013
FXAK68 PAFC 060325 RRA
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion...DELAYED
National Weather Service Anchorage AK
725 PM AKDT Thu Jun 5 2025

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

A broad upper-level trough is situated over Southcentral Alaska
this afternoon. The trough has weakened through the day, allowing
for increasing breaks of sun to produce some marginal instability
to support shower activity across the Copper River Basin and the
west facing slopes of mountains from the Talkeetnas south to the
Kenai Mountains. An isolated thunderstorm is possible for the
Susitna Valley, northern Kenai Peninsula, and much of the Copper
River Basin as the sun continues to heat the surface through the
evening hours. Tonight, shower activity diminishes as the bulk of
the upper-level energy exits into Canada.

Friday will be the nicest day of the week for most areas as some
ridging moves overhead. While it will be sunny for most locations
through midday, high level cloud will begin to overspread
Southcentral in the afternoon ahead of the next system for this
weekend. A low lifting into the Gulf of Alaska will help to build
a coastal ridge, inducing southerly flow and generating another
round of pesky gap winds through Turnagain Arm and the Knik and
Copper River Valleys. The Copper River wind will likely inhibit
shower development over much of the Copper River Basin, but
locations north and east of the Wrangells and also in the northern
basin (near Paxson and along the Denali Highway) have potential
for isolated thunderstorm development on Friday afternoon/evening.
Later in the evening, the leading front reaches Kodiak Island and
eventually the Gulf coast early Saturday morning.

The front brings strong winds along the north Gulf coast, reaching
storm force near Kayak Island. The low pressure breaks down the
coastal ridge, and gap winds will generally diminish for
Saturday. This will allow widespread rain will once again blanket
the region through the day as the Gulf low interacts with another
polar trough digging across western Alaska. Similar to yesterday,
expect wet conditions and well below normal temperatures for
Saturday. In Anchorage, temperatures may struggle to reach 50
degrees yet again. Conditions begin to improve on Sunday with
potential for breaks of sun, though most areas will remain
showery. There is potential for a weakening front to remain in
place over the Kenai Peninsula, Anchorage, and the Mat- Su Valleys
on Sunday. Meanwhile, the Copper Basin looks drier.

&&


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

This afternoon`s isolated rain showers will diminish across the
SW Mainland overnight. In their wake, partly clear skies are
expected. Another North Pacific low moving toward Kodiak Island
will bring increased cloud cover tomorrow evening into Saturday to
the Bristol Bay coastline. Also, scattered rain showers and wind
gusts ranging from 20 to 30 mph can be expected along the
coastline. Unseasonably cool air will work its way into the
northern portions of the SW Mainland; from Goodnews Bay to
Sleetmute Saturday morning as cooler air moves southward. With a
persistent north to northwest wind, surface temperatures will
struggle to climb out of the 50s. The northwest winds will also
result in scattered rain/snow showers in the Alaska Peninsula and
Aleutians on Saturday.

A ridge continues to build into the Western and Central Aleutians
through a quick moving low slows this ridge`s eastward
progression. This low dips down from the Interior through the day
Saturday aiding the cold air`s migration southward and the ridge`s
eastward progression for the first part of the weekend. Fog forms
under this ridge in the Aleutians.



&&

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

A closed upper level low over Southwest Alaska takes a slow track
across the Gulf of Alaska to near Queen Victoria Island through
the forecast period. A weak upper ridge follows from the Eastern
Bering across Interior Alaska. A broad trough forms over the
Bering through Thursday. Using an ensemble of GFS / ECMWF / UKMET
and Canadian models carries a good level of certainty and
continuity. the weather pattern is setting up for a series of
transient storm systems.

On the surface, widespread rain with mountaintop snow extends
across most of the Southern Mainland through Tuesday, as a
decaying low moves across the Gulf of Alaska. In the West, a well
developed low and front spreads moderate to locally heavy rain
beginning in the Western Aleutians and Bering for Monday, and
pushing over the Northern Bering and Eastward into Southwest
Alaska and the Alaska Peninsula for Tuesday. Gusty winds are
expected over the Western and Central Aleutians Tuesday,
diminishing late. This system continues over Kodiak Island
Wednesday, slowly diminishing in areal coverage by Thursday. A
weak low trails behind with more rain over the Western Aleutians
through Thursday.

- Kutz

&&


.AVIATION...

PANC...VFR cigs and vis will prevail through Friday morning along
with light southerly winds. Vicinity showers are possible through
this afternoon and evening, with any shower activity likely east
of the terminal and along the foothills of the Chugach range
given the southwesterly flow near the surface and westerly flow
aloft. If any showers do develop closer to the terminal, ceilings
may lower briefly to around 3,000 ft. While sustained winds are
expected to remain around 10 kt or less, an isolated gust up to 20
kts is not out of the question through late this evening.

&&


$$