Gale Warning 221, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
527 AM AKST Wed Mar 4 2026

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through
3/This afternoon through Friday afternoon)...

Key Messages (no significant changes to previous forecast):

* Cold Weather Advisories are once again in effect for the Seward
  area, Whittier, and Thompson Pass through noon tomorrow.

* A period of snow is likely for Kodiak Island overnight tonight
  into Thursday morning.

* Expect a gradual trend towards warmer and cloudier conditions as
  incoming storms begin to break down the ridge of surface high
  pressure over the Mainland.

* Though forecast confidence remains low to moderate, we're
  monitoring the potential for widespread snow, with the potential
  for coastal rain, as a strong low pressure system approaches
  from late Thursday through Friday.

Discussion:

The short-term forecast remains on track through late Thursday
with the Arctic trough anchored over Mainland Alaska slowly
giving way to a more amplified and active weather pattern for
later this week. Currently, this feature is keeping bitterly cold
temperatures in place across Southcentral with clear skies for
all but the Copper River Basin as moisture from a low in the
eastern Gulf is lifted northwestward by a negatively tilted trough
over the Kenai Peninsula. Cold Weather Advisories remain in place
through noon today for the Seward area, Whittier, and Thompson
Pass as gusty gap winds allow frigid wind chills to persist.
Confidence is fairly high that conditions will warm by tomorrow as
winds diminish, and as incoming moisture and cloud cover helps to
moderate air temperatures.

The aforementioned low and trough are allowing the moisture to
wring out in the form of snow for the eastern Copper River Basin
with several inches of snow likely for McCarthy before the trough
exits later today. There us be a sharp cutoff in the cloud cover
and precipitation along the western periphery of the trough,
resulting in much lighter snow accumulation toward the Richardson
Highway.

Farther upstream, a short-wave over the Seward Peninsula will
continue to dig southward across western AK this morning,
developing into an upper low before stalling over Southwest AK
Wednesday through Thursday. The subtropical jet stream in the
Pacific will then reorient from the North Pacific to the Gulf and
help steer storm systems quickly across the Gulf. The first,
weaker low will arrive Wednesday night and Thursday with gusty
easterly winds across the northern Gulf and a period of snow for
Kodiak Island, with up to 2 inches of accumulation possible by
Thursday morning for Kodiak City. The easterly flow across the
northern Gulf will also result in snow showers across Prince
William Sound through Thursday.

By Thursday into Friday, a much stronger storm moves in from the
North Pacific. There remains uncertainty with the track of this
stronger storm, owing to questions of how this incoming upper low
will interact with the aforementioned one lingering over
Southcentral. Still, this storm will likely be robust enough to
bring widespread precipitation across Southcentral Alaska, with
the potential for periods of moderate to heavy snow, blowing snow
for some coastal locations at the onset of snowfall, and a snow to
rain transition for Kodiak Island and along the Prince William
Sound coast. Due to uncertainty with the low track, it's
difficult to say, for now, what snow/rain amounts or potential
impacts may be; however, favored locations - Turnagain Pass,
Portage Valley, Western Kenai Peninsula, Western Susitna Valley,
Valdez, and the Southern Copper River Basin - could all see
several inches of snow with this system. Stay tuned.

-KC/TM

&&

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

A deep Arctic airmass remains firmly entrenched over mainland
Alaska and the Bering Sea, with northerly flow maintaining the
cold air across the region. The prolonged nature of the pattern
has resulted in growth and advection of sea ice across the
northern and eastern Bering Sea, with the ice edge approaching the
Pribilof Islands. As the cold air moves over open water,
stratocumulus clouds and snow showers develop. These clouds and
showers cover nearly the entire Bering Sea and Aleutian chain.
Southwest Alaska remains mostly clear and cold.

A strong disruptive storm system is poised to move out of the
Northern Pacific Thursday into Southern Alaska. While solutions
are confident on a northward surge of this system, there is a
large spread in both operational and ensemble solutions. The storm
track ranges anywhere from Kodiak Island to Bristol Bay, creating
a high level of uncertainty in the forecast. The past few model
runs have trended toward more wind and precipitation affecting
Southwest Alaska Thursday afternoon through Friday morning,
especially along the Alaska Peninsula and into Bristol Bay. Given
the strength and persistence of the current cold air mass over the
region, confidence is high that precipitation from this system
will remain cold enough for mostly snow. The current forecasted
storm track would keep Unalaska and Akutan on the periphery of the
system, but may see some blowing snow. Snow and blowing snow with
reduced visibilities will be the primary impact to travel. As
such, Winter Storm Watches have been issued for Unalaska/Akutan,
the Alaska Peninsula, and Bristol Bay. Locations along the Alaska
Peninsula near Cold Bay, are expected to see the highest potential
for the most impactful conditions, with the area potentially
seeing blizzard conditions.

Meanwhile, a second compact upper low will drop southward out of
eastern Russia tonight and across the western Bering and Aleutians
Wednesday through Thursday. A weak surface low will also form
beneath the upper center. This will bring stronger winds and
heavier and more sustained snow showers to the Aleutians from
around Adak west to Shemya.

As the low tracking across southern AK exits Friday, Arctic air
will come back southward across the eastern Bering and Southwest
Alaska, leading to an increase in winds and snow showers,
especially along the Alaska Peninsula. This will take us right
back to the pattern we've been in for much of the past few weeks.

-CL

&&

.LONG TERM FORECAST (Days 4 through 7 - Saturday through Tuesday)...

Upper-level troughing centered over the northern Gulf of Alaska
will extend south into the Northern Pacific, with multiple
shortwaves rotating around the trough. Some model differences in
the position and track of resulting surface lows lifting into the
Gulf will continue to keep the precipitation forecast confidence
below average for the long term. A lean towards the GFS ensembles
brings a shortwave over the Western Aleutians by mid to late week
with a shot of colder temperatures dropping southward out of
Northeast Russia and into the western Bering. Strong
northwesterly flow and cold air advection will lead to the
potential for strong gap winds across the Barren Islands and
Southern Alaska Peninsula. While forecast confidence is low with
regard to where surface features and precipitation ultimately
develop, forecast confidence is high that both Southwest and
Southcentral Alaska will continue to see below normal temperatures
through the end of this week.

&&

.AVIATION...

PANC...VFR conditions and light winds are expected to persist.

&&