389
FXAK68 PAFC 180207
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
507 PM AKST Mon Nov 17 2025

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

A negatively-tilted upper trough that moved quickly past much of
Southcentral this morning has shifted steadily east since this
morning, now extending from near Cordova up into the Copper
Basin. Steady snow and rain near the coast has also given way to
widespread bands of showers behind the trough passage as cool air
moving in aloft supports very steep deep layer lapse rates and an
overall unstable atmospheric profile. These clusters of showers
are riding up through disorganized southwesterly flow setting up
across the region. A particularly vigorous area of rain and snow
showers is now moving up into the Kenai Peninsula and Cook Inlet
along and ahead of a weak shortwave impulse driving northeast from
the western Gulf. This could bring another quick round of snow to
parts of Anchorage and the Mat-Su Valleys as it continues north
later this evening into tonight. While briefly heavy snowfall
rates will be possible with the convective nature of these
showers, most of the western Kenai Peninsula up through the Mat-Su
is not expected to see more than an inch or so of new
accumulation overnight. Bands of showers in the form of rain along
the immediate coast and mountain snow will also continue to
stream into Prince William Sound and much of the Chugach Range
this evening into tonight.

Forecast details from Tuesday onward remain rather murky. Overall,
the pattern for Tuesday will be fairly similar to today, with
continued southwest flow and areas of rain and snow showers moving
past at times, especially along the Gulf Coast. From Tuesday night
into Wednesday, an inverted trough extending from a low entering
the far eastern Gulf will begin to bend northwest into the
vicinity of Middleton Island. A swath of moisture coupled with
weak lift north of the surface trough could make it into eastern
fringes of the outlook area near Valdez and Cordova by Wednesday
afternoon, but this remains highly uncertain given the model
spread for where this feature sets up and for the track of the low
moving up into the eastern Gulf.

Forecast confidence deteriorates even further by Wednesday night
into Thursday. A complex trough moving south of the Aleutians is
expected to bend northeast towards the Alaska Peninsula between
Wednesday and Thursday, likely inducing the development of a
strong surface low somewhere between Bristol Bay and the western
Gulf. This discrepancy in where the low forms has significant
implications regarding any potential for strong winds and
precipitation type/amounts near and to the east of this system
across Southcentral. The signal through the noise is that much of
the Gulf could experience gale force winds, possibly stronger,
from Wednesday night into Thursday, with potential for heavy rain
and snow for coastal parts of Southcentral along and ahead of the
low`s front. The air mass moving in with this system also looks
fairly mild, and this could cause some issues with mixed
precipitation types for anything that makes it over the coastal
mountains into the Mat Valley, Anchorage and Cook Inlet region.
However, this will hinge on details for the progression of this
low that are still far from fully resolved. Stay tuned for updates
as we follow this next upcoming storm system and as confidence
for the track and intensity of this feature improves.

-AS

&&


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

The low that continues to bring a mix of rain and snow showers to
the Kuskokwim Delta and Nunivak Island this afternoon has drifted
to the north of Nunivak Island, and continues advancing northward
to near St. Lawrence Island by Tuesday morning. Southerly winds
gusting between 30 to 40 mph through this evening will begin to
weaken through Tuesday morning as they shift more southwesterly.
Colder air wrapping in behind the departing low will allow for
showers across the Kuskokwim Delta and Kuskokwim Delta Coast to
transition back to snow and for any rain across Bristol Bay to mix
with snow at times tonight into Tuesday. The majority of moisture
moving into Southwest off the Bering Sea, in the wake of the
strong low, will impact mostly the Kuskokwim Delta and Kuskokwim
Delta Coast Tuesday where a couple inches of snowfall will be
possible.

The next notable storm system moves into the western Bering
Tuesday morning as a front brings gusty southeast winds to the
Western Aleutians Tuesday morning along with moderate rain. The
front moves eastward across the Bering and Aleutians through
Wednesday morning as it makes it to the Pribilof Islands by then.
The frontal system eventually tracks into the eastern Bering and
reaches the mainland Southwest coast by mid-Wednesday morning.
Gusty southerly winds up to 35 mph will accompany the front at the
coast. There remains some uncertainty on exactly where a compact
low pressure might spin up along the front, though a track between
Nunivak Island and St Matthew Islands looks like the most likely
scenario. The bulk of precipitation associated with this system is
again expected to mainly impact the Kuskokwim Delta Tuesday night
through Wednesday morning. Warm, southerly flow will allow for
snow to transition to a rain/snow mix along the Kuskokwim Delta
Coast by early Wednesday morning, while any precipitation that
makes it into inland Kuskokwim Delta likely remains light snow.

Yet another point of uncertainty will be the potential for a
stronger low to move into the southeastern Bering by Wednesday
night into Thursday. A northern solution would bring more in the
way of heavier precipitation across mainland Southwest Wednesday
night into Thursday while a southern solution, more into the North
Pacific, would keep the gusty winds and heavy precipitation
confined to the Eastern Aleutians and Alaska Peninsula. Stay tuned
to forecast updates as the active pattern looks to continue.

&&


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

Forecast confidence is generally low from late this week through
early next week. Generally expect stormy weather as a low impacts
Southern Alaska on Friday, followed by a brief break before the
next storm moves into the Bering Sea from the west.

Broad upper level troughing will be present over the Bering Sea
by the start of the long term forecast period. A robust shortwave
curving up from the North Pacific will spur the development of a
surface low near the Alaska Peninsula. However, model solutions
remain very divergent, which makes forecast details and potential
impacts difficult to pinpoint. Among the deterministic solutions,
low tracks range from the low curving up the Southwest Alaska
coastline, to the low moving onshore in Bristol Bay, to the low
curving up the Gulf coast towards Prince William Sound. Given the
strength of this low (minimum MSLP as low as 950-960 mb), gales
are likely, with sustained storm force winds possible. All told,
this will be a potentially impactful storm, and one to watch as
forecast confidence gradually improves.

As the aforementioned low gradually weakens and exits out of the
Southern Mainland, a ridge will move in, followed by the front
from a strong low that moves in by Saturday. Winds to storm force
are possible with this front, impacting the Western and Central
Bering/Aleutians. As the front approaches the Mainland by Monday,
secondary lows developing along the front will lead to stormy
weather along the Bering Sea, though uncertainty with low tracks
will once again lead to difficulty pinpointing exact details.
Overall, a low-confidence long-term forecast.

&&

.AVIATION...

PANC...Radar continues to show snow showers moving northward from
the Kenai Peninsula toward the Mat-Su Valley this afternoon. As
this flow continues overnight, light snow showers are possible
through the Anchorage Bowl with some becoming 12Z to 15Z tomorrow.
Scattered snow showers will likely develop after 18Z. &&


$$