Gale Warning 579, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
537 AM AKDT Fri Oct 3 2025

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

Quiet weather today across the region as zonal flow shifts to
southwesterly as the ridge axis moves in from the west. The first
notable change to the weather pattern will be increasing clouds
from the west as upper level moisture spills over the ridge,
followed next by increased southerly gap winds as a coastal ridge
builds. On Saturday, a warm front will push through the region,
bringing widespread rain and breezy winds to most areas. The
moderate cross-barrier winds will help limit some of the rain
accumulations for Anchorage, Mat Valley and portions of the Kenai
Peninsula, but the broad south to southwest flow in the mid-
levels will bring plentiful rainfall to the Gulf coast and Susitna
Valley. For those who were enjoying seeing snow on the area
peaks, this system will usher in much warmer air, with snow levels
rising to around 7kft over the weekend, so runoff from snowmelt
and rain on snow may cause some enhanced river rises. This is due
to the highly amplified pattern that is setting up with a strong
blocking ridge over most of the northeastern Pacific.

Moving into Sunday the warmest of the air will be pushed off into
Southeast Alaska, as the upper level trough nudges over Southwest
Alaska and the Alaska Peninsula. Models have come into better
consensus that the upper trough will lift into the Gulf and
possibly into Southcentral, whereas yesterdays guidance had the
trough sliding south of the ridge. This pattern evolution will
mean more prolonged precipitation for Southcentral, or at least
the Gulf areas, as well as a return of cooler (though still above
normal) temperatures aloft.

&&

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

A weak disturbance continues moving across interior portions of
Southwest Alaska this morning where rain showers persist across
the Kuskokwim Valley and along the Western Alaska Range. High
pressure across the eastern Bering Sea and the rest of mainland
Southwest Alaska will continue to move inland today. As it does
so, flow will switch to southwesterly and eventually to southerly
as warmer air moves in through today.

A strong low pressure system, currently over the Western
Aleutians, will continue to lift north-northeastward through the
west-central Bering to just west of St. Matthew Island by Saturday
morning. A corridor of southerly storm-force winds will accompany
the initial front today across the coastal waters of the Central
Aleutians and into the south-central Bering. Moderate to heavy
rain across the Western and Central Aleutians today works to
northeast to the Pribilof Islands by this afternoon as the Eastern
Aleutians and southern Alaska Peninsula (AKPEN) see light rain
tonight through Saturday morning. Gusty southerly to southeasterly
gap winds are also likely through the favored bays and passes of
the Eastern Aleutians and southern AKPEN today through Saturday
afternoon.

Gusty southerly winds will pick up today along the Kuskokwim
Delta Coast beginning late this morning. Southerly to
southeasterly winds will peak very early Saturday morning before
diminishing beginning mid-morning Saturday. Peak wind gusts along
the coast are expected to be in the 40 to 50 mph range. Along with
this push of southerly flow will be a water-level increase of
around 1 to 2 feet above the normal highest tide-line and wave
heights between 8 to 10 feet in the coastal waters of the
Kuskokwim Delta. The high waves and water-level increase could
cause localized areas of erosion along the Kuskokwim Delta Coast,
as well as localized low lying areas to fill with water. However,
significant coastal flooding is not anticipated with this system.
With respect to precipitation across mainland Southwest with this
system, most of it stays confined to Nunivak Island and extreme
northwest portions of the Kuskokwim Delta Coast, around Toksook
Bay and Tununak for Saturday morning.

The pattern further amplifies on Saturday as the broad trough
across the Bering Sea digs farther south into the North Pacific.
As this occurs, a shortwave will lift across the AKPEN, into
Bristol Bay, and eventually across mainland Southwest Alaska
Saturday afternoon and evening which will help rain to become more
widespread across Southwest. Light to moderate rain, with pockets
of heavy rain, will persist across Southwest Alaska and the AKPEN
through Sunday as additional shortwaves lift northward from the
North Pacific over the area. The best chance for heavier rains
looks to come Sunday as a more robust shortwave will help to spin
up a surface low in the North Pacific south of the AKPEN. This low
looks to elongate as it moves northward across the AKPEN and into
Bristol Bay by Sunday evening. Light to moderate rains spread
northward from Bristol Bay to interior Bristol Bay and the
Kuskokwim Valley for Monday.

Meanwhile, farther to the west, somewhat colder air behind the
weakening north-central Bering Sea low pressure across the Central
and Eastern Aleutians will give way to warmer air moving in from
the west Sunday. Off and on light rain looks to continue across
the Aleutian Chain this weekend into early next week. There are
some indications that an atmospheric river, driven by a strong
North Pacific ridge and a low pressure moving off of the Kamchatka
Peninsula, could start moving across the Western Aleutians and
western Bering Sea starting Monday afternoon. Stay tuned for
forecast updates regarding both this potential system and the
strong Bering low pressure slated for today through this weekend
as the active weather pattern continues.

&&

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

All of the active weather in the long term period will be
confined to west of the Alaska Range and largely over the Bering.
The one exception will be the potential for areas of heavy rain,
primarily along the Gulf coast, with the remnants of a trough over
the Gulf of Alaska. Southwesterly flow directed into the coastal
mountains will aid in ongoing precipitation to start the new work
week. Models are in generally good agreement with the trough
breaking down on Tuesday and dissipating completely by Wednesday.
This will leave high pressure in place over Southcentral Alaska
and largely benign conditions for the region late Tuesday through
the Thursday.

The main concerns for the long term period involve the
development of a large upper low over the Bering on Tuesday. While
much uncertainty remains, strong southerly flow is likely to
develop downstream of the trough, with gusty conditions forecast
for the Aleutian Chain up into the Pribilof Islands. Something
that will be worth keeping an eye on will be the potential for
persistent onshore flow into the Kuskokwim Delta. Locations near
Kongiganak and Kwigillingok could see coastal flooding,
conditional upon the track of the low and intensity of onshore
flow. Tuesday morning into Tuesday night would be the main time
frame of concern. Low pressure then weakens and lifts northward on
Wednesday followed by the repeat development of yet another large
Bering Sea low Thursday into Friday. For the moment, models are
keeping the 2nd low further west, which will keep the Kuskokwim
Delta Coast in the clear.

BL

&&

.AVIATION...

PANC...Southerly winds continue to gust up to 25 kt this morning
before winds relax this afternoon. Late tonight, most likely after
midnight, a southeasterly Turnagain Arm wind begins to move over
the terminal. Winds gust as high as 25-30 kt by Saturday morning.
Ceilings remain VFR above 5000 ft until the next front begins to
move in Saturday morning, when ceilings have potential to drop
below 5000 ft with light rain.

Quesada

&&