Gale Warning 149, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
644 PM AKST Fri Feb 7 2025

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

High pressure remains the dominant feature for Southcentral,
excluding Kodiak Island, through Monday. A front brings rain/snow
to Kodiak Island and coastal eastern Kenai Peninsula late this
weekend and into the beginning of next week.

High cirrus clouds over parts of the Copper River Basin and Mat-
Su Valleys this morning have drifted southeastward over Prince
William Sound and portions of the Kenai Peninsula this afternoon.
A dry atmosphere will keep cloud cover to a minimum and wind
speeds very calm through the weekend as the high strengthens and
moves southeastward over most of Southcentral. Though patchy fog
forms overnight across the Copper River Basin and portions of the
Kenai Peninsula, it will remain not as thick as in previous
nights.

A front currently impacting SW Alaska and the Aleutians
today brings increased cloud cover as early as late this evening
to Kodiak Island including the City of Kodiak. Models have been
quick to bring precipitation associated with this front to the
City of Kodiak however forecaster experience and pattern
recognition has led to a slower progression of the onset of
precipitation until early tomorrow afternoon. Additionally, the
precipitation intensity will remain light snow through the late
afternoon hours before mixing with rain and changing to all rain
by the evening. This precipitation will move into the Kenai
Peninsula Sunday as a widespread mix of sea level rain/snow and
high elevation snow by the evening hours.

-DJ

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (Days
1 through 3: Friday afternoon through Monday Morning)...

A blocking ridge of high pressure remains anchored over the
Southwest mainland and far-eastern Bering, but is being nudged
slightly eastward as a large and elongated upper low over the
western Aleutians propagates north and east. This ridge has kept
conditions stable with clear skies, calm winds and cool
temperatures across Southwest Alaska, with areas of fog and low
stratus persisting.

Meanwhile, the western and central Aleutians, as well as the
Pribs, continue to see rain and gale-force winds as a north
Pacific surface low and its associated front continue north
across the chain. Tightened pressure gradients have brought gusty
winds to the Aleutians, portions of the Alaska Peninsula, and the
Pribs with sustained winds over 30 mph and gusts to about 50 mph
since the morning hours. These winds should ease by Saturday
morning as the surface low pulls north and out of the Bering;
however, by this time, the persistent gales will have helped to
usher the blocking ridge eastward, clearing the Bering by
the morning, in concert with the diminishing winds.

The active pattern continues across the Bering as a storm-force
North Pacific low drives a powerful front into the western
Aleutians by early Sunday afternoon. This system will rapidly
spread gale-force winds across the entire Bering and Aleutian
chain, also affecting the Southwest Coastline through Monday.
Meanwhile, a surface low tracking into the Alaska Peninsula is
still progged to cross Sunday night, however seems to have lost
some of its energy. As it interacts with the large and stretched
out frontal boundary of the storm-force low, winds along the
Kuskokwim and Bristol Bay coasts will be further enhanced. While
we continue to monitor the potential for coastal flooding,
particularly along the Kuskokwim Delta coastline, the general
consensus at this time is that the increased depth of shorefast
ice and the area of 90-100% ice coverage that further buffers the
coastline and extends into the Kuskokwim Bay may be enough to
limit any coastal flood hazard that would have affected the
coastline under these conditions otherwise. Warm air will arrive
with these systems, so precipitation will start out as a mix of
rain and snow before becoming all rain by Sunday afternoon. The
low swings north and west towards the Kamchatka Peninsula by late
Monday, leaving the blocking ridge in place, though further nudged
eastward.

AB/ME

&&

.LONG TERM FORECAST (Days 4 through 7: Tuesday Through Friday)...

Significant changes are expected over the Alaska Weather Map
through the forecast period. While most of the active weather
events continue to occur over the Aleutians and Bering, the upper
level ridge that held station with quiet weather over Mainland
Alaska is drifting into the Arctic. This allows an upper level
trough to extend from Western Canada over the Southern two-thirds
of Interior Alaska and sets up the formation of an upper level low
by Friday. The expansive upper low and trough over the Aleutians
and Bering continues to weaken, relaxing the synoptic gradient
across the Alaskan domain, which allows some North Pacific
influence to enter the region. The ECMWF / GFS / Canadian models
that carried the features yields to an ensemble mix by the end of
the forecast period.

A well developed Western Bering surface low weakens and withdraws
into Siberia. Its decaying front extends across the Northern
Bering to Southwest Alaska with locally moderate rain and gusty
winds through late Tuesday. A low moving along the front in the
North Pacific dissipates over the Alaska Peninsula Wednesday.
Locally heavy rain is expected over most of the AKPEN and Kodiak
Island through late Tuesday. Areas of snow develop over Southwest
Alaska and the Northern AKPEN through Friday. Weak lows quickly
develop and dissipate over the Western Aleutians and Southcentral
coast, spreading showers through Friday.

- KZ

&&

.AVIATION...

PANC...VFR conditions expected to continue through much of the
period; however, with high pressure remaining overhead, fog and
low clouds may redevelop over Cook Inlet by early Sat morning.
Otherwise, calm winds and largely clear skies to continue tonight
into Sat.

&&