872
FXAK68 PAFC 220157
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
457 PM AKST Fri Feb 21 2025

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

Discussion:

The Gulf will remain active through the weekend as several
systems rotate northwards from the northern Pacific. These systems
will continue to bring mostly rain to the lower elevations and
snow for the higher elevations of the coastal mountains.

The trough associated with the precipitation across the coastal
region throughout the day today continues to move inland over
Southwest Alaska, continuing upslope precipitation along the
Alaska Range and scattered rain showers for the Eastern Kenai
Peninsula and Prince William Sound. Gusty winds in Prince William
Sound and Turnagain Arm will continue to weaken throughout the
evening as the gradient relaxes with the low retrograding back
towards Bristol Bay. Although winds are expected to remain
relatively calm throughout the weekend, the exiting system will be
quickly replaced as the next system lifts into the northern Gulf
coast by Saturday morning. Some uncertainty remains with this low
as it likely enters the Gulf having a double center, with one
becoming nearly stationary in the western Gulf near Kodiak Island
and the other working up along the eastern Gulf coast and carrying
the bulk of the moisture associated with the system. As the low
nears the coast, the majority of precipitation will continue to be
along the the eastern Kenai Peninsula for Saturday and then
widespread across the entire northern Gulf coast for Sunday. As
the system progresses Sunday night into Monday, some model
guidance is in favor of the trough swinging northwards across
Southcentral, potentially bringing a brief shot of rain and snow
to Anchorage and the Mat-Su Valley, though the lack of model
agreement keeps confidence in this scenario low at this time.
Regardless of the track that ultimately plays out, the Gulf looks
to remain unsettled through early next week.

-JH

&&


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

A broad, disorganized upper level trough with several embedded
small low pressure systems continue to drift over much of the
Bering Sea and Southwest this afternoon and evening. This is a
fairly consistent pattern, with little changes expected over the
next few days, maintaining the benign, unsettled pattern over the
area now. Very weak flow, both at the surface and aloft, is
translating to only slight movement of multiple weak lows embedded
in the large scale trough in place. One of these lows is still
drifting over the western Bering, and this feature will continue
to wobble in place in the same vicinity for the next few days.
Another small, weak low is drifting slowly north, currently just
south of Kodiak Island. Low temperatures for Southwest Alaska will
likely remain near the mid-to-upper 20s for Bristol Bay, and near
10 for the Kuskokwim Delta and Lower Kuskokwim Valley.

Conditions over the Bering will remain unsettled with the complex
low center in the Western Bering overspreading rain/snow showers
mixed with areas of clear skies across the Aleutians. Winds will
generally stay quite weak as the low moves past, generally under
small craft range. Meanwhile, an inverted trough axis will cross
over the Alaska/Aleutian range from the east later today into
tonight, supporting another round of light rain/snow focused
primarily over central and northern portions of Bristol Bay.
Temperatures region- wide will stay mostly in the 20s and 30s
through the weekend, with a slight trend towards cooler
temperatures across Southwest by Sunday. Areas where showers
develop expected to see a mix of rain and snow produced, however
these systems would likely be showery in nature with no
significant accumulations expected. One exception may be coastal
Bristol Bay tonight, near Dillingham, that may receive up to an
inch of snow before the precipitation comes to an end by Saturday
afternoon.

-CL/AS

&&


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

A broad upper level low stretches across the Bering, with the
convoluted flow pattern due to shortwaves rotating through the
system becomes smoother by the end of the forecast period. These
shortwaves briefly flatten a building ridge across Western Canada
into Interior Alaska through Wednesday. A couple of low centers
aloft slip over the Bering through the week, supporting active
weather across the region. A pair of Eastern North Pacific lows
bring weather across Southcentral Alaska throughout the forecast
period. A well developed North Pacific low will increase the
weather intensity over the Aleutians and Alaska Peninsula by the
end of the week.

Some upper disturbances drive areas of rain, rain and snow or
snow over the open Bering through Friday. In the East, a moderate
low brings widespread rain from the AKPEN across Kodiak Island on
Tuesday, and extending over the Southcentral coast with more
moderate precipitation on Wednesday, and continuing through
Friday. Some areas of snow will occur inland and over higher
elevations. This low will dissipates Thursday. A second well
developed North Pacific low spreads snow up to the Pribilofs and
Northern Bering Thursday, changing to locally moderate rain and
gusty winds from the Central Aleutians into the AKPEN on Friday.

- Kutz

&&



.AVIATION...

PANC...High confidence continues for VFR conditions and light
northerly winds will persist. Ceilings could drop below 5000 ft on
Saturday morning as a Gulf low approaches Southcentral. There is a
small chance for light snow or flurries later on Saturday.

&&


$$

154
FXAK67 PAJK 212313
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
213 PM AKST Fri Feb 21 2025

.SHORT TERM...Another front and associated low is moving north this
afternoon bringing strong winds and rain to the Inner Channels.
As of the time of writing, places across the southern panhandle
have started to report rain as well as some gusty winds as the
front moves over. With warm temperatures across the area as well
as this storm originating from farther south, any precipitation
that does fall is expected to remain as rain with the exception
locations at elevation which could see some snow accumulations. As
this system moves into the gulf, another front wrapping around
the low will move into the area Saturday afternoon into Saturday
night. This will bring a reinforcing shot of winds and rain to the
area with the heaviest precipitation expected across the southern
panhandle.

.LONG TERM...Continued active pattern for the foreseeable future (essentially
until the end of next week) with multiple shortwaves troughs and
ridges moving over the eastern gulf, resulting in multiple systems
with small breaks in between. Whether good news or bad,
precipitation type looks to stay predominantly rain for the sea
level areas, with upper elevation roads in the northern panhandle at
risk of some snow development.

Sunday through Monday will see a system move up from the south,
bringing moderate to fresh breezes from the southeast and light to
occasionally moderate rainfall. No changes were made to the QPF
forecast, and minor changes were made to the marine forecast, mainly
to lower wind speeds in areas which are sheltered to a SE wind.
Monday night sees a transient ridge move over the panhandle,
bringing lighter winds and some fog potential. Kept fog chances over
land areas in the northern half of the panhandle as confidence is
not high on lower wind speeds over marine waters. It may very well
develop as a low stratus deck instead of proper fog.

Tuesday into Wednesday sees a possibly more impactful system moving
in from the south. Currently, the main source of uncertainty comes
from aloft directing flow, which seems to be bimodal in nature. The
first, more likely solution at around 60%, sees the directing flow
towards the southern panhandle. The second, directs the energy south
of the panhandle and toward Haida Gwaii. NAEFS ensemble guidance
with respect to climatology has surface winds around the 90th
percentile, and EPS EFI guidance has roughly 60% chance of seeing a
wind gust event greater than 60 mph in the southern panhandle. While
this is mainly focused over the marine areas, such as southern
Clarence Strait and Dixon Entrance, will continue to monitor the
potential going forward. Similarly for precipitation, the more
likely solution has higher rain totals at around 1.0-2.5 inches in a
24 hour period.

&&

.AVIATION...Advancing front with lowering CIG and VIS for southern
area airports dropping from MVFR to IFR for brief periods. Northern
areas kept mid level cloud deck and VFR conditions. Surface winds
picked up and LLWS developed for locations south of Frederick Sound
due to the front. Expecting steady state through the evening and
overnight then improving conditions as the low weakens and exits the
area through the day Saturday.

&&

.MARINE...A gale force front continues to work northward this afternoon
bringing gusty winds and increased seas to the Inner Channels as
well as the outer coast waters. Combined seas along the outer coast
are expected to remain in the 10-15 ft range although an area of
larger seas could be possible with the strongest winds. For the
Inner Channels, passages that are oriented more North to South will
have higher seas with the front passing through. East to West will
have lower seas but could still see some significant seas,
especially for places like Cross Sound.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Strong Wind until midnight AKST tonight for AKZ328-330.
Strong Wind from Saturday morning through Saturday afternoon for
AKZ330.
Strong Wind until 3 PM AKST this afternoon for AKZ332.
MARINE...Gale Warning for PKZ641-661-662-664.
Small Craft Advisory for PKZ022-033>036-053-642>644-651-652-663-
671-672.

&&

$$

SHORT TERM...SF
LONG TERM....NC
AVIATION...PRB
MARINE...SF

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