Gale Warning 55, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
440 PM AKST Sun Jan 7 2024

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

A frontal boundary is stretched across the Southcentral coastline
and is bringing a rain/snow mix to to coastal cities and just
snow to locations further inland. At the time of writing this,
snow is ongoing as the axis of the front is oriented from Whittier
to Kenai, and is shifting northward steadily today. Temperatures
near sea-level remain marginal, with many locations such as
Whittier and Seward seeing occasional shifts between rain and
snow. Temperatures are fluctuating near freezing in these
locations and it complicating the forecast of how much snow will
actually accumulate at the surface. For the locations further
inland such as Kenai, Soldotna, and eventually Anchorage up to the
Mat-Su Valleys, precipitation is expected to come down mainly as
snow with the passage of this system tonight, however some light rain
is possible before the front passes through.

Along the eastern Kenai Peninsula, the period of strongest
precipitation has passed and is expected to continue, however ease
significantly overnight tonight. A minor wave rotating about the
backside of this front will move into the Eastern Kenai Peninsula
early Monday afternoon, bringing another burst of snow, with half
an inch of accumulation possible for places such as Whittier and
Seward. This secondary wave does not have the support to break
through into the interior of Southcentral and while places near
Moose Pass may see below half an inch of new snow, from Cooper
Landing east and from Girdwood north, no additional snowfall is
anticipated.

A Winter Weather Advisory remains in effect until midnight
tonight for the eastern Kenai Peninsula where one to two feet of
snow are possible for parts of Turnagain Pass to the Hope Cutoff
and south toward Summit Lake. Lesser amounts are expected
elsewhere, where temperatures in the mid 30s will limit any snow
accumulation.We have received reports of standing water along
portions of the Seward highway near eastern Turnagain Arm. Likely
cause of this is the near freezing temperatures in conjunction
with the rain/snow mix in the area persisting.

Light snowfall has begun in Anchorage this afternoon, and from
Kincaid to the Hillside, we will likely see about 3 inches of
snowfall, with some higher amounts along the hillside potential.
Warmer locations such as Eagle River and the Matanuska Valley have
reported a mix of rain and snow this afternoon. The period of
strongest snowfall rates will be from around 6pm to 9pm AKST this
evening as the front passes. Snowfall in Anchorage will diminish
quickly afterwards, coming to an end by Midnight tonight. The onset
of snow will begin early this evening for the MatSu Valleys as
well with less snowfall than the Anchorage area expected. 1 to 3
inches are possible through the Palmer and Wasilla areas, and less
further north along the Parks Highway. Glennallen may see some
light snow accumulation late tonight as the front pushes
northward, dropping a few tenths of an inch, but the cloud cover
will help keep the overnight temperatures from dipping as cold as
they have been.

By Monday evening, Southcentral will be entering a fairly quiet
period, as weak ridging looks to move in beginning Tuesday. This
will provide a break from the active weather across the
Southcentral coastline, but may lead to some colder overnight
temperatures in the Copper River Basin. We will continue to
monitor the active weather pattern, and look forward to the
potential break.

-CL

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (Days
1 through 3...

A large upper low taking up real-estate over the Bering Sea is
finally beginning to track further northward this evening. At the
surface a weakening 957 mb low has moved east of Saint Matthew
Island this afternoon and is forecast to move into Northeast
Russia through Monday morning. Winds across the Kuskokwim Delta
remain elevated, with gusts to 35 mph from Mekoryuk to Bethel.
Isolated to scattered snow showers may persist intermittently into
Monday, but weak high pressure will build over the Bering Sea
temporarily on Monday resulting in calmer winds and drier
conditions over Southwest Alaska. The winter weather advisory for
the Lower Kuskokwim Valley was allowed to expire earlier this
afternoon as snow finally came to an end.

Offshore, current seas range from 15 to 25 feet for much of the
Bering. Winds across the Pribilof Islands remain elevated with
persistent gusts to 45 knots. Visibility has bounced between a
half mile and 3 miles, but should improve through the evening
hours. As the upper low finally weakens and departs to the north,
seas will gradually decline through the overnight hours with seas
ranging from 10 to 15 feet by midday tomorrow. The next upper low
moves into the Bering late Tuesday and Tuesday night. This third
in a series of Bering Sea lows is expected to be weaker than its
predecessors. The strongest winds will remain along or on the
Pacific side of the Aleutians, with westerly gales on the backside
of the low and southerly gales gusting to storm force across the
Eastern Aleutians ahead of the low. In particular, Nikolski would
be most vulnerable to the onshore flow. On another note, but
somewhat related, strong southerly flow will bring a wedge of
warmer temperatures into the southern Bering along with another
mix of rain and snow through Wednesday. Further ahead of the low,
a front should reach the Southwest Coast Wednesday morning with
any initial snow potentially transitioning to rain.

The only concerns for Southwest Alaska will be for potential snow
and blowing snow over the Kuskokwim Delta as the front clips the
coast with stronger easterly winds and a quick round of light to
moderate snow. Timing, if an advisory is needed, would be sometime
from Tuesday night into Wednesday morning. The evolution of the
low and its front will be monitored closely over the next 24 to 36
hours.

BL

&&

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

The main long-term weather feature will be an upper level ridge
over Southwest Alaska that builds through Thursday afternoon.
This will maintain the general storm track over the western Bering
through Friday, when an upper level trough from a Bering low
sweeps northward across Southcentral. There are early indications
that a second low from the north Pacific will quickly cross the
Aleutian Chain and merge with the Bering low. This new system
forms an upper level trough which slides over Southcentral on
Saturday. Lower level features of the two lows appear to merge and
slowly track north along the western coast, while an extended
moisture fetch trailing the north Pacific low continues into
Southcentral and the northern Gulf late Saturday.

&&

.AVIATION...

PANC...MVFR conditions will quickly transition to IFR conditions
this evening as a strong front moves north through Cook Inlet.
There could be a few hours of heavier snowfall with nearly 1 inch
per hour rates in the 3Z to 6Z time frame (6 PM to 9 PM local)
this evening. This snow is expected to bring in IFR visibility and
IFR or lower end MVFR ceilings. After midnight, the snow should
taper off as southeasterly winds out of Turnagain Arm will push
into the airport. This will improve the visibility back to VFR
though MVFR ceilings may linger over the airport through the
morning Monday.

&&

Preliminary Local Storm Report
National Weather Service Anchorage AK
1109 PM AKST Sun Jan 7 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0807 PM     Snow             Rabbit Creek            61.07N 149.77W
01/07/2024  M2.3 inch        Anchorage          AK   Public

            As of 8pm, 2.3 inches of so far, still
            snowing steady at a moderate rate.

&&

KM

Preliminary Local Storm Report
National Weather Service Anchorage AK
1117 PM AKST Sun Jan 7 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0913 PM     Snow             Upper Hillside          61.12N 149.71W
01/07/2024  M5.0 inch        Anchorage          AK   Public

            Steady snowfall, total snow accumulation as
            of 9pm 5.0 inches 28F Slight winds
            Visibility estimation less than 0.5 mile.

&&

KM

Preliminary Local Storm Report
National Weather Service Anchorage AK
1119 PM AKST Sun Jan 7 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1029 PM     Snow             Rabbit Creek            61.07N 149.77W
01/07/2024  M5.3 inch        Anchorage          AK   Public

            as of 10:30pm, snow rates slowing down. 5.3
            inches measured so far.

&&

KM

Preliminary Local Storm Report
National Weather Service Anchorage AK
1120 PM AKST Sun Jan 7 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1045 PM     Snow             Abbott                  61.14N 149.82W
01/07/2024  M5.3 inch        Anchorage          AK   NWS Employee

            5.3 inches as of 10:40pm. Most of it fell in
            2:15. Large low density aggregates.

&&

KM

SPECIAL WEATHER STATEMENT
National Weather Service ANCHORAGE AK
307 AM AKST Mon Jan 8 2024

AKZ102-112-081315-
Anchorage-Matanuska Valley-
Including the cities of Anchorage, Eagle River, Indian, Eklutna,
Palmer, Wasilla, Sutton, and Chickaloon
307 AM AKST Mon Jan 8 2024

The widespread moderate to heavy snow has come to an end for
Anchorage and the Matanuska Valley.

Preliminary Local Storm Report
National Weather Service Anchorage AK
343 AM AKST Mon Jan 8 2024

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1155 PM     Snow             E Butte                 61.53N 149.01W
01/07/2024  M3.4 inch        Matanuska-Susitna  AK   Public

&&

KM