018
FXAK68 PAFC 281438
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
538 AM AKST Fri Feb 28 2025

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

The leading front of a broad low in the north Pacific has moved
onshore this morning, with peak winds observed over the marine
areas around 50 to 55 kts. Stratiform precipitation has become a
little more showery in appearance along the coast, where
persistent rain and upper elevation snow will continue today. For
lee-side areas, a shortwave moved through early this morning,
leading to a mixture of precipitation types from the western Kenai
north to Anchorage. Another such shortwave will move through
later today, for another round of rain, graupel and possibly snow
showers. This front has nudged most of the cool air out of the
region, so temperatures over the next 48 to 72 hours will approach
or exceed 40 degrees for many areas.

Moving into Saturday the low will quickly weaken and push into
the eastern Gulf, bringing a brief respite in precipitation along
the coast. However, the pattern will remain active and amplified,
with a shortwave and ill-defined surface low driving from the
North Pacific into Southwest Alaska, with a front moving into the
Sound on Sunday. Most of the precipitation will be confined once
again to the Sound with downsloping winds keeping the lee-side
areas dry, but should the upper level shortwave trend to the east,
some light spillover is possible. By Monday, the ridge building
over British Columbia will begin to strengthen into the Yukon and
interior of Alaska, which will allow the next few storms to slide
into the Gulf from the west. The ridge may help to keep things
drier for a day or two along the coast.

-CJ

&&


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

Synoptically, a North Pacific Low moves northeastward toward the
Gulf of Alaska today, a front continues to move through the
AKPen/Bristol Bay areas through this evening, northerly flow
persists through the Bering Sea into the weekend and another low
moves toward the Central Aleutians/AK Pen late this weekend.

Waves of moisture brought snow over the Bristol Bay area last night
and through this morning. Surface observations, radar and
satellite show low visibility, light snow and persistent waves of
moisture moved through the area during this time. Additional
light snow continues through tomorrow morning accumulating up to
an additional two inches from Aleknagik to Koliganek northward.

Northerly to northwesterly winds in the Bering Sea continue to
cause low clouds and convective snow and rain showers from Akutan
to Port Heiden. Precipitation will wane throughout the day before
ending late this afternoon. Precipitation continues east of Port
Heiden into the evening hours. Intermittent low visibility during
these showers can be expected and Eastern Aleutians gap wind
speeds as high as 35 knots are likely through late this evening.

Tomorrow, a fast-moving low from the North Pacific brings rain
and snow to the Central Aleutians tomorrow afternoon. After
crossing the Aleutians, it moves northeasterly toward the SWAK
mainland. Though differences exist to where it makes landfall
along the SWAK coast, precipitation will fall from Dillingham to
Koliganek northward to Bethel and Aniak as snow this weekend where
snowfall accumulations ranging from 3 to 6 inches from late
Saturday evening through early Sunday morning are probable.
Additionally, patchy fog is expected in the AK Pen, portions of
the Aleutians and Kuskokwim Delta this weekend from this storm.

-DJ/BS

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

The upper level ridge extending over Southeast Alaska and Western
Canada across Interior Alaska weakens and slips further into the
Canadian Provinces through midweek. An upper level North Pacific
low pushes into the Gulf of Alaska and dissipates into a trough
for Wednesday. Working its way out of the Russian Far East, a well
developed upper low marches over the Aleutians to the Alaska
Peninsula by Thursday. There is decent continuity with an ECMWF /
GFS / Canadian cluster with the larger scale features that yields
to an ensemble blend by the end of the forecast period. Highest
uncertainty rests in the smaller details working through the
pattern with shortwaves supporting surface weather.

Cold air pools over the Bering with the broad trough, while warm
air ahead of the low continues to pump over the Southcentral
coasts into the Interior. The forecast opens Monday with a
decaying front spreading locally moderate rainfall along the
coasts from Kodiak Island to Prince William Sound for Monday.
Areas of snow over Southwest Alaska slip to the West through
Thursday. A moderately strong North Pacific surface low and front
brings another round of rain from the Alaska Peninsula and Kodiak
Island to Southcentral Alaska to the Copper River Delta Tuesday
through Tuesday. Areas of snow moves out from this low over
Bristol Bay and Southwest Alaska. A well developed North Pacific
low and front Monday marches over the Aleutians, AKPEN, Southwest
Alaska all the way into Prince William Sound through Tuesday,
weakening somewhat for Wednesday over the Copper River Delta.
Locally heavy precipitation is expected along the Eastern Kenai
Peninsula and Southcentral Alaska Wednesday into Thursday.

- Kutz

&&



.AVIATION...

PANC...VFR conditions and light northerly winds will persist.
Southeast prevailing flow aloft will generally keep conditions
dry, but periodic light sprinkles or flurries will still be
possible at the terminal as weak shortwave troughs move north into
the Mat-Su from the Gulf through this afternoon. The core of
stronger southeast winds aloft is expected to stay far enough
above the surface to avoid supporting any notable LLWS concerns at
the terminal throughout the TAF period.

-AS

&&


$$