098
FXAK68 PAFC 050119
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
519 PM AKDT Fri Apr 4 2025

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3: Today
through Sunday)...

A large low pressure system with multiple embedded centers located
several hundred miles south of Kodiak Island has pushed a front to
the Southcentral coast today, where it will remain stalled out
through Sunday. Though the front brings moderate to heavy
precipitation along the coast, inland areas remain primarily
downsloped and therefore dry, with the main impact to sensible
weather being cloudy skies and warmer overnight temperatures as a
result.

A series of shortwaves lift north across Southcentral Alaska over
the next several days bringing increased chances for light
precipitation for inland locations at times. The first notable
shortwave lifts across the Copper River Basin tonight, allowing
for a brief shot of rain/snow down to the valley. Given overnight
temperatures in the mid 30s, any snow accumulations are likely to
remain minimal outside of the mountains. A second shortwave during
the day on Saturday could bring another round of light rain to the
Copper Basin. Then on Sunday, a more potent shortwave brings a
chance of rain to the Cook Inlet region. Near freezing
temperatures in Thompson Pass allow for a few inches of snow near
the road summit.

By Sunday night, uncertainty abounds with the track of a new,
consolidated center within the broad gyre of the North Pacific
low. The most likely track based on ensemble guidance tracks the
low into the western Gulf, near Kodiak, which would keep inland
Southcentral mostly dry, with similar conditions to today and
Saturday. However, there is a potential outcome (though currently
less favored) where the low tracks further north into the Gulf,
toward the eastern Kenai or even into Prince William Sound, which
would, in combination with cold air nudging in from the west, lead
to potential for more substantial snowfall for inland regions of
Southcentral. Regardless of low track, colder air does look to
work into the region, bringing much cooler temperatures Sunday
night into Monday from the Kenai Peninsula up through the Mat-Su
Valleys.

&&


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

...Key messages...

 1) A Winter Storm Warning has been extended until midnight AKDT
tonight for the Eastern Aleutians.

 2) A Blizzard Warning remains in effect through 7PM AKDT this
evening for the Kuskokwim Delta Coast and Nunivak Island.

 3) A Special Weather Statement remains in effect through 7PM AKDT
this evening for snowfall and strong winds for the Pribilof
Islands.


Active weather continues across Southwest Alaska due to a slow
moving system in the North Pacific. This afternoon it remains
several hundred miles south of the Alaska Peninsula and will
meander eastward through the weekend. A band of northerly flow
has brought 8 to 10 inches of snow and gusty winds to Nunivak
Island, Kuskokwim Delta Coast, and Eastern Aleutian Islands.
Drifts several feet deep and difficult road conditions have been
reported in Unalaska. Slightly weaker winds and snow may persist
overnight, however, these should significantly diminish on
Saturday as the band breaks down and the low complex continues
farther east, toward the Gulf of Alaska.


High pressure currently over the Western Aleutians will build
eastward in the wake of the departing system, bringing drier air
Sunday and into the new week. A weak front associated with a
system originating from the Sea of Okhotsk will clip the Western
Aleutians this weekend, but should mostly stay south of the
Chain.


&&


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

The main feature on the Alaska Weather map is the elongated upper
level trough stretching from the Arctic through Mainland Alaska
to the Gulf of Alaska and Eastern North Pacific through the
forecast period. A number of shortwaves slide through the flow,
partially eroding the upper ridge across Western Canada. The
Bering ridge continues to build through the week, becoming a
closed center across Northern Kamchatka by Friday. A blend of
ECMWF and Canadian models maintains good continuity over most of
the trough and the rest of the region through the forecast, while
the GFS becomes an outlier drawing its focus on the Arctic upper
low.

A decaying low South of Prince William Sound pushes locally heavy
rain over coastal zones from Prince William Sound to the Canada
Border, with moderate to heavy snow mostly over higher elevations
inland, diminishing Wednesday. A second low over the Kuskokwim
Delta spreads snow over the Southwest Alaska coasts and across the
Alaska Peninsula Tuesday. Gusty winds over the Eastern Bering
move across the AKPEN for midweek. This low crosses Kodiak Island
before swinging across the Gulf of Alaska through Friday. This
round of precipitation tapers off late Thursday over Kodiak Island
and the Kenai Peninsula before moving into open waters. In the
West, a well developed low over Southern Kamchatka extends a front
over the Western Aleutians Wednesday. Locally heavy rain and
windy conditions with gale force gusts expected to spread across
the Western and Central Aleutians and Bering through Friday.

- Kutz

&&.AVIATION...

PANC...VFR conditions will continue despite a low moving through
the Gulf of Alaska this weekend. Northerly winds will dominate at
the surface with easterly winds aloft. Therefore, wind shear is
possible through tomorrow morning though most likely this
evening. There is chance for snow early next week with the return
of cold air.


&&


$$