150
FXAK68 PAFC 171400
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
600 AM AKDT Sun Aug 17 2025

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

Two days of calm and mostly clear weather are in store for
Southcentral as high pressure remains in place aloft and the
trough over Southeast pushes off to the south. The movement of the
trough to the south while the surface low weakens will allow
pressure gradients to relax quickly today, bringing an end to the
gusty winds that have been observed through the mountain gaps and
around Kodiak Island the past few days. Additionally, drier air
from the Interior will move in from the northwest, leading to
mostly sunny skies for many areas other than the Copper Basin,
where pockets of clouds linger. Moving into Tuesday, a shortwave
trough will push into the high, leading to increasing cloudcover
throughout the night on Monday, followed by southwesterly flow and
rain for just about everywhere but the southwest Kenai Peninsula
and Kodiak on Tuesday. Winds should remain on the lighter side
Monday and Tuesday other than some afternoon sea breezes and a
slight up-Inlet wind developing on Monday.

&&

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

Gusty winds across Southwest and the Alaska Peninsula gradually
diminish by this afternoon as a surface low in the Eastern Gulf
weakens and exits southwards. Attention then shifts to a low in
the southern Bering Sea, which will bring light to moderate rain
across the southern Bering Aleutian Islands. A shortwave from the
north moves around the periphery of the high in the eastern
Bering, increasing chances for light and isolated rain to the
Kuskokwim Delta through Monday. Gap winds increase in the vicinity
of Unalaska and Umnak islands Monday afternoon as the low departs
into the North Pacific. Overall forecast confidence is medium to
high, with lowest confidence regarding the extent and severity of
fog. This morning, fog persists across the Kuskokwim delta and
along the Aleutian chain.

KC/ER

&&

.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 and light winds will persist. Winds will
switch to southerly late this evening.

&&


$$