208
FXAK68 PAFC 131443
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
543 AM AKST Mon Jan 13 2025

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

The powerful low that moved through Southcentral yesterday has
moved north and weakened as compared to yesterday. That is leaving
southwest Alaska under south-to-southwest flow aloft early this
morning. There is a short wave trailing the low that has moved
northward overnight and is bringing mainly rain showers with it
and some gusty southerly winds in its wake. These winds and
showers should diminish as the morning wears on as it moves into
the Susitna Valley and into the Interior this afternoon. For the
north Gulf coast, there will be persistent rain and snow showers
through the day, but the heaviest ones are expected to be through
mid-morning in the Thompson Pass area where there may be some snow
rates of 1 to 2 inches an hour. The next low can be seen on
satellite approaching the Gulf of Alaska from the south. This low
is not as strong as this past one an is tracking farther east.
This should bring some snow back to the north Gulf coast this
evening and overnight. The main dynamics of this low will be east
of the area, though there is some uncertainty as to whether there
could be a little bit of snow that develops over the Anchorage and
Matanuska Valley areas this evening as another weak shortwave
moves up Cook Inlet and mets the westernmost part of the moisture
from this low. Even if there is some snow in these areas, it won`t
be much accumulation at all. However, once we get to this
evening, it should be cold enough for any precipitation to be snow
for the next few days for all areas of Southcentral.

A low will and upper level trough will move into the area again
Tuesday night. This low looks to bring some snow to the Gulf coast
and coastal mountains, but the way the upper level trough is
undercutting the Kenai Peninsula, it will likely be little or
nothing for any inland areas.

&&


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

The large storm-force low pressure system in the eastern Bering
Sea is continuing to produce gusty easterly winds across the
Eastern Aleutians and Alaska Peninsula. Rain and snow will
continue for Southwest Alaska through tonight, though
precipitation has become more showery in nature as colder air
continues to wrap in behind the system leading to minimal
additional snow accumulation through this evening before tapering
off overnight. As the storm continues to lift northward along the
western Alaskan coast this evening, winds will pick back up and
turn westerly- southwesterly for Southwest Alaska with sustained
winds of 30 to 35 mph along the coast.

Southwesterly winds contribute to continued coastal flooding
potential, with a Coastal Flood Advisory remaining in effect for
the Kuskokwim Delta coast, particularly between Kipnuk and
Kwigillingok coincident with high tide tonight and Monday evening.
A High Surf Advisory also remains in effect as the strong onshore
push of winds through Bristol Bay will bring elevated water
levels there as well for high tide tonight through early Monday
morning. The main threat with this is likely to be high surf and
potential for coastal erosion along the Bristol Bay coast.

Out west, a compact gale-force low tracks near the western
Aleutians. With a cold air mass moving into the western Bering
Sea, there is also potential for blowing snow for those islands
this evening through Monday morning, however the showery nature of
precipitation will likely make visibility reductions below one
mile intermittent. The cold air mass spreads across the Bering Sea
and into Southwest Alaska with the northward exit of the large
low tonight, dropping temperatures into the 20s for Monday, the
teens Monday night, and single digits by Tuesday night. Expect
this colder air mass to also bring drier conditions across the
region as well for the beginning of the week. The gale force low
over the western Bering tracks into the northern Bering for
Tuesday, spreading snow showers as far as the Pribilof Islands
before diminishing by Wednesday morning.

-JH/Quesada

&&


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

On the Alaska Weather map, an elongated upper level trough
stretching from the Russian Far East across the Aleutians and
Bering. This trough gets a little boost from passing shortwaves to
reorient over Southwest Alaska and the Gulf of Alaska for
midweek, before continuing its Eastward track into Canada by
Thursday. An upper ridge building across the Western Aleutians
Tuesday moves to extend across the Gulf of Alaska and Western
Alaska into Northeast Russia through the end of the week.
Deterministic GFS and ECMWF carry the features and changes well
through Thursday with the Canadian models joining up into the
weekend.

A decaying surface low on the Southcentral coast spreads locally
heavy rains along the coastal locations, with locally heavy snow
further inland and over higher elevations through Wednesday. A
second low over the Shumagin Islands brings mostly rain with snow
over Bristol Bay from the Eastern Aleutians, Alaskan Peninsula and
Kodiak Island through midweek, before moving over the Kenai
Peninsula before dissipating over Prince William Sound Thursday.
Bands of snow progress across the Bering through Thursday. A well
developed North Pacific low and fronts spreads snow changing to
rain across the Western and Central Aleutians Wednesday and
continues over The Bering, Southwest Alaska and the AKPEN by
Friday. Gusty winds with gale force gusts work their way from the
Central Aleutians over the AKPEN and Bering through Friday.

&&

.AVIATION...

PANC...A secondary round of strong southerly winds ongoing is
expected to slowly diminish as the day progresses. The higher end
gusts as strong as 35 to 40 kts are not expected to persist for
more than a few hours this morning, and gusts should quickly drop
to 25 kts or lower by this afternoon, then go light and variable
by this evening. Rain showers could intermittently move over the
terminal and briefly cause ceilings to dip into MVFR range
throughout the morning, but otherwise VFR conditions are expected
through this evening. There will be potential for fog and/or low
stratus development after winds shut off tonight with possible
MVFR conditions or lower returning.

&&
$$