Kenai, Alaska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

282
FXAK68 PAFC 251354
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
554 AM AKDT Fri Sep 25 2026

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

Key Message:

- Strong, southeast gap winds return to Southcentral as a gale
  force front lifts across the northern Gulf and through
  Southcentral.

- One to three inches of rainfall is expected for most communities
  along the Northern Gulf coast, Kodiak Island, and Prince William
  Sound by Sunday morning. Western Prince William Sound will see
  locally higher amounts.

- Much less rainfall is expected farther inland. Western Kenai
  Peninsula could see 0.2 to 0.7 inches and Anchorage through the
  MatSu, a quarter of an inch or less. Amounts for these
  communities will depend on how much rainshadow effect/downslope
  drying they experience.

Discussion:

A gale force front extending from a very strong Bering low with a
corridor of moderate to heavy rainfall is lifting north across
the Gulf this morning. Cloud cover ahead of the front has steadily
spread across Southcentral.

Coastal ridging is on track to build ahead of the front across
the northern Gulf coast, which will lead to increasing gap winds
for the Copper River Basin, Knik River Valley, and Turnagain Arm
as pressure gradients tighten. The Knik River Valley wind is the
area of the biggest uncertainty Friday afternoon as there is a
chance that a few elevated wind gusts move into Palmer, but some
models show that the strong down-inlet component to the wind
prevailing and essentially bending the wind direction southward
before making it into the Matanuska Valley. Due to the parent low
location out west signaling down-inlet flow, the Anchorage Bowl
seems to be less of a concern than the Hillside, where at
elevation wind gusts will be ticking up to 50 mph. Overall
consensus remains short of Wind Advisory criteria for the
Hillside. Current forecast confidence is still in the medium range
(about 55 to 65 percent) for Hillside wind gusts. Higher profile
vehicles may struggle with those gusty winds on the Seward Highway
along the Turnagain Arm, especially later today into Saturday
morning as the highway could become clipped with strong wind gusts
though the Arm. The low location out west will be a key factor in
determining the extent of impacts from the Turnagain Arm winds,
and there is no real indication in the models of the Bering low
driving north of 60N, where in doing so would bend winds more into
west Anchorage, but that chance right now is low (20 percent).

Through the short term, periods of locally heavy rain are
expected with strong orographic lift along the eastern Kenai
Peninsula. By Sunday morning, Seward, Cordova, Valdez, and the
eastern portions of Turnagain Arm are on track to see 1 to 3
inches of rainfall. In contrast to coastal locations,
southeasterly winds ahead of the front will create a "rain shadow"
effect in lee of the mountains for the western Kenai Peninsula,
Anchorage Bowl, the MatSu, and Copper River Basin, keeping these
areas mostly dry through Saturday morning. As the front continues
north, however, some of the energy could push moisture northward
up the Cook Inlet, bringing periods of brief, light rainfall to
Kenai, Anchorage, and the MatSu Saturday afternoon through Sunday.
The pressure gradient will show signs of gradual relaxing
Saturday night through Sunday morning, but strong winds will
continue to push east to southeast winds into Prince William
Sound.

-AM/Rux


&&


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

Key Messages:

* A strong and expansive Bering Sea low continues to bring strong
  winds and high seas to much of the Bering Sea and Aleutians
  today, with another round of strong westerly winds affecting
  portions of the Aleutians and Alaska Peninsula through Saturday.

* Strong winds across Southwest Alaska gradually diminish as the
  system moves inland and weakens, though periods of rain and
  showers continue.

* For Southwest Alaska: High Wind Warnings are in effect for the
  Western Capes. The Coastal Flood Warning remains in effect with
  the primary communities of concern being Kwigillingok/Kongiganak
  and Kipnuk, and communities near and along the mouth of the
  Kuskokwim River. A Flood Watch also remains in effect for the
  interior Kuskokwim Delta, for areas near Bethel.

Discussion:

A vertically stacked low over the Bering Sea remains the dominant
feature across the region this morning. The upper-level
circulation is readily apparent in the 500 mb pattern, with
several lobes of enhanced vorticity rotating around the broader
circulation. At the surface, the low remains quite deep (~967 mb),
while the associated front continues to progress inland across
Southwest Alaska. Although the system has reached maturity, a
tight pressure gradient surrounding the low will maintain strong
winds across a large portion of the Bering Sea and Aleutian Chain
today.

For the Bering Sea and Aleutians, strong southwesterly to westerly
flow continues today on the southern side of the low. The first
surge of the strongest winds has already moved through portions
of the central and eastern Aleutians; however, another potent
shortwave wrapping around the southern side of the parent
circulation will reinforce the pressure gradient and bring another
increase in winds. This will be particularly noticeable from the
central Aleutians eastward toward Unalaska and the Alaska
Peninsula. Storm-force winds remain possible in portions of the
Aleutians waters, with widespread gales elsewhere. Large seas
will remain a significant concern, with seas generally in the
20-foot range and locally higher across the central and eastern
Aleutians.

Through tonight and into Saturday, the upper-level low begins a
slow eastward progression while remaining centered over the
eastern Bering. The 500 mb guidance shows additional shortwave
energy rotating around the southern and eastern periphery of the
circulation. As this energy rounds the base of the trough, another
push of strong west to southwest winds spread from the central
Aleutians toward the eastern Aleutians and Alaska Peninsula. Thus,
while some locations may experience a temporary decrease in winds,
the overall pattern remains quite active through much of Saturday.
Winds will gradually turn more westerly behind the low and
associated trough.

For Southwest Alaska, the main frontal band continues to move
inland today, with rain accompanying the front across the
Kuskokwim Delta and Bristol Bay region. Winds gradually shift from
southeast to south and southwest following the frontal passage.
The strongest winds along the immediate coast will slowly decrease
as the front moves farther inland, though gusty conditions will
persist, particularly along exposed coastal locations and through
terrain-favored areas. Farther inland, rain becomes more showery
as the deeper moisture associated with the front pulls north and
east.

Attention also remains on elevated water levels along portions of
the Kuskokwim Delta coast. The prolonged onshore flow associated
with this system has pushed water toward the coast, and elevated
water levels will remain possible until winds sufficiently turn
offshore and diminish. The previous forecast highlighted the
Kwigillingok/Kongiganak and Kipnuk areas, as well as communities
near the mouth of the Kuskokwim River, as areas of particular
concern. The progression of the low and timing of the wind shift
will determine how quickly water levels begin to subside.

By Saturday afternoon and Saturday night, the overall system
begins to lose some organization. The upper low becomes
increasingly elongated as shortwave energy rotates around and
eventually away from the parent circulation. This should allow the
surface low to gradually fill while the pressure gradient begins
relaxing from west to east. Westerly winds will nevertheless
remain elevated across the eastern Bering, eastern Aleutians and
Alaska Peninsula into Saturday evening.

The weakening trend becomes much more apparent by Sunday. The
guidance depicts the upper circulation becoming broader and less
defined as it shifts toward Southwest Alaska and the Alaska
Peninsula. Heights begin to rise over the western and central
Bering behind the departing trough, while the strongest mid-level
flow becomes displaced farther south and east. At the surface, the
weakening low and relaxing pressure gradient will allow winds to
continue diminishing across the Aleutians and Bering Sea.

That said, Sunday will not necessarily be completely quiet.
Cyclonic flow aloft and lingering low-level moisture should
support scattered showers across portions of Southwest Alaska,
the Alaska Peninsula, and eastern Aleutians. Northwesterly winds
will also persist behind the departing system, particularly
across the eastern Bering and Bristol Bay. Seas will subside as
the long-duration westerly fetch weakens.

Overall, the forecast trend remains toward continued strong winds
and rough seas today into Saturday, followed by a more pronounced
decrease in winds and seas Saturday night through Sunday as the
Bering low fills and the upper-level circulation weakens.

LM


&&


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

The long term begins late Monday with the longwave trough axis
moving east and extending from the Al-Can border south to the
eastern Gulf of Alaska. The result is low pressure over the Gulf
with showers and winds wrapping around the low and across the
immediate Southcentral coast. This feature will continue to move
east toward the Alaska Panhandle for Tuesday, with northwesterly
flow aloft and at the surface in the wake of the low and the
upper-level trough. The northwesterly flow will advect weaker
waves from northwest Alaska across interior Southwest and
Southcentral, allowing for periods of rain showers and higher
elevations snow showers along the mountains and across the Copper
River Basin Tuesday into Wednesday. Northwesterly gap winds will
also pick up along the coast across the Barren Islands through
this same time period. A stronger upper-level shortwave deepens
into an upper-level low as it drives across the Southern Mainland
for Thursday keeping showers, gap winds, and colder air in place.

Farther west, strong northwesterly flow over the eastern Bering
and AKPen weakens as the aforementioned waves move east. A ridge
of high pressure settles over the western Bering and Aleutians
Monday and moves east through Tuesday as a Kamchatka Low moves
toward the forecast area with a gale-force front swinging out
ahead of it. The front reaches the western Aleutians by late
Tuesday moving to the eastern Aleutians by late Wednesday. Model
agreement then wanes with respect to how quickly this front and
its parent low move east across the Bering and Aleutians.
Whatever the solution, conditions for these areas look to remain
unsettled with steady rain and wind through much of the latter
half of next week.

-TM


&&


.AVIATION...

PANC...There is some uncertainty to the duration of LLWS
throughout the TAF period as gusty, southeast winds through
Turnagain Arm could make it over the terminal. Otherwise, light
and variable winds at the surface will shift northwesterly at
times beneath continued southeasterly flow aloft. VFR conditions
will persist through the TAF period.

-BL


&&


$$