485
FXAK68 PAFC 021238
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
438 AM AKDT Thu Oct 2 2025

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

An upper level shortwave trough is currently driving through
Southcentral with its attendant surface low making its way into
the Copper Basin this morning. A sharp back edge to the rain,
which has been moderate to heavy in some areas, can be seen on
radar over Fire Island as of 4 am this morning. As the trough
swings through today, a lee-side low will form along the Coastal
Chugach, pulling strong gap winds through Whittier and Seward with
some cold air advection to help ramp up the flow. For the
daylight hours today, most of the rain will be over the Copper
Basin, wrapping up in the McCarthy area by sundown.

For Friday, mostly zonal flow will dominate the area as ridging
builds in to the west. A trough moving through the Interior in the
morning may help to bring some rain or rain snow mix to the
Alaska Range and possibly as far south as the Talkeetna near
Hatcher Pass. Other than maybe Palmer and Sutton, most non-
mountainous areas should remain dry as the airmass dries out off
of the Western Alaska Range.

Moving into the weekend, a stout ridge is developing south of the
Gulf, with a broad trough and deep low pressure system over the
Bering Sea. This will really amplify the flow aloft and place
Southcentral into deep south to southwesterly flow. There is some
uncertainty as to the timing of the first shortwave that will
bring the rain, and to how waves rounding the southern periphery
of the trough will interact with the ridge, but the upper level
set-up is one that could be primed for heavy rain. Right now the
most likely areas for more concentrated precipitation will be the
Susitna Valley, Seward, Valdez and Cordova. Temperatures aloft
will also soar, pushing snow levels up to the 7000+ ft level later
in the weekend.

&&


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

Scattered rain showers expected through this afternoon for
portions of the Kuskokwim Delta and lower Kuskokwim Valley as a
shortwave trough moves from west to east. For the Alaska
Peninsula, winds through the gaps and passes will be gusty this
morning through the afternoon. Weak zonal flow sets up this
evening ahead of a fast-moving ridge of high pressure arriving
Friday.

A strong low moves into the Bering Sea late tonight, bringing
widespread gale force winds and precipitation to the Bering Sea
and Aleutian Chain. A pocket of storm force winds is expected near
the Central Aleutians Friday morning. Current guidance brings
southerly to southwesterly flow into the Mainland from the
Kuskokwim Bay to Kipnuk Saturday morning into Sunday. Therefore,
confidence remains moderate that minor coastal impacts from this
storm could occur.

&&


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

An amplified pattern will be in place on Sunday with a broad
trough over the Bering, extending well south of the Aleutians, and
high pressure located over the Gulf of Alaska. Deterministic and
ensemble guidance take the trough eastward into the Gulf of Alaska
early next week on Monday, as multiple shortwaves work to break
down high pressure over the Gulf. Initially, this should result in
unsettled weather for the Bering and Southwest Alaska, with
scattered showers and areas of gusty southerly winds into
Southwest Coast. Unsettled weather will shift eastward into
Southcentral with the passage of the trough on Monday. Southerly
upslope flow into the coastal mountains will result in potential
for heavier rain into Prince William Sound, while southwest flow
will bring moisture up Cook Inlet with additional showers. High
pressure attempts to build back over the Bering on Tuesday, but
model consensus is in good agreement with the arrival and
deepening of a large western Bering low Tuesday night into
Wednesday. This feature at the end of the long term forecast
period could bring high winds to the Aleutians or Pribilof
Islands, depending on how strong the low is and its exact track.
How forecast models resolve the deepening low the next several
days will be worth keeping an eye on.

BL


&&

.AVIATION...

PANC...MVFR conditions return to VFR later this morning as
ceilings quickly lift with a front exiting the area. South to
southwesterly winds diminish, becoming light and variable by the
afternoon. South to southwesterly winds return late this evening
and continue to gust as high as 25 kt through Friday morning.

&&

$$