004
FXAK68 PAFC 120026
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
426 PM AKDT Thu Sep 11 2025

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

Rain...it continues to rule the roost across Southcentral the
next few days as the forecast remains mostly on track through the
short-term.

Diving into the details: The low, which is the remnants of former
typhoon Peipah, is now just south of the Kenai Peninsula where it
will generally sit and weaken until finally dissipating on
Saturday. The feature that has a little more uncertainty is the
upper level arctic trough that is digging into Southwest Alaska
and edging slowly eastward. This feature can be seen quite well on
GOES-18 satellite imagery as the nearly straight north-to-south
edge to the clouds that stretches from the Arctic coast to near
Western Alaska Range. With cold air filtering into Southcentral
and being entrained into the low, winds are increasing through the
Kamishak Gap and bringing Gale force winds into the Barren Islands
area. Gales will diminish back to small craft Friday morning.

As the cold air aloft moves in, it is destabilizing the
atmosphere which is bringing a chance for thunderstorms along the
north Gulf coast and into the northern Gulf for this afternoon
through early Friday afternoon. The other areas with a chance for
thunderstorms will be in the northeastern Copper Basin the next
few days as there will be cold air aloft and with a few breaks in
the clouds there, it could kick off an isolated thunderstorm or
two.

One other question with this system is exactly how low freezing
levels will be as they lower over the next few days. There is a
significant amount of range (disagreement) in model solutions. The
GFS continues to be the warmest solution with NAM and Canadian
colder with respect to freezing levels. There continues to be a
chance for snow to reach the mountains down to about 4000 ft in
Anchorage and the Matanuska Valley regions Friday or Saturday. As
one goes north in the Susitna Valley, there is a chance of snow
making it down to closer to road level with Broad Pass having the
potential for snowfall late tonight and Friday night. However,
snow is not expected to accumulate, but more of a "white rain"
nature.

The forecast becomes more unclear for Sunday and the beginning of
the next work week. Another North Pacific low is poised to lift
to near the southern Gulf by Sunday. The jury remains out on how
far east or west the storm will be. The GFS/NAM/GFS Ensembles are
the strongest solutions and most west solutions. This means more
rain and wind for Kodiak Island Sunday afternoon into Monday. In
contrast, the Canadian/ECMWF and their respective ensemble
packages have a weaker storm that more east and aligned toward the
central Gulf. This would be a somewhat drier and less windy
solution for Kodiak Island Sunday into Monday. Stay tuned as
details become clearer with time on this next storm system.

&&


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

Relatively calm conditions have overspread much of the Bering Sea,
Aleutian Islands, and Southwest Alaska this afternoon. Several
weak features are producing areas of light rain showers across the
Bering Sea, while cold, dry air continues to stream south across
Southwest Alaska, Bristol Bay, and the Alaska Peninsula, with a
small corridor of gale force winds south of the Alaska Peninsula
out of Wide Bay. Gusty winds have already begun to relax for many
locations further south along the Alaska Peninsula and will
continue to diminish tonight across the region as a weakening low
in the Gulf of Alaska continues to drift east and exert less and
less influence in the area. Calming winds will allow a layer of
cold air to develop near the surface tonight for many locations in
Southwest Alaska, especially where skies are clear now or clear
out tonight. This will allow temperatures to drop to near
freezing, bringing the first frost/freeze of the season. The
current cloud cover over Southwest Alaska looks to diminish
tonight, which should allow for colder low temperatures than last
night for much of Bristol Bay, interior portions of the Kuskokwim
Delta, and portions of the Kuskokwim Valley away from the Western
Alaska Range.

Through the end of the week, similar mildly unsettled conditions
prevail as the weak features continue to drift within a broad
upper level trough. Temperatures may drop to freezing again Friday
night/Saturday morning as cold air remains in place. The one
forecast uncertainty is whether skies remain clear, and if they do
not, temperatures may rebound a few degrees. Light, remnant gap
winds hold on across the Alaska Peninsula from about Chignik north
through Saturday, but remain at or below 20 knots (~25 mph).
Heading into the weekend, the broad upper-level trough amplifies,
which induces the development of a low south of Kodiak that tracks
into the Gulf of Alaska. There is significant uncertainty in the
track of this low, and it has potential to bring north to
northeasterly winds south of the Alaska Peninsula and
precipitation along the coast with a more western track, but a
further east track would produce limited impacts. Meanwhile, cool
air remains in place over Southwest Alaska and areas of light rain
showers traverse the Bering Sea/Aleutians. Stay tuned to the
forecast for further refinements.

Quesada

&&

.LONG TERM FORECAST (Monday through Thursday)...

The active pattern continues in the long term with the main story
being a pair of lows bringing wind and rain from the Aleutians to
much of the mainland. Models are in fairly good agreement with
the main feature to begin the period as a large 980-990 mb surface
low lifts north into the Gulf for Monday. This system looks
likely to peak in intensity Monday morning as it enters the
southwestern Gulf. Heavy rain is expected along the eastern Kenai
Peninsula and northern Gulf coast Monday into Tuesday as the
frontal system reaches the coast Monday morning. Gusty northerly
winds across the Alaska Peninsula enhanced by cold air advection
on the backside of the low as well as the potential development of
a gale-force barrier jet outside of Prince William Sound ahead of
the front remain possible from the beginning of the period Monday
morning into Tuesday morning.

Further west, a series of shortwaves emerging from the Kamchatka
region and North Pacific look to merge as they enter the western
Bering, shifting the axis of the longwave trough to a more
positive tilt over the Bering. This becomes the dominant feature
in the latter half of the long term as the decaying system in the
Gulf gets absorbed, forming a large upper level low lifting from
the North Pacific towards Bristol Bay. This system reaches the
western Aleutians by Monday and tracks along and just to the south
of the Aleutian Chain and Alaska Peninsula, spreading rainfall
and elevated winds west to east across the Aleutians and AKPen
from Monday through Wednesday. Model spread and uncertainty in the
eastward extent of the track remains high at this time, but
expect rain to spread into Southwest Alaska as the low lifts
towards Bristol Bay as the front shifts east and brings another
round of rain to the Gulf late next week.

&&
.AVIATION...

PANC...Light northerly winds are expected to persist along with
nearly continuous rain as a surface low south of the Kenai
Peninsula brings showers over the mountains and into the Terminal.
Given the saturated environment and nearly continuous rain, cigs
and vis will likely remain between IFR and MVFR through this
evening, with LIFR developing after midnight.

&&


$$

779
FXAK67 PAJK 120555 AAA
AFDAJK

Southeast Alaska Forecast Discussion...UPDATED
National Weather Service Juneau AK
955 PM AKDT Thu Sep 11 2025

.UPDATE...update for 06z taf issuance.

&&

.SHORT TERM...Following the frontal passage pushing eastward
currently over the southern panhandle, are convective showers
enabled by onshore flow as the low continues lingering along the
NW Gulf coast. These showers will bring moderate rainfall with
occasional heavy rates, alongside some more gusty wind conditions
possible as showers move through. Precipitation amounts for the
southern panhandle will quickly fall after the front moves
through, though slight chances still exist through tomorrow for
shower activity. For the central and northern panhandle, which
have already begun seeing some moderate to heavy showers today,
will continue seeing rain showers tonight through tomorrow night,
with between 0.5 and 1 inch expected in the next 24 hours. Though,
there will be some variability in the precipitation amounts
depending on where the heaviest showers impact and due to
orographic effects.

The area that will see the most impacts due to showers tonight
and another wave moving up along the NE Gulf coast tomorrow is
Yakutat, which is expected to see 2 to 3 inches of rain in the
next 24 hours. This amount varies based on the high res model
looked at, with it being associated with showers, but using the
NBM probabilistic data shows an 80 to 90% chance of seeing over 2
inches and a 40 to 60% chance of seeing over 3 inches in 24 hours
through Friday evening, hence going for a higher QPF amount along
the coast. The highest rates will be tomorrow morning into the
afternoon as the next wave pushes up along the coast, with up to
around 0.10 to 0.15 inches per hour possible. For tomorrow and
tomorrow night, the majority of the higher QPF and heavier rain
rates will stay along the NE Gulf coast north of Mt. Edgecumbe.
After looking at the CAPE values expected with these convective
showers, up to around 300J/kg, there will be some slight chances
for isolated thunderstorms developing in the Gulf and up along the
NE coastline. Some may impact Yakutat, Sitka, and Elfin Cove
depending on how far they push inland, but it is unlikely for
anything to push further inland than those coastal locations.

LONG TERM...For the start of Saturday, the rain looks to continue
for parts of the panhandle, specifically for the NE Gulf coast
down towards the outer coast near Cape Spencer and potentially
down to Sitka. There is some uncertainty on the location of this
band of rain so there could be some fluctuations as it gets
closer. Farther south, deterministic models continue to disagree
on the placement of the band of precipitation. Ensembles currently
have the strongest band of rain impacting British Columbia while
places like Ketchikan could see some light rain from this band. As
we head into Sunday, most precipitation is expected to end for
Panhandle with the exception of some potential showers for the NE
Gulf coast during the overnight and early hours Sunday. Elsewhere,
high pressure looks to be over most of the panhandle bringing a
break to the area from the rains and wind seen this week. But this
break will be short lived though as the next system to impact the
area is already expected to move into the Gulf waters. There is
significant disagreement between the GFS and Euro with regards to
placement of the low as well as strength. This is also reflected
somewhat in the ensembles as well with there being a weaker
solution for the time being. Confidence in this low moving into
the Gulf and affecting the Panhandle is high but the expected
impacts is lower due to the disagreement in the models. This is
something that will need to be monitored through the end of the
week and weekend as this system has the potential to bring Gale
force winds to the Gulf waters from Cape Edgecumbe northward.
Besides the wind, ensembles are showing the potential for a good
transport of moisture northward into the Northern and Central
Panhandle. Confidence in this is around a moderate level too but
it is higher than the winds. If the moisture does move into the
area, it has the potential to bring 2-4 inches of rain to the
area. After this system moves through, high pressure returns again
before a low pressure moves into the Bering and Alaskan Peninsula
that looks to potentially impact the area for the middle of next
week. Ensemble agreement and confidence in this are low at the
time as there is disagreement for the time being.

AVIATION...6z taf issuance Light winds, lingering low-level
moisture and clearing behind the front has allowed fog and low
stratus development across the southern panhandle, with MVFR to
IFR vis/cigs possible through early morning. From Sitka on north,
showery conditions continue into Friday, with occasional MVFR
vis/cigs possible through the morning. Conditions across the
region look to improve by tomorrow afternoon, with mainly VFR
conditions expected, except for Yakutat, which looks to see steady
rain and cigs becoming IFR.

MARINE...
Outside Waters: Largely 15 to 20 kt winds continue to impact the
majority of the Gulf, with a few areas of 25 kt winds further
offshore as the low lingers along the NW coastline near Kodiak.
The SE Gulf coastline west of POW is largely 5 to 10 kts and will
stay diminished as a ridge develops over the southern panhandle
and Haida Gwaii after the front moves through. Convective showers
and associated gusty conditions are popping up across the outside
waters and up along the NE Gulf coastline, which are expected to
continue through tomorrow alongside some slight chances for
isolated thunderstorms developing. Winds along the northern and NE
coastline will pick up to 25 to 30 kt as a coastal jet develops.
The remainder of the Gulf will begin to diminish tomorrow into
tomorrow night to only 10 to 15 kt as the low weakens. 9 to 12 ft
seas tonight will diminish into tomorrow, lasting longest along
the NE coast before dropping to 6 to 8 ft by tomorrow night. W
swell of 3 to 5 ft tonight and tomorrow, with a dominant wave
period of 10 to 12 seconds expected.

Inside Waters: Majority of the northern panhandle continues to see
some moderate to fresh breezes (15 to 20 kt) this evening as the
low in the NW Gulf creates a tightened gradient with ridging
developing over the southern panhandle. Northern Lynn Canal will
continue seeing 20 to 25 kt this evening before diminishing
slowly overnight to 15 to 20 kt tomorrow. Grave Point and Scull
Island in Stephens Passage remain at 15 to 20 kt which will
diminish to 10 to 15 kt late tonight. The E-W gradient remains
particularly tightened over Cross Sound and Icy Strait, bringing
largely 15 kt E to SE winds through tomorrow evening before
diminishing into tomorrow night. The southern channels south of
Frederick Sound will remain largely light and under 10 kts
tonight and tomorrow as the ridging develops, and as the next wave
impacts mainly the northern panhandle in terms of wind impacts.
Some gusty conditions may occur following showers as they move
through tonight and tomorrow, largely in the northern and central inner
channels.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ022-053-641>644-651-652-661>664-671-
672.

&&

$$

SHORT TERM...Contino
LONG TERM...SF
AVIATION...DS
MARINE...Contino

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