907
FXAK68 PAFC 040055
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
455 PM AKDT Thu Apr 3 2025

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

High pressure extending west from Canada has afforded mostly
sunny skies that have allowed temperatures to warm into the 50s
across most of Southcentral Alaska, with some locations
approaching 60 degrees this afternoon. The pleasant weather will
deteriorate somewhat as a large low pressure system swirling in
the North Pacific lifts its occluded front to the Southcentral
coast tonight. The front will start to bring rain and some high
elevation snow to Kodiak Island as early as this evening before
spreading north into the Kenai Peninsula overnight as it stalls
out there through the weekend. The vast majority of impacts from
this storm will be along the coast, with easterly winds to gale
force over the northern Gulf of Alaska and moderate to heavy
rainfall. Snow levels will remain fairly high, starting out at
around 1000 to 1500 feet early Friday morning, then rising 1800 to
2500 feet by late Friday. Thus, snow should not be a big issue
along the road system.

Inland areas will remain mostly dry with strong downsloping flow,
though there could be an occasional brief period of light
precipitation as weak upper short-waves track inland. The first
chance for this appears to be tonight with the initial arrival of
the front bringing potential for light precipitation sweeping
north across interior areas through Friday morning. Similarly
expecting another shortwave to lift across the region Friday
night, with greater potential for some rain or snow, with
temperatures forecast to drop into the low to mid 30s, in the
Copper Basin. Otherwise, temperatures will remain above normal,
with a trend toward above freezing night-time temperatures due to
extensive cloud cover. By Sunday, an upper- level low elongates
across Western Alaska leading to weaker cross-barrier flow over
Southcentral and enhanced potential to draw moisture into inland
areas resulting in increased chances for precipitation.

&&


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

...Key Messages...

 1) A Winter Storm Warning is in effect from 7AM Thursday to 4PM
    AKDT Friday for the Eastern Aleutians.

 2) A Blizzard Warning is in effect from 10PM Thursday to 7PM
    AKDT Friday for the Kuskokwim Delta Coast and Nunivak Island.

 3) A Special Weather Statement has been issued for the Pribilof
 Islands from 1AM Friday to 7PM Friday for snowfall and strong
winds.

Currently, an upper level low over the Central Bering is aligning
well with a secondary upper low steadily approaching the region
from the North Pacific. This has formed an intense deformation
band of rain and snow for areas such as Nikolski and Unalaska.
Some of this moisture is spreading northward as the precipitation
on its northwestern flank pivots more so to the north and west
ahead of the low`s front paralleling the Aleutian Chain. In
combination with cold air advection on the backside of the surface
low, widespread gales and storm force wind gusts are impacting
the Eastern Aleutians, which is resulting in significant gap wind
gusts of 45-55+ kts through mountainous areas near Unalaska and
Akutan. Conditions should deteriorate following an expected peak
Friday morning. Accumulations of 10-18" of snow with winds
gusting upwards of 60 mph is likely for these areas by midday
Friday to Friday afternoon, with localized areas of 20"+ not out
of the realm of possibility. On the other hand, a robust southerly
to southeasterly flow will keep temperatures elevated into the
upper 30s to lower 40s for Sand Point eastbound, making this
primarily a rain event for the AK Pen and Southwest.

Snowfall also begins to spread northward by late Thursday to early
Friday, and conditions quickly start to go downhill for Nunivak
Island and the Kuskokwim Delta coast, including areas such as
Kipnuk, Mekoryuk, and Toksook Bay. As snow begins to fill in and
winds increase into Friday morning, blizzard conditions are likely
for these areas, especially Nunivak Island. Given the proximity to
surrounding sea ice, Mekoryuk has the best chance of seeing
blizzard and whiteout conditions from this storm, but these
conditions are still expected to be felt inland along the
Kuskokwim coast. These conditions will persist throughout the day
on Friday and finally slowly begin to wind down on Saturday
morning, perhaps lingering into Sunday. Areas within the Blizzard
Warning are expected to see 5-9"+ of snow with winds gusting
upwards of 40 mph.

For the Pribilof Islands, blowing snow due to strong winds could
reduce visibility down to a half mile at times from Friday
morning into late Friday afternoon. There is still some
uncertainty with the models on just how far the edge of the
aforementioned band of snow pushes westward, so snowfall totals
are more in question than blowing snow potential due to a strong
30-40kt fetch of northerly winds forecast to affect the Islands.
Even with lesser amounts of snow than other areas, light snowfall
accumulations with strong winds can still create blowing snow
conditions. Model consensus continues to suggest 1-3" of snowfall
for the Pribilof Islands by Saturday morning. As such a Special
Weather Statement has been issued for the Pribilofs from Friday
morning through Friday evening.

-AM/CL

&&


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

The most significant feature on the Alaska Weather map is an
elongated trough stretching from the Arctic through Interior
Alaska to the Gulf of Alaska through the forecast period. Closed
lows over Northern Alaska and the Gulf weaken through midweek.
Although there is some oscillation within the elongated trough,
there is little movement. Ridges over the Western Canadian
Provinces and the Bering also weaken through the period. Forecast
continuity remains good with a GFS / ECMWF / Canadian blend, but
minor differences with shortwaves gliding through the pattern
represent the variations and short term changes in forecast.

A moderately strong surface low over the Southern Gulf of Alaska
spreads locally heavy rainfall from the Eastern Aleutians over the
Alaska Peninsula through Monday. Gusty winds over the AKPEN
linger through midweek. Locally heavy rains marches across Kodiak
Island and the rest of Southcentral Coastal zones through
Wednesday. Areas of locally moderate snow spread over Southwest
Alaska into the Interior, and diminish through midweek. A well
developed low and front approaches the Western Aleutians for
Sunday, but dissipates to the South of the chain by Tuesday.

- Kutz

&&.AVIATION...

PANC...Southeasterly Turnagain Arm winds gusting to around 25 kt
(30 mph) will continue through this evening. After that, VFR
conditions and light winds will persist through tomorrow morning.


&&




$$