Gale Warning 94, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
832 PM AKST Wed Jan 22 2025

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3:
Tonight through Saturday Night)...

Scattered showers tonight, in addition to a rather quick-moving
storm tomorrow, will bring the potential for additional
precipitation accumulations. A Winter Weather Advisory is now in
effect for northern Susitna Valley as Thursday's storms will
bring heavy snow to the region. Otherwise, this will truly be the
calm before the storm as a warm and incredibly wet series of
atmospheric rivers sets its sights on Southcentral. A Hydrologic
Outlook is currently in effect for Kenai Peninsula, Anchorage, and
Mat-Su in anticipation that temperatures in the high 30s/low 40s
and prolonged, moderate to heavy precipitation could lead to
flooding. We will be closely monitoring this storm system, and we
urge you to stay tuned to the forecast and prepare accordingly.

Diving into the details... the forecast for tonight and tomorrow
remains largely on track. Showers will gradually taper off, with
the bulk of additional accumulations tonight focused along
northern Susitna Valley, the Talkeetna Mountains, and Prince
William Sound. A surge of cold air moving in tonight will help
prime conditions for some rain/snow mix or even snow as a robust
shortwave sweeps across Southcentral beginning late tonight/early
tomorrow morning. However, temperatures tomorrow have trended
warmer, making it more likely that most areas will see a rain/snow
mix rather than all snow. This has decreased our concern for
heavy snow in the Homer Bluffs, though temperatures will stay cool
enough for the northern Susitna Valley to accumulate about 8-12
inches through the course of tomorrow.

Looking ahead, Friday and Saturday continue to be when the most
impactful weather is expected. As mentioned above, we're
anticipating a trend towards warmer and much wetter conditions,
with the potential for moderate to heavy precipitation to persist
through most of the weekend. All but deep interior Copper River
Basin will likely see precipitation at some point. It's a bit
early right now to give detailed precipitation estimates, but
liquid precipitation amounts from Friday through Saturday could be
somewhere in the range of 1-3 inches, with the greatest amounts
along Eastern Kenai Peninsula, Prince William Sound, northern
Susitna Valley, and southern Kodiak Island. Most communities and
areas along the road network will likely see this precipitation
falling primarily as rain, with the exception of higher elevation
locations like Broad Pass, Isabel Pass, and Thompson Pass. In
addition, a tightening pressure gradient will lead to gusty
southeasterly winds through Turnagain Arm/Anchorage, Palmer, and
the Copper River Basin. Stay tuned for forecast updates as we
could see fairly impactful weather from Friday into the weekend.

-Chen

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 3)...
The active weather pattern continues for the southwest Mainland as
a low pressure system over the Bering Sea sends a front overhead
Wednesday evening. The front will bring a mix of rain and snow,
with rain more likely toward coastal areas and better chances for
snow inland. Gusty southerly winds will accompany the front with
gusts in the 30 to 40 mph range for the Kuskokwim Delta behind the
front late Wednesday night into Thursday morning. A coastal flood
warning has been issued the the Kuskokwim Delta due to these
conditions. While there will be an initial surge of water this
evening around 3 feet above mean high high water, the bigger
impact will likely Thursday evening into Friday morning with the
next system.

Quick on the heels of the first front, a second system pushes into
the central Bering Sea. The front with this system has a much
warmer air mass and a better chance for much of the Mainland to
see rain as the predominant precipitation type. Southerly winds
will be stronger as well, with gusts reaching as high as 50 mph.
There are better chances for coastal flooding for this system as
well as a surge of water up the Kuskokwim River making overflow
conditions possible, see the special weather statement for more
information.

Looking farther ahead to the weekend, yet another disturbance and
front impacts the area, this one brings the possibility of
accumulating snowfall for the Kuskokwim Delta with rain for
Bristol Bay and the Kuskokwim Valley. Stay tuned!

MTL

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 through 3)...
The prevailing storm track remains from the north Pacific into the
Bering Sea through the weekend. The upcoming system on Thursday
will bring storm-force winds to much of the central and eastern
Bering Sea. There is a chance for some hurricane force gusts
closer to the Fox Islands. Another front and low pressure system
moves into the eastern Bering Sea on Saturday, this one with a
weaker wind field, however, behind this system, arctic air will
bring a much colder air mass to the area which will return
freezing spray concerns for much of the Bering Sea as well as a
possibility of a polar low with strong/compact winds on Saturday.

MTL

&&

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

Key takeaways:

	- High southerly winds and heavy precipitation shifts away from
   the southern coast towards the Panhandle
	- Heavy snow totals across the Brooks Range, Kenai Peninsula and
   higher elevations of South Central will start to taper off
	- Significant pattern shift to bring much colder temperatures
   across the forecast area early in the work week.

A strong northeast Pacific high coupled with a strong upper level
shortwave trough and surface low will produce strong gradient
winds across the Aleutians through the Alaskan and Kenai
Peninsulas early in the period. The Pacific high pressure will
start to retreat eastward allowing for an upper level long wave
trough to migrate over much of the state on Monday through the end
of the period as a moderately strong ridge of high pressure moves
into the western Bering sea.

The southerly winds and and heavy precipitation, across the
mainland and AKPEN, will start to abate on Sunday evening as an
arctic airmass moves over much of the state. This air mass will
linger through the end of the forecast period bringing northerly
winds and much colder, below normal temperatures across the state.

-DD

&&

.AVIATION...

PANC... Scattered rain showers will diminish through this evening
with primarily VFR ceilings lowering to MVFR ceilings overnight.
Southerly to southwesterly winds prevail through Thursday
evening. Wind gusts range from 20 to 30 knots later this evening
into Thursday evening. Precipitation moves back into the area
after 10Z and is expected to stay rain or a rain-snow mix through
mid to late morning.

&&

SPECIAL WEATHER STATEMENT
National Weather Service ANCHORAGE AK
1147 PM AKST Wed Jan 22 2025

AKZ155-240200-
Kuskokwim Delta-
Including the cities of Bethel and Nunivak Island
1147 PM AKST Wed Jan 22 2025

...STORM SURGE TO BRING POSSIBLE OVERFLOW TO LOWER KUSKOKWIM
RIVER THIS AFTERNOON INTO EARLY FRIDAY MORNING...

Southerly winds will ramp up this afternoon (Thursday) with gusts
to 40 to 50 mph. A Coastal Flood Warning is in effect for storm
surge for the Kuskokwim Delta. As the surge pushes into the mouth
of the Kuskokwim River, there is the possibility for impacts up
the river. Ice thickness is likely enough that flooding should not
be a concern with this system, but any holes in the ice will be
prone to overflow from underneath. Standing water on the ice will
make travel difficult and mask ice conditions on the surface.
Conditions will improve through day on Friday as gusty southerly
winds diminish and turn southwesterly. Keep updated on ice
conditions with local resources.