Graphical Hydro Meteorological Discussion

751
FXAK68 PAFC 100126
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
426 PM AKST Tue Dec 9 2025

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

Winds have calmed down across Southcentral Alaska including in the
Matanuska Valley as weak ridging builds into the region. Due to
the lower winds and another push of cold air from the north,
low temperatures have cooled into the negatives and single digits
across Anchorage, the Mat-Su Valley, and the Kenai Peninsula. The
Copper River Basin including Glennallen to McCarthy are seeing
overnight temperatures of -40F and below. Thompson Pass is still
seeing gusty winds and wind chills to -40F. Due to these very cold
conditions, the Cold Weather Advisory has been extended until 4 PM
Friday and now includes Thompson Pass.

On Wednesday, a weaker upper trough moves into Southcentral. This
will cause winds speeds to increase in gap areas including Valdez
and around Kodiak Island. The Matanuska Valley will see increased
winds as well, but these will not nearly be as strong, lengthy,
nor widespread as the previous event. Anchorage and the Kenai
Peninsula will likely remain mostly calm through this upper level
trough. These effects will last through Thursday morning. The rest
of Thursday looks relatively calm wind-wise. Temperatures will
remain very cold as the Arctic air mass remains in place.

On Friday, a stronger upper trough pushes into Southcentral. There
is some uncertainty in the exact track of this trough and
therefore, impacts, but it will crank up winds speeds throughout
Southcentral. The Matanuska Valley could see gusty winds with this
trough. The Valdez gaps including Valdez itself is another area
that could see gusty winds. Cloud cover will likely increase with
this event, so temperatures across the area could be warmer,
especially in the Copper River Basin. However, another push of
cold air will arrive Saturday, further complicating things. Monitor
the forecast for more details as details of this event become
more clear.

-JAR

&&


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

A blocking ridge remains firmly entrenched over the Bering Sea,
maintaining dry and cold conditions over Southwest Alaska and
the eastern Bering Sea. Satellite imagery does show a short-wave
trough over the central Bering caught between two spokes of the
ridge. However, there is nothing more than some high clouds with
this. A second short-wave is rounding the top of the ridge,
digging southward across western AK. This will also come through
with nothing more than some high clouds. However, the Bering ridge
will amplify tonight through Wednesday, forcing this trough and
a reinforcing shot of Arctic air southward across Southwest AK and
the Alaska Peninsula. This will lead to a period of strong and
gusty northerly winds, especially through bays and passes along
the Alaska peninsula during the day Wednesday. The ridge will then
quickly build eastward toward Southwest AK Wednesday, leading to
diminishing winds and falling temperatures.

Meanwhile, storm systems tracking to the west of the upper level
ridge will bring southerly winds and periods of rain to the far
western Aleutian Islands, including Shemya. One storm will flatten
the ridge as it tracks into the Arctic on Thursday. While most of
this will head eastward across northern AK, a trailing cold front
and weak short-wave will move into Southwest AK Thursday night
through Friday, likely bringing areas of light snow. There might
be just enough warm air moving off the Bering to produce rain or
freezing rain for portions of the Kuskokwim Delta coast, but
confidence in this is low. In any case, precipitation should be
brief and light. Cold air advection will bring another round of
winds Friday and into the weekend for portions of Southwest AK
and the Alaska Peninsula.

-SEB

&&


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

This weekend, an expansive area of high pressure, stronger than
1040 mb at the surface, will be centered over the northern Bering
Sea and extend across Western/Interior Alaska and much of the rest
of the Bering Sea. This high pressure will aid in pushing Arctic
Air south across the state, causing a trough to dig across the
southern mainland into the Gulf of Alaska. This will bring similar
conditions to last weekend, with potential for another round of
high winds out of gaps and mountain passes, along with continued
cold temperatures and wind chills. A developing complex surface
low in the Gulf of Alaska could retrograde just enough early next
week to bring some light snow to the north Gulf coast and parts of
the Copper River Basin, but forecast confidence is low at this
time. Otherwise, the entire forecast area is expected to remain
dry, and this could continue to be the case for the next several
weeks as this general pattern of cold, dry weather looks to stick
around.

Quesada

&&

.AVIATION...

PANC...VFR conditions and light northerly winds will persist.
North winds between 10 and 15 kt will develop Wednesday afternoon
as a trough moves into the Gulf.

&&


$$

683
FXAK69 PAFG 100051
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
351 PM AKST Tue Dec 9 2025

.SYNOPSIS...
Cold weather continues across Interior Alaska, and especially for
the eastern half and within the Yukon Flats and Upper Tanana Valley,
with values dropping below -50F for a few locations this morning,
such as Chicken at -56F. Due to gusty winds up to around 40 to 45
mph and very cold temps, dangerously low wind chills will be felt
for locations along the Yukon riverbed to the AlCan border, such as
Eagle, a Cold Weather Advisory has been issued through tomorrow
morning for Forty Mile Country. The North Slope by contrast is
relatively warmer for today, with temperatures in the single digits
and teens above zero as a round of light snow shifts eastward across
the area through tomorrow morning. Thereafter, colder air moves in
behind a cold front, dropping much of the North Slope into the
negative teens for tomorrow. This will quickly change from Thursday
through the weekend as a low from Siberia transitions over the state
from west to east, bringing widespread snowfall of at least an inch,
and much warmer temperatures to Alaska north of the AK Range. The
colder air locked in place across much of the Interior will begin to
scatter out with southerly flow and warming temperatures ahead of
the approaching low pressure system for Thursday into Friday. On the
North Slope, winds will increase today, which could result in
blowing snow and reduced visibilities at times, especially where
they combine with falling snow. Very cold conditions settling in
over the region into early next week could drop temperatures into
the -40s or -50s in much of Eastern Alaska, even outside typical
cold spots.

&&

.KEY WEATHER MESSAGES...
Central and Eastern Interior...
- Cold weather will continue across the Interior through
tomorrow, and then begins to warm on Thursday into Friday. Cold
valley locations will see lows in the -30s and -40s, with the
Upper Tanana Valley falling to around -50F.

- Beginning on Thursday, another system will move into the area
and yield snow totals widely of around 1 to 3 inches through the
weekend, with higher totals of over 4 inches possible from the
north slopes of the Western AK Range to the White Mountains.

- Considerably warmer temperatures are likely on Friday with this
system, with highs widely rising into the positive single or
double digits.

- Much colder air is going to settle back into the area,
especially over the eastern half of the Interior, during the
early part of next week, which may allow for even colder
temperatures to be possible.

West Coast and Western Interior...
- Cold weather with lows in the negative teens and 20s will
continue through tomorrow night ahead of the next system.

- From Thursday through the weekend, much warmer temperatures are
expected, with increasing clouds and generally around 1-4
inches of light snow.

North Slope and Brooks Range...
- Light snow will continue across the eastern North Slope through
tomorrow before colder air is ushered in by a cold front in its
wake. Accumulations will generally be light.

- A more robust wave of snow is expected from Thursday into the
weekend as a low moves along the Arctic coast. 2 to 4 inches of
snow are widely possible across the area. Higher totals are
possible in the Brooks Range and Arctic plains, mostly east of
the Dalton Highway. Portions of the eastern Brooks Range
southeast of Sagwon may also receive between 6-8 inches of snow.

- As the low moves along the coast, widespread winds of 25 to 35
mph, with higher gusts, will shift from SW to W and could
combine with falling/fresh snow to blow and reduce visibilities.

&&

.FORECAST ANALYSIS AND DISCUSSION...
Currently, a weak shortwave is transitioning across the North slope
and providing some light snow showers. There is also an area of high
pressure located over western Canada and a decaying wave with an
associated area of low pressure over the Gulf of Alaska has allowed
for the pressure gradient to tighten through the Yukon River and
Tanana River Valleys with a low-level jet present this morning,
which has been providing some strong and gusty winds for locations
from Delta Junction and Eagle. Because of the strong and gusty winds
up to 45 mph, coupled with the very cold actual air temperatures in
place, there has been very low wind chill values down to -55 for
these locations. As the gradient loosens by early tomorrow morning,
these winds will begin to diminish and allow for wind chill values
to also come down below the threshold. In addition, the troughing
over the North Slope has allowed for winds to become stronger and
gusty at times out of the southwest, and this may result in some
areas of blowing snow with reduced visibilities through tomorrow.
There are Special Weather Statements issued which highlight all of
these details. Models have continued to display a pattern change
with an area of low pressure approaching from Siberia, which will
allow for a return of some more mild temperatures as southerly flow
ahead of this system becomes predominant, with warming temperatures
beginning Thursday evening into Friday. This will also allow for
there to be a broad area of anywhere between 1 to 4 inches across
most portions of the Mainland, and even higher amounts for the
eastern Brooks Range, with some areas receiving up to 6-8 inches.

&&

.EXTENDED FORECAST DAYS 4-7...
Ensembles have been consistent in showing a large ridge
strengthening over the Bering Sea and over up into the Chukchi
Sea, and this will allow for much colder air advection to be
reinforced over the area. For the Interior, cold air will
reconsolidates, with widespread lows down into at least the -30s
and -40s F in the Central and Eastern Interior and the negative
teens in the Western Interior. Early next week, models depict a
strong ridge over the Bering Sea and Siberia with extensive and
very cold troughing over northwestern Canada. With a large, dry,
and very cold air mass aloft from Mon Dec 15 through at least Wed
Dec 17, where there could be -50s felt across much of the Eastern
Interior and eastern North Slope even outside of just the typical
cold spots.

Coastal Hazard Potential Days 3 and 4...None

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Cold Weather Advisory for AKZ835.
PK...Brisk Wind Advisory for PKZ814-815-861.
Heavy Freezing Spray Warning for PKZ817.
Heavy Freezing Spray Warning for PKZ851.
Small Craft Advisory for PKZ851.
&&

$$

Stewey

831
FXAK67 PAJK 100044
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
344 PM AKST Tue Dec 9 2025

.SYNOPSIS...

Key Messages:

- Snow continues for the central panhandle as an ample moisture
band moves overhead and below freezing temperatures persist.

- Cold temperatures continue, with many areas seeing single
digits or sub zero temperatures. Wind chills along White Pass.

- Partly cloud and breezy conditions through the week, with
potential for more snow in the southern panhandle late next
weekend.


&&

.SHORT TERM.../ through Wednesday night / Arctic boundary stalled
over south central panhandle. and moisture streaming into the
area so a band of snow forming on front from northern Prince of
Wales Island over towards Wrangell and Petersburg. It extends as
far north as Kake as well. Snow should continue through the
evening and then taper off. Another impulse will spread across
the southern panhandle Wednesday and it looks like the snow will
finally reach the Dixon Entrance area. Only minor snowfall
accumulations anticipated this time, but I`ve been surprised the
last few day.

Northern panhandle the cold weather ( wind chill ) for cold
advisories and gusty winds as well from the outflow. So nothing
surprising for the northern panhandle. Temperatures in the to
near zero or colder for the northern zones, and similar conditions
for Thursday morning as well it looks like.

.LONG TERM.../Thursday through Sunday/...Only minor changes were
made to the long term forecast, mainly adjusting outflow wind
speeds and pushing the potential snow for next weekend back a day.

By Thursday morning, the low moving south of the panhandle will
have moved inland into BC and dissipated, with strong outflow
winds keeping any developing showers offshore until Saturday
morning. This means that the panhandle will remain dry through the
rest of the week, with low PoPs and partly cloudy skies
dominating the forecast. A small surface ridge developing on
Friday is expected to make that day the most clear and the least
windy. Precipitation is expected to return to the forecast
Saturday morning as a low jumps into the southern gulf and sends a
front northward into the panhandle. Uncertainty still remains in
how far this front will make it through the panhandle, as
persisting outflow winds will attempt to force the front to stay
more southern. With colder temperatures remaining through the long
term forecast, precipitation will most likely fall as snow.
Active weather looks to remain into early next week.

The main concerns for the long term remain the temperatures and
winds. The arctic boundary continues to extend southward through
the week, keeping below freezing temperatures through the extended
forecast. Daytime highs will struggle to reach into the 20s for
many locations in the northern and central panhandle, and into the
30s for the southern panhandle. Overnight lows during the week
will mostly stay in the single digits up north and in the 10s down
south, slightly increasing through the weekend as the next system
moves in, though still staying below freezing. An extreme cold
warning for Skagway, primarily along the Klondike Highway, is
still active through noon Wednesday for extremely cold
temperatures as low as 45 degrees below. Cold weather advisories
for the Haines Borough and Gustavus have been issued through 9 AM
Wednesday for wind chills as low as 15 degrees below, primarily
once the sun sets. Strong outflow also persists through the week,
with 20 to 35 kt winds and pockets of gales blowing through the
inner channels and funneling out into the coastal waters of the
gulf. The strongest winds will remain in the northern panhandle,
particularly down Lynn Canal and Stephens Passage and out of Cross
Sound, with gaps along the gulf coast serving as outlets for
strong winds to funnel through. There will be a brief decrease in
wind speeds on Friday, though Lynn Canal will still stay above 20
kts before outflow ramps up even stronger than before going into
the weekend. Strong gales are expected to spread through a
majority of the inner channels, with strongest winds remaining in
those hotspots in the northern panhandle. Freezing spray will
remain an issue in the inner channels and along the NE gulf coast
with these elevated winds, which could become heavy at times.

&&

.AVIATION.../Through Wednesday afternoon/...Major changes from
this morning due to the arctic boundary retreating north of
Ketchikan this afternoon. As a result, far southern panhandle has
seen predominantly rain and less impacts on VIS, though still
occasionally down to 2sm in heavier showers. North of Ketchikan,
banded heavy snow showers combined with gusty winds in places such
as Wrangell, have lead to widespread LIFR conditions along
northern Clarence Strait/Prince of Wales Island up to Kake. Sitka
managed to get clipped as well, but is on the back end of snow
showers and should clear out over the next few hours.

Low CIGs AoB 1000 ft coupled with VIS below 1sm will continue for
a majority of tonight over the area mentioned above. As the low
moves into BC, expect Ketchikan to see a northerly wind shift and
snow mixing in. Another system is set to clip the far southern
panhandle Wednesday morning, giving another brief period of low
end MVFR or IFR conditions with some snow showers blowing through.
Outflow continues through the period so expect so light to
moderate turbulence flying through the channels, with continuing
LLWS for PAJN.

&&

.MARINE...
Outside: Strong outflow winds continue to dominate the
eastern gulf coastal waters through Wednesday. Gale to storm
force winds with strong storm force gusts are blowing out of
interior passes, as well as any available drainage channel. Only a
minor reduction in strength is expected through Thursday, but
winds are overall expected to stay elevated through the week. Wave
heights are around 7 to 10 ft through the majority of the gulf,
with areas affected by the outflow winds seeing up to 15 ft waves
persist through the week. Freezing spray is possible with strong
wind gusts, mostly along the coastal waters. The central gulf is
more calm, only experiencing disorganized moderate breezes as the
low in the western gulf dissipates.

Inside: Strong gale outflow winds have persisted through Tuesday and
are expected to continue through the week. A very strong pressure
gradient in the northern panhandle is forcing northerly winds with
gusts in the 60 kt range down through Lynn Canal and Stephens
Passage, as well as strong gale force winds with storm force gusts
out of Taku Inlet and through the rest of the inner channels. Wave
heights between 8 to 15 ft are expected in areas of the strongest
winds, with the rest of the channels seeing around 6 ft or less and
diminishing overnight. Channel entrances and areas with greater
localized forcing (like Point Couverden) may see up to 15 ft waves
at their peak. The pressure gradient is expected to only slightly
relax overnight, continuing gale force outflow winds in Lynn Canal
and Stephens passage and strong breezes to near gale force winds for
the rest of the channels through the week. Cold temperatures with
the strong gusty winds are leading freezing spray or Heavy freezing
spray levels that would result in coating ships/boats in ice.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Extreme Cold Warning until noon AKST Wednesday for AKZ318.
Cold Weather Advisory until 3 PM AKST Wednesday for AKZ319.
Cold Weather Advisory until 9 AM AKST Wednesday for AKZ320.
Winter Storm Warning until midnight AKST tonight for AKZ326>329.
Winter Weather Advisory until 3 AM AKST Wednesday for AKZ331.
MARINE...Heavy Freezing Spray Warning for PKZ011>013-031-053.
Heavy Freezing Spray Warning for PKZ021.
Heavy Freezing Spray Warning for PKZ032.
Storm Warning for PKZ013.
Gale Warning for PKZ011-012-022-031-033-642>644-651-662>664-671.
Small Craft Advisory for PKZ021-032-034>036-053-641-652-661-672.

&&

$$

SHORT TERM...Bezenek
LONG TERM...ZTK
AVIATION...STJ
MARINE...Bezenek

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