383
FXAK68 PAFC 120217
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
617 PM AKDT Fri Sep 11 2026

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

A strong ridge of high pressure passes over Southcentral today,
bringing another mild and dry day across the region. While skies
have cleared for most, some patchy fog/low stratus persists along
parts of the western Kenai Peninsula and eastern Kodiak
Island. More widespread cloud cover will gradually fill in
tonight as this ridge tilts eastward, exposing the area to
southwesterly flow. Chances for precipitation return tomorrow
morning as a weak shortwave trough pushes across the interior,
with light rain expected to spread into the Anchorage Bowl, Mat-
Su Valley, and eventually into the Copper River Basin. Dry air
filters in rapidly behind this system, allowing precipitation to
taper off by the late afternoon for most areas.

In the wake of the frontal passage, offshore winds through Seward
and Whittier will pick up tomorrow night, gusting 30 to 35 mph
through Sunday morning. Quiet weather returns for Sunday as
zonal/westerly flow prevails, bringing seasonal temperatures and
mostly sunny skies. These benign conditions will continue Monday
morning, but cloud cover will once again build from southwest to
northeast through the afternoon as a strong frontal system
approaches the Gulf. There are model discrepancies regarding the
onset of precipitation, with a 25% chance by Monday evening,
across Southcentral. Expect a much more active pattern moving
into mid-week with widespread wet and windy conditions.

-CW

&&


.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (Days
1 through 3: This afternoon through Monday afternoon)...

Key Messages:

* Generally improving conditions as the front weakens and exits
  the area. Increasing chance of fog this evening through tomorrow
  morning.

* A strengthening low that moves from the Aleutians early Sunday
  morning and clips the YK Delta on Monday could bring onshore
  winds and perhaps a round of elevated coastal water levels. We
  continue to closely monitor this storm.

Discussion:

The front crosses the Alaska Range and moves into Southcentral by
tomorrow morning, leaving a mostly zonal-flow regime in its wake.
Temperatures tomorrow look to be mostly near average. Some
isolated showers will linger through the day, with more scattered
showers along the Alaska Range down through the AKPen due to
upsloping winds. Any upper level support with shortwaves will also
maintain lingering showers, though precise timing of shortwaves
is currently unclear. To the west, a weak system looks to move
from the North Pacific to the Central Aleutians later tomorrow.

This low has been an area of major forecast uncertainty these past
few days. The impetus for this feature will be an array of robust
upper level shortwaves riding along the ridge and northeastwards
into the Bering Sea and Southwest Alaska; models had previously
struggled mightily with how these various shortwaves would
interact and phase with each other. Forecast confidence seems to
be improving as the models coalesce on a singular low (previously
there had been 2) that will likely bring a period of onshore winds
to Kuskokwim Delta. It`s hard to say for now what coastal impacts
there may be; models continue to show poor run-to-run consistency
regarding the track of the low and, therefore, the strength and
duration of onshore winds. We`ll continue to monitor this storm.

-KC

&&


.LONG TERM FORECAST (Days 4 through 7)...

Forecast models are coming into general agreement with the
synoptic pattern early next week with a developing trough over the
eastern Bering and a deepening surface low and front approaching
the YK Delta on Monday. As the low continues to deepen into into
Tuesday just southwest of the Seward Peninsula, its broad front
pushes across all of Southwest Alaska and the Alaska Peninsula
through Tuesday night. The same front moves into Southcentral by
the middle of next week, aided or reinforced by a shortwave trough
traveling along the front from the Gulf of Alaska, with the front
pushing into western Canada by Thursday evening.

While finer details remain unresolved, including small
differences in timing, the exact track of the low, as well as the
strength of the low and potential phasing with other shortwave
features, increased confidence exists that much if not all of
Southwest experience a period of rainfall and gusty winds Monday
into Tuesday, with the same these same hazards to impact
Southcentral on Wednesday.

Weak high pressure attempts to build into Alaska Thursday into
the end of the week. Residual areas of rain activity will likely
linger across parts of both Southwest and Southcentral on
Thursday, decreasing further by Friday. The only interesting
feature to note in the long term forecast is the arrival of yet
another North Pacific low lifting into the Western Aleutians at
the end of the forecast period.

-BL

&&


.AVIATION...

PANC...VFR conditions and light winds will persist through most of
the night. Toward morning, an approaching front will bring some
light rain to the area which could usher in a brief MVFR ceiling
Saturday morning. Winds are expected to shift southeastward late
tonight through Saturday morning but should not get higher than
about 8 to 12 kts.

&&


$$