887
FXAK68 PAFC 052348
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
348 PM AKDT Sat Sep 5 2026

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

Improving conditions today, then trending wetter and windier
again from early tomorrow morning through early next week as two
storms move into Southcentral in quick succession. Biggest hazard
to watch today will be a slight (about 20%) chance of
thunderstorms in Susitna Valley and Copper River Basin. We`ll also
be monitoring rain amounts with the incoming storms, but don`t
currently anticipate any flooding.

Diving into the details... longwave troughing extends across the
Bering Sea and into Western Alaska, while a longwave ridge lingers
over Southeast Alaska. This is setting up southwesterly flow into
Southcentral, bringing upper-level shortwaves into our area. We`re
seeing a bit of a break this afternoon (both in winds and rain) as
a shortwave moves out of the area, but generally expect unsettled
weather as more upper level waves are on the way.

For this afternoon, a quick-moving shortwave will transit over
Susitna Valley and central to northern Copper River Basin,
bringing colder air aloft and upper level forcing around the time
of peak afternoon heating. This will bring a slight (about 20%)
chance for afternoon and evening thunderstorms.

From late tonight/early tomorrow morning through about Monday
afternoon, a robust upper level shortwave will curve up from the
North Pacific, and across Kodiak Island towards the Southcentral
Mainland. This feature has been a major source of uncertainty, as
the forecast will be influenced by how this feature phases with
other shortwaves moving through the Bering Sea and North Pacific.
While there is still a bit of uncertainty with rain amounts and
timings, forecast confidence has greatly increased since yesterday
as models are coming into better agreement. As this storm moves
in, expect winds to pick up again, mostly around Kodiak Island and
along the Gulf coast. For many, the bigger impact will likely be
light to moderate rain, with highest amounts for Eastern Kenai
Peninsula and along Prince William Sound.

Rain begins to taper off from west to east on Monday, but there
won`t be much in the way of a break as another Bering low and its
front arrive in Southcentral for the latter half of Monday and
lingers into Tuesday. The current thinking is that a swath of
small craft winds will set up east of Kodiak Islands with rainfall
enveloping most of Southcentral, including inland areas like
Anchorage, The Mat-Su, and Western Kenai.

&&


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

A long-wave trough remains firmly entrenched over the Bering Sea
and North-Central Pacific, with multiple embedded lows moving
through it. The primary storm of interest today is a gale force
low tracking south of Atka and Nikolski this afternoon. The low
ended up being a bit deeper than expected, resulting in a larger
area of Small Craft Winds with embedded smaller areas of Gales
along the Aleutians and Alaska Peninsula between Adak and Sand
Point and northward into the south-central Bering Sea. Widespread
steady light to moderate rain also accompanies this low.
Otherwise, it`s a fairly benign weather day across the remainder
of the Bering, Aleutians, and Southwest AK. The biggest impact is
to aviation, with extensive areas of low clouds and a few areas of
fog.

The general evolution of the pattern and expected weather over the
next few days still looks on track, with progressive flow and
multiple storms transiting the region. This will lead to generally
cloudy and wet weather with seasonable temperatures. However,
model guidance has been struggling with the exact track and timing
of these storms. Forecast updates today reflect some of the larger
shifts in guidance, where confidence is enough to support making
changes. The current system will track eastward along the
Aleutians and Alaska Peninsula, then transition northward into
Bristol Bay by Sunday afternoon. Expect widespread wind and rain
to accompany the low along this track. Aloft, models are in much
better agreement in depicting two out of phase negatively tilted
short-wave troughs lifting toward Southwest AK tonight through
Sunday, then exiting north and east Sunday night through Monday.
This will bring widespread rain to nearly all of Southwest during
the day Sunday, with showers lingering through Sunday night.

The next Pacific storm will arrive along the central Aleutians
(roughly Amchitka Island to Seguam Island Sunday afternoon) and
cross over to the southern Bering Sea in the vicinity or west of
Dutch Harbor Sunday night into Monday morning. It looks like the
low will hold together all the way to Southwest AK Monday afternoon.
Thus, look for another round of wind and rain with this storm as
it transits the region. It does look like a short-wave ridge will
build over the Bering Sea for Tuesday, leading to at least a day
of quiet weather. The upper level flow will remain progressive, so
expect more active weather as we continue through the remainder of
the work week.

-SEB

&&


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

A shortwave trough digging across the Gulf of Alaska Wednesday
into Thursday is still on track to bring periods of rain across
Prince William Sound and interior locations across Southcentral
Alaska. The main focus through the long term period will shift out
west as a deepening upper trough enters the western Bering
Wednesday into Thursday. Confidence continues to increase on the
associated surface low tracking north along the eastern Russia
coastline before tracking into the Gulf of Anadyr and eventually
inland across northern Alaska through the second half of next
week. A potentially gale-force front will bring gusty
southwesterly winds across the Aleutians and much of the Bering
Wednesday into Thursday, with the front reaching the Southwest
coast on Thursday. The long fetch of strong southwesterly, onshore
winds could bring the possibility of high surf and minor coastal
flooding and erosion along the Kuskokwim Delta coast as the front
progresses through the region Thursday into Friday. In addition to
gusty winds across Southwest Alaska, widespread moderate to heavy
rainfall will accompany this system as it taps into a robust
stream of Pacific moisture. By next weekend, weaker, more zonal
flow takes over the Bering while the frontal system and widespread
rain continues east into Southcentral Alaska and the Gulf.

&&
.AVIATION...

PANC...The Turnagain wind is expected to slowly diminish through
the day. Ceilings will be solidly VFR this afternoon. Ceilings
slowly drop overnight (but remain VFR) ahead of the next system.

&&


$$