Gale Warning 896, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
526 AM AKST Sat Nov 30 2024

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

Gusty winds out of gaps and passes are set to pick back up again
this evening into tonight as a front in the Gulf lifts northwards
towards the northern Gulf coast. The low east of Kodiak Island and
its associated front along with very cold temperatures in the
Copper River Basin will allow for a tightening gradient at the
surface sufficient for gusty winds in the commonly prone areas
such as the Copper River Delta, Thompson Pass, and the Matanuska
Valley Sunday morning into Monday morning. The overall strength of
the winds is expected to be marginal as an upper level low moving
southwest out of the Interior and into Southwest Alaska will
prevent any upper level support favorable for significant winds.
Meanwhile in the northern Gulf, a large swath of small craft winds
and areas of gale force winds in southern Cook Inlet, east of
Kodiak Island, and Shelikof Strait persist through Monday morning.

Ahead of the arrival of the front, a period of snow showers are
possible for the Eastern Kenai Peninsula Saturday night through
Sunday morning. As the front progresses towards the northern Gulf
coast by Sunday afternoon, models are not fully in agreement on
the track of the low creating some uncertainty in timing and type
of precipitation for locations such as Cordova and Kodiak Island.
Warmer southerly/southeasterly flow aloft with northerly surface
flow at the surface along the gulf coast may result in periods of
some mixed precipitation and freezing rain for areas on the
eastern Prince William Sound and Kenai Peninsula. Kodiak Island is
expected to begin as all snow before transitioning to rain Monday
morning. This shift towards a more active weather pattern keeps a
prolonged warm push of air into the area, trending temperatures
up through the early part of next week.

&&

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

An upper level low drops south out of the Interior towards
Southwest Alaska through this weekend. Cold air continues to
filter across Southwest, keeping temperatures sub-zero to single
digits. Blustery offshore flow will produce wind chills ranging
from -20s to -30s for most inland areas and 0 to -20 for coastal
areas. Additionally, gusty offshore winds will promote areas of
Heavy Freezing Spray along the ice edge and widespread freezing
spray across much of the eastern and central Bering Sea,
including waters surrounding the Pribilof Islands. As the low
moves offshore into the eastern Bering Sea, there is a chance for
some light snow, though no significant accumulation expected.
Winds will filter through Kamishak Gap, pulling some warmer air
into Bristol Bay by Monday, increasing temperatures into the 20s
(or low 30's for areas nearest to Kamishak Gap) from Iliamna to
the Western Capes and areas south.

An inverted trough at the surface pushes north across the Alaska
Peninsula and into the Bering Sea by Sunday afternoon. Areas along
the southern AKPen will be cold enough to see all snow while the
Eastern Aleutians may see a quick shot of rain/snow mix initially
before transitioning to all snow. Snow showers reach the Pribilof
Island early Sunday afternoon. Northeasterly small craft winds may
promote areas of blowing snow Sunday afternoon. There may be a
brief break in the wind and snow overnight Sunday into early
Monday morning as the trough axis moves over the Pribilof Islands.
On the backside, winds are expected to increase again to gale
force and snow will pick back up. There will be some warmer air
pulled in as well, increasing temperatures into the low to mid
30s, which will change the density of the snow to a heavy/wet
snow. Blowing snow may still be a concern for the Pribilof
Islands in which winds may produce areas of sideways falling snow
that could impact visibilities at times, however, there still
remains quite a bit of uncertainty due to a series of embedded
meso-lows developing within the trough at the surface. The trough
and associated meso-lows will eventually push towards the Central
Aleutians, somewhere between the Rat Islands and Atka, which may
result in areas of snow and/or blowing snow for the Central
Aleutians. There is lower confidence for blowing snow potential
and impacts along the Central Aleutians at this time.

&&

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

The main feature on the upper level Alaska Weather map is a well
developed closed low over the Central Aleutians. This low will
weaken as it drifts into the North Pacific by the end of the
forecast period. Combined with a ridge extending from Southeast
Alaska across the Interior provides an avenue for cold, dry air to
be pumped into the Bering. Forecast models are undergoing some
transitional uncertainty through midweek before reforming closely
by the end of the week. The ECMWF and UKMET hold most consistently
through the entire period. Widespread freezing spray over the
Central and Eastern Bering is expected. The connected surface low
extends an arc of snow changing to rain over the Southern Bering
and Central Aleutians through Wednesday.

A North Pacific low approaches the Eastern Aleutians, Alaska
Peninsula and Kodiak Island Tuesday. Locally heavy rains are
expected along the AKPEN, with snow inland and spotty areas of
freezing precipitation along the Bristol Bay coast North to the
Kuskokwim Delta and Etolin Strait. The rain spreads Eastward into
the Southcentral zones through Friday, with some small areas of
freezing precipitation continuing into Wednesday. Areas of snow
expected inland. A second North Pacific low approaches the Eastern
Aleutians and AKPEN on Thursday, spreading mostly rain to the
Central and Eastern Aleutians, across Bristol Bay East to the
Kenai Peninsula for early Friday.

&&

.AVIATION...

PANC...Patchy low stratus is currently noted on satellite this
morning over Knik Arm and north of Fire Island. There is
uncertainty on whether or not this makes it over the terminal. Any
low stratus or potential fog that does make it into the terminal
should lift by late morning when drier air moves in and the dew
point depression widens. Aside from the low stratus/fog potential,
VFR conditions and light winds will persist through the TAF
period.

&&