Kenai, Alaska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

594
FXAK68 PAFC 200634
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
1034 PM AKDT Mon Oct 19 2026

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

Key Messages:

- A large storm system will bring widespread rain and snow to most
  of Southcentral tonight through Tuesday night.

- Multiple Winter Weather Advisories are in effect for snow
  including for Broad Pass until 10 pm this evening; and Thompson
  Pass, Western and North Copper River Basin until 4 am Wednesday
  morning.

- A new Winter Weather Advisory is now in effect for the Anchorage
  Hillside from 10 pm this evening through 10 pm Tuesday.

Discussion:

A complex and active weather pattern continues to unfold across
the Gulf and to the north across Southcentral this afternoon. A
large plume of moisture is spreading northeast into Southcentral
along a belt of stout southwest flow situated between a deep
trough out west and a strong ridge over the Northeast Pacific. A
shortwave trough that pushed into the region from the southwest
earlier today is beginning to move off towards the northern Alaska
Range, while an associate surface front approaches the north Gulf
Coast. A fierce barrier jet moving along and ahead of the front
has been producing easterly wind gusts close to storm force near
Hinchinbrook Entrance and just offshore from Cordova. Widespread
precipitation also continues to overspread much of the region,
with mostly rain now falling at sea level along the coast.
Widespread higher elevation and mountain snow is continuing across
nearly all of the interior parts of Southcentral, where a number
of Winter Weather Advisories are either in effect or set to go
into effect shortly. Much of the Susitna Valley is also still
seeing mainly snow, where temperatures have been cooler compared
to areas farther southeast.

Looking forward towards tonight onwards, there are a number of
key forecast changes and details that have shifted compared to
indications from the past day or so. Models have struggled
considerably to hone in the the track and forward speed of a new
low and shortwave trough now taking shape south of the AKPen, but
we are finally seeing solutions come into better alignment today.
It now looks like the new low developing near the Gulf will move
northeast towards Prince William Sound much faster compared to
prior indications, likely reaching the Sound by early Tuesday
morning instead of Tuesday afternoon. This shift has a number of
implications for expected timing, type and duration of additional
precipitation expected near and out ahead of this secondary
approaching system. The most notable change to the forecast was to
clear heavier rain/snow out of the Kenai Peninsula and Susitna
Valley much earlier in the day on Tuesday due to the faster
progression of the Gulf low. The low also will not have as much
time to deepen out over open water before it begins to interact
with steep terrain along the coast, so marine winds will not only
peak earlier in the day tomorrow, but also remain on the weaker
side compared to earlier expectations.

In terms of the impacts from anticipated heavy precipitation and
snowfall, timing for the heaviest rates has also shifted earlier.
It now looks like the heaviest precipitation will fall during the
morning hours on Tuesday as the incoming trough and attendant low
reach the coastline, including just about everywhere aside from
the western Susitna Vally, where things will dry out by this
evening.

There is increasing concern that the "wet bulb effect" could play
a role in precipitation type at lower elevations overnight
tonight into Tuesday morning. As precipitation intensity picks up,
melting snow falling into the column could help low level
temperatures cool enough for cold rain to switch over to wet snow,
including across parts of the Mat Valley, western Kenai Peninsula
and Anchorage Bowl. Snowfall amounts along this corridor remain
highly uncertain, with amounts depending on when rain transitions
to snow overnight tonight and how long precipitation stays snow
through Tuesday evening. Parts of the Anchorage Bowl and Mat
Valley could see several inches of slushy accumulation, mainly on
elevated and grassy surfaces. Snow will probably struggle to
consistently stick on roadways close to sea level, mainly due to
the still seasonably warm ground temperatures. At higher
elevations and where temperatures will remain colder, much higher
storm total snowfall amounts remain on track. An additional 6-12"
is expected across much of the Anchorage Hillside and along the
Glenn Highway from Sutton east to Tolsona. Even higher additional
amounts on the order of 12" or more are expected near the top of
Thompson Pass and along northern parts of the Richardson Highway
near Paxson.

By late Tuesday into Wednesday, snow will let up as a lingering
upper level trough drifts slowly southeast towards the Copper
Basin and northern Gulf and as a cooler air mass filters in from
the northwest. Gusty northwest gap winds will linger across the
western Gulf through Wednesday as the then weakening low drifts
east across the Gulf while northwest flow continues to pull cool
air across the AKPen. Meanwhile, overnight lows across the bulk of
Southcentral will be much colder Tuesday night and Wednesday
night, dipping into the 20s to low 30s in most spots, perhaps
even colder for areas that end up seeing the highest snowfall
totals through Tuesday evening. Cool and dry conditions will
persist into Thursday as a developing upper ridge begins to
encroach onto Southcentral from the west.

-AS

&&


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

Key Messages:

* Southwest Alaska: Scattered snow and rain showers, with areas
  of fog. Breezy and trending colder for Tuesday and Wednesday.

* Aleutian Islands and Alaska Peninsula: Scattered rain showers.
  Breezy Tuesday and Wednesday.

* A strong low pressure system moves east across the Bering Sea
  beginning Wednesday evening. Confidence is very high that the
  strongest winds will be at least gale force (>= 34 kt or 39
  mph).

Discussion:

The most notable short-term forecast updates were to increase
winds around Unalaska, increase snow chances and amounts for parts
of Southwest Alaska, and add fog to the forecast for Southwest
Alaska and the Alaska Peninsula. Otherwise, the weather through
Wednesday afternoon looks fairly low-impact for the region. The
main feature of concern over the next 3 days will arrive later
this week, as a strong low pressure system starts to move into the
Bering Sea and towards Southwest Alaska. This storm will bring
with it warmer air, moderate to heavy rain, and strong southerly
winds.

&&


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

Key Messages:

* A series of strong storms move across the Bering Sea and into
  Alaska from Friday through the weekend, bringing strong winds
  and heavy precipitation.

* Though confidence is low in exact impacts at this time, strong
  onshore winds and elevated coastal water levels are a concern
  for Southwest Alaska, mainly Friday and Saturday and again on
  Monday.

Discussion:

The biggest story in the long-term forecast will be a strong low
transiting from the Kamchatka Peninsula to Alaska. Ensembles are
in relatively good agreement with this storm, with seemingly
higher-than-average forecast confidence given that this feature is
4 to 7 days out. Good run-to-run consistency among deterministic
global models is also contributing to higher-than-average forecast
confidence. The areas of highest agreement with this feature are
for gale to storm force sustained winds along the front as it
moves across the Aleutian Chain, the Southwest Alaska coastline,
and the Alaska Peninsula. These onshore winds are raising
concerns for coastal impacts (including high surf and perhaps even
coastal flooding) for south-facing portions of the Western coast.
It`s still too early to say for now what projected water levels
will be, but we will be closely monitoring this storm.
Southcentral should be spared the worst of the winds with this
storm, as the front will very likely be weakening by the time it
exits Southwest Alaska.

In addition to winds, there will also be plenty of moisture along
the front, which will bring periods of moderate to heavy
precipitation to the Aleutians, Alaska Peninsula, and Southwest
Alaska. Precipitation amounts are uncertain at this time, as
overall amounts will be dependent on where the front may slow down
and linger as upper waves move through. Given the strong winds
associated with the front, there will likely also be areas of
downsloping that will reduce precipitation totals. While warm air
advection will likely keep precipitation mostly rain for the
majority of Southwest Alaska, colder air lingering in Southcentral
could mean that lower elevation areas may see snow.


&&

.AVIATION...

PANC...Not a straightforward forecast with a series of low
pressure systems moving across the region. Generally MVFR cigs
expected through the TAF period except for a drop to IFR during
the overnight. Have carried LLWS in the TAF this past afternoon
(Monday) but will leave out from this evening onward with winds
from 2-5kft diminishing. Winds at the surface will remain under
10kts through tonight, becoming somewhat gusty by around 14z.
Precip type is also tricky. Expect mainly rain for the PANC
terminal with a mix or change over to snow late tonight into
tomorrow morning. Also expecting periodic changes between rain-
snow throughout Tuesday. Little if any accumulation is expected at
the airport.

&&


$$