249
FXAK68 PAFC 020039
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
439 PM AKDT Thu Oct 1 2026

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

Radar returns this afternoon show a band of precipitation moving
westward towards the northern Cook Inlet region from the Prince
William Sound, with some of the precipitation also moving
northward towards the Matanuska Valley. With cold air aloft and
above freezing temperatures across much of the northern Cook Inlet
region and Valley locations, precipitation type is largely going
to depend on intensity of showers that move across this stretch of
Southcentral. During heavier precipitation rates, expect a
rain/snow mix or all snow until showers begin to taper, whereas
light precipitation should mostly be in the form of rain. 500 mb
heights and vorticity analysis shows that the base of a neutrally
tilted trough axis is moving over Southcentral now, and until this
feature clears the area later this evening and overnight, expect
periods of showery conditions to continue. The GFS deterministic
runs continue to consistently show a slower progression of this
trough axis lifting out of the region and more over the Copper
River Basin by midnight or so. In the wake of the trough Friday
morning, clearing skies, light winds, and radiational cooling will
allow for temperatures to fall into the mid to upper 20s for most
of our population centers from Anchorage to the Matanuska and
Susitna Valleys. One caveat is that if we do see patchy fog or
freezing fog forming for some of the valley locations Friday
morning, overnight low temperatures may be slightly warmer than
what we are advertising, but there is high confidence (80 percent)
that much of Southcentral will see its first hard freeze of the
season. Depending on how much precipitation falls today, be on the
lookout for areas of patchy black ice for your Friday morning
commute.

Looking farther eastward and stepping forward in time, the upper
trough will continue to bring showers to the Copper Valley through
around noon to 3PM Friday as it lifts out of the region. To the
south, a high end small craft to gale force complex low pressure
system enters the gulf Friday afternoon. This will first affect
Kodiak Island with northeasterly gales and a round of rainfall
through the weekend. A large swath of precipitation associated
with this system lifts towards the northern Gulf coast through
Saturday afternoon. There is still a bit of spread in the models
between timing of precipitation arrival to the Gulf coast, but
there is much higher confidence (70 to 80 percent) in an easterly
gale force barrier jet setting up along the northern Gulf coast,
and gales located in the southern Cook Inlet and Shelikof Strait
as this system draws closer to the coast Saturday morning through
Saturday afternoon. Coastal ridging will set up shop along the
Gulf coast prior to this system`s arrival, which in turn will most
likely increase gap winds for the Turnagain Arm, Knik River
Valley, and Copper River Basin. Stay tuned.

-AM


&&


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

Satellite imagery depicts a low pressure system with a high end
small craft front moving eastward across the central Bering while
upper level cloud cover can be seen streaming northward from a
North Pacific low that is approaching the Alaska Peninsula.
Nestled in between these two systems is a fog and low stratus bank
locked in across the eastern Bering, North Pacific, and also
across the Kuskokwim Delta region for areas like Bethel.
Meanwhile, outside of areas of fog across Southwest Alaska,
isolated to widely scattered showers and thunderstorms have
developed with daytime heating and from weak waves embedded within
the 500 mb mean flow from a ridge of high pressure anchored
across the Cook Inlet region of Southcentral. The focus and
highest confidence of thunderstorm activity this afternoon through
early tomorrow morning will along the slopes of the Kilbuck
Mountains and near Lime Village, with convection moving north-
northeastward with time. This will be the last day of thunderstorm
potential for Southwest Alaska due to the North Pacific low
moving northward through the short term forecast period, which
will bring in a more stable airmass and displace any instability
potential farther north and out of the region.

By mid Wednesday morning, the Bering low nears the Pribilof
Islands as its front slowly weakens. To the southeast, the North
Pacific low continues to lift northward. Its leading front will be
capable of southeasterly small craft winds, with even stronger
winds flowing through favored gaps, bays, and passes of the Alaska
Peninsula and across the Bristol Bay waters. The movement of the
North Pacific low will nudge the ridge farther northeastward and
the flow becomes more difluent across Southwest Alaska heading
into Wednesday afternoon.

&&

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

The seasonably active weather pattern continues through the long
term period, beginning with broad troughing spanning across the
eastern Bering Sea to the southern Mainland early next week. A
weakening surface low shifts into the Gulf Monday into Tuesday,
with southerly flow and ample moisture keeping the eastern Kenai
and northern Gulf coast wet through midweek as the low slowly
tracks east across the northern Gulf. For the Alaska Peninsula,
Bristol Bay, and inland Southcentral locations, expect unsettled
and showery weather to continue through early next week as weak
shortwaves rotate through the upper level flow. Additionally,
gusty northerly winds enhanced by cold air advection on the back
side of the low will be possible across the eastern Aleutian
Islands and AKPen, especially through favored gaps and passes.

By mid to late next week, a potentially more impactful storm is
expected across the Bering as the next Kamchatka shortwave
interacts with tropical energy lifting north out of the North
Pacific. Widespread rainfall and strengthening winds are expected
to reach the western Bering and Aleutian Islands Wednesday into
Thursday before spreading east across the rest of the Bering and
Aleutian Chain through the remainder of the long term period.
Significant model spread remains in the evolution of this storm as
the two systems interact in the North Pacific and Bering Sea, but
strong winds and periods of heavy rain are beginning to look
increasingly likely by late next week across the Bering and
Aleutians.

&&


.AVIATION...

PANC...MVFR with rain and snow showers will gradually taper off
this afternoon. Confidence is medium-low for the timing of each
shower and when the precipitation ultimately ends. Skies should
start to clear late, after 04Z, though freezing fog may develop
overnight. Otherwise, mostly sunny skies and north/northeast
winds will prevail Friday afternoon through Friday night.


&&

$$