Area Forecast Discussion
Issued by NWS Anchorage, AK

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674
FXAK68 PAFC 110052
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
452 PM AKDT Wed Sep 10 2025

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

The large low in the Gulf of Alaska continues to bring steady
rainfall and gusty winds to Southcentral Alaska. Currently, the
low center is just east of Kodiak Island. Steady rainfall
continues to fall along the Southcentral coastline as well as the
Susitna Valley from Skwentna north. Due to this constant rainfall
in the Susitna, the Yentna River near Lake Creek is near bankfull.
A Flood Advisory has been issued for the Yentna River near Lake
Creek with minor flooding possible by late Thursday evening. More
details can be found in the text of the advisory. As for the
Anchorage and western Kenai regions, downsloping easterly aloft
winds will initially limit rainfall. The aloft winds will
gradually weaken over the day and will allow for steady rainfall
to start falling by late Wednesday/early Thursday. As for wind
speeds, they will continue to slowly decrease along the
Southcentral coast as the low weakens when it stalls in the north-
central Gulf.

Thursday is much of the same regarding rainfall. Continued
rainfall will affect most of Southcentral Alaska including the
Mat-Su Valley, Anchorage, and the western Kenai. The Copper River
Basin will be drier, but still may see some isolated showers. Cold
air advection from western Alaska will allow for northeasterly gap
winds north and south of Kodiak Island to drain out regions such
as the Kamishak Gap. Friday has the low further weaken and begin
to dissipate. Rainfall will still affect the aforementioned areas
as long as the low survives, but it will get lighter and lighter
as time goes on. The low will fully dissipate by Saturday, leaving
lingering showers in higher elevations and the coast. Wind speeds
become light with the dissolution of the low. The cold air
advection mentioned before will be mostly at higher elevations
(850 mb). Due to this fact, there is a possibility that Anchorage
and the Mat-Su Valley could see termination dust at the tops of
mountains Friday or Saturday. A surface low will move into the
Gulf by Sunday morning, but it remains to be seen exactly what
kind of a track it will take. More or less winds and rain can be
expected depending on its track.

-JAR

&&


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

A weakening gale force low continues slowly into the western Gulf
of Alaska this afternoon. Between the low and a ridge of high
pressure over the central Bering Sea, northerly gale force winds
persist from Southwest Alaska, across the eastern Bering Sea and
the Alaska Peninsula, aided by cold air spilling south across the
region. Wind gusts as high as 56 mph have been observed in False
Pass today and wind gusts to similar intensity will continue to be
possible through this evening. Rain has diminished to fairly light
showers roughly along and east of a line from Dillingham north to
Sleetmute.

Tonight, cool, dry air sourced from a digging Arctic trough over
Western Alaska continues to push a cold front across Southwest
Alaska, clearing out precipitation (and skies) from west to east.
By Thursday morning, light showers hang up only along the Western
Alaska Range. Increasingly clear skies and cool air will drop
temperatures across Southwest Alaska into the mid 30s to low 40s
tonight. Though winds begin to diminish tonight across the region,
they will likely still be significant enough to prevent most
locations from seeing freezing temperatures. Heading through
Thursday, winds trend below gale force through and south of the
Alaska Peninsula. By Thursday night, cold air and relatively clear
skies remain in place as winds calm across Southwest Alaska,
which could allow for the first true frost/freeze for many
locations across Bristol Bay and the Lower Kuskokwim Valley.
Temperatures remain warmer where cloud cover is more abundant,
which is likelier along the Southwest coast and for the Kuskokwim
Delta.

For the Bering Sea and Aleutians, unsettled conditions return
through the end of the week, but remain rather benign. A pair of
weak lows are expected to along either side of the Aleutian Chain
from today into Friday, sending multiple rounds of rain showers
across the region from west to east. Winds will pick up slightly
as the initial low moves across the western and central Aleutians
from this afternoon through Thursday night. However, winds will
generally stay at or below 25 kts through Saturday. By this
weekend, the northern low weakens into a mess of disorganized
showers across the central Bering Sea, while the southern low
exits into the North Pacific, where it has potential to intensify.

CQ/AS

&&

.LONG TERM FORECAST (Sunday through Wednesday)...

Persistent longwave troughing broadly stretching from the Bering
Sea to Southeast Alaska keeps both the Southcentral and Southwest
regions of Alaska active through the long term period. Models are
in fairly good agreement to begin the long term with a potent
shortwave lifting north from the base of the trough into the Gulf
of Alaska. A large 980-990 mb surface low looks to peak in
intensity Monday morning as it enters the southwestern Gulf. Heavy
rain is expected along the eastern Kenai Peninsula and northern
Gulf coast Monday into Tuesday as the frontal system arrives to
the coast Monday morning. Gusty northerly winds across the Alaska
Peninsula on the backside of the low as well as the potential
development of a gale-force barrier jet outside of Prince William
Sound ahead of the front will be possible Sunday through early
next week. Light to moderate rain continues through the end of the
forecast period along the Gulf coast while showers spread across
inland Southcentral for Wednesday as the low progresses inland.

Multiple rounds of shortwave energy propagating from the
Kamchatka region across the Bering Sea will impact portions of the
Aleutians and Alaska Peninsula Monday through the end of the
forecast period. Some uncertainty in the track of the strongest of
these systems for early next week remains as models slowly come
into agreement with these weaker features. Elevated winds and
periods of rain may be expected across much of the Aleutians as a
low skirts along the south of the island chain and Alaska
Peninsula through Wednesday.

&&
.AVIATION...

PANC...Light northerly winds are forecast through the period as
an upper trough sits just south of the Kenai Peninsula. Despite
much of the moisture getting downsloped by the Chugach Range,
ceilings have bounced between VFR and IFR through much of the
day. Rain chances will persist through Thursday morning with
predominantly VRF ceilings. However, ceilings may occasionally
dip to MVFR or even IFR levels at times, especially through the
overnight and early morning hours.


BL

&&


$$