958
FXAK68 PAFC 301315
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
515 AM AKDT Tue Sep 30 2025

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

The forecast generally remains on track with some improvements in
the model agreement for the midweek storms. Currently, the low
that had been over the Gulf of Alaska is now exiting southeast,
leaving mostly zonal flow in the upper levels. The trough to the
north is moving across the Alaska Range and into the Copper River
Basin this morning. Generally quiet weather conditions can be
expected for today for most of the region, though snow showers
will become a bit more widespread, especially across the Tok
Cutoff Road, from Slana north through Mentasta Pass through the
rest of this morning. Light snow accumulations, on the order of
around an inch, are possible in this area.

The coolest overnight low temperatures will shift east for
Wednesday morning as thicker cloud cover moves in from the west
and starts to moderate surface temperatures by a few degrees.

Although slight differences remain in the models with timing,
overall consensus is beginning to align. A front arrives to the
western Gulf early Wednesday morning with a surface low forming in
the northern Gulf later in the day. Most places west of Prince
William Sound will see some precipitation by early to mid-morning
Wednesday. The exact amount, especially in the lee of the
mountains, will be dependent on the orientation of the flow aloft
and the extent of southerly gap winds. Another round of
precipitation will likely spread north across most of Southcentral
Thursday as the surface low tracks into Prince William Sound.
Precipitation looks to diminish for most locations by Friday.

-TM/Rux

&&


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

Currently, as of the morning, clear skies are prevalent across
the southwest Mainland as a ridge passes through the region. This
is allowing temperatures to once again drop to the mid-20s.
Meanwhile in the Bering, a front from a large low moving into the
Bering Strait is causing a line of small craft winds and
precipitation to affect from St. Matthew Island, down through the
Pribilofs, to north of the Andreanof and Fox Islands. This front
will progress eastward over the course of the day and will arrive
in the mainland by this (Tuesday) afternoon. The front will bring
warmer air along with it, so low temperatures in the mainland will
not be as cold Tuesday night.

Wednesday has the upper trough slide down into the mainland,
allowing for continued chances for precipitation. A north Pacific
low will barely "scrape" the Andreanof Islands before moving
southeast, causing a brief period of higher southerly winds. The
low will, however, will interact with the aforementioned trough,
allowing for a long uninterrupted line of rainfall from Adak to
the Alaska Peninsula. A ridge will build into the western
Aleutians by the afternoon and will quickly progress eastward,
reaching the mainland by Wednesday night/early Thursday morning.
Rain chances will quickly diminish and winds will become more
westerly all across the Bering and into the mainland. Cold air
advection from the trough that passed the mainland will allow for
night time temperatures to drop into the 30s as skies clear.
Temperatures are not expected to be as cold as the previous event.

Friday sees a North Pacific low move up into the Western and
Central Aleutians by the afternoon. Gusty gale force to storm
force winds and heavy precipitation are expected with this low.
Looking ahead to the weekend has the low continuing through the
Eastern Bering, eventually ending up west of Nunivak Island by
Sunday. This could cause issues with coastal flooding in the
Kuskokwim Delta Coast as south-southwesterly winds impact them.
There is still some uncertainty with this event, so changes are
likely as the low continues to develop. Continue to monitor the
forecast for future updates on this low.

-JAR


&&


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

The end of the workweek starts out with a Chukotsk low broadening
out into a trough of low pressure over northern and central
Alaska by Friday, with multiple weak embedded lows. Additionally,
a strong system approaches the western Aleutians, evolving into a
dominate Bering Sea storm. This system intensifies by Saturday,
sprawling across the Bering and moves towards Nunivak Island by
Sunday, possibly causing some minor coastal issues along the
Kuskokwim Delta with steady southwesterly onshore winds as this
system continues on towards Norton Sound before weakening sightly
at the of the forecast period. A separate low near the Kenai and
Alaska Peninsula Thursday weakens into a broad trough by Saturday
before being absorbed into the bering storm`s wind field by Sunday
and fully merges with it by Sunday and pushes a frontal system
into the western Gulf of Alaska by monday afternoon.

The major models predict the Bering Sea system over the weekend.
The European and Canadian models continue to be in agreement
trough day 7, with the CMC slightly stronger and faster. The GFS,
however, is still the slight outlier with its earlier forecast
period moderately different than its counterparts but improves
towards the end of the forecast period but still is not in full
agreement with the other 2. The Canadian is currently favored as
it leads the trend of the system moving south and east, ending up
weaker and closer to the Yukon Delta towards the end of the
period.


-DD


&&
.AVIATION...

PANC...VFR conditions, and light and variable to light northerly
winds, will persist. There is a chance for vicinity fog this
morning, with chances diminishing after 16Z.


&&


$$