Kenai, Alaska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

910
FXAK68 PAFC 151328
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
528 AM AKDT Sat Aug 15 2026

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

The pattern change is underway as the upper level ridge that has
been the source of the warm and often sunny weather the past few
days is moving eastward in response to a large upper level trough
digging into the Bering Sea and merging with a low south of the
Aleutians. Therefore expect cloud cover to increase today across
Southcentral. There remains a chance for a thunderstorm this
afternoon into early evening for the northern Susitna Valley and
northern Copper Basin. However, thunderstorm activity is expected
to be less than yesterday.

The big change gets going tonight as the front associated with
the Bering Sea low will move across Kodiak and then up Cook Inlet.
This front will bring more rainfall into Kodiak Island by this
evening and then coastal Southcentral tonight with the rain
spreading into more protected areas such as Anchorage and the
Susitna Valley on Sunday. The Copper River Basin will remain drier
due to downsloping from the strong southerly winds.

On Monday, the upper level flow will turn more southwesterly due
to the main upper level low pushing into Southwest Alaska. This
will bring more rainfall especially to the Susitna and Matanuska
Valleys and probably Anchorage and the northern Kenai Peninsula
as well. The gusty gap winds will likely persist through Monday as
this pattern is favorable for them for Turnagain Arm, Knik River
Valley an along the Copper River.

&&

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

A transition toward cooler and wetter pattern is underway across
Southwest Alaska as the upper-level pattern becomes increasingly
dominated by a deep low moving out of the North Pacific. Any
lingering showers across the Southwest Mainland today will become
increasingly tied to shortwaves lifting northward ahead of the
main system. Thunderstorm potential will continue to decrease as
cooler, more stable air begins to move into the region.

The main upper-level low lifts northward toward the Alaska
Peninsula and Southwest Alaska through Sunday. Numerous shortwaves
rotating around the low will move across the AKPEN and SOuthwest
Mainland, supporting periods of rain. Rain will increase across
the AKPEN first before spreading northward into Bristol Bay and
the Kuskokwim Delta. Rain becomes more widespread across Southwest
Alaska Sunday, with periods of moderate to locally heavy rainfall
possible as stronger shortwaves rotate around the upper low.

By Sunday night into Monday, the upper low moves farther into
Southwest ALaska while gradually becoming broader and more
elongated. additional shortwaves rotating around the circulation
will maintain periods of rain and showers across much of the
Southwest Mainland. The most persistent rainfall will gradually
shift north and east with the upper-level circulation, while
precipitation becomes increasingly showery farther south and west.
Cooler temperatures will accompany the system, marking a return to
a more typical cool and wet August pattern.

Across the Aleutians and Bering Sea, unsettled conditions will
continue as the North Pacific system tracks northward. Rain and
gusty winds spread across the eastern Aleutians and AKPEN before
conditions gradually become more showery behind the system.
Farther west, another weak disturbance moving out of the western
Bering may bring additional showers to portions of the central and
western Aleutians late in the period.

Model guidance remains in relatively good agreement with the
overall evolution of the upper-level pattern through Monday,
though differences remain in the exact position and strength of
individual shortwaves rotating around the main low. These
differences will influence the timing and location of the heaviest
periods of rainfall across Southwest Alaska.

LM

&&


.LONG TERM FORECAST (Days 4 through 7: Tuesday through Friday)...

By Tuesday morning, there is general agreement of a vertically
stacked low being over the Lower Yukon Valley. Troughing extends
down through the Aleutians, with the most significant shortwave
outside of the low being over the western Aleutian Chain. Models
hint at shortwaves continuing to rotate around the low as it
continues northward into the Interior. This will maintain chances
for precipitation for much of the southern Mainland Tuesday.
Specific timing of these waves is unknown, but the heaviest
precipitation is expected to fall along coastal regions of the
Northern Gulf Coast/Prince William Sound and along the Alaska
Range in the western Susitna Valley. Out west, the Aleutians and
Bering likely see showers Tuesday as the shortwave moves east.
The shortwave over the western Aleutians becomes a closed low over
the eastern Aleutians by Tuesday evening. This looks to pull
additional moisture in and bring another round of rain for the
eastern Aleutians, Southern AKPen, and Kodiak Island Tuesday night
through Wednesday. This low crosses the southern AKPen into the
Gulf Wednesday morning and moves into the Alaska Panhandle on
Thursday. As the low moves through the Gulf on Wednesday,
rainfall will likely shift to the northern Gulf Coast east of
Prince William Sound with some spilling over into interior
locations of Southcentral. Models diverge with resolving certain
surface features (mainly whether or not a surface low develops in
the Gulf on Wednesday). If a surface low develops in the Gulf
Wednesday, rainfall may be enhanced along the northern Gulf coast.
Some southeast gap winds (Turnagain, Knik, and Copper River
winds) may be enhanced as well on Wednesday. These details will
become more clear in the coming days.

To the west of the lows, models diverge on solutions between
zonal flow and attempts at a ridge building in the Bering with
additional shortwaves traversing into the southern Mainland.
Either pattern would support cooler temperatures and mostly overcast
skies across much of southern Alaska and the Bering with
continued chances for precipitation across the southern Mainland.

-PA

&&


.AVIATION...

PANC...VFR conditions will persist through the period, though
ceilings may lower to under 5000 ft starting this afternoon with
an approaching frontal system. This system will bring rain to the
area overnight, though there is a question as to how much will
make it to the terminal in the cross-barrier flow over the Chugach
Mountains. The best chance for rain and a MVFR ceiling will be
late tonight into early Sunday morning.

Winds should remain southerly to westerly today into tonight but
remain at or under 10 kt through Sunday morning.

&&

$$