449
FXAK68 PAFC 131323
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
523 AM AKDT Thu Aug 13 2026

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

The upper level high pressure ridge that has been over
Southcentral has temporarily weakened as an upper level wave has
moved up the western periphery of the ridge and is bringing
showers to the Kenai Peninsula, Anchorage and the MatSu early this
morning. After this wave moves through later today, the upper
level ridge will reassert itself over Southcentral and bring in
warmer weather for Friday and Saturday. Friday looks to be the
warmest day overall though there is a chance for isolated
thunderstorms in the northern Susitna Valley eastward into the
western Copper River Basin.

Saturday is a little more uncertain with how it will play out as
the ridge will begin to break down, but models are showing a bit
of uncertainty as to how fast this will occur. What does look
likely is that the ridge will be weaker with short waves moving
into the Coo Inlet area from the south and another short wave
approaching the northern Copper River Basin from the Interior of
the state. These waves could be the impetus for more thunderstorm
development on Saturday so that will be something to keep an eye
on.

&&

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

High pressure remains firmly in place over the Gulf of Alaska
through the short term. A broad upper low is persisting nearly
stationary over the western Bering. Between these features an
upper wave is lifting northward through Southwest Alaska with
scattered showers stretching from the Western Alaska Range to the
Kilbuk Mountains. As to be expected, Thursday will remain on the
cooler side with rain chances persisting through much of the day
for Southwest Alaska. The cooler temperatures and continued rains
will preclude any threat of thunderstorms for Thursday, but
conditions will change by Friday.

Clearing behind the departing wave of low pressure to the north
will allow for warmer temperatures and the development of
instability from interior parts of the Kuskokwim Delta down into
the Western Alaska Range late in the day. At the same time, models
continue to show a new area of low pressure tracking into the
Alaska Peninsula early Friday morning and then emerging into the
rest of Southwest Alaska by Friday afternoon. Favorable lift ahead
of the low will overspread already developing instability with
the end result being scattered showers and isolated thunderstorms.
The Western Alaska Range, the Kilbuck/Kuskokwim Mountain Ranges,
and into the Interior Kuskokwim Delta will have the best chance
for lightning activity.

By Saturday the stubborn western Bering low will finally weaken
while being absorbed in the next North Pacific low pressure system
lifting into the Aleutians. Scattered showers will likely
continue across Southwest Alaska while the previous area of low
pressure slowly lifts into the Kuskokwim Delta. For the Aleutians,
shower chances will quickly spread from west to east across the
Chain as a deepening low south of Nikolski spread a front eastward
into the Alaska Peninsula. The arrival of the low and front will
also spell renewed gusty winds from the Eastern Aleutians into the
Alaska Peninsula. Small craft winds with higher gusts are
forecast to develop late Saturday morning and persist into
Saturday night.

BL

&&


.LONG TERM FORECAST (Days 4 through 7: Sunday through Wednesday)...

By Sunday morning, a ridge will be over eastern portions of
Southcentral. An upper low and associated surface low will be in
the eastern Bering with a front pushing eastward. This front will
move into the western Gulf and Southwest coast Sunday, then move
into the rest of Southwest, Southcentral and the central Gulf
Monday into Tuesday. Conditions will be conducive for rainfall
both around the low and the front, with potentially heavy rainfall
along the front. Rain will continue into Sunday for the eastern
Aleutians and AKPen, and spreads northeastward Sunday to Tuesday
for Kodiak Island and Southwest, then Sunday night into Wednesday
for the northern Gulf Coast and Kenai Peninsula. Additionally,
small-craft to gale force winds will be persistent both along the
front and around the low, especially on Sunday. Strongest winds
will be through gaps and bays of the AKPen.

Positioning and strength of both the front and the low will
determine how far the ridge is pushed east into the Interior/Yukon
by Wednesday, thus determining when Southcentral and portions of
Southwest cool and see rain. With the front progressing from west
to east, Sunday will continue to be warm for Kuskokwim Valley and
Southcentral, especially for the Copper River Basin (high temps
up to 80 degrees). There is uncertainty on when the front pushes
the ridge out, and any additional warm days past Sunday in the
Copper River Basin will be dependent on it. Even then, a cooling
trend is expected to start on Tuesday. For the rest of
Southcentral and the Kuskokwim Valley, some rain is possible in
higher elevations of the Talkeetna Mountains and along the Alaska
Range. Though most locations at lower elevations remain dry,
increased cloud coverage will begin the trend of slightly cooler
temperatures. As the front moves deeper into Southwest and
Southcentral Sunday night into Monday, lighter precipitation will
spill over the mountains into more interior locations (Kuskokwim
and Susitna Valleys). High temperatures drop to at most the low
70s by Monday and upper 60s by Tuesday as more widespread rain
looks to fill in.

The low in the Bering becomes vertically stacked on Monday and
looks to stall through at least Wednesday as it slowly weakens.
Small craft winds likely persist in the Bering through Wednesday.
Additional shortwaves look to rotate around the low into Southwest
and possibly as far as western Southcentral. This would lead to
prolonged widespread precipitation into the middle of the week.
Models are still uncertain on precise timing of each wave and
where the heaviest rainfall will be, but the general pattern hints
at a wet beginning of the week for most of Southwest and much of
Southcentral outside of the Copper River Basin.

-PA

&&


.AVIATION...

PANC...There is an upper level wave moving up Cook Inlet which is
bringing showers to the area early this morning. In spite of the
precipitation, these showers have helped to mix out the stagnant
low-level inversion that has been over the area for a number of
days and brought in the haze and MVFR ceilings. By this afternoon,
the shower activity should subside with VFR conditions then
expected through Friday.

&&


$$