Ice Storm in Alaska, December 2 to 3, 2025

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
547 PM AKST Mon Dec 1 2025

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3:
This afternoon through Thursday afternoon)...

Winter Weather Advisories are now in effect for as the next front
approaches Southcentral Alaska. Here are the Advisories in
effect:
* Anchorage, Eagle River, and Lower Matanuska Valley (including
  Palmer and Wasilla): Rain/freezing rain coinciding with near-
  freezing temperatures tomorrow morning, bringing the potential
  for additional icing on roads.
* Along the Parks Highway from Houston north to Talkeetna: Snow
  and freezing rain from late tonight through early Wednesday
  morning, with 2-4 inches of snow and up to 0.15 inches of ice.
* Northern Copper Valley (Richardson Highway mile markers 150 to
  200) and Northern Susitna Valley (north of Talkeetna): 6-8
  inches of snow from late tonight through Wednesday morning.

Precipitation has largely tapered off as a shortwave ridge begins
to move into the Southcentral Mainland, bringing a short break in
precipitation for tonight. Clear skies have given rise to areas of
low stratus and fog, with patchy fog (which may be dense at times)
possible along Cook Inlet from Anchor Point north to Anchorage and
into the Lower Matanuska Valley. A Dense Fog Advisory remains in
effect for the Anchorage Bowl. When the fog will dissipate remains
uncertain, but it could linger through tomorrow morning as there
won't be much wind to scour it out.

Later this evening, a front will begin progressing northeastward
into the Gulf, reaching Kodiak Island just before midnight. Steady
precipitation begins early tomorrow morning as the front makes
its way into the Southcentral Mainland. Overall, with the front
weakening before it reaches the Southcentral Mainland, there won't
be very much wind or warm air advection. As such, expect
temperatures to remain much the same as we're seeing right now.
This will be a problem for the Anchorage area up to the Mat-Su
Valleys as this rain will be falling in areas where temperatures
are near or below freezing, and onto already-icy side and
neighborhood streets. For Susitna Valley in particular, localized
colder conditions near Willow will likely lead to higher ice
accumulations, especially with heavier precipitation in that area.
Further north, upslope flow onto the southern face of the Alaska
Range will lead to higher snow accumulations near Broad and
Isabel Passes.

-Chen

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (Days
1 through 3)...

A significant low level inversion persists over Southwest Alaska
this afternoon, in advance of a strong North Pacific low that is
moving toward the eastern Aleutians. This is setting up Southwest
Alaska for rain in the warmer air around Bristol Bay and a
significant ice storm for the Kuskokwim Valley and Delta. As this
low drives northward, it will elongate as it reaches the Aleutians
and pushes into the high pressure over the Arctic. This will
greatly enhance the pressure gradient and bring widespread Gale
and Storm force winds to the Bering Sea and adjacent coasts.

The biggest concern for the weather tonight into Tuesday night is
for the Kuskokwim region where this storm pumps in warm air aloft
over the cold surface air. This will result in a long-duration
freezing rain event for Bethel and along the Kuskokwim River from
tonight into Wednesday morning. Ice accumulations are expected to
one-half to three-quarters of an inch for this time period,
resulting in an Ice Storm Warning. To the north and west of the
Kuskokwim River in the Delta region, the arctic front will stall
out and create a significant thermal boundary. This is expected to
create Blizzard conditions for Nunivak and Nelson Islands
tomorrow. This change from freezing rain to snow/blowing snow will
likely be a sharp boundary, but Nunivak and Nelson Islands are
expected to see the worst of the blizzard conditions. By
Wednesday, the low center will still be in the Unalaska area, but
will have weakened enough to bring marine winds to Gale force and
allow the temperatures over the Kuskokwim region to fall below
freezing at all levels of the atmosphere which will end the
freezing rain threat. The Bristol Bay region will be slower to
cool off and may keep precipitation type as rain until Thursday,
especially for coastal areas. After Thursday, this the entire
region will drastically cool down and get quite cold for the
weekend.

&&

.LONG TERM FORECAST (Days 4 through 7 - Friday through Monday)...

An initial trough should be lifting into Southcentral on Friday
with light to moderate rain pushing into the coastal mountains
and a chance for a rain/snow mix for interior locations of the
Copper Basin, Anchorage and the MatSu Valley. On a slightly more
optimistic note, the time period from Friday into the weekend may
bring an end to the unseasonably warmer temperatures Southcentral
and Southwest Alaska have been experiencing as of late. A
previously active pattern trough over the Aleutians is forecast to
become closed off, allowing an arctic trough over the Seward
Peninsula to dive southward into the southwest coast. Much cooler
temperatures over Canada, previously shunted east of the ALCAN
border will spill into interior Alaska Friday into early next
week. Ensemble guidance and deterministic models all show a broad
trough overspreading the Gulf of Alaska Saturday into Sunday, with
a closed surface low developing somewhere east of the Kenai
Peninsula, south of Prince William Sound. This will open the door
for various scenarios to play out, conditional on the exact
placement of the closed low. A low further east may allow colder
temperatures to spread across the region more quickly while a low
further north might favor increasing snow chances for much of
Southcentral. Despite the uncertainties, a pattern change appears
likely during the long term forecast period with a significant
cool down in the not too distance future.

-BL

&&
.AVIATION...

PANC...The forecast for the remainder of this afternoon and
evening is quite challenging. Fog has settled in across the
Anchorage Bowl in a moist and stable environment. There is very
little change in the environment until low level flow strengthens
overnight. Thus, expect fog will linger. The fog is shallow, so do
suspect there will be some erosion from the edges, with improving
conditions as we head into and through tonight.

Another round of rain is on the way for tomorrow, with arrival at
the terminal at around 15Z. Assuming there is no clearing skies
this evening, surface temperatures will hover near or slightly
above freezing, then very slowly rise tomorrow morning. Thus,
conditions are not as favorable for freezing rain, though some
surfaces might be cold enough initially for some of the rain to
freeze on contact. Precipitation will be light and will end by
late tomorrow morning as downslope flow increases ahead of an
occluded front. As the front passes late Tuesday evening, may see
a weak wind coming off Turnagain Arm, which would likely warm
temperatures into the upper 30s. Should light north-northwesterly
remain at the surface, low-level wind shear will be possible.

-SEB/Rux

&&