538
FXAK68 PAFC 310159
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
459 PM AKST Thu Jan 30 2025

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

A low that had been sitting closer to the Prince William Sound
yesterday has since moved off into the far eastern Gulf, leaving
behind mostly clear skies under a developing longwave ridge across
most of Southcentral. A few cloud streets and light snow showers
persist across the Gulf this afternoon, but everywhere over land
is now precipitation-free. Gusty offshore gap winds continue to
affect the usual spots typical of a cold air outbreak such as this
one, including near Whittier, Seward and the Valdez Arm.

Quiet, clear and very cold conditions are still on track into the
upcoming weekend. Temperatures will steadily but slowly warm each
day through Sunday as a strong subsidence inversion develops
under the ridge as it continues to build overhead. Gap winds will
also very slowly drop off with time as the cold air mass and high
pressure over interior valleys both begin to moderate, though
drainage flow out of the Copper Basin could be a bit stubborn to
drop off through the Copper Delta and Thompson Pass. The coldest
temperatures with this Arctic air outbreak will likely happen
overnight tonight into early Friday over most of the interior
valleys and lower elevations as clear skies, calming winds and low
dew points combine to create very favorable conditions for the
surface to radiate out heat after sunset. Precipitation chances
will stay close to zero through the start of next week.

-AS

&&


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

Key Points:

* Blizzard Warnings for the Kuskokwim Delta coast and Western
  Capes continue through tonight.

* Warmer air moves across Southwest Alaska through this weekend,
  raising temperatures to or above freezing for most areas.

Temperatures across Southwest Alaska have starting to rise this
afternoon, warming above Cold Weather Advisory criteria.
Temperatures will still be in the single digits along the coast
and inland to Bethel and New Stuyahok tonight, with -10F to -20F
in the lower Kuskokwim Valley. A higher rate of warming moves in
tomorrow as the front pushes inland, bringing a much warmer
airmass with it. Expect temperatures to reach into the upper 20`s
and low 30`s along the coast tomorrow before tracking to inland
areas Saturday.

Blizzard conditions are expected to continue along the Kuskokwim
Delta coast south to the Western Capes of Bristol Bay. Anticipate
gusting to 40 mph and visibilities reduced to one-quarter mile or
less with total snow accumulations of up to 10 inches. Winds will
be weaker in interior locations near Bethel, limiting visibility
reductions to between one-half mile and one mile at times. Other
areas across Bristol Bay will see light snowfall and occasional
reductions in visibilities.

High pressure ridging with southerly flow will build in over
Southwest Alaska this weekend following the passage of the current
front, leading to drier and warmer conditions. The Central and
Western Aleutians will continue to experience active weather
through the period as multiple shortwaves from the North Pacific
move across the island chain into the western Bering Sea,
bringing widespread rain and gale-force winds.

-KM/JH

&&


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

The high amplitude flow pattern over the Alaska Region will
undergo some brief duration but significant changes through the
forecast period. An upper level Kamchatka low retreats into the
Russian Arctic, while its elongated trough through the Central
Bering slacks up a bit due to transitory shortwaves through
midweek. The upper level North-South ridge over Mainland Alaska
will be flattened somewhat on Wednesday during the shortwave
passages. However, the ridge re-establishes itself in a broader,
more tilted orientation from the Gulf of Alaska across Western
Alaska into the Bering by Thursday. Model confidence using a
clustered GFS/ECMWF/Canadian blend for the larger scale features
remains quite good, while reducing the uncertainty over the finer
details.

A Kamchatka surface low extends a front through the Western and
Central Aleutians and Bering for Monday. Southerly winds with
locally moderate snow on the leading Northern edge of the front
changes to rain through the Central Aleutians and Bering and
dissipates in the Northern Bering late Tuesday. A North Pacific
low and front slip across the Western Aleutians late Tuesday.
Locally moderate rain and gusty winds with areas of gale force
gusts spread over the Western And Central Aleutians and Bering
Wednesday and Thursday. Interior Alaska lingers under more
seasonal temperatures and variably cloudy skies.

-KZ

&&

.AVIATION...

PANC...VFR conditions and northerly winds around 5 to 10 kts will
prevail through the TAF period.

&&

$$