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FXAK68 PAFC 241335
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
535 AM AKDT Sun Aug 24 2025

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

The upper level ridge over Southcentral continues to weaken as it
is being squeezed by a low to the northwest and a low south of the
Gulf. This is allowing mid-level clouds to develop across
Southcentral early this morning though there is no rain to be seen
on radar or being reported on observations. As a shortwave ahead
of the main front moves eastward, it is expected to bring some
rain into the northern Susitna Valley by this afternoon and
farther south tonight to include Talkeetna and the Talkeetna
mountains. Palmer and Wasilla will be near the edge of this area
of rain though it should be fairly light for most areas except
perhaps along the Alaska Range.

Gap winds have been a bit tricky the past two days as models, MOS
data, and even the overall pattern indicate that there should have
been more gusty winds than what has occurred through any of the
typical areas such as Turnagain Arm and along the Copper River.
Suspect the main reason for this is due to a weaker than
anticipated surface ridge along the north Gulf coast resulting in
less of a pressure gradient. Models are once again showing these
winds increasing by this afternoon and there may be enough of a
change in the pattern to allow that to finally happen today. It is
also likely that once these winds get going they will persist for
a few days.

Looking towards the workweek... mid and long-range models are still
in agreement with an upper trough digging across the Bering and
down towards the North Pacific by midweek. Some of the coastal
areas along the eastern Kenai Peninsula and Kodiak Island will see
precipitation chances increasing Tuesday, but the better chances
for heavier precipitation looks to be Wednesday into Thursday. It
is still a bit out there in time, so will continue to see how
models start to resolve the timing and precipitation over the next
several days.

&&


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

The general thinking with regards to the forecast remains mostly
on track through the short-term period. Currently, a ridge in the
North Pacific extends across the Eastern Aleutians, Alaska
Peninsula (AKPEN), and into mainland Southwest Alaska. In
association with this ridge, fog has been observed at Unalaska,
Cold Bay, Egegik, and New Stuyahok early this morning. Back to the
west, a tropical moisture tap and atmospheric river continues to
advance northeastward across the Western and Central Aleutians
this morning where precipitable water values between 1 to 2 inches
are common. Higher-end precipitable water values are more
confined to the Western and Central Aleutians with lower values
north across the Bering.

The upper-level ridge discussed above will weaken through next
week. At the same time, a broad upper-level trough over Kamchatka
will amplify and dig further south into the North Pacific. This
will allow the atmospheric river to slide slightly southward and
into the Kuskokwim Delta this afternoon with light to moderate
rain. An additional low pressure system is currently spinning up
in the North Pacific this morning and will continue to deepen
today as it moves into the Bering Sea this afternoon. Moderate to
heavy rain will overspread portions of the Western and Central
Aleutians through today and make it to the Pribilof Islands and
Kuskokwim Delta Coast by tonight.

With the low track from the Western Aleutians today, to just west
or northwest of the Pribilof Islands overnight tonight, to the
vicinity of Norton Sound by Monday morning to Monday afternoon,
the atmospheric river will be pointed straight at the Kuskokwim
Delta and Nunivak Island tonight and Monday with periods of heavy
rain likely. Accompanying the heavy rain will be strong gusty
southerly winds into the Kuskokwim Delta Coast. Winds could gust
as high as 50 mph at times Monday morning through early Monday
evening before winds slowly weaken. In addition, elevated waves
are likely in the coastal water of the Kuskokwim Delta between 4
to 8 feet Monday morning through Tuesday morning before slowly
subsiding. A Special Weather Statement has been issued for the
Kuskokwim Delta Coast to bring more awareness to the strong winds
and increased waves/surf. Moderate to heavy rain at times will
also occur over the Eastern Aleutians Monday. However, heavy rain
is not expected to remain over the area with a rather quicker
progression to the east over the southern AKPEN by Tuesday
morning.

Yet another low spins up along the frontal zone Tuesday morning in
the eastern Bering Sea. This low elongates as it advances
northward to the Kuskokwim Delta through Tuesday afternoon and
evening. This will help shift moderate to heavy rain southward
over Bristol Bay as well as inland across the Kuskokwim Valley
Tuesday and Wednesday. All-in-all, this series of wet systems
looks to bring between 1 to 3 inches of rain across the mainland
Southwest and southern AKPEN today through Wednesday morning with
a general 1 to 1.5 inches of rain across the Aleutian and
Pribilof Islands. Highest totals across Southwest and the southern
AKPEN will be along the Kuskokwim Delta Coast, the northern
Bristol Bay coast, and between Sand Point and Kodiak Island on the
southern AKPEN. Lower-end totals are expected inland and on the
Bering side of the southern AKPEN. Looking ahead, the wet pattern
looks to persist into the end of the week. Stay tuned to the
forecast for updates as the wet pattern gets underway starting
today and tonight and lasts through much of next week.

&&


.LONG TERM FORECAST (Tuesday to Saturday)...

SOUTHWEST ALASKA, THE ALASKA PENINSULA WATERS AND THE ALEUTIAN
ISLANDS: A front associated with a Bering Sea low moves slowly
eastward allowing for southwesterly flow to prevail across the
area. Heavy rain and strong winds are expected through next
weekend as these southwest winds bring an atmospheric river to the
region. A longwave trough combines with this front as the Bering
Low retreats to the Bering Strait mid-week; enhancing the rainfall
in the Aleutians and Alaska Peninsula. Rainfall will become
heavier in Southwest Wednesday and Thursday. As the front moves
eastward, a ridge builds into the area toward the end of next
week.

Elsewhere: Rainfall from this atmospheric river reaches Kodiak
Island by the end of the week bringing heavy rain and gusty winds
to the Island. This rainfall spreads over the remainder of
Southcentral into the weekend though amounts will vary.

&.AVIATION...

PANC...VFR conditions will prevail through the period while
Anchorage remains under weak high pressure. Winds should remain
relatively light through much of today. However, a gradual
increase in winds is anticipated later tonight. Southeast winds
bending into the terminal could gust into the 20 to 25 knot range
closer to midnight tonight, and continue into much of Monday.

BL

&&


$$