope and Brooks Range...

- Well above normal temperatures continue today from the Brooks
  Range to the Arctic Coast. Expect temperatures mainly in the
  20s, with colder air filtering back in from west to east through
  Wednesday.

- Strong winds, snow and blowing snow will begin to develop over
  the western north slope and Brooks Range on Friday as a strong
  low and tight gradient swiftly moves through the area. The north
  slope and Brooks range temps will bottom out on Sunday and
  beyond as the strong cold front sweeps through the area over the
  weekend.


Forecast Analysis and Confidence...

Upper level pattern shows an upper level low near Wrangel Island
will continue to track to the NE over the Arctic. Another upper
low will move into Bristol By on Tuesday and another shortwave
move through the west coast late Wednesday into Thursday. An upper
level low over E Russia will develop and be the main player for
the late Thursday Storm over the west coast. Southwestly flow
will set up over the west coast and Interior Thursday and into the
weekend as the main upper low tracks NE across the Arctic. This
will be a good set up for parts of the western Interior to see
several inches of snow.


A strong front will set up over the west coast Tuesday into
Wednesday. There will be rapid frontogenesis along this boundary
creating a very narrow band of heavy snowfall. Heavy band of snow
has shifted slightly to the west to include the Seward Penn. Have
upgraded the last of the watches to warnings. We are trending to
the ECMWF solution as the ECMWF/GFS ensemble support that solution
as well as the Nam. Snow totals will be 8 to 12" of snow along
this boundary. Models are still in some disagreement on the
the timing of the precip and precip type that will be moving
across the western Interior and Central Interior over the weekend.


Extended Forecast Days 4-8...

A major pattern shift is likely by the end of the week as flow
turns more southwesterly and a number of strong low pressure
systems enter the Bering Sea. The overall pattern is favorable to
bring an abundance of warm air and precipitation northward over
western Alaska and possibly into the central and eastern Interior.
Expect a strong storm with high winds across the West Coast on
late Thursday into Friday, with increasing chances for heavy
precipitation in the Interior late Friday through Sunday as well
as gusty winds over higher terrain of the Interior. Some areas
will see heavy snow and there could be mixed precipitation as well
over the Interior. There is still some model differences on
timing and amounts and precip type. Models indicate an increasing
probability for very cold temperatures early next week behind this
system.

Coastal Hazard Potential Days 3 and 4...Impactful storm will
produce near Storm-force winds offshore as well as possible water
moving over the ice or any open leads along the coastlines of the
Y-K Delta and Norton Sound and Northwest Alaska late Thursday into
Friday. Shorefast ice may be lifted, and minor flooding may occur
in areas where shorefast ice is lifted. There is a high amount of
uncertainty in terms of what the impacts of this storm will be
due to the track, time of year, and ice extent. Without ice in
place, this would be a major coastal storm. Given the extent of
the ice and thickness, impacts are expected to be minimal, so no
coastal flood products will be issued at this time. The Potential
for coastal impacts remains south of Hooper Bay and Nunivak
Island.



&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Wind Advisory for AKZ847-849.
     Winter Storm Warning for AKZ813-816-819-822-823.
     Winter Storm Warning for AKZ824>826-829-830.
PK...Heavy Freezing Spray Warning for PKZ801.
     Small Craft Advisory for PKZ802.
     Heavy Freezing Spray Warning for PKZ802-803.
     Small Craft Advisory for PKZ803-804.
     Heavy Freezing Spray Warning for PKZ804.
     Gale Warning for PKZ805.
     Brisk Wind Advisory for PKZ806-816-817-851-852.
     Brisk Wind Advisory for PKZ807-856.
     Brisk Wind Advisory for PKZ810-811.
     Brisk Wind Advisory for PKZ812-853-858.
     Brisk Wind Advisory for PKZ814.
     Brisk Wind Advisory for PKZ815.
     Brisk Wind Advisory for PKZ850.
     Gale Warning for PKZ854.
     Brisk Wind Advisory for PKZ857.
     Brisk Wind Advisory for PKZ859.
     Brisk Wind Advisory for PKZ861.
&&

$$