616
FXAK68 PAFC 301327
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
527 AM AKDT Sat Aug 30 2025

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

Key Messages:

 - Flood Advisories remain in effect across Mat-Su and in the
   Cordova area, and many rivers still have elevated river
   levels.

 - Mostly clear skies overnight led to lows dipping into the 30s and
lower 40s this morning, with a few areas of patchy fog developing.

 - Labor Day Weekend: Generally warm, partly to mostly cloudy. Dry
through Saturday afternoon, with a chance of light rain thereafter.
Localized breezy areas in the afternoon and evening.

Discussion:

Quieter weather this Labor Day weekend across Southcentral as
high pressure builds over the Gulf. The recent rainfall combined
with light winds will allow for some areas of patchy fog this
morning. Some midlevel cloudcover is starting to work into SW
quadrant of Southcentral as another trough over the Bering lifts a
front through the Aleutians and southern AKPen. Cloud cover will
continue to increase as the front lifts north today and could see
some light showers move across the northern Susitna Valley later
tonight. Overall amounts look to remain light with better chances
for accumulation over the Bristol Bay area where better forcing
will be in place. Another shortwave will take a similar track
Sunday...clipping western Susitna Valley. The primary trough will
lift through early next work week bringing another round of
showers through the western half of Southcentral.

While this past weeks heavy rainfall has ended...several rivers
across the Mat-Su and Cordova areas continue to remain in flood
stage this morning, and many rivers will remain elevated
throughout the weekend.

- PP

&&

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

A deep occluded low continues to take up residency over the
western Bering this morning. On satellite, its front stretches to
Nunivak Island and then southwestward through the Eastern
Aleutians. CIMSS MIMIC Layer precipitable water shows 1.0 to 1.5
inches of precipitable water over the eastern Bering along the
front, and higher amounts approaching 2 inches south of Nikolski.
This atmospheric river will bring more rain to Southwest Alaska
and the Aleutians through the weekend into early next week, as the
front makes slow eastward progress into the Alaska Peninsula the
next 24 to 48 hours. As has been touched upon in the previous
forecast discussion, widespread rainfall is anticipated today and
tomorrow for the Eastern Aleutians and Southwest Alaska. Forecast
rainfall totals remain largely unchanged.

Areas along the coast can expect to see heavier precipitation as
well as higher amounts compared to inland areas. Southern portions
of the southern Alaska Peninsula, primarily King Cove and False
Pass, and the Togiak/Twin Hills area may see 3 to 3.5 inches of
rainfall from Saturday afternoon through Monday. False Pass, in
particular, may be primed to see 5+ inches of rain over the next
48 to 72 hours. Dillingham and the Western Capes from Goodnews Bay
to Platinum are still expected to see up to 2.5 inches of rain
for the same time period. Heavy rain may cause stream rises and
ponding on low lying areas along the northern Bristol Bay coast.

In addition to rain, persistent, gusty small craft to gale force
southerly winds remain forecast with the front as it pushes
eastward, eventually overspreading the Kuskokwim Coast this
afternoon. A threat for elevated surf will impact the region;
however, the highest winds are expected to peak during low tide
both today and tomorrow, and significant coastal flooding is not
expected at this time. Gusty winds to 30 mph or higher at times
are possible as far inland as Bethel through this weekend.

BL/KM

&&

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

There is very little change in thinking for the beginning of next
week through the end of the workweek. A broad longwave trough
will be situated over the western and central Bering Sea, while a
longwave ridge extends up from the North Pacific into the Gulf of
Alaska toward the Alcan Border. This general pattern looks to hold
through mid- to- late week, aiming a stream of tropical moisture
in excess of one inch of precipitable water between these
features, toward the Alaska Peninsula and Southwest Alaska. As a
result, several inches of rainfall are forecast along the Pacific
side of the Alaska Peninsula, potentially in excess of 4 inches
for some locations through Thursday. Lower amounts, broadly
speaking 1 to 3 inches are possible for mainland Southwest Alaska.
While these regions are likely to be wet for much of the long
term forecast period, there is uncertainty in the exact
orientation of the atmospheric river, so many locations will
likely see several periods of moderate to heavy rain as the
moisture plume wobbles back and forth (west/east). There is some
potential that the moist southerly flow glances parts of
Southcentral, with the Cook Inlet region and southern Kenai
Peninsula with the greatest potential to see another round of
lighter rainfall.

High pressure across the Gulf of Alaska keeps winds light and
conditions generally dry across Southcentral for the duration of
the forecast period (with the exception of the aforementioned
potential for glances of moisture intrusion). By Wednesday, the
next North Pacific low approaches the western Aleutians, bringing
gusty winds, potentially to gale force, and light to moderate
rainfall. The track of this low is particularly uncertain, but it
looks to be fairly slow moving and generally tracks along the
periphery of the Aleutian Chain through the end of the week.

&&

.AVIATION...

PANC...VFR conditions will persist through the TAF period. Light
southerly to southwesterly winds, less than 10 kts, will persist
through this afternoon before becoming more southeasterly this
evening. Southeast gusts of 12 to 18 kts could clip the terminal
at times tonight through Sunday morning. However, the core of
strongest winds will remain over Turnagain Arm.

&&


$$