Gale Warning 165, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
655 AM AKST Thu Feb 13 2025

.Update...to include information about low ceilings and fog
potential for this morning at PANC in the aviation discussion.

&&

.PREV DISCUSSION... /issued 413 AM AKST Thu Feb 13 2025/

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

The pattern begins to shift as a trough tracks into Southcentral
out of the Yukon and a North Pacific low moves into the Gulf of
Alaska. Relatively dry conditions will continue for much of
Southcentral today ahead of the trough, though clouds will move in
from east to west through this evening. Areas with the highest
chance for precipitation will be from Prince William Sound east to
Cordova, including Valdez and Thompson Pass, by tonight as the low
tracks towards the north Gulf coast. Cold air filtering in will
allow for increased wind speeds through Thompson Pass which may
result in periods of blowing snow. Elevated winds to gale force
are also expected offshore along the north Gulf coast tonight as
the front moves through. The models are... optimistic about
chances for light snowfall for Anchorage, Kenai and the Mat-Su
Valleys. However, with dry air in place and no significant push
of moisture to replace it, if snowfall does occur, it will be
flurries or very light snowfall on Friday morning. The Susitna
Valley will have the highest chances for snowfall due to upslope
flow.

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

Aside from a few minor changes, the forecast remains largely on
track. Generally, expect a cooldown across the region, with
unsettled conditions for the Aleutians/Bering and cold, breezy
conditions for Southwest Alaska. The forecast for today may
continue to shift as weak storms meander across the Bering Sea,
with minor model disagreements on how exactly these features will
interact with each other. A gale force front moves into the
Western and Central Bering/Aleutians by Friday, bringing more
active weather. Beyond about Friday evening, forecast confidence
diminishes as models try to hone in on where lows will develop
along this front, and how these lows will evolve. Overall, the
primary hazards to watch for will be wind chills in the negative
twenties from tonight through Friday afternoon, as well as heavy
to perhaps even extreme freezing spray off the Kuskokwim Delta
coastline and in the northern Bering Sea.

-Chen

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

The Alaska Weather map is becoming busy synoptically through the
forecast period. An upper level trough weakens and moves out of
the Gulf of Alaska for Monday. It is followed by a weak ridge
moving across from the Aleutians and Bering that will set up over
Southeastern Alaska through midweek. A broad upper level trough
slides in from the Russian Far East to the South of the Aleutians
before changing track to move into the Bering by Wednesday. This
trough supports more active weather across the entire Southern
portion of the state through Wednesday. A blend of ECMWF / GFS and
Canadian models carry the features well through most of the
forecast before greater amounts of uncertainty bleeds in for the
end of the period.

A well developed surface low in the Eastern North Pacific extends
a front from Kodiak Island across across the Southcentral coasts.
A second front follows and extends the active rain area Westward
over the Aleutians and Alaska Peninsula, with another round of
moderate rain across the Southcentral coasts. Areas of snow are
expected further inland for Southcentral and over higher terrain.
This system spreads snow over the Bering and Southwest Alaska
Monday and Tuesday before reaching St Matthew and Nunivak Islands
for Wednesday.

- Kutz

AVIATION...

PANC...Ceilings are lowering over portions of Anchorage this
morning. Fog development will likely remain in the vicinity this
morning through around 22Z, but visibility reductions over the
terminal are expected to be brief and periodic. Otherwise, calm
and clear conditions will persist through this afternoon. By this
evening, increasing mid-level cloud cover will develop and overnight
into early Friday morning, low-level moisture will increase, with
high confidence for MVFR ceilings and the potential for reduced
visibility. Confidence remains low on whether any light snowfall
will reach Anchorage by Friday morning. If it does, accumulation
would be very minimal, with flurries or very light snowfall
possible.

&&

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>