537
FXAK68 PAFC 111412
AFDAFC

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

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

A strong upper level ridge of high pressure is moving almost
directly overhead across Southcentral this morning, allowing for
continued tranquil and dry conditions for the entire region. A
band of upper level clouds wrapping around the periphery of the
ridge is starting to shift off towards the Copper Basin, while
much of the greater Cook Inlet and Mat-Su regions begin to clear
out. Patchy, shallow fog has popped up in a few spots thanks to
the still air and increasingly clear skies, allowing the surface
to radiate out and cool to the ambient dew point. Temperatures are
on the chilly side, with a number of surface observations across
the Kenai Peninsula, Mat-Su and Anchorage showing temperatures
dipping down into the mid 30s to low 40s.

For the rest of today, expect very similar conditions to
yesterday, with mild temperatures in the 60s returning at lower
elevations by the afternoon. Cloud cover will also begin to
increase with time ahead of a frontal boundary approaching the
Alaska Range from the northwest. By tonight, the front will cross
over into the northern portions of Southcentral, spreading rain
into the northern Susitna Valley and Talkeetna Mountains. Light
rain will spread south into the Chugach Range and Copper Basin by
Saturday morning, aided in part by multiple weak shortwaves
moving along the southbound front. It`s looking a bit more likely
for a period of light rain to reach the lower elevations of the
Mat Valley and Anchorage area (about a 50-70% chance) during the
morning hours on Saturday. Even so, expect rainfall amounts and
intensity to remain on the lighter side, with less than 0.1"
anticipated near sea level.

As the front continues to sag south and decay, steady rain will
taper off by Saturday afternoon and evening. Offshore gap winds
through Seward and Whittier will pick back up in the wake of the
frontal passage by Saturday night, but will stay weaker compared
to what we`ve observed over the past day or so. Sunday looks like
another day of benign conditions returning as zonal/westerly flow
prevails along with clearing skies once more. Much more active
weather could return early next week as a strong low pressure
system begins to take shape across the eastern Bering and
Southwest.

-AS

&&


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

Key Messages:

* A strong front moves across the Bering Sea and Aleutians through
  the end of the week, impacting Kuskokwim Delta starting today.
  It weakens as it moves across the rest of Southwest Alaska and
  the Alaska Peninsula into Saturday.

* Elevated water levels are expected along the Kuskokwim River and
  Kuskokwim Delta coast today. While flooding is unlikely, higher
  water levels may still impact activities along Kuskokwim River,
  Johnson River, and the Kuskokwim Delta coast.

* Otherwise, generally warm and humid, with areas of patchy fog
  under the influence of a ridge near the Alaska Peninsula and the
  influx of a warmer and moister air mass.

* For the weekend and beyond: A pair of lows lift across the
  Aleutian chain near Atka Saturday morning and Sunday afternoon,
  before reaching the Southwest mainland Sunday afternoon and
  Monday morning.


Discussion:

Currently, a nearly-linear front extends from the Kuskokwim
Delta, southwest across Adak/Atka, and into the North Pacific.
This front is accompanied by southerly small-craft advisory winds
and periods of moderate to heavy rain which will continue to
weaken from this morning through Saturday morning.

High water moving down the Kuskokwim River combined with storm
surge moving upriver will likely result in bankfull conditions for
communities along the Kuskokwim and Johnson Rivers, from
Kuskokwim Bay up to the Bethel area. Along the Kuskokwim Delta
coast, gusty onshore winds could also result in some coastal
erosion and minor coastal flooding from Kongiganak northward
through Toksook Bay and Tununak, but this looks increasingly
unlikely as sustained winds remain below 40 mph. A Hydrologic
Outlook remains in effect through this afternoon for these
concerns.

Bristol Bay and interior Southwest likely won`t see rain until at
least Friday afternoon. With fewer clouds and southerly winds
downsloping off the mountains, high temperatures will be around 60
for many locations around Bristol Bay down through the AKPen,
with some mid-60s possible around Pilot Point and Port Heiden.
Though the front continues to weaken as it progresses
southeastward, upper level support from shortwaves will allow
showers to persist through tonight for much of Southwest and the
AKPen, with activity slowly tapering off from west to east.

The front crosses the Alaska Range and moves into Southcentral by
Saturday morning, leaving a mostly zonal-flow regime in its wake.
Temperatures on Saturday 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 on Saturday. This
likely brings additional rain for the central and eastern
Aleutians beginning Saturday morning.

- PA/KC


&&


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

High pressure in the Gulf of Alaska will strengthen and move
eastward early next week in response to a deepening Bering Sea
trough. Through mid-week, the trough will allow for increasing
chances of rainfall and strong winds throughout the Aleutians, the
Alaska Peninsula and Southwest Alaska as the ridge over the Gulf
of Alaska moves across Southcentral. Ahead of the trough`s mid-
week passing, persistent southwest flow across the Aleutians and
into Southwest Alaska will result in continued onshore wind and
rain these areas. Additionally in the wake of the trough`s
passing, weak waves of low pressure will bring reinforcing periods
of increased winds and rain through week`s end despite a general
zonal flow returning to the area.

A drier period for early next week is expected in most of
Southcentral. Rain coverage and strong winds will begin to
increase first in Kodiak and Kenai Peninsula and also in the far
western areas of Southcentral across the Alaska Range. Towards
mid-week, rain and wind begin to cover more of Southcentral
reaching Prince William Sound and the Copper River Basin by the
end of next week.

-Johnston


 &&


.AVIATION...

PANC...While VFR conditions are mostly anticipated through the
TAF period, there is a chance (10 to 30%) that fog could develop
around the terminal this morning. If fog does develop near or
over the terminal, conditions will improve through mid-morning as
the sun comes up and the fog begins to burn off with day-time
heating.

&&

$$