Gale Warning 212, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
432 PM AKST Sat Feb 24 2024

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

A potent shortwave over the Kenai Peninsula and associated low
pressure just off the Southcentral coast continues light snow in
and near the Prince William sound through early tonight. Lingering
moisture and upsloping northwesterly flow will also allow snow
shower activity to continue along the Glenn Highway corridor and
Anchorage Hillside through early tonight.

As the low departs, strong cold air advection will allow gusty
northerly gap winds to develop. Gusts to 40+ mph are possible from
Seward to Whittier and Thompson Pass tonight through Sunday. With
the recent snowfall, this wind will likely produce areas of
blowing snow during this time, with these areas likely to see
significantly reduced visibilities at times.

Following this system a weak ridge will build ahead of a robust
upper level low over southwest Alaska. The associated parent low
in Bristol Bay will push its front over Kodiak Island into the
western Gulf Sunday night into Monday. With notable warm air
advection, this will likely be in the form of rain for much of
southern Kodiak Island, with a rain/snow mix in and near Kodiak
City. Models are then in good agreement on a triple point low
developing near Kodiak and the Barren Islands Monday afternoon,
but diverge in its track thereafter, which would determine the
inland extend of precipitation/snow along the Southcentral coast
through Tuesday afternoon. There is also the potential for snow
and blowing snow for northern Kodiak Island Monday night.
Regardless, areas of moderate snow are expected to make a return
to much of the immediate Southcentral coast Monday afternoon
through Monday night. Gusty winds are also expected to return to
the Mat Valley Monday morning into Tuesday afternoon as the flow
turns northeasterly as the triple point low develops.

-ME

&&

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

Latest satellite imagery depicts a North Pacific low and front
lifting across the Western and Central Aleutians this afternoon.
Scattered snow showers have been observed from Shemya to Adak.
While winds have been on the lighter side, easterly winds will
increase to small craft with gale force gusts tonight as the front
lifts into the Bering side of the Aleutians. The low remains
forecast to continue deepening through Sunday morning with a swath
of gales developing over the Pribilof Islands by midday. On the
south side of the low a second area of westerly gales will expand
in coverage, eventually overspreading the Central and Eastern
Aleutians through Sunday night. On Monday both Dutch Harbor and
Cold Bay could see westerly winds gusting into the 60 to 70 mph
range. Less confidence exists in winds reaching high wind criteria
at this time, especially with a less than favorable wind
direction, but conditions be monitored closely over the next 24
hours.

Pressing onward, the same low and front will lead to
deteriorating conditions across Southwest Alaska Sunday night into
Monday as well. Moderate to heavy snow is forecast for the
Greater Bristol Bay area along with winds gusting as high as 35
mph in some locations. This will result in a threat for blowing
snow and reduced visibility down to one half mile in addition to
total snow accumulations of 5 to 10 inches. A Winter Weather
Advisory is in effect for Bristol Bay from Sunday night through
noon Monday. A second Winter Weather Advisory is in effect for the
Kuskokwim Delta Coast from Sunday night into Monday afternoon.
Lesser snow accumulations of 3 to 6 inches will occur coincident
with northeasterly winds gusting from 30 to 45 mph. Snow and
blowing snow, with visibility reduced to one half mile, is
anticipated along the Kuskokwim Delta Coast from Kwigillingok up
into Toksook Bay and Mekoryuk.

-BL

&&

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

The mid to long range forecast looks to remain rather unsettled from
early to midweek with broad occluded low moving inland near Bristol
Bay and a more compact Kamchatka low that will begin to move into
the western Bering. A new triple-point low will develop near the
southern end of the Kenai Peninsula as the associated frontal
boundary lifts up across the Gulf. Models have this low rapidly
deepening before tracking it up the eastern side of the Kenai.
Strong gap flow winds will develop along the eastern Kenai and
Chugach Mountains in response. Easterly storm force winds also look
to develop along the northern Gulf coastal areas as pressure
gradient tightens along the the coastal mountains allowing barrier
jet to develop. Models and ensemble consensus also hint at modest
ridging building into the Bering by late in the week. The upcoming
week will also feature much colder temperatures as upper jet shifts
south and cold northerly flow dominates much of the Alaska mainland
and central Aleutians.

-PP

&&

.AVIATION...

PANC...Conditions will steadily improve in wake of a departing low
pressure. Can't rule out a few more snowflakes through this (Sat) evening,
but otherwise lifting and eventually clearing skies will result
in VFR conditions that will persist through Sunday. Wind will
remain generally less than 10 kts and out of the north throughout
the TAF period.

-Brown

&&

Preliminary Local Storm Report
National Weather Service Anchorage AK
947 PM AKST Sat Feb 24 2024

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

0750 PM     Snow             Rabbit Creek            61.07N 149.77W
02/24/2024  M6.2 inch        Anchorage          AK   Public

            A trained spotter measured 6.2 inches of
            snow. Still snowing.

0911 PM     Snow             Anchorage Hillside      61.12N 149.71W
02/24/2024  M7.0 inch        Anchorage          AK   Trained Spotter

            A trained spotter measured 7.0 inches of
            snow. Storm total.

&&

SPECIAL WEATHER STATEMENT
National Weather Service ANCHORAGE AK
1043 PM AKST Sat Feb 24 2024

AKZ195-260200-
Pribilof Islands-
Including the city of Saint Paul
1043 PM AKST Sat Feb 24 2024

...GUSTY WINDS COMBINED WITH PERIODS OF HEAVY SNOW FOR THE
PRIBILOF ISLANDS ON SUNDAY...

A low pressure system will extend its front across the Pribilofs
on Sunday, bringing periods of heavy snow and southeasterly winds
gusting up to 45 mph at times. Gusty winds combined with heavy
snowfall may reduce visibility down to one mile or less at times
due to blowing snow. The worst conditions will likely last a few
hours between Sunday around noon through late Sunday afternoon.
This system is expected to bring 3-5 inches of new snowfall to the
Pribilofs during this time. Low visibilities should start to
recover Sunday evening as the front passes, precipitation
lightens, winds diminish, and temperatures raise to or slightly
above freezing. By Monday morning, the low center will track over
the Pribilofs towards the Southwest Alaska coast, and winds will
become northerly. Cold air advection and elevated northerly winds
along the backside of the low may loft the previously fallen snow,
leading to periods of blowing snow and reduced visibility again
starting Monday afternoon.

Preliminary Local Storm Report
National Weather Service Anchorage AK
1157 PM AKST Sat Feb 24 2024

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

1013 PM     Snow             Eagle River             61.31N 149.48W
02/24/2024  M3.5 inch        Anchorage          AK   Trained Spotter

            A trained spotter measured 3.5 inches of
            snow. Storm total.

&&