Graphical Hydro Meteorological Discussion

110
FXAK68 PAFC 040247
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
547 PM AKST Wed Dec 3 2025

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

Key Points:

* Transitioning from a warmer, freezing rain weather pattern to a
snowier, colder one.

* Southern Copper River Basin will likely see several days of
light snow from late this week into the weekend, leading to
overall accumulations on the order of 6-12 inches.

* By Friday, increasing offshore winds will lead to frigid wind
chills (especially near the Alaska Range) and the potential for
blowing snow.

Discussion:

The Winter Weather Advisories for freezing rain in Northwest Kenai
Peninsula and Anchorage/Eagle River have since expired as
precipitation has tapered off. One thing to watch for will be the
potential for another brief period of freezing rain along Central
Kenai Peninsula tomorrow morning, before the influx of colder air
changes precipitation over to snow.

Otherwise, we`ll be turning the corner from near-freezing
temperatures and freezing rain, to drier and more frigid
conditions. One forecast challenge will be how much snow we`ll see
tomorrow, before the much drier and colder air moves in. A robust
upper-level shortwave moving into the north Gulf coast could
bring light accumulations to parts of Kenai Peninsula, Anchorage,
and Matanuska Valley, with higher amounts along Prince William
Sound and the Copper River Basin. This is what`s represented in
the forecast. However, the NAM has been stubbornly holding onto a
much drier solution, with little snow expected for tomorrow. This
model solution remains the outlier, but it hints at the potential
for a much drier scenario than currently forecast.

Looking ahead to Friday, a low pressure system moving across the
Gulf towards Southcentral Alaska will tighten surface pressure
gradients and bring another round of snow to Prince William Sound
and Southern Copper River Basin. Forecast confidence is high that
temperatures will be very cold, with minimum temperatures dropping
into the teens and single digits by Friday night, with even colder
temperatures on the way this weekend. While this type of synoptic
weather pattern favors gusty outflow winds, forecast confidence
is a bit lower with the timing and strength of these winds, as
these aspects of the forecast are more reliant on the track of the
low. Depending on the eventual low track and wind speeds, we
could see wind chills dropping into the single digit negatives for
most of the Southcentral Mainland, with wind chills as low as -30
to -40 in the deep interior. An additional hazard will be the
potential for blowing snow and perhaps even blizzard conditions,
which will also depend on the low track and where snow falls
before or during the strongest winds. Overall, even though we`ll
be moving out of our yucky freezing rain pattern, there remain
cold weather hazards on the horizon to watch out for, so stay
tuned to the forecast.

-Chen

&&


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

The low over the Aleutians continues to weaken which is allowing
for freezing rain and snow chances to start reducing. However, due
to the continued threat of blowing snow along the Kuskokwim Delta
Coast and freezing rain showers from Bethel South, a Winter
Weather Advisory has been issued. Also, snow and gusty winds
continue in the Pribilof Islands, so a Winter Weather Advisory has
been issued for snow and blowing snow. This impactful weather in
Southwest Alaska should taper off by tomorrow as the low continues
to weaken. By Thursday afternoon, lingering showers will affect
Bristol Bay.

Next up is an Arctic airmass pushing into Southwest Alaska from
the north. Temperatures will plummet into the weekend as an Arctic
trough dives into the region. Temperatures will drop below zero
across the Kuskokwim Delta and the Lower Kuskokwim Valley by
Friday night. Another effect of the Arctic trough will be an area
of gusty north to northeasterly winds off of the Kuskokwim Delta.
These winds will reach gale to storm force in strength and will
stretch all the way down to the Aleutians. Stronger gap winds in
the Aleutians are likely with these winds. A consequence of these
offshore winds is the threat of extreme freezing spray from
Nunivak Island to Cape Newenham. A Marine Weather Statement has
been issued for Saturday through Tuesday detailing this threat.
Another consequence of the gusty winds and very cold temperatures
is wind chill. Wind chills could dip below 35F in the Kuskokwim
Delta by Saturday night into Sunday. Looking ahead, it seems like
the Arctic air mass will persist into next week, potentially
allowing for a long period of extremely cold temperatures.

-JAR

&&


.LONG TERM FORECAST (Days 4 through 7 - Sunday through Wednesday)...

A broad area of low pressure will fill most of the Gulf of Alaska
on Sunday and remain in place through next week. Forecast models
have various differences on when low pressure breaks down and
moves out of the Gulf. To the west, high pressure will persist
over the Bering while a weaker front systems track south of the
Aleutians. As has been advertised, beginning on Friday a
significant outbreak of colder air is forecast to spill out of
Canada and into interior Alaska, eventually reaching the eastern
Bering and Alaska Peninsula on Sunday. Cold temperatures are
expected to remain in place through early next week, with cold air
over the Alaska Peninsula to wrap back into the Gulf of Alaska
Sunday into Wednesday. Strong winds out of the interior are
forecast and there is potential for high winds into Southwest
Alaska. The strong northeasterly flow of colder temperatures atop
warmer Bering Sea waters will also promote ocean effect snow
showers for parts of the Aleutian Chain and Alaska Peninsula.
Meanwhile, the denser cold air over Southcentral will increase gap
winds through the usual locations and into the Gulf of Alaska.
With the colder temperatures, areas of snow will be possible for
numerous locations, but nailing down the when and where will
require further analysis of newer model data. The BLUF, it`s going
to be colder; there will be wind through the gaps; and snow
chances will continue to increase through the middle of next week.
Stay tuned.

-BL

&&
.AVIATION...

PANC...VFR conditions will give way to MVFR ceilings this
evening. Flow then weakens further overnight with IFR and LIFR
conditions possible with fog formation. Fog formation will depend
on if there is any clearing early this evening when radiational
cooling can be maximized with shallow dewpoint depressions.

Looking ahead to Thursday, there is uncertainty regarding the
track of a surface low. A more northern track with this system
into Prince William Sound would yield more snow over the terminal
with MVFR to IFR conditions. Conversely, a more south and east low
track would yield less in the way of snow and better chances for
VFR conditions.

&&


$$

829
FXAK69 PAFG 032327
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
227 PM AKST Wed Dec 3 2025

.SYNOPSIS...Snow is rapidly ending across Northern Alaska this
afternoon as a strong cold front pushes from northwest to
southeast. High pressure setting in behind the cold front will
bring a prolonged period of windy and very cold conditions. Winter
Storm Watches for cold wind chills, strong winds, and blowing snow
are in effect for much of the CWA to cover impactful weather
expected over the weekend and into next week. Winds are likely to
mix all the way down to interior valley floors at times as well.

&&

.KEY WEATHER MESSAGES...
Central and Eastern Interior...
- Skies continue to clear rapidly this afternoon and evening.
Patchy fog is possible as skies clear, but will be short lived.

- Temperatures drop dramatically tonight and tomorrow with all
locations below zero by Thursday morning.

- Strong northeast winds increase as a very cold airmass sets up
Thursday well into next week.
- In terms of wind, locations over 1000ft may gust upwards of 25
to 50 mph. Interior valleys (including Fairbanks) have a chance
to see wind gusts up to 30 mph IF the inversion breaks Saturday
through Monday.
- This could be a significant wind event and end up being
impactful as it could lead to tree damage and power outages.
- Blizzard conditions are possible Friday and Saturday along the
Parks Highway from Carlo Creek to Cantwell and from Trims Camp to
Fielding Lake along the Richardson Highway.
- Wind chills reaching -40 F to -60 F are very possible Saturday
and Sunday across much of the Interior. Valleys west of
Fairbanks are more likely to see wind mix out inversions.

- A cold trend continues through this weekend well into next week.
Under clear skies and in areas with no wind, temperatures are
likely to drop to -30F to -45F (potentially -50F in the coldest
spots).

- Any clouds will limit how cold it gets and the highest chances
for clouds will be in the Southeast Interior/Upper Tanana
Valley.

- Winter Storm Watches have been issued for strong winds, blowing
snow, and very cold wind chills for the Yukon Flats, Dalton
Highway Summits, White Mountains, and for southwest of
Allakaket.

West Coast and Western Interior...

- A cold trend continues through the weekend. Expect minimum
temperatures around or slightly below 0 along the coast and in
the teens to 30s below zero in the Interior Valleys.

- North-northeast winds increase this weekend and if these winds
can break through the inverted valleys, it will bump up
temperatures slightly, but wind chills would still be very cold.
East wind gusts may be up to 35 to 45 mph along the coast and
in the higher terrain.

- With temperatures below 0 and wind this strong, it could lead
to wind chills as low as -50F in some spots.

- Winter Storm Watches have been issued for strong winds, blowing
snow, and very cold wind chills from Koyuk to Huslia and south
to the Yukon Delta from Friday night through Monday night.

North Slope and Brooks Range...

- A front moves from the Western Arctic Coast to the Eastern
Arctic Coast between Thursday to Friday with areas of light snow
along the coast. Persistent onshore flow follows afterwards with
much colder temperatures this weekend.

- Expect temps in the negative teens along the coast with -20s
inland through Thursday night, then widespread temps near the -30s
with some -40F readings possible in the coldest locations this
weekend.

- High pressure persists well into next week with dry and very
cold conditions, as well as northerly winds and wind chills as
cold as -60 F through Brooks Range Passes.

&&

.FORECAST ANALYSIS AND DISCUSSION...As of 1215pm Wednesday, a band
of light to moderate snow stretches from Nikolai to Lake
Minchumina to Nenana to the White Mountains and southeast to the
Alaska Range to Salcha to Circle Hot Springs. This band will
continue to move southeast through tonight with skies clearing
rapidly behind it as snow ends. Patchy fog is possible as clearing
happens, though it should be short lived due to just how rapidly
temperatures will cool. By Thursday morning, many Interior
valleys will be in the 20s below zero, a swing of around 40
degrees in 24 hours. By Saturday morning, the upper level pattern
will feature a closed high over the Chukotsk Peninsula along with
a low over Cook Inlet. This is historically a cold and very
persistent pattern for northern Alaska. The cold and increasingly
windy conditions look to last for over a week. Across the West
Coast, high pressure continues to build with cold and dry
conditions likely to continue well into next week or longer. Winds
will increase mainly southwest of the Seward Peninsula as
multiple low pressure systems move into the Gulf of Alaska,
tightening the surface gradient. For the North Slope, an upper
level low moving south out of the Beaufort Sea will bring clouds
and light snow for Thursday and Friday, but otherwise conditions
will be dry and cold with mainly light winds.

&&

.EXTENDED FORECAST DAYS 4-7...Monday through next Thursday.
High pressure over the Bering Strait with a low in the eastern
Gulf of Alaska looks to continue through next week. This will
bring prolonged cold to Northern Alaska. Winds look to diminish in
the Tuesday-Wednesday timeframe as the gradient eases. This will
allow for valley inversions to strengthen, and with 850 mb
temperatures -20 C or colder, conditions may support temperatures
in the -40s or 50s.

Coastal Hazard Potential Days 3 and 4...None

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Winter Storm Watch for AKZ848-850.
Winter Storm Watch for AKZ824>826-828>830-832>834-846-847-851-
852.
PK...Gale Warning for PKZ801-850.
Brisk Wind Advisory for PKZ802.
Brisk Wind Advisory for PKZ803>805-852.
Small Craft Advisory for PKZ806.
Heavy Freezing Spray Warning for PKZ806-817-854.
Brisk Wind Advisory for PKZ815-861.
Small Craft Advisory for PKZ816-853.
Heavy Freezing Spray Warning for PKZ816-851.
Small Craft Advisory for PKZ817-854.
Heavy Freezing Spray Warning for PKZ850.
Small Craft Advisory for PKZ851.
Heavy Freezing Spray Warning for PKZ853.
&&

$$

Chriest

227
FXAK67 PAJK 040652 AAA
AFDAJK

Southeast Alaska Forecast Discussion...UPDATED
National Weather Service Juneau AK
952 PM AKST Wed Dec 3 2025

.Evening and 06z Aviation Update...
Made a few adjustments to the near term in the northern
panhandle. Drier, drainage flow has decoupled winds in Haines and
Skagway, resulting in light to westerly or northerly respectively.
Not expecting any change going forward, as the drainage flow is
expected to keep stable air flowing into the area, keeping the
stronger southerlies of northern Lynn Canal from mixing down to
the surface. Otherwise, made several adjustments to wind
directions over communities to match current observations, as
conditions are not expected to drastically change in the next 6-12
hours.

&&

.AVIATION.../through Thursday evening/
A wide variety of flight conditions this evening as onshore flow
keeps low clouds and isolated showers across the panhandle.
Looking at obs around the area, TAF sites range from isolated
pockets of VFR & LIFR to predominate and widespread MVFR & IFR
with CIGS AoB 3500ft and visbys between 3 to 6SM within rain and
mist. Through Wednesday night flight conditions will overall
continue to worsen, generally bouncing between MVFR to LIFR flight
conditions with CIGS AoB 2500ft and visbys around 2 to 4SM by 15z
Thursday morning across the panhandle, with low ceilings
persisting and visbys slow improving through Thursday afternoon.
Winds should remain around 10 kts or less overnight, going near
calm and variable by 12z, increasing once more into Thursday
afternoon to around 5 to 10kts. No LLWS concerns through the TAF
period.

.PREV DISCUSSION......ISSUED AT 427 PM AKST Wed Dec 3 2025...

SYNOPSIS...

Key Messages:

- An exiting front brought mainly rain to the panhandle today.
Lingering rain will diminish tonight and tomorrow.

- Onshore flow will keep the warmer-than-normal temps in place
through Thursday. Colder weather begins to slide south into the
area Friday night.

- Late this week into next weekend, long range models are still
hinting at a weather pattern that has been known to produce
heavy snow. High uncertainty at this time but worth watching
closely

&&

.SHORT TERM.../through Thursday night/...

The exiting front from today brought rain and brief elevated
winds. But as it moves out, wind speeds will continue to decrease
with the lingering rain diminishing.

Going into Thursday, continued onshore flow will keep the rainy
and cloudy weather in place with continued warmer-than-normal
temperatures.

Overall, a quiet short term when compared to the pattern change
coming this weekend.

.LONG TERM.../Friday through Monday/...A pattern change going
into this weekend is looking to bring cold temperatures, heavy
precipitation, and strong winds to the panhandle into early next
week.

A system advancing into the northern gulf through Friday will
send a front into the panhandle overnight Friday before stalling
in the northern gulf through the weekend, funneling consistent
moisture over the panhandle. This front will bring moderate to
heavy rain rates to the area, with around an inch expected for a
majority of locations and persisting at similar rates through the
weekend. A cold air mass aloft shifts into the Yukon and continues
to moves southward through the weekend. A tightening pressure
gradient over the northern panhandle will increase outflow winds
through the weekend, helping to funnel the colder air south into
the panhandle. Decreasing temperatures with ample available
moisture will increase the potential for heavy snowfall in the
northern panhandle, extending south through the weekend and into
next week. Highest confidence of snowfall remains across the far N
Panhandle and a Winter Storm Watch has been issued for Haines and
Skagway starting Friday night, continuing through Saturday.
Looking elsewhere, Yakutat will also see higher amounts of snow,
but currently expecting just below warning levels. Forecast
becomes more of a challenge moving towards the Icy Strait
Corridor, starting as rain and transitioning into a mix by
Saturday, limiting potential amounts initially. Snow level drop
south following the colder temperatures, snow potential will also
move further south towards the corridor, and the rain/snow mix
will then follow into the central panhandle. Stay tuned to the
forecast moving into the weekend as details come into clearer view
regarding potential amounts and refined timing for the Icy Strait
Corridor and Yakutat.

As the gale force low moves into the northern Gulf and a high
sets up to the north of the panhandle into this weekend, northerly
flow begins to set up over the northern panhandle into Lynn
Canal. This cold air mass to the north contributes to the colder
temperature trend over the weekend and into early next week,
alongside bringing stronger winds down Lynn Canal. These winds
will begin to increase Saturday into Sunday with northerly gales
in northern Lynn Canal with 35 to 40 kt winds by Sunday afternoon
as the gradient tightens over the northern panhandle. Winds will
increase in Skagway at this time, however the stronger sustained
winds will likely stay below 30 mph, with the northerly wind not
being expected to be strong enough to dry out the air too much
enough to reduce the snowfall amounts. Other land areas will see
an increase in SE winds as the front moves through, with
diminished winds between the waves of precipitation that push
through this weekend into early next week.

&&

.MARINE...Outside Waters: A front is exiting the area this afternoon.
Behind this front wind speeds have been decreasing. And these
winds will continue their downward trend tonight and into Thursday
as ridging passes over the Gulf waters. Seas will lower to
between 7 and 9 ft for Thursday. Winds and seas look to rise
Thursday night into Friday, especially from Cape Edgecombe south,
as a low will track east through the southern Gulf and towards
Haida Gwaii. For the weekend, a forecasted low near the northern
Gulf will give the eastern Gulf waters 25 to 30 kts with areas of
35 kts. These elevated winds will last into next week.

Inside waters:
A front is exiting the area this afternoon. Winds will continue to
diminish behind the front with lighter onshore flow setting up.
Winds continue this diminishing trend across the inner channels
into Thursday as ridging sets up in the Gulf. Then, winds are
expected to begin to increase Thursday night into Friday with a
system passing to the south of the southern panhandle, with brief
northerly/easterly outflow developing to the north. Southerly
winds return by Friday morning but Friday night, northerly flow
returns to Lynn Canal. Speeds in the inner channels pick up to 20
to 25 kts by Friday night with the weekend seeing 25 to 35 kts.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Storm Watch from late Friday night through late Saturday
night for AKZ318-319.
MARINE...Small Craft Advisory for PKZ022-053-641>644-651-652-661>664-671-
672.

&&

$$
UPDATE...NC
SHORT TERM...GJS
LONG TERM...ZTK
AVIATION...NM
MARINE...GJS

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