286
FXAK68 PAFC 271352
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
552 AM AKDT Fri Jun 27 2025

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

Little has changed from this afternoon with satellite imagery
reveals a quasi-stationary, occluded, complex low pressure system
roughly situated south of Kodiak Island with mid level clouds
streaming northward into Cook Inlet, the Kenai Peninsula, and
farther inland. Coastal ridging along the Gulf coast continues
though it has weakened a bit, allowing for winds through Turnagain
Arm wind (to a lesser extent, the Knik Arm and Copper River Basin
gap winds) to come down. Aloft, there is a broad upper low
circulation tied to the aforementioned surface low with several
embedded troughs rotating around its periphery. This has allowed
for showers to continue along the Gulf coast and Kodiak Island
with a stray shower making it over to the Cook Inlet communities.

Farther south, the low`s front continues to trend slowly
northward and timing of precipitation in the short term forecast
has been the primarily forecast challenge. The front is not
expected to the Gulf coast until late tonight or early Saturday.
With certainty though, rain will likely remain for Kodiak Island
through at least Saturday morning and then gradually decrease
through the weekend. Showery conditions and small craft conditions
are also forecast primarily through the Shelikof Strait. Across
the Gulf, winds will be around 20 kts along the front. A wave of
precipitation may develop ahead of the front as it lifts toward
the northern Gulf. A few showers and isolated thunderstorms may
develop along the foothills of higher elevations, including the
Alaska Range and the eastern slopes of the Talkeetna mountains
during the afternoon for today and Saturday.

The potential for precipitation chances across Southcentral
increases for this weekend as an easterly shortwave moves across
the Copper River Basin. Models continue to struggles with timing
and overall strength of the shortwave, making confidence of
details of the forecast lower than average. However, based on
current model guidance, there could be a few lightning strikes
associated with storms that may develop Saturday afternoon as
colder air moves in aloft with the wave, steepening lapse rates as
it does so. Not only does this provide instability, but it also
can increase rainfall rates within showers. Precipitation chances
then appear to spread into the Matanuska and Susitna Valley
Saturday afternoon and may stretch southwestward into Anchorage
and the western Kenai Peninsula as a combination of the
deformation band and added energy of the wave phases. Another
added possibility is that dynamics could align well enough to
develop a mesolow and work its way southwestward. Again, models
still are not in agreement on the timeframe as some models are
holding off until Sunday morning for any precipitation, and there
is still a question of how much rainfall the area could see. If
some of the short to mid range guidance today is correct, much of
Southcentral could see a soaking rain to start the work week,
especially in places with orographic enhancement. Details will
become more clear over the next few days.

-McCormick/Rux

&&


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

The large low south of Kodiak Island continues to slowly drift
eastward into the Gulf this morning while a surface trough
associated with the system moves across the eastern Aleutians and
Alaska Peninsula into the North Pacific through this morning.
Light rain showers continue across much of Southwest Alaska as
precipitation spills over the Alaska Range within the easterly
flow associated with the aforementioned low. Light northerly flow
and widespread low stratus with areas of fog and lower
visibilities blankets the southern Bering and Aleutian Chain as a
ridge of high pressure continues to build in the western Bering.

The upper level shortwave currently over the western Interior
continues to track westward towards Norton Sound before stalling
near the coast on Saturday. Beyond this point, some uncertainty
remains on the track of the system though it looks likely the
system dips towards the south allowing for a period of light rain
to develop across the Kuskokwim Valley and northern portions of
the Kuskokwim Delta Saturday morning into Saturday afternoon.
Meanwhile, increasing temperatures and breaks in the clouds with
remnant moisture from the easterly waves will allow for the
development of scattered rain showers and isolated thunderstorms
Saturday afternoon and evening across the Western Alaska Range
and portions of Bristol Bay potentially extending as far south as
Dillingham and King Salmon. Further west, the potential for fog
continues underneath the ridge for the Aleutians and Southern
Bering through Saturday. By Sunday morning, a Kamchatka low begins
to flatten the ridge and moves into the western Bering bringing
gusty southerly winds and rain to the Aleutians.


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

A broad, closed upper level low over the Gulf of Alaska maintains
its overall sojourn around the Gulf of Alaska and Eastern North
Pacific. Some additional support from a shortwave rotates around
the center with little change in strength through the forecast
period. A upper level Bering ridge eases over Western Alaska by
Thursday. Gaining some strength from the remnants of Tropical
Depression Sepat, an elongated trough over the Bering becomes a
closed upper low through the week. The overall guidance comes from
the GFS through the entire period, where the differences extend
with the rest of the models through the week mostly in the Western
portions of the region. An increased use of model ensemble
guidance is required after Tuesday.

The week opens up with a fairly strong Northwest Bering surface
low. Its front extends over the Bering and Western Alaska to the
Aleutians with locally moderate rain and breezy conditions, before
the Aleutian portion slides into the North Pacific late Monday.
The front continues moving into the Alaska Peninsula and Southwest
Alaska for Tuesday, diminishing Tuesday night as the surface low
moves across the AKPEN. Locally moderate rain and isolated
thunderstorms subside over the Eastern Interior Alaska nearer the
Canadian border through Monday. Scattered showers remain across
most of the Southern Interior through Thursday.

- Kutz

&&


.AVIATION...

PANC...VFR conditions prevail through the TAF period. Turnagain
Arm winds have subsided this morning but return this afternoon
with sustained winds of 10 knots and gusts up to 15 knots possible
between 00Z and 09Z.


&&


$$