Gale Warning 68, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
538 AM AKST Fri Jan 12 2024

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

The amplified ridge that has been parked over Alaska and the Gulf
will begin to shift slightly off to the east today. The frontal
boundary that has been lifting towards and into the Gulf will begin
to mix out over the northern Gulf as the surface low moves north
into the AKPen. Models seem to be in good agreement with the
southern portion of this front developing a new low that will move
east into the PacNW. With cold airmass still firmly entrenched over
Canada and the eastern Gulf, the ridge will not make it very far
east before stalling again. However, the frontal boundary and
associated developing new low will help to dampen out the ridge
before it begins to amplify once again on Saturday. With the help of
another system lifting up into the Bering from the North Pacific,
the ridge will finally displace the Canadian low northwards as it
moves over western Canada by Sunday night.

The strong gradient that resulted in storm and gale force winds over
the Gulf, Barren Islands, and Kamishak Bay are gradually decreasing
this morning as the gradient relaxes over the northern Gulf. Gap
winds will also subside today. This first round of precipitation has
moved out of Kodiak with the western Kenai seeing light to moderate
rain and snow showers. Precipitation will also gradually taper off
over the Kenai and western Prince William Sound, but could see up to
a few inches of snow for the lower elevations, including Seward and
Whittier. As slightly warmer temperatures work into these lower
elevations today...may see enough of a bump to see a change-over to
some rain or a rain/snow mix at times. The western Kenai up through
the Mat-Su Valley should remain downsloped, but may see some
flurries pass through. However, measurable snowfall looks to hold
off until later this weekend.

Overall, the weather should remain pretty quiet for much of inland
Southcentral for today and into Saturday. Another low will dig south
of the Aleutian Chain through today before lifting towards southwest
Alaska tomorrow. The associated front will sweep eastwards through
the AKPen and western Gulf bringing another round of rain for Kodiak
Island and the eastern Kenai. There is a chance that precipitation
will work up Cook Inlet to the Anchorage Bowl and north into the
Valley by Sunday as flow becomes more southerly. The caveat will be
which model solution plays out as right now models are not in very
good agreement with either the position or the timing of the
associated trough and frontal boundary, nor the track of the surface
low. Right now, could see light light snowfall of up to a few inches
for lower elevations and a few more inches for hillside areas of
Anchorage and Eagle River; however, details will continue to be
refined as models come into better agreement.

- PP

&&

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

Active weather looks to continue throughout the short-term period
across the Bering Sea, Aleutian Chain, and Southwest Alaska.
Currently, a low pressure takes up residence in the south-central
Bering Sea. Its front has made it to the Pribilof Islands where
Saint Paul reports light snow. Meanwhile, mainland Southwest
Alaska sees precipitation begin to taper off as the frontal
system that brought all the active weather along the coast for the
last few days weakens and begins to fizzle out. However, the front
that is currently over the Pribilofs will push eastward through
today and make to coastal southwest later this morning providing
another round of light precipitation through much of the day.
Southerly flow will also strengthen through much of the day along
the coasts of Bristol Bay and Kuskokwim Bay. Water levels may rise
3 to 5 feet above normal highest tide for Kuskokwim Bay tonight
through Saturday morning with 2 feet above normal highest tide for
Bristol Bay. Bristol Bay could see an additional water level rise
of 2 to 4 feet Saturday evening through early Sunday morning with
a second round of strong southerly flow.

Attention quickly shifts to a North Pacific low lifting northward
to the Eastern Aleutians tonight and crossing into the Bering Sea
Saturday morning. Temperatures will initially be warm enough for
rain. However, strong cold air advection behind the low will turn
precipitation over to snow Saturday morning. The bigger story with
this system will indeed be the winds on the backside of the low
Friday night into Saturday for the Eastern Aleutians. A High Wind
Watch remains out for this evening through Saturday morning to
address the potential of winds gusting to 75 mph from Nikolski to
Unalaska and Akutan. Visibility could be reduced to as low as one
mile at times once snow begins Saturday morning.

Strong southeasterly winds from this system also look affect the
southern Alaska Peninsula (AKPEN) Friday evening for locations
like Cold Bay and False Pass. There will be a lull in the winds
Saturday morning before they pick up again Saturday afternoon with
a second round of gusty winds from the west. As this low moves
across the Aleutian Chain and into the Bering Saturday morning,
its front clips the Pribilofs late tonight into Saturday morning.
A Winter Weather Advisory has been issued to address reductions in
visibility to one-half mile at times due to snow falling in
conjunction with strong gusty northwest winds.

This low will continue to move northeastward and make it to
coastal Southwest by Saturday evening spreading precipitation
inland. This impactful looks to finally move northward of the area
Sunday towards the Bering Strait region. Cold air advection into
mainland Southwest from the Bering continues into Sunday with snow
showers continuing as well. Meanwhile, another low around
Kamchatka sends its front eastward over the Western Aleutians
Saturday and Sunday and eventually makes it to the Central
Aleutians Sunday evening. Accompanying this front will be a warm
push of southerly winds with cold air on the back side.

-DAN

&&

.LONG TERM FORECAST (Days 4 through 7: Monday through Thursday)...

An upper level ridge extends across the Bering through the
forecast period. A series of weak lows stream across from the
Russian Chukchi Coast and Arctic to develop a deepening trough
along the Alaska-Canada Border. A surface front riding over the
Bering portion of the ridge brings gusty winds with areas of gale
force gusts from the Western Aleutians into Western Alaska,
diminishing early Tuesday. Gusty Easterly winds remain South of
the Aleutians through Thursday. Moderate outflow winds develop
across Southcentral Alaska after midweek.

Kutz

&&

.AVIATION...

PANC...VFR conditions and light northerly winds will persist.

-TM

&&

SPECIAL WEATHER STATEMENT
National Weather Service ANCHORAGE AK
1107 AM AKST Fri Jan 12 2024

AKZ155-161-131400-
Kuskokwim Delta-Bristol Bay-
Including the cities of Bethel, Nunivak Island, King Salmon,
Dillingham, Naknek, and Pilot Point
1107 AM AKST Fri Jan 12 2024

...ELEVATED WATER LEVELS POSSIBLE THROUGH SATURDAY ALONG THE
NORTHERN KUSKOKWIM BAY COAST AND NORTHERN BRISTOL BAY COAST...

Periods of strong southerly winds combined with astronomically
high tides may cause water levels to rise above normal highest
tide. While higher than normal water levels are possible, it
seems unlikely that water levels would get high enough to cause
flooding in coastal communities. The most likely communities to
see higher than normal water levels include Kwigillingok and
Kongiganak (on Kuskokwim Bay) and Togiak (on Bristol Bay).

AKZ181-131400-
Alaska Peninsula-
Including the cities of Cold Bay and Sand Point
1107 AM AKST Fri Jan 12 2024

...STRONG WINDS COMBINED WITH FALLING SNOW ALONG THE ALASKA
PENINSULA ON SATURDAY...

A storm system over the Pacific will pass across the eastern
Aleutians tonight, bringing rain and southerly winds gusting
45 to 60 mph. As the low continues into the eastern Bering Sea
on Saturday, winds will shift to westerly and rain will change
to snow. The combination of westerly winds gusting 40 to 55 mph
combined with falling snow will reduce visibility to less than
one mile at times. The worst conditions will be along the Bering
Sea coast, including Cold Bay.