Unalaska, Alaska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

140
FXAK68 PAFC 061256
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
456 AM AKDT Fri Jun 6 2025

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

Today will be the nicest day of the week for most areas as some
ridging moves overhead. While it will be sunny for most locations
through at least midday, high level clouds will begin to
overspread Southcentral in the afternoon ahead of the next system
for this weekend. A low lifting into the Gulf of Alaska will help
to build a coastal ridge, inducing southerly flow and generating
another round of pesky gap winds through Turnagain Arm, the Knik
and Copper River Valleys. The Copper River wind will likely
inhibit shower development over much of the Copper River Basin,
but locations north and east of the Wrangells and also in the
northern basin (near Paxson and along the Denali Highway) have
potential for isolated thunderstorm development on Friday
afternoon/evening. A few isolated showers and thunderstorms are
also expected along the western faces of the Talkeetna Mountains
and possibly over the Parks Highway. Later in the evening, the
leading front reaches Kodiak Island and eventually the Gulf coast
early Saturday morning.

The front brings strong winds along the north Gulf coast, reaching
storm force near Kayak Island. The position of the low will break
down the coastal ridge tomorrow morning, and gap winds will
generally diminish for Saturday. Widespread rain will once again
blanket the region through the day as the Gulf low interacts with
another polar trough digging across western Alaska. Guidance
yesterday indicated that the polar low would shift into the Gulf
on Monday, but most model guidance has shifted away from that
solution, which will likely yield to a more prolonged period of
showers extending into Monday or even Tuesday as the upper low
lingers over Southcentral. This will likely continue to evolve.

&&


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

Unsettled weather continues through the weekend as several storms
move across the forecast area. For Southwest Alaska, a North
Pacific low will graze the region as it moves near Kodiak Island
and into the Gulf. With the low center quite distant from
Southwest Alaska, the worst conditions will remain outside the
forecast area. However, there is still uncertainty with how
strong winds winds will be from tonight through Saturday. Have
leaned towards higher winds, with gales forecast between Kodiak
Island and Chignik. Expect breezy conditions as the low moves
through, then a potential for below-average temperatures as an
upper low nudging in from the north brings in a colder and drier
air mass. Have increased temperatures from the previous forecast,
with the thinking that clearer skies and daytime heating could
mitigate some of the cold air advection.

Shifting gears to the Bering Sea and Aleutian Islands, the main
player for now will continue to be the ridge, which is currently
located over the Western and Central Bering Sea. As seen on
satellite imagery, much of the Bering Sea is blanketed in stratus
courtesy of this ridge, with some fog around the Pribilof
Islands. The stratus and fog will continue until the ridge
erodes, which will occur gradually over the coming days as several
waves run up against the ridge`s western flank. Of note will be a
strengthening upper level shortwave and its associated surface low
moving into the Western Bering from Sunday evening into Monday
morning, which will bring the potential for a broad swath of 25+
kt winds and moderate to heavy precipitation.

-Chen

&&

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

A closed upper level low over Southwest Alaska takes a slow track
across the Gulf of Alaska to near Queen Victoria Island through
the forecast period. A weak upper ridge follows from the Eastern
Bering across Interior Alaska. A broad trough forms over the
Bering through Thursday. Using an ensemble of GFS / ECMWF / UKMET
and Canadian models carries a good level of certainty and
continuity. the weather pattern is setting up for a series of
transient storm systems.

On the surface, widespread rain with mountaintop snow extends
across most of the Southern Mainland through Tuesday, as a
decaying low moves across the Gulf of Alaska. In the West, a well
developed low and front spreads moderate to locally heavy rain
beginning in the Western Aleutians and Bering for Monday, and
pushing over the Northern Bering and Eastward into Southwest
Alaska and the Alaska Peninsula for Tuesday. Gusty winds are
expected over the Western and Central Aleutians Tuesday,
diminishing late. This system continues over Kodiak Island
Wednesday, slowly diminishing in areal coverage by Thursday. A
weak low trails behind with more rain over the Western Aleutians
through Thursday.

- Kutz

&&


.AVIATION...

PANC...VFR conditions will continue through the TAF period. An
approaching storm will increase the Turnagain winds through the
afternoon and late evening before the winds bend down the inlet
around 12Z tomorrow.

&&


$$