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FXAK68 PAFC 120128
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
528 PM AKDT Sat Oct 11 2025

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

Gulf of Alaska ridge moves eastward as Bering Sea low progresses
onshore. Multiple fronts cross Southcentral bringing increased
cloud cover, strong winds and rain through early next week.

Satellite shows increasing cloud cover across the Prince William
Sound west to the Gulf of Alaska and Kodiak Island this afternoon
as a weak front pushes northward. Scattered rain showers were
reported in these areas today with the greatest at 0.10" at the
Kodiak airport measured as of 4:00 pm. A second wave of moisture
shown on the radar over the Alaska Peninsula continues to push
northeastward over Kodiak Island and into the Kenai Peninsula.
This second wave brings more robust moisture and warmer air
resulting in widespread light rain showers this evening and
overnight for most of Southcentral and Kodiak Island. Rainfall
amounts range from a few hundredths to a few tenths of an inch
from this second wave of moisture. Though temperatures in the
Copper River Basin and at higher elevations in the Chugach
Mountains could lead to a mix of snow and rain at the onset of
this second wave of moisture, a change over to all rain will occur
as snow levels rise overnight. A third wave of moisture pushes
into Southcentral tomorrow afternoon bringing continued cloud
cover, warm air and precipitation to Southcentral Alaska.

Wind speeds increase through the day today across Southcentral
Alaska in conjunction with the multiple waves moving through the
region. Easterly winds this afternoon through the Barren Islands
ranging from 25 to 35 knots can be expected. Small craft
advisories and gale warnings there continue into this evening.
Farther north, easterly winds through northern Prince William
Sound and Turnagain Arm, including the Anchorage Hillside, range
from 35 to 55 knots overnight. The 500 mb NAM and GFS signal an
increased likelihood of these winds moving over west Anchorage as
the southerly to southeasterly wind component increases. These
winds through the Anchorage Bowl persist into tomorrow afternoon.
A barrier jet forms along the Prince William Sound coastline
tomorrow morning and continue into the evening hours creating
small craft to gale strength warnings over the ocean.

&&


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

Key messages:

 - The forecast remains on track for a powerful storm (remnants of
   Typhoon Halong) to bring dangerous High Winds to the Pribilof
   Islands and Kuskokwim Delta and Storm Surge Flooding to many
   communities along the Kuskokwim Delta coast and lower
   Kuskokwim River.

 - Preparations for these dangerous conditions should be concluded
   as soon as possible. Weather conditions will rapidly
   deteriorate as the storm crosses the central Bering Sea late
   this afternoon and evening.

 - Another powerful storm system will move out of the Pacific on
   Tuesday. All signs indicate that this storm will take a more
   southerly track across the southern and eastern Bering Sea and
   impact all of Southwest Alaska Tuesday through Wednesday. Stay
   tuned as we work to hone in on the most likely track and
   weather impacts.

A look at satellite imagery shows what is now an extra-tropical
storm (which formed from the remnants of Typhoon Halong) tracking
northward across the south-central Bering Sea. It is slowly
strengthening right now, but a strong upper level short-wave
trough and jet streak noted in water vapor are about to catch up
to the surface low and lead to more rapid intensification as we
head through the evening hours. The primary change in the last few
model cycles is to delay onset of intensification, though the
rate of intensification as the low passes west of the Pribilof
Islands late this evening and tracks toward the west coast of
Alaska early Sunday is very similar. Despite the fact the low is
now expected to bottom out around 960 mb tomorrow morning (10 to
20 mb weaker than model solutions from prior days), this has had
little effect on the wind forecast. This shows the power of rapid
pressure falls ahead of the storm and rapid pressure rises behind
the storm. The actual pressure gradient plays a critical role in
the wind strength as well. The other notable trend in model
guidance is a continued eastward shift in low track as it moves up
the west coast of Alaska. This provides increased likelihood of
some of the greatest impacts from winds and storm surge being felt
along the Kuskokwim Delta coast and Nunivak Island.

Bottom line, the forecast and expected weather hazards from this
powerful storm are all on track. Minor adjustments have been made
to the exact timing and strength of the winds and High Wind
Warning effective times have been adjusted accordingly.

As far as the storm surge threat along the Kuskokwim Delta coast,
the slight change in storm track and timing has now better
aligned the time of tomorrow morning`s high tide with the peak
surge of water from the Bering Sea. The expected water levels are
still in line with what we have been advertising (3 to 6 feet
above the normal highest tide line), but this provides confidence
to lean toward the higher end of guidance. This will surely lead
to significant flooding in coastal villages, especially for Kipnuk
where this could be the highest water levels they have seen in
the past decade. The alignment of high tide and storm surge also
gives confidence that there will be some minor flooding along the
lower Kuskokwim River. Therefore, have upgraded the Flood Watch to
a Flood Advisory from Bethel south to the mouth of the Kuskokwim
River. Communities that often see flood impacts in this scenarios
include Tuntutuliak and Napakiak.

The storm will exit northward up the west coast of Alaska on
Sunday, leading to slowly improving conditions as we head through
the day. A long-wave trough will remain over the region, with
numerous weak features transiting the Bering Sea, Aleutians, and
Southwest AK Sunday through Monday night. Attention will then
shift to the development of another large and strong storm system
over the North Pacific on Tuesday. As always, there is fairly
large model spread and uncertainty in storm track due to
differences in timing of a short-wave digging out of USIA and
interacting with a low crossing the North Pacific. The one
consistent trend in guidance over the past couple days is to move
up the timing of intensification of the low which causes it to
slow down and take a more southerly track along the Aleutians and
southern Bering Sea. Although this does not look like a repeat of
the current storm, there is still potential for significant
weather impacts across the eastern Bering Sea and Southwest
Alaska, so stay tuned to forecast updates over the next few days.

-SEB

&&


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

The long term forecast starts with weak ridging over the Gulf of
Alaska which will recede, allowing a strong frontal system to
advance in from the west, delivering heavy coastal rainfall and
gusty winds across the coastal regions of Southcentral AK. Down-
sloping winds may reduce rainfall in the Anchorage and the Mat-Su
Valley. However, strong winds could reach Prince William Sound and
Anchorage Bowl, depending on the front`s eventual track across
the region. Models are in fair agreement with this scenario. Zonal
flow will develop as the weekend approaches, decreasing the winds
and reducing rain intensity. Scattered showers may linger in
higher elevations and coastal areas.

In the Bering, a low from the North Pacific arrives Wednesday and
into Thursday, tracking eastward of extratropical cyclone
Halong`s path, towards Bristol Bay and the Alaskan Peninsula,
bringing gale-to-storm force winds and heavy precipitation to the
Kuskokwim Delta to the AKPEN. Coastal flooding and erosion is
again possible along this region. As the weekend starts, a more
zonal flow will setup across the state, allowing a brief respite
from active weather before another possible deep low approaches
the Central Aleutians by the end of the weekend. This is quite far
out, so the evolution of this event is still somewhat uncertain.
It will be important to monitor the forecast as updates are
issued.

-DD

&&


.AVIATION...

PANC...Expect VFR conditions to prevail for most of the TAF
period. Some light rain is possible overnight through Sunday
morning. If any MVFR ceilings develop the most likely timeframe
should be on Sunday morning. Surface winds should remain mostly
northerly until Sunday midday when the Southeasterly Turnagain Arm
wind is expected to move over the airport. There is a chance for
low level wind shear overnight through Sunday morning due to the
northerly surface winds and southeast winds aloft around 2000
feet.

&&


$$