175
FXAK68 PAFC 162339
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
339 PM AKDT Sat Aug 16 2025

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

A warm front extending off a weakening low tracking into
Southeast Alaska extends north into Southcentral this afternoon.
Light rain associated with this front in Prince William Sound and
the western Copper River Basin will diminish this evening as the
front weakens and the upper-level disturbance dips back south over
the Gulf of Alaska tonight. A strong pressure gradient between
high pressure in the Bering Sea and low pressure in the Gulf of
Alaska continues to drive unseasonably strong northwesterly winds
out of gaps through the coastal mountain ranges. These winds have
likely reached their peak and will gradually diminish this
evening through tonight as the low in the Gulf weakens and high
pressure nudges in over Southcentral. By Sunday morning, southerly
sea breezes make their return as synoptic flow relaxes and
sunnier skies allow for warming temperatures, reaching the mid to
upper 60s for much of inland Southcentral Alaska. Shelikof Strait
gap winds may linger a bit longer where the temperature and
pressure gradient stick around on Sunday, which will likely keep
resuspended ash from the 1912 eruption of Katmai-Novarupta blowing
across the strait to southern Kodiak Island at least through the
day, but potentially through Sunday night until northwesterly
winds relax enough to stop lifting the ash.

Calm and dry conditions continue into Sunday night, though a
trough digging rapidly across the Bering Strait into Western
Alaska causes light onshore flow on Monday. This will draw north a
bit of moisture from the Gulf of Alaska and allow for some light
upslope shower development along southern sides of mountain
ranges. Rain shower coverage increases as the trough approaches
and crosses the Alaska Range on Tuesday. Despite some timing
differences, expect a return of cooler temperatures, cloudier
skies, and rainfall, with the best chances from Anchorage north
and east. The Kenai Peninsula and especially Kodiak Island look to
escape the brunt of the shortwave`s energy and therefore see a
lower chance of rain.

&&

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

Unsettled but generally low-impact weather is forecast in the
coming days. Expect gusty winds across Southwest Alaska and the
Alaska Peninsula to gradually diminish through early tomorrow as a
surface low in the Eastern Gulf weakens and exits southwards.
Attention then shifts to several lows and shortwave troughs
transiting along the periphery of the ridge in the Bering Sea,
which will bring light rain across the Bering Sea, Aleutian
Islands, and Kuskokwim Delta through Monday. Then, a front moves
across the Western and Central Bering Sea on Monday and Tuesday,
bringing southwesterly winds to 30 kt and light rain. Overall
forecast confidence is medium to high, with lowest confidence
regarding the extent and severity of fog.

-KC

&&

.LONG TERM FORECAST (Days 4 through 7/Wednesday through
Saturday)...

The current weather pattern, dominated by Arctic influences, is
keeping the Bering Sea, Aleutians and Southern Alaska drier than
usual. However, a significant shift is expected in the extended
forecast. The previously mentioned quasi-stationary ridge,
currently over the North Pacific and Bering Sea, will push
southward, allowing a trough to develop over the North Pacific.
This will strengthen the Subtropical Jetstream and transport
moisture from the west Pacific to the Bering Sea. While there is
some model uncertainty regarding timing, all indications point to
a transition to a wetter pattern towards the end of the workweek.

Looking at the details: Tuesday and into Wednesday, an Arctic
trough will move southward across Southcentral Alaska, likely
bringing widespread rain across the area. This trough will move
out quickly by late Wednesday, as a high-amplitude high pressure
ridge builds in from the west, bringing a brief period of dry
weather. The dry spell will be short-lived due to an increasing
progressive upper-level flow. Model timing for the short-wave
troughs and low pressure systems moving in from the west is
inconsistent. Regardless, the Bering Sea and Aleutians will begin
to see a series of fast-moving systems by mid-week. These systems
are expected to reach southern Alaska by the weekend. The overall
result will be more frequent and heavier rainfall across the
region, along with a trend towards cooler daytime temperatures.

-DD

&&

.AVIATION...

PANC...VFR conditions will persist through the TAF period. Gusty
northerly winds up to 25 kts is expected this afternoon and should
diminish this evening. Winds become 10 kts or less around midnight and
will last through Sunday with northerly winds shifting light and
westerly Sunday afternoon.

&&


$$