Unalaska, Alaska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

977
FXAK68 PAFC 301300
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
500 AM AKDT Sun Mar 30 2025

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

Another quiet weather day is in store for Southcentral Alaska as a
ridge over the Bering Sea building into Southwest Alaska and the
Interior. The remnant front of a low which is now well south of
the Gulf has some clouds remaining over Prince William Sound to
Kodiak with some light rain offshore in the Gulf which could
briefly move over Kodiak this morning. With the ridge building
in, clouds should clear out from the northwest today over the
region leaving ample sunshine for inland areas through most of the
day with just the Prince William Sound are keeping some clouds
around until overnight Sunday night. As this ridge moves in, it
will also increase gap winds, so expect the winds around Kodiak
Island to increase overnight with Seward and Whittier following
suit tomorrow. With the flow aloft consisting of a northwesterly
direction by tonight, there will be an increase in winds around
Valdez, but they are not expected to be as strong as other areas
which are more favorable to northwest flow. This is also not a
good set up for the northeasterly Matanuska River winds,
especially without any significant cold air already in the Copper
River Basin.

By Monday night and Tuesday, this ridge will have flattened some
which will not only reduce the subsidence over Southcentral, but
put more westerly winds aloft in zonal flow. This will probably
allow the clouds back into Southcentral, though any light precipitation
is expected to be limited to along the Alaska Range. There is the
chance for some short waves, that can`t be detected yet, to
develop in this flow around the top of the ridge. That could
eventually increase the chances for precipitation for Tuesday and
beyond, but lower level moisture should be limited so any
precipitation would still be expected to be light.

&&


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

Few changes to the previous forecast. A strong ridge of high
pressure centered near the central Aleutians continues to bring an
expansive area of stratus across the Bering Sea and Southwest
Alaska. A pressure gradient between the high in the Bering and low
pressure in the Gulf of Alaska drives gap winds up to gale force
through the Alaska Peninsula and eastern Aleutians through today.
Winds diminish below gale force tonight into next week as warm air
associated with the high pressure spreads across the Alaska
Peninsula. A weak perturbation will ride around the ridge into
Southwest Alaska from this afternoon into the overnight hours,
supporting continued chances for light snow over mainly higher
terrain along the Kuskokwim Mountains. In the Kuskokwim Delta,
low-level moisture builds up under a strong subsidence inversion
under the strong upper ridge, meaning conditions will be ripe for
drizzle. Temperatures increase on Sunday to above freezing with
warmer air working in from the Bering Sea, but gradually cool
overnight, so precipitation may begin as rain or drizzle, but
likely transition to light snow or freezing drizzle through the
night.

Across much of the Bering Sea and Aleutians, fog will become
increasingly widespread through early next week as moisture
similarly builds up in the marine layer under the warmer air
aloft. Monday night, a potent cold front pushes into the western
Bering, bringing rain and southerly winds, though winds look to
remain below gale force. The change in air mass will be the most
notable impact of the front, with cold air sweeping in behind to
replace the high pressure. As a result, the Kuskokwim Delta and
possibly the Pribilof Islands see snow potential by Tuesday night.

&&


.LONG TERM FORECAST (Days 4 through 7: Wednesday to Saturday)...

The persistent upper level ridge across the Alaska region is
interrupted by an upper level trough from over the Bering Strait
on Wednesday. Snow showers spread across the northern interior but
dwindle out by Thursday.


On Friday, a North Pacific surface low moves north into
Southcentral, bringing rain, widespread gales and areas of storm-
force winds possible through the gaps and passes of the Aleutian
Chain on Friday and the northern Gulf coast on Saturday.
Simultaneously, a Kamchatka low pushes its front into the Central
Bering late Friday into Saturday.


&&.AVIATION...

PANC...VFR conditions and light winds will persist.

&&


$$