Gale Warning 104, NWS Anchorage, AK

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
452 AM AKST Sat Jan 29 2022

.ANALYSIS AND UPPER LEVELS...

This morning on satellite imagery, the remnants of an occluded
front span over the Gulf Of Alaska, another occlusion over the
Western Aleutians and a Pacific low south of Adak. There is an
area of high pressure from the Bering Strait to Bristol Bay. The
radar at Middleton Island has been active early this morning. One
finger of the jet is south of Adak with a magnitude of 100 knots.
There is a second jet core over the northwest Pacific with a
magnitude of 165 knots. On ASCAT (Advanced Scatterometer) an area
of gale force winds was detected south and north of Shemya
associated with a 975 mb surface low.

&&

.MODEL DISCUSSION...

By Sunday morning (12z), the models are showing some divergence in
solutions. There are some differences with the track and
intensity of the low exiting the Gulf and the next North Pacific
low. Differences emerge with precipitation shields for the
respective lows. These model discrepancies become more pronounced
at 48 hrs and 36 hrs.

&&

.AVIATION...

PANC...VFR conditions are likely to persist. Light northerly
winds will diminish this evening. Dry weather expected at PANC
through Monday.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...

Satellite shows two distinct low centers over the Gulf of Alaska
region early this morning. The first is associated with the upper
level low that is now situated east of Kodiak Island. This is the
source of the light snow and gusty winds in the Kodiak area. These
winds should diminish and snow end today as this low continues to
track eastward. The second low is a surface low which is over
Middleton Island early this morning and moving westward. The
moisture associated with this low is bringing in more clouds from
the east to much of Southcentral this morning. As this low
weakens and turns southward, the cloud cover will being to lessen
over Southcentral from north-to-south. While there are good
returns on the Middleton Island around this low, Cordova is the
main area that is seeing precipitation (in the form of rain). It
does not look like this precipitation will make it very far
inland even for other areas along the north Gulf coast and it may
not even be able to get to Whittier or Seward.

The gusty northeast winds in the Matanuska Valley will persist
through most of the day and then taper off this evening.

After today, there should be clearing over the area until the next
system moves into the area from the Southwest. This system should
reach the Kodiak area Monday and then the rest of Southcentral by
Tuesday.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 3:
Today through Monday)...

A low pressure system over the Gulf that brought light snow to
parts of Bristol Bay overnight will continue to move east with
clouds clearing by later today. High Pressure will then build in
from the Bering through the weekend with clear and cold
temperatures. Winds will also weaken across the area as we head
into Saturday and Sunday. By Monday temperatures will begin to
warm ahead of a warm front moving across the eastern Bering. This
will bring a chance of precipitation by Monday afternoon and
evening near coastal areas which could be in the form of freezing
rain as warm air over- rides colder air at the surface. There is
still some uncertainty on the precipitation type and timing of
precipitation, so stay tuned.

&&

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

Gusty northwest winds south of the AKPen will gradually wind down
through Sunday morning as the cold air advection ends.

A low pressure system near the western Aleutians will move
northwest towards Kamchatka over the next 24 hours, this low will
produce mainly high end gales but small pockets of storm force
winds are possible today. Farther east high pressure will continue
to dominate from near St Matthew Island and south towards the
eastern Aleutians with quiet weather. On Sunday another low
pressure system replaces the high pressure and brings gale force
winds with some storm force winds possible near the low as it
crosses the central Aleutians Sunday afternoon. This low will move
northwest across the Bering through Monday. While its front
pushes across the Bering Sunday and Monday as it moves towards
Southwest Alaska.

&&

.MARINE (Days 3 through 5 - Monday through Wednesday)...

Gulf of Alaska:

High pressure exits the Gulf for Tuesday. A front enters the
Western Gulf Tuesday and extends across the Gulf by Wednesday.
Forecast confidence is good. Southerly gales are likely as the
front cross the Gulf, particularly in the barrier jet locations
along the north Gulf coast as well as in the Barren islands to
Kamishak Bay area. These stronger winds look like they will be
brief, diminishing by Wednesday.

Bering Sea/Aleutians:

Expect an active weather pattern across the Bering Sea and Aleutians,
with multiple storms tracking from the Pacific northward across
the Bering Sea. Forecast confidence in the specific track of each
storm is low. However, confidence is high in a long duration of
gale force winds across the region. There is also potential for
smaller areas of storm force winds near the low centers. Seas will
remain elevated above 20 feet for the much of the three day period.

&&

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

A robust blocking pattern dominating the Gulf will remain in place
in spite of multiple long-wave troughs from the Bering riding
along the high trekking through the Southwest and Southcentral
through the long term. These waves could bring increased clouds
and potentially light snow and a wetter regime over the area. As
the ridge axis settles across the state beginning Wed morning,
dry conditions and rising temperatures are expected for both
Southwest and Southcentral. Though precipitation type issues may
become a challenge, the presence of the upper ridging could help
minimize unstable energy lurking farther inland of Southcentral by
Fri and Fri night.

Over the Bering/Aleutians, a gyre complex North Pacific low will
usher stronger winds with periods of higher gusts along the gaps
and passes starting Tue afternoon through Wed night. Another North
Pacific low races through the central Aleutians bringing more
tropical moisture and stronger winds there and Pribilof Islands
into Fri afternoon. Warm temperatures associated with the
aforementioned lows will produce rain/snow mixed over much of the
Bering/Aleutians through the end of the week. Model solutions
struggled quite a bit with the wind coverage of the latter low,
but clearly points out similar tracks as the low pushes north of
the southern Bering Fri morning.

&&
.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Storm 411 174. Gale 412 413 414 150 170 171 172 173 175
176 178 179 185 352 130 131 132. Heavy Freezing Spray 414 412 150
165 179 185 130 138.

&&

SYNOPSIS AND MODEL DISCUSSION...PJS
SOUTHCENTRAL ALASKA...EZ
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...RLC
MARINE/LONG TERM...CB