Storm Warning 187, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
452 PM AKST Mon Dec 29 2025

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3/Tonight
through Thursday)...

Key Points:

* Strong and gusty winds continue across much of the region this
  afternoon, but expect a general weakening trend as we head
  through the evening. A High Wind Warning remains in effect for
  the Matanuska Valley, where wind gusts are still reaching as
  high as 70 mph.

* A Winter Weather Advisory is also in effect for
  Thompson Pass, where winds which have started to decrease.
  However, snow will continue to be lofted by these gusty winds,
  reducing visibility through 9 pm tonight.

* Periods of heavy snow showers will reduce visibility along the
  southern Kenai Peninsula this evening. A Winter Weather Advisory
  remains in effect for Seward and travelers should use caution
  while traveling in the area.

* Portions of Kodiak Island, including Kodiak City could also
  experience low visibilities in blowing snow tonight. However,
  there is low forecast confidence in the track of surface lows
  and associated precipitation in the Gulf, so this will continue
  to be closely monitored.

* There will be additional chances of snow across the region
  through Thursday. However, the bigger story will be another
  surge of cold air and winds Tuesday through Tuesday night. This
  will come in from the northwest, with the strongest winds
  expected across Kodiak Island and the western Gulf.

The Arctic trough which brought another round of cold and winds to
Southcentral is now being pushed back to the north and west as a
series of short-wave troughs track northward across the Gulf of
Alaska into Southcentral. At the surface, an elongated surface
low and occluded front are lifting toward the north Gulf coast.
Radar imagery shows a particularly consolidated area of
precipitation tracking up across the northern Gulf toward the
Kenai Peninsula, while a band of light snow that swept across
much of Southcentral today is drifting west over Cook Inlet.
Across Prince William Sound, some light snow showers are present.

Winds have been slow to diminish across the region today, but are
still forecast to decrease this evening into tonight as warmer
air filters in from the series of shortwaves lifting over
Southcentral Alaska, loosening up the pressure and thermal
gradients that are driving the winds right now. The aforementioned
Arctic trough and associated strong jet will be pushed all the
way into Southwest AK where it will begin to shear apart. While
temperatures will warm, the airmass coming from the Gulf will not
be warm enough to change precipitation to rain for land areas.
Precipitation will generally be light, but the combination of wind
and low density snow means the snow will be easily blown around
and reduce visibilities. A Winter Weather Advisory remains in
effect for Seward, where stronger winds persist this evening and
a robust shortwave rotating around the Gulf low looks to bring
moderate to heavy snowfall during the later evening hours. Through
Thompson Pass, windy conditions are lofting snow from the ground
and reducing visibility, so the Winter Weather Advisory has been
retained for that area as well. Meanwhile, other locations are
not expected to see more than intermittent blowing snow due to the
largely showery nature of the precipitation.

Kodiak Island has a chance to see heavier snow and blowing snow
depending on the track of key features across the western Gulf
tonight. Stay tuned, as this can be a good pattern for blizzard
conditions in Kodiak City if precipitation backs in from the Gulf,
with persistent north to northwest surface winds holding in the
cold air. However, current thinking is that the low center and heavier
precipitation associated with it remains too far east and
therefore stays largely offshore. We will continue to monitor the
potential for changes to the forecast tonight.

The low in the Gulf shifts east on Tuesday, pulling the larger
trough over Southwest Alaska eastward. Some weak shortwaves will
keep a chance of snow in the forecast tonight through Wednesday,
especially over interior Southcentral. However, any snow
accumulation with these features will be light. More
significantly, a potent short-wave and strong jet streak will dive
southeastward across Southwest AK Tuesday night and into the
western Gulf Wednesday. This will bring yet another surge of
Arctic air and strong winds. The strongest winds will be over the
western Gulf and Kodiak Island, with good potential for Hurricane
Force wind gusts (65 kt) along the south side of the Alaska
Peninsula into the western Gulf and for Storm force gusts (50 kt)
for Kodiak Island. Secondarily, all of the gap winds along the
north Gulf coast and Prince William Sound will restrengthen. The
northwesterly flow will be particularly conducive for strong winds
in Whittier/Passage Canal, but thankfully, this is NOT conducive
for strong winds in the Matanuska Valley. In fact, winds will
likely be light there. No surprise, the cold spell will continue
across the region.

-SEB/CQ

&&

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

An upper level ridge continues to slowly build over the central
and western Bering this morning, allowing for quiet conditions and
light winds to prevail across the central and western Aleutian
Chain. An impressive temperature and pressure gradient persists
over the eastern Bering, causing very strong north to northwest
flow across the eastern Bering Sea, AKPen and parts of Southwest.
The strongest winds are focused along and south of the AKPen,
where channeled flow through mountain gaps is further enhancing
winds. High-end Gale force winds with Storm force gusts are
ongoing along parts of the Pacific side of the AKPen. Wind gusts
here will peak Tuesday as hurricane force gusts are expected, with
winds expected to come down by Wednesday morning. This very
strong north to northwest flow has kicked up areas of dust and ash
built up from old eruptions near a few volcanoes, including
Westdahl and Shishaldin. Trace amounts of ashfall from resuspended
ash will be possible over waters immediately south of Unimak
Island until winds begin to subside later by midweek. Across
Southwest, gusty but not as strong winds continue, especially
across parts of Bristol Bay. The gusty winds coupled with
temperatures in the -0s to -10s are creating frigid wind chills
ranging from -10 to -40 this morning.

Across Southwest, temperatures will slowly rebound several degrees
by Tuesday and through midweek as the very cold northerly flow
pulling down Arctic air from the interior also becomes more
northwesterly with time. From Tuesday night into Wednesday, a
fast-moving shortwave trough and associated low will move into the
Seward Peninsula, sending a trailing cold front into the
Kuskokwim Delta. A line of snow showers moving along the front
will bring a very quick- hitting round of light snow to the
Kuskokwim Delta as the front brushes past late Tuesday night.
Limited moisture plus the short duration of snowfall will cap off
snow accumulation to half an inch or less through early Wednesday.

Across the Bering and Aleutians, conditions will become a bit more
unsettled as a North Pacific low pushes a front across the
Aleutian Chain into the southern Bering from Tuesday into
Wednesday. Temperatures will stay warm enough for purely rain
along the front as it lifts steadily northeast and spreads light
to moderate precipitation into the region. Winds along the front
will be nothing out of the ordinary, barely reaching Gale force
sustained as the front arrives near the central and western
Aleutians from Tuesday afternoon into Wednesday morning.

-AS/CL

&&

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

A rex block will be in place at the start of the long term
forecast period with ridging over the central Bering Sea and
troughing over mainland Alaska and the western Bering Sea. Cold
temperatures will descend over southern Alaska where areas of the
Kuskokwim Delta may see temperatures as low as 40 below zero. Most
of mainland will be under dry conditions while the Aleutians
continue a showery regime.

The main weather maker at the end of the weekend will be an
Aleutian low as it progresses eastward and breaks down the Bering
ridge. Deterministic models are in fairly good agreement for being
this far out in time, currently prognosticating between 950 to
960 mb as it moves into the Bering Sea on Sunday. Expect high
winds to possible storm-force as this system traverses over the
Chain. Moderate to heavy precipitation looks likely as moist
southerly flow associated with the frontal system moves over
southern Alaska. This will be one to keep an eye on going forward.

&&

.AVIATION...

PANC...VFR conditions and ceilings above 5000 ft expected through
the period. Gusty north winds gradually diminish through late this
evening, with gusts to drop below 25 kt overnight. A trough may
bring a period of light snow/flurries through late this evening,
with any accumulations at the surface expected to be minimal due
to the dry air currently in place.

&&