Gale Warning 117, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
442 PM AKST Mon Jan 27 2025

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

Cold air wrapping around a low pressure system to the west has
resulted in an unstable airmass across Southcentral, bringing
widespread showers to the region. Locally heavy bands of intense
snow have been observed today moving inland off Cook Inlet from
the southern Kenai Peninsula all the way up to the Susitna Valley.
Being convective in nature, the exact timing, location, and
magnitude of the snow showers have been a forecast challenge, but
reports everywhere from 0" to 9" of daily snow totals have been
observed today, varying greatly across short distances.
Southwesterly flow will likely allow snow showers to persist along
upslope areas of the Chugach, Kenai, and Talkeetna Mountains
through Tuesday. Isolated to scattered showers are also likely for
lower elevations.

A reinforcing shot of colder air will also begin to work in on
Tuesday as a more potent shortwave moves east from the Alaska
Peninsula. By Tuesday night, this feature will likely help
initiate northerly and westerly gap winds for places like Seward
and Whittier as temperatures elsewhere fall to more seasonal for
this time of year. Thompson Pass will also see an increase in
gusty gap winds due to cold air advection from the Copper River
Basin as the flow switches to northerly. Blowing snow or blizzard
conditions are possible as there should be plenty of transportable
snow from the previous storm. By Wednesday, the entire upper-
level low may drop over Southcentral, bringing yet more cold air
across the region and stronger northerly gap winds to the mountain
passes and Southcentral coast. This trend of dropping
temperatures and increased gap winds will continue into Thursday.

&&

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

Conditions are winding down across much of Southwest Alaska and
the Bering/Aleutians through tonight. Pockets of light snow may
linger across portions of the lower Kuskokwim Valley and northern
portions of Bristol Bay through this evening. As a whole,
anticipate drier and colder over the next few days for Southwest
Alaska. A much colder airmass moves out of the north and spreads
across the Southwest Mainland. Temperatures are expected to drop
into the minus teens tonight and minus 20F's with wind chills in
the -30F's Tuesday night/Wednesday night for the Kuskokwim Delta
and lower Kuskokwim Valley. Bristol Bay will be "warmer" with low
temperatures reaching the minus teens Tuesday night/Wednesday
night. The Alaska Peninsula will be the "warmest" with
temperatures from -4F to 18F between Pilot Point and False Pass
respectively. Daytime temperatures will be subzero for all areas
except from Pilot Point south on Wednesday.

The next weather driver will be an incoming front set to
move over the Western Aleutians tomorrow. A band of gale force
winds surrounded by widespread small craft will move west to east
across the Bering Sea through the end of the week. Precipitation
will move along the front, starting as snow initially and
transitioning to rain as warm air encroaches in. The
Western/Central Aleutians will likely see very little, if any,
snowfall due to already having temperatures at or above freezing
prior to precipitation. The front reaches the Pribilof Islands by
Wednesday morning, bringing rounds of snowfall and gale force
winds. There is potential for blowing snow conditions, though some
uncertainty remains with how quickly the warm air can overtake the
snow. Similar conditions are expected along the Kuskokwim Delta
Coast by Thursday.

-KM

&&

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

Seasonably cool temperatures continue over much of the
southeastern half of the State as the longwave trough over the
Bering Sea retreats back towards the Arctic and the building high
pressure ridge shifts towards the East. Several shortwave troughs
with associated surface lows will move through the Gulf of Alaska
through the end of the week producing moderate coastal rain and
mountain snow to Prince William Sound and into the Copper River
Basin. Cooler air across the Interior to the Kenai Peninsula,
Kodiak Island, Anchorage and Mat- Su Valleys will start to warm as
more southerly winds return to the area early next week.
Precipitation during this time is favor a rain/snow mix later
transitioning to more rain at the lower elevations at the start of
the new week.

A building pressure gradient will produce strong southerly winds
across the Central Aleutians through the Western Alaskan Peninsula
and Southern Bering Sea through the end of the forecast period.

-DD

&&

.AVIATION...

PANC...VFR conditions are expected to persist through the TAF
period. Gusty southerly up-inlet flow will gradually diminish in
speed through Tuesday before become northwesterly tomorrow
afternoon or evening.

&&

SPECIAL WEATHER STATEMENT
National Weather Service ANCHORAGE AK
119 AM AKST Tue Jan 28 2025

AKZ181-185-290200-
Alaska Peninsula-Eastern Aleutians-
Including the cities of Cold Bay, Sand Point, Unalaska,
and Nikolski
119 AM AKST Tue Jan 28 2025

......STRONG WINDS AND PERIODS OF BLOWING SNOW EXPECTED FOR THE
EASTERN ALEUTIANS AND SOUTHERN ALASKA PENINSULA THROUGH THIS
EVENING...

Widespread snow showers will continue through this afternoon for
the Eastern Aleutians and through this evening for the Southern
Alaska Peninsula (Nelson Lagoon and west). Snow showers combined
with gusty northwest winds up to 50 mph could significantly reduce
visibilities at times. The worst conditions and lowest
visibilities for the Eastern Aleutians are expected now through
this morning with conditions improving during the afternoon. The
worst conditions and lowest visibilities for the Southern Alaska
Peninsula (Nelson Lagoon and west) will be mid-morning through the
afternoon with conditions beginning to improve through the
evening and overnight hours tonight. Use caution if traveling.