Storm Warning 148, NWS Anchorage, AK

248 
FZAK61 PAFC 210116
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
416 PM AKST Thu Nov 20 2025

Offshore waters forecast for the Gulf of Alaska West of 144W

Wind forecasts reflect the predominant speed and direction
expected. Sea forecasts represent an average of the highest
one-third of the combined wind wave and swell height.

PKZ399-211445-
416 PM AKST Thu Nov 20 2025
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 958 mb low at 59N 152W moves to 59N 149W at 974 mb tomorrow 
morning before moving over the E Kenai Peninsula tomorrow evening. 
Weak troughing lingers in the Gulf of Alaska through Sat.

$$

PKZ351-211445-
Gulf of Alaska Offshore North of 57N and West of 144W-
416 PM AKST Thu Nov 20 2025

...GALE WARNING THROUGH FRIDAY...

.TONIGHT...SW wind 30 to 40 kt. Seas 22 to 28 ft. Rain showers.
.FRI...SW wind 30 to 40 kt diminishing to 20 to 30 kt in the
afternoon. Seas 15 to 21 ft.
.FRI NIGHT...SW wind 10 to 25 kt. Seas 11 to 16 ft.
.SAT...W wind 15 to 25 kt. Seas 10 to 14 ft.
.SAT NIGHT...W wind 10 to 20 kt. Seas 7 to 12 ft.
.SUN THROUGH TUE...SE wind 15 to 30 kt. Seas 4 to 9 ft.

$$

PKZ352-211445-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
416 PM AKST Thu Nov 20 2025

...GALE WARNING THROUGH FRIDAY...

.TONIGHT...SW wind 25 to 40 kt. Seas 19 to 28 ft.
.FRI...W wind 20 to 35 kt. Seas 17 to 20 ft.
.FRI NIGHT...W wind 15 to 25 kt. Seas 14 to 17 ft.
.SAT...W wind 20 to 30 kt. Seas 12 to 17 ft.
.SAT NIGHT...W wind 10 to 20 kt. Seas 9 to 14 ft.
.SUN THROUGH TUE...SE wind 20 to 35 kt. Seas 6 to 11 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
438 PM AKST Wed Nov 19 2025

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 2)...

While much of the fog is finally dissipating this afternoon,
localized areas continue to impact portions of Southcentral this
afternoon from the Mat-Valley down through the Anchorage Bowl and
into the western Kenai Peninsula. Southcentral remains wedged
between competing weather systems with high pressure between the
two systems and a warm air inversion unwilling to let go of
regional fog entirely. The expectation is for winds to increase
over Southcentral through tonight, as a Gulf low sends an easterly
wave into the Sound through tomorrow morning and a second low
over the Aleutians lifts into Cook Inlet. Winds be strongest over
the Eastern Turnagain Arm and also through Palmer and Wasilla
where a Mat-Valley wind should gust as high as 30 to 35 mph for
much of Thursday. The increasing winds will help remove any
lingering fog while also bringing in warmer temperatures. The
biggest challenge then in the short term is precipitation and
precipitation type.

A quick round of a wintry mix will accompany the easterly wave
tonight across the Chugach Mountains into Turnagain Pass and
possibly into the Anchorage Bowl. Accumulations at the surface
will be on the light side most locations only seeing a dusting,
though up to 1 to 3 inches is possible along the Seward Highway
from near Portage down through Turnagain Pass, Moose Pass, and
Cooper Landing, transitioning to light mixed precipitation as snow
levels rise. Roads could become slick through the morning hours.
Downsloping winds over the Chugach Mountains should limit heavier
precipitation to the Gulf Coast and Prince William Sound tonight
and tomorrow, though the arrival of a low over the Alaska
Peninsula into Cook Inlet will help moisture lift further
northward into the Copper River Basin Thursday afternoon. Thompson
Pass will likely remain all snow with a good 8 to 12 inches of
snow accumulation forecast through Thursday night. Meanwhile, only
an inch to perhaps 2 inches are forecast from Sutton to Mendeltna
along the Glenn Hwy corridor.

Any precipitation that does fall further inland across
Southcentral should be relatively light, with sprinkles being the
likely outcome tomorrow morning for the Anchorage Bowl north into
the Valley. It does appear that a brief window of freezing rain
and a freezing rain/snow mix will develop across the Western Kenai
Peninsula, Anchorage Bowl, and Mat-Valley during the morning
hours on Thursday. Again, however, precipitation amount should be
extremely light with little to no accumulations forecast as snow
level rise to ~2000 ft. Slick road conditions, however, may be
present during Thursday morning's commute.

Temperatures will continue to warm into the latter half of
Thursday with daytime highs in the mid to upper 30s and the
potential for some locations to see low 40s with the gustier
winds. By Thursday afternoon precipitation should be largely all
rain, and then, just as quickly as temperatures warmed, cold air
advection on the backside of a departing low into interior Alaska
should see temperatures cool and snow levels drop back to the
surface Thursday night through early Friday. On Friday yet another
trough is forecast to push into Southcentral and light snow
chances will return to the region before temporary high pressure
develops on Saturday with drier conditions and a break from
unsettled weather.

BL

&&

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

Today's chapter of the Southwest Alaska, Bering Sea, Alaska
Peninsula (AKPEN), and Aleutian Chain starts with two lows in the
Bering Sea; one in the western Bering and one in the eastern
Bering. The low in the western Bering will deliver gusty winds and
showery conditions across the Western and Central Aleutians today.
This low will usher in a colder airmass across the Bering as it
dives southward into the North Pacific by then.

The low in the eastern Bering, currently just north of the
Pribilof Islands, will continue north to between St. Matthew and
St. Lawrence Islands by tonight. Its front will move into the
mainland Southwest coast through today. Initial snow over Nunivak
Island and Nelson Island will turn to rain/snow mix as the morning
progresses with warmer air working in with the gusty southeasterly
winds. Snow accumulations across Nunivak Island and Nelson look to
be light this morning before rain mixes in. Bethel will stay
mostly dry due to strong southeasterly downsloping off the
Kuskokwim Mountains. However, scattered rain and or rain/snow mix
showers could make it over the mountains this afternoon as flow
will turn more southerly.

A North Pacific low, currently between and south of the Central
Aleutians and Eastern Aleutians, continues gaining strength today.
This low will make it to near the southern AKPEN by this evening
and will deliver strong gusty southeasterly winds through the
AKPEN and into southern Bristol Bay. Gusts in the near coast zones
south of Kodiak Island will be around 55 kts tonight and same for
southern Bristol Bay. Of more concern is how this low and
associated upper-level shortwave will interact with the shortwave
currently responsible for the active weather across the Kuskokwim
Delta Coast and Kuskokwim Delta this morning. In addition to
strong gusty winds along the southern AKPEN, heavy rain is likely
starting this afternoon and lasting into tonight. The heaviest
rain corridor looks to be between southern Kodiak Island and Sand
Point, which includes Perryville and Chignik.

A band of moderate to heavy precipitation will setup along the
western Bristol Bay Coast, from the Western Capes to Togiak,
later this morning with the front of the eastern Bering low moving
in. Most precipitation this morning is expected to be rain. As the
North Pacific low moves to the southern AKPEN tonight winds shift
from southeast to east or even east-northeast. Precipitation along
the Bristol Bay Coast and into Inland Bristol Bay becomes moderate
to heavy at times. Due to intense precipitation rates, cold air
aloft looks to be brought down to the surface. Therefore, rain
today will eventually change over to wet snow this evening across
the Bristol Bay Coast and Inland Bristol Bay. Snow may fall
heavily at times tonight. Temperatures will be near freezing
tonight through Thursday. With that said, a Winter Weather
Advisory has been issued for the Bristol Bay Coast, including
Dillingham and Togiak, as well as inland Bristol Bay, including
Koliganek, New Stuyahok, and Aleknagik from 6PM this evening to
6PM Thursday evening. 4 to 8 inches of snow is expected with
locally higher amounts possible, especially along the Ahklun
Mountains. With the antecedent airmass being marginal when it
comes to cold air, precipitation rates will be vital to the
forecast. There is potential for more snow accumulation if heavier
bands set up and persist. However, and conversely, if
precipitation does not fall too heavily, the warmer air could win
out with rain mixing which would lower snow totals. The forecast
and the products reflect a middle ground.

Cold air moves back in across Southwest behind this low on Friday.
Winds will be northerly along the Kuskokwim Delta Coast with snow
showers moving across Nelson Island and Nunivak Island from the
Bering. Blowing snow and reduced visibility are possible Friday
along the mainland coast, and the AKPEN. Another front and low
approaches the Western Aleutians for Saturday as snow showers
continue along the AKPEN. Snow showers across Southwest for
Saturday will remain mostly confined to the mountain ranges. Stay
tuned for further forecast updates, especially regarding the
evolution of the North Pacific set to impact Southwest tonight and
Thursday.

&&

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

An omega block pattern will be in place at the start of the long
term forecast period with a dying low in the Gulf of Alaska,
building high pressure over the Bering Sea, and another low just
south of the western Aleutians. The tight pressure gradient
between the Bering high and Aleutian low will create a corridor of
southerly winds up to storm-force through the western and central
Aleutians Saturday night and Sunday. The low will track into the
Gulf of Alaska for the first half of the week, setting up a rex
block pattern with high pressure over the northern half of
mainland Alaska and low pressure over the southern Alaska and the
Gulf. Surface lows spinning up will likely bring elevated winds
and precipitation to the Bristol Bay region, Kodiak Island, and
the north Gulf coast Tuesday and Wednesday while the Copper River
Basin and interior Alaska stays cold and dry.

&&

.AVIATION...

PANC...For this afternoon and evening, the potential for fog will
persist. However,a strong front will push into the coast tonight,
but downsloping should keep the area dry and VFR. Northerly winds
will also increase through the TAF period as a low pressure
system approaches the Alaska Peninsula this evening and the
southern Inlet Thursday morning. Wind shear is not expected at
this time due to the strong down- inlet winds, but strong
southeasterly winds are expected above 3000 to 4000 ft.
Thursday has to potential to see a mix of precipitation-types that
will be strongly dependent on the exact track the low takes up
Cook Inlet late Thursday into Thursday night.

&&