Graphical Hydro Meteorological Discussion

018
FXAK68 PAFC 070123
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
423 PM AKST Sat Dec 6 2025

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

Key Message: Weather continues to remain active across
Southcentral Alaska with the threats of snow, blowing snow, strong
winds, and dangerously low wind chills through the end of the
weekend. The cold airmass will be with us well beyond the end of
the short term.

...Active Warnings and Advisories...

- A Winter Weather Advisory has been issued for Northeast Kodiak
Island, including Kodiak City, Ouzinkie, and Port Lions through
3PM Sunday for 3 to 6 inches of snow and blowing snow. Winds
gusting up to 50 mph are possible. Visibilities reduced to one
half mile or less at times.

- A High Wind Warning remains in effect/has been extended for the
Matanuska Valley through 1PM Monday for 35 to 55 mph winds with
gusts up to 90 mph.

- A Wind Advisory remains in effect/has been extended for
Anchorage and the NW Kenai Peninsula through 1PM Monday. North
winds of 20 to 30 mph with gusts to 55 mph expected. Strongest
winds expected along the Knik Arm from Birchwood southwest,
across North and West Anchorage, and along the coast of the
northern Cook Inlet, including Kenai and Nikiski.

- A Blizzard Warning remains in effect for Thompson Pass until 6AM
Sunday for blizzard conditions and up to 1 inch of snow. Winds
could gust as high as 60 mph.

- A Blizzard Warning remains in effect for Broad Pass, Richardson
Highway from south of Isabel Pass to Paxson, and along the Tok
Cutoff from Mentasta Pass to north of Gakona through 9PM Sunday
due to blizzard conditions due to blowing snow with winds
gusting to 50 mph. Wind chills dip as low as 15 to 25 degrees
below zero, falling further to 25 to 40 degrees below zero by
Sunday.

As of 3PM this afternoon, the Matanuska Valley has well exceeded
high wind criteria as advertised yesterday in the issuance of the
High Wind Warning. The highest gust recorded so far today for
Palmer is 84 mph at 9:53AM, with more strong wind gusts to come
through the rest of today and tomorrow. More than 20,000 people
across the Matanuska Valley are currently without power. A highly
amplified 500 mb pattern characterized by an arctic trough and
upper low and that has dug well southward over the Gulf along with
ridging across the northern Bering and points northward has led
to a powerful jet that has been screaming over the Matanuska
Valley, and is oriented in a way that the Glenn Highway, west
Anchorage, and the western fringes of the northwestern Kenai
Peninsula have been clipped by gusty winds as well. A low level
jet is also evident, mostly driven by a strong thermal/pressure
gradient at the surface, and thermal/thickness gradient aloft
between the Copper River Basin and the valleys to the west.
Blowing and drifting snow have also been observed in these areas
as well today, so much so that the Palmer ASOS has been
erroneously reporting light snow all day with clear skies. With
such windy conditions, temperatures are running about 5 degrees on
average warmer than guidance due to a well mixed boundary layer.
When winds finally begin to subside, the expectation is that
temperatures drop off as well.

At least for the short term, the forecast will be mainly tuned to
the remaining snowfall across the area, blowing snow, drainage
gap winds, and brutally cold air and wind chills. The arctic
airmass has fully engulfed Southcentral Alaska, with considerably
cold air making it all the way southward to the Gulf coast.
Looking at radar and surface observations, snow showers, wind, and
squalls have overspread the southern portions of Prince William
Sound, Cordova, and the Copper River Delta. This is due to a
compact surface low in the Gulf west of Middleton Island that has
aligned with upper level divergence from the aforementioned
trough, and shortwaves being ejected northward from the trough
envelope. It looks like this surface low will retrograde and
continue to drive westward and south of Prince William Sound
through this afternoon and then onward/southward to Kodiak Island.
There is a Winter Weather Advisory out for northern Kodiak Island
for 3 to 6 inches of snow and blowing snow. Visibilities reduced
to one half mile or less at times. Looking towards the end of the
short term, the overall synoptic pattern will remain fairly
steady-state in nature. General 500 mb troughing for much of
Alaska and ridging over the Bering means Southcentral will stay
cold and mostly dry for the foreseeable future, with gap winds
continuing for favorable locations.

-AM

&&


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

The forecast remains unchanged with regards to the short-term
period. An exceptionally cold airmass continues to push in across
Southwest Alaska. In addition to cold temperatures, gusty
northerly winds will persist across Southwest through the rest of
the weekend and into next week. Strong winds in the Kuskokwim
Delta may loft snow on the ground from the previous weather event
from Kipnuk north and west and north and west of Bethel during the
weekend. Due to the threat of blowing snow, a Blizzard Warning is
in effect for the aforementioned regions. There is still some
uncertainty regarding the amount of transportable snow remaining
on the ground in those areas. Also, the very cold air will move
over considerably warmer ocean temperatures (30s), leading to
numerous snow showers over the Eastern Aleutians and the Alaska
Peninsula today and the rest of the Aleutians Sunday. This,
combined with strong winds could lead to blowing snow and low
visibility. A Winter Weather Advisory has been issued for the
Alaska Peninsula due to this potential for blowing snow. Another
threat with the cold and winds is wind chill. The Kuskokwim
regions could see wind chills 35F below zero for a period. Bristol
Bay will see wind chills from 20F to 30F below zero, especially
in the Dillingham region. A Wind Advisory as been issued for the
Dillingham area highlighting the gusty winds and wind chill threat
this weekend.

High pressure will set up over Southwest Alaska and most of the
Bering Sea/Aleutians early next week. This will keep the cold air
mass in place and set up drier conditions overall. Winds will
begin to slowly diminish through Monday as well. Some snow showers
may move across the Central Aleutians late Sunday night into
Monday morning as the Arctic trough responsible for the bitter
cold airmass moves into the North Pacific and interacts with a
North Pacific low south of the Chain. Models are hinting at the
next front/low combinations entering the Western Bering/Aleutians
Wednesday morning. The consensus as of now is for the front to
remain mostly confined to the Western Aleutians as the system
brings some rain across the area and some gale-force winds to the
marine areas of the Western Aleutians by late Tuesday night into
Wednesday morning.

&&


.LONG TERM FORECAST (Days 4 through 7: Wednesday through Saturday)...

The long-term pattern continues to favor mostly cold and windy
conditions across the Southern Mainland Wednesday through
Saturday. Across Southwest Alaska and the Alaska Peninsula
(AKPEN), a trough digs south over the Peninsula as a ridge builds
and amplifies northward through the Bering. As the trough crosses
the AKPEN Wednesday, northerly winds and wind gusts will be
enhanced in its wake as colder air advects in. Cold, windy, and
dry conditions also persist across Mainland through Saturday.
While the Central and Eastern Aleutians remain dry and under the
influence of ridging during the long-term period, the Western
Aleutians will be behind the ridge and under the influence of
warmer southerly to southeasterly winds. A series of weak fronts
may clip the Western Aleutians bringing light rain to the area
through the period, along with gale-froce winds across the marine
areas of the Western Aleutians. The pattern for Southcentral also
remains mostly the same with a series of Gulf lows lifting to the
central Gulf through the long-term which will help to pull winds
through the favored gaps and passes; especially Valdez Narrows,
Resurrection Bay, Passage Canal, and the Matanuska Valley.
Moisture from the Gulf lows looks to mainly be confined to the
northern Gulf Coast Wednesday and Thursday as the interior remains
cold, dry, and windy at times.

&&

.AVIATION...

PANC...VFR conditions along with strong northerly winds and gusts will
persist through Sunday. Wind speeds and gusts will likely diminish
slightly from their peaks (gusts to 40 to 55 mph) earlier today.
However, another round of winds and gusts of similar strength are
expected by mid-morning Sunday. The strong winds will likely
allow localized drifting and blowing snow to continue.

&&

$$

180
FXAK69 PAFG 062201
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
101 PM AKST Sat Dec 6 2025

.SYNOPSIS...
Cold and windy conditions continue across the Interior through
Sunday. Winds decrease rapidly Monday, but cold temperatures
remain. Mostly clear and dry weather expected through the week,
except for Monday and Tuesday along the North Slope where a weak
front brings some clouds and snow chances across the Arctic Coast.

&&

.KEY WEATHER MESSAGES...
Central and Eastern Interior...
- Areas of stratus clouds are diminishing in coverage, allowing
valley temperatures to drop into the 20s and 30s below zero with
a few 40F below zero readings.

- Cold and windy this weekend for most of the Interior.
- N/NE wind increases significantly Saturday from the Yukon
Flats southwest. Gusts above 1000ft may be upwards of 30 to 50
mph whereas valleys can see gusts up to 35 mph (WHEN the
inversion breaks). This continues into Sunday PM, then
weakens.
- Ambient temperatures through Sunday, with no clouds or wind,
between 20F to 40F below zero. A few colder spots, especially
north and east of Fairbanks may hit 45F below. Valley
temperatures may increase with winds, but wind chills of -40
to -60 are expected when these winds reach valley floors.
- Wind chill values of 40 to 60 below zero from Tanana to the
Yukon Flats this weekend. Significant blowing snow is expected
in the higher terrain above 1500ft. Periods of blizzard
conditions are expected along portions of the Steese/Dalton
Highway Summits and along the southern slopes of the AK Range.
- This could be a significant wind event and end up being
impactful as it could lead to tree damage and power outages.

- Colder and calm weather prevails next week with minimum
temperatures dropping between 30F and 50F below zero. A few
colder spots in the Yukon Tanana Uplands (like Chicken) may
approach 50F below zero.

West Coast and Western Interior...
- A cold trend continues through the weekend. Expect minimum
temperatures in the single digits above and below 0 along the
coast and in the teens to 30s below zero in the Interior
Valleys.

- North-northeast winds increase today. Wind gusts may be up to 30
to 40 mph along the coast from the Seward Peninsula south.

- Winter weather advisories have been issued for the Middle to
Lower Yukon Valleys and the Eastern Norton Sound for blowing
snow and dangerous wind chills. Gusts of 35 to 50 mph could lead
to periods of blowing snow and wind chills as low as 50F below
zero.

- Blizzard warnings for the Upper Kuskokwim and Western Alaska
Range have been downgraded to Winter Weather Advisories. The
snowpack was not as blowable as initially expected and prolonged
periods of blowing snow are no longer expected. Dangerous wind
chills remain a threat with wind gusts of 30 to 50 mph that
could lead to wind chills as low as 50F below zero.

- Winds weaken Monday and temperatures decrease again next week.
Lows potentially in the 30s/40s below zero in the Interior and
single digits/teens below zero along the coast.

North Slope and Brooks Range..
- Most of the light snow chances have ended. There is another
chance for light snow Monday night into Tuesday as a front
approaches. Up to 1 inch of snow is possible.

- Widespread temps in the 20s and 30s below zero with some 40F
below readings possible.

- Northerly winds increase today up to 10 to 15 mph along the
coast and up to 25 to 35 mph through Brooks Range passes. Wind
chills fall to as cold as -60F through the Brooks Range passes.

- Wind diminishes Sunday with a warming trend into the early part
of next week as clouds increase in coverage with chances for
snow.

&&

.FORECAST ANALYSIS AND DISCUSSION...
For Saturday through Tuesday.
At the start of the forecast period Saturday, a strong 553
decameter upper level high and a 501 decameter upper level low are
creating a very strong jet of winds aloft over the region. This
jet of strong winds is creating strong gusts near the surface
which, when combined with the very cold temperatures (-22C to -32C
at 850mb) is creating areas of dangerous wind chills. This
pattern is additionally very dry and has left most of the Interior
completely clear. Strong temperature inversions in the valleys
and the very stable and cold air within them is limiting the
strongest winds from completely reaching valley floors. Clear
conditions and very low sun angles encourages the formation of
strong inversions and winds threaten to mix out these inversions.
At higher elevations, gusty conditions prevail, but the ambient
temperatures aren`t quite as cold. Dangerous wind chills are still
a threat however, as well as the potential for areas of low
visibility due to blowing snow. This snow would be from the snow
seen earlier in the week across the Interior as we are too dry to
produce any new snow where the strongest winds are.

This windy pattern lasts through Sunday, although slowly weakens
as the high and low even out slightly. Sunday night through
Monday winds decrease rapidly bringing the region to mostly calm
conditions by late Monday. The wind chill threat will end, but
ambient temperatures in Interior Valleys will once again decrease
into the -30F to -45F range with the coldest spots potentially
reaching as low as -55F. Clearer and calmer conditions persist
through most of the region through Friday, except for the North
Slope where a weak shortwave feature rotating through the
weakening high and low pattern will pass over the area Monday into
Tuesday bringing clouds and the chance for light snow.

&&

.EXTENDED FORECAST DAYS 4-7...
For Tuesday night through next Saturday.
At the start of the extended forecast period Tuesday night, a
strong ridging pattern extends over the Bering Sea and weak
troughing sits over the Eastern portion of the state. This ridge
acts as a shield for the Interior deflecting lows attempting to
move into the region to the south or north. Model agreement is low
on exactly how each weaker low pressure system moves as it
interacts with the higher pressure ridge, but this feature will
likely keep the region below our normal temperatures through the
end of next week. There is however a chance that a strong enough
low could try and move over the top of the ridge pattern and
actually make it into Northern Alaska. Should this happen it could
push out the cold air that has settled over the region and lead to
a period of warmer, cloudier conditions with chances of snow.
Otherwise cold and dry conditions will dominate the state through
the end of next week.

Coastal Hazard Potential Days 3 and 4...None


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Cold Weather Advisory for AKZ809>811.
Blizzard Warning for AKZ848-850.
Winter Weather Advisory for AKZ824-829-830-851-852.
Blizzard Warning for AKZ832-834.
Cold Weather Advisory for AKZ833-838>847.
PK...Gale Warning for PKZ801-802.
Brisk Wind Advisory for PKZ803-804.
Gale Warning for PKZ805-852.
Brisk Wind Advisory for PKZ816-817.
Gale Warning for PKZ850.
Heavy Freezing Spray Warning for PKZ851.
Small Craft Advisory for PKZ851.
Brisk Wind Advisory for PKZ853.
Brisk Wind Advisory for PKZ854.
&&

$$

Stokes

281
FXAK67 PAJK 070654
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
954 PM AKST Sat Dec 6 2025

.UPDATE....Evening and 06z Aviation Update...
Snow continues across the northern panhandle with rain continuing
over the central and southern panhandle. Over the northern
panhandle, moderate snow rates continue with the exception of
Yakutat and Skagway where rates have begun to slightly diminish.
Snow over Yakutat has slightly diminished due to precipitation
ending, but is continuing to see some times snow and reduced
visibilities. The Winter Weather Advisory has been allowed to
expire with these diminishing rates. Snow rates over Skagway have
decreased due to continued northerly wind bringing dry air into
the area. Although, there is another band of moisture pushing
northward into the area. We will continue to monitor the central
and southern panhandle as temperatures decrease allowing for
wintry mix and snow to begin.

&&

.SYNOPSIS...

Key Messages:

- Moderate to heavy snow continues over the northern panhandle
and will continue to spread southward into central and southern
panhandle as temperatures decrease.

- Cold temperatures moving into SEAK to start the week, with some
areas seeing single digits or sub zero temperatures. Apparent
temperature along White pass dipping below -20. This weekend
through next week, models continue falling into line behind a
weather pattern that has been known to produce heavy snow.
Higher confidence in totals for the northern panhandle, but
still some uncertainty remains about timing and amounts as cold
air pushes southward.

&&

.SHORT TERM.../Tonight through Monday/...A front continues moving
across the panhandle tonight, followed by multiple waves of
precipitation that will continue to move across the panhandle
throughout the rest of the weekend. Throughout the night and
morning, the arctic boundary in place has continued to push
southward quicker than initially expected following cold and dry
northerly air pushing into the northern panhandle. This trend is
expected to continue throughout the weekend, with the arctic
boundary progressively moving southward tonight and tomorrow,
moving forward the anticipated snowfall across the central
panhandle a day sooner than was expected yesterday due to the path
of the low and northerly winds pushing in faster. The boundary
should continue to slide southward and linger over Icy Strait
Corridor tonight into tomorrow as the next wave of precipitation
moves through, bringing another round of heavy snow to Juneau and
Gustavus, and allowing for colder air to move in and bring heavier
snow to Hoonah, Elfin Cove and Pelican as well. Juneau should see
additional snow accumulations of 12 to 16 inches in the next 24
hours, with the heaviest rates of 1 inch per hour being possible
early in the morning Sunday through the morning hours as the wave
of heavier precipitation moves through. Gustavus should also see
additional accumulations of 10 to 12 inches through tomorrow
afternoon. When the rest of Icy Strait Corridor sees the cold air
moving in by tonight, areas near Hoonah, Elfin Cove, and Pelican
will see more snow accumulation that will last into tomorrow
night, with between 10 and 14 inches in 24 hours expected over
Hoonah and Eastern Chichagof Island and 8 to 10 inches for the NE
Gulf Coast and Cross Sound area.

As the arctic boundary continues to move southward tomorrow into
Monday to around the central panhandle, bringing in some mixing and
snowfall. Snow mixing is expected into tomorrow for Sitka, Angoon,
Kake, and Petersburg, and becoming snow by tomorrow night. While
there will be some accumulation of less than 2 inches from Angoon
and Sitka down to Wrangell possible tomorrow, the higher snowfall
amounts and rates are not expected for the Petersburg and Wrangell
areas until Monday as the colder air and subsequent higher snow
ratios set in, alongside the next front moving through the southern
panhandle, bringing an expected 8 to 10 inches in 24 hours Monday.

Tonight the far northern panhandle will begin to see a diminishing
trend in precipitation amounts, but will still see an additional 9
to 13 inches in the next 24 hours, with the higher end of snow
accumulation being expected in Haines and along the Haines Highway.
This snow will be a lot lighter in density, and alongside the up to
40 to 50 mph gusts down parts of the Klondike Highway and Chilkat
Peninsula, some potential for blowing snow may impact areas that see
gusty winds during the heavier snow rates tonight into tomorrow.
Yakutat will also see a diminishing trend in precipitation, with the
northern panhandle not being expected to see enough moisture to see
any real snow accumulations Monday, rather staying cold and dry from
the northerly outflow keeping the next system from pushing any real
precipitation in. Instead this next system will largely impact the
southern panhandle, which will begin to see some cooler temperatures
beginning tomorrow night into Monday morning, enough for snow to mix
in and possible accumulation down to PoW and Ketchikan if the
temperatures decrease enough for accumulation from the mixing.

.LONG TERM.../Monday night through Saturday/ Arctic boundary
continues to move southward over the southern panhandle at the
start of the mid range and will likely move south of the panhandle
by mid week. Building high pressure in NW Canada and Alaska
Interior is creating offshore flow and ushering colder air through
the northern panhandle. This air is very cold with 850 mb temps
plummeting into the -15 to -25 C range by mid week across the
northern panhandle and near -10 C over the south. At sea level
this is translating to overnight lows reaching single digits above
or below zero for the north and teens and 20s for the south.
Daytime highs will struggle to get into the 20s for the north and
into the 30s for the south. Coldest temperatures look to occur
Monday night into Wednesday night, but sub freezing temperatures
are likely to stick around into next weekend as well. Northern
panhandle will be watched as many locations will be approaching
their criteria for cold weather advisories or extreme cold
warnings (especially the haines and Klondike Highways) early to
mid week.

In addition to the cold, strong outflow winds are also expected
with many northern panhandle channels seeing gale force outflow
through most of the week. A strong 1035 mb high in the Yukon is
the main driver of that outflow and it will just persist and
strengthen to 1045 mb by late next week. Expect gusty winds out of
many of the outflow areas in the northern panhandle to start
with, but expect outflow out of areas farther south through the
week as the Yukon high spreads into northern British Columbia by
late week. With these winds and the cold air that it is bringing,
a few secondary effects will be noticeable. First, wind chills
will be rather frigid reaching into the negative teens and
possibly colder in the north most of the week. Second, is that
freezing spray will become a more widespread problem for many
marine areas in the inner channels and along the NE gulf coast.
The freezing spray could become heavy at times in Lynn Canal, Near
Taku Inlet, and northern parts of Glacier Bay throughout the
week.

Otherwise, most of the panhandle will be dry through the mid and
long range except for possibly the south. A series of lows will be
moving into the BC coast and could send some of their precip into
the southern panhandle throughout the week. Given how cold the
atmosphere is expected to be the precip, when it does fall, will
mostly be in the form of snow. Highest accumulations possible
early Tuesday, but additional accumulations will likely be low for
the mid week period. There is the possibility of a another snow
event for the south next Friday into Saturday with a couple inches
of accumulation possible but storm track is uncertain at this time
for that system.

&&

.AVIATION...Predominately IFR flying conditions continue north of
Juneau as snow continues across the area. This snow is mainly
bringing reduced visibilities to below 2 SM and times of
visibilities AoB 1/2 SM. Ceilings across the panhandle remain
around 1500 to 2500ft as precipitation continues across the area.
Areas around Yakutat and Skagway will be the first places to see
improving conditions as precipitation diminishes.

Otherwise, the central and southern panhandle will continue to see
MVFR conditions due moderate to heavy rain over the area. The
rain/snow line will continue to move south tonight into Sunday
eventually bringing a wintry mix and snow to the central and
southern panhandle. As these areas start to see snow, visibilities
will quickly be reduced to below 2 SM.

Along with this precipitation, winds have begun to increase and will
continue to increase, especially for the northern panhandle. By late
Sunday morning, Skagway will begin to see sustained winds around 30
kts with gusts up to 45 kts. Elsewhere, winds becoming 10 to 15 kts
with gusts 20 to 25 kts. These stronger winds continue well into
next week with strong northerly outflow.

&&

.MARINE...
Outside (Gulf and Coastal Waters): A low pressure continues to sit
in the western Gulf this afternoon bringing southerly fresh to
strong breezes to the outer coast and offshore waters. These
conditions are expected to persist while near gale to gales are
expected to develop for those areas that are favored by outflow
winds. In particular, near Cape Spencer and Yakutat Bay could see
near gales to gales. As the low remains over the western Gulf, winds
will continue but could see some slowing for areas south of Cape
Edgecumbe with speeds around fresh to strong breezes. To the north,
the near gales to gales continue going into Monday and Tuesday for
the outflow winds. With the low remaining in the Gulf, wave heights
are expected to remain elevated with 10-15 ft seas and a SW swell
component.

Inside (Inner Channels): The Arctic boundary continues to push
southward this afternoon with the boundary around Taku Inlet for the
Stephens Passage area and somewhere between Point Couverden and
Tenakee Springs. As the boundary continues its trek southward, winds
will continue to shift to north while wind speeds are expected to
increase for the Lynn Canal area. To the south, winds are expected
to remain out of the south before switching to either more of a
northerly or easterly wind as the pressure gradient increases.
Headed into the start of the week, a low is expected to move across
the southern panhandle which should allow for winds to diminish for
the southern Inner Channels. Meanwhile, winds and cold temperatures
across the northern Inner Channels will likely see an increasing
potential for freezing spray, especially as the air temperature
continues to drop with the Arctic air mass.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Strong Wind until 6 AM AKST Sunday for AKZ317.
Winter Storm Warning until 3 PM AKST Sunday for AKZ318-319.
Cold Weather Advisory from 3 PM Sunday to 6 PM AKST Monday for
AKZ318.
Extreme Cold Watch from Monday evening through Tuesday afternoon
for AKZ318.
Winter Storm Warning until midnight AKST Sunday night for AKZ320-
321-325.
Winter Weather Advisory until midnight AKST Sunday night for
AKZ322.
Winter Storm Watch from Monday afternoon through late Monday
night for AKZ326-329.
Winter Weather Advisory from 5 PM Sunday to 6 AM AKST Monday for
AKZ327.
Winter Storm Warning from 7 AM Sunday to 9 PM AKST Monday for
AKZ331.
MARINE...Gale Warning for PKZ011-012-053-644-651-652-664-671-672.
Small Craft Advisory for PKZ013-021-022-031>036-641>643-661>663.

&&

$$

UPDATE...EAB
SHORT TERM...Contino
LONG TERM...EAL
AVIATION...EAB
MARINE...SF

Visit us at http://www.weather.gov/Juneau