Graphical Hydro Meteorological Discussion

213
FXAK68 PAFC 171225
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
325 AM AKST Sat Jan 17 2026

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

A transient ridge of high pressure over Southcentral overnight
will retreat to the northeast today as the next storm system
approaches from the south. This morning, a warm front associated
with a deepening North Pacific low well south of the Alaska
Peninsula will move into the northern Gulf of Alaska. As it does,
snow will will develop over Kodiak Island early this morning
before easterly winds increase, driving temperatures above 32F and
changing snow over to rain.

This front will make it to the coast by this afternoon, spreading
snow over the Kenai Peninsula and across the Anchorage Bowl and
Mat-Su Valleys by late morning. Snowfall will generally be light,
on the order of up to 2 inches of snow, with most locations seeing
closer to an inch. Along the immediate coast of the eastern Kenai
Peninsula, snow is expected to change to rain by mid afternoon
Saturday as an easterly wind advects warmer air into locations
such as Whittier and Portage.

There will be a break in the precipitation by late Saturday
afternoon before the aforementioned low drives north, bringing
with it another round of precipitation. Temperatures aloft will
warm through the evening and overnight hours, especially across
the Kenai Peninsula and locations in the lee of the Kenai and
Chugach Mountains, resulting in the wintry mix of precipitation
once again. Freezing rain and snow is likely for a period of time
from Anchor Point north to Wasilla Saturday night through early
Sunday morning. Right now, it looks like areas along the Sterling
Highway from Anchor Point to Kenai may have the best chance for
prolonged freezing rain, with up to a tenth of an inch of ice
accumulation. A strengthening southeasterly flow aloft should push
the bulk of this wintry mix to the far western Susitna Valley by
Sunday morning, then lifting north along the Alaska Range by
Sunday afternoon as the low moves inland and weakens.

By Monday, a warm ridge will begin to set up over the state,
leading to a return of a much quieter weather pattern.

-TM

&&


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

This morning, an upper-level shortwave and weak surface low lift
north towards the Alaska Peninsula (AKPEN) between the Shumagin
Islands and Kodiak Island. The surface low will help to spread
precipitation, from south-to-north, today along much of the AKPEN.
While precipitation could start out as a quick period of wet snow
from Chignik to King Salmon, warmer air moves in from the North
Pacific and changes precipitation over to rain/snow mix or plain
rain by late morning or early afternoon before it ends. Light
precipitation makes it as far north as the Kuskokwim Valley and
Interior Bristol Bay by late morning or early afternoon in the
form of mostly snow in the Kuskokwim Valley, rain or rain/snow mix
across the Iliamna area, and snow turning to rain/snow mix across
much of Bristol Bay. The majority of precipitation from this
system will remain across Kodiak Island, Cook Inlet, and the Gulf
of Alaska.

Elsewhere, southerly flow continues across the eastern Bering and
through the southern AKPEN today as rain and or rain/snow mix
continues through today. A weak front moves to the Kuskokwim Delta
Coast and portions of coastal Bristol Bay tonight. The Kuskokwim
Delta Coast will see mostly snow from this evening while the
Western Capes and coastal Bristol Bay will see rain/snow mix as
warmer air works in. There is the possibility of some very light
freezing drizzle across the Dillingham area this evening as
precipitation encroaches on the area. This activity winds down
Sunday morning, as the Interior Kuskokwim Delta sees light snow
showers with what is left of the front.

Farther out west, a negatively tilted upper-level trough,
anchored by an upper-level low in the western Bering, extends
across the Western and Central Aleutians, including Adak and Atka
this morning. A surface low spins in the western Bering as it
retrogrades back to west through today. Its front moves over the
Pribilof Islands this morning as another shortwave helps to spin
up another low in the North Pacific south of Nikolski today. This
low will help to maintain light precipitation across the Pribilofs
through much of the day with light rain or light rain/snow mix
also continuing for Nikolski and Unalaska. Two more North Pacific
lows will lift northward into the western Bering, one Sunday into
Sunday evening and one Monday afternoon into Tuesday morning, will
affect mostly the Central Aleutians (Adak and Atka) with more
rain and or rain/snow mix as well as gale-force winds in the
marine zones near those areas. Scattered snow showers on the
backside of each system are possible along the Western Aleutians
including Shemya.

&&


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

Confidence is higher than usual for high pressure to build across
the state for the majority of the long range. Seasonable and
relatively quieter weather seems likely. A few surface lows may
make it into the Gulf of Alaska, but should remain confined to the
immediate coastline and potentially Kodiak Island. Similar is
possible for the Alaska Peninsula and southwestern coast. Farther
west though, low pressure will prevail with embedded surface lows
lifting north into the Bering Sea. Gale to storm force winds
possible. Each wave will move in succession through the Aleutians
and Bering Sea, keeping precipitation and winds in the Bering Sea
for most of next week. However, the main foreseeable challenge
would be with the timing of each low that lifts north across the
area.

Rux

&&

.AVIATION...

PANC...Light northerly winds will persist. Conditions will remain
primarily VFR, but there is a chance for MVFR conditions briefly
midday as a trough moves overhead with light snowfall.


&&

$$

148
FXAK69 PAFG 171435
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
535 AM AKST Sat Jan 17 2026

.SYNOPSIS...

Widespread winter weather and blizzard conditions have calmed
down early this morning across much of Northern Alaska, therefore
the majority of the posted hazards were allowed to expire early.
Blizzard conditions persist across the far western Seward
Peninsula to St Lawrence Island this morning before tapering off
from east to west through the day. Relatively dry conditions
expected today for the Interior and Arctic coast. Winds have
diminished through the Alaska range passes, but another shortwave
should increase southerly winds there late tonight into Sunday,
remaining below warning criteria. Another round of light snow
traverses the state from west to east, beginning in the YK Delta
and West Coast late tonight shifting into the Interior Sunday and
Sunday night.


&&

.KEY WEATHER MESSAGES...
Central and Eastern Interior...

- Winter storm conditions have largely come to an end, much drier
day expected for the Interior with highs in the 20s and 30s.

- Southerly gap winds across the Alaska range passes have
decreased, but expect them to increase again late this afternoon
into Sunday

- Light snow overspreads the Interior from west to east Sunday
with only minor accumulations possible

West Coast and Western Interior...

- Blizzard conditions continue early today for the western Seward
peninsula, diminishing through the afternoon as the main axis of
snow moves west. Worst conditions persisting for St. Lawrence
Island into this evening possibly.

- Breezy conditions along the west coast this morning diminish
through the day

- Another round of light rain and snow pushes in from the
southwest tonight before shifting into the interior on Sunday.
High temperatures near or above freezing into mid next week.

North Slope and Brooks Range...

- Snow diminishing across the Brooks range this morning

- Improving conditions and diminishing winds across the Arctic
coast today


- Much warmer temperatures with highs in the 20s and 30s above
Sunday and Monday, but expect increasing westerly winds.



&&

.FORECAST ANALYSIS AND DISCUSSION...

Satellite imagery this morning shows a low in the Bering with a
fetch of moisture stretching from the Central Pacific to the
Seward Peninsula while another weaker upper shortwave and
associated fetch push into Southern Alaska. Relatively quiet
conditions exist across Northern Alaska this morning as ridging
builds in overhead, with the far west being an exception. The
system in the Bering retrogrades toward Russia today as ridging
nudges westward, cutting off the main fetch of moisture and
working to end winter storm conditions. As ridging builds in over
the state, flow briefly becomes southwesterly this evening and
tomorrow with the occluding low in the Bering pushing an upper
level frontal boundary eastward across Alaska. Southwesterly
moisture advection and the incoming front produce additional light
rain/snow showers across the west coast tonight then spread
eastward through the interior on Sunday. The main threat for any
P-type issues and rain should be confined to the YK Delta where
surface temperatures are near or above freezing as a much warmer
airmass remains in place. Snow amounts should be fairly light this
weekend under a few inches. Heaviest snow showers expected along
southern facing slopes in the Brooks Range and on the Seward
Peninsula as orographic lifting and steeper lapse rates aloft
enhance lift and snowfall rates. Much lighter snow showers spread
into the eastern Interior Sunday evening, but overall little to no
concern with these.

The previously mentioned weak shortwave moving into the Southern
Coast of the state brings additional precipitation into the Alaska
range, however downsloping winds keep areas to the north dry. The
main impact with this system will be an increase in southerly
winds through the passes again this evening into Sunday. This
system is relatively weak compared to the previous one with winds
likely remaining under warning criteria in the passes. Downsloping
within this warmer airmass will likely bring temperatures above
freezing and potentially nearing the 40 degree mark the next
several days in areas just north of the Alaska range where the
downsloping effect is greatest.

The most noticeable weather change over the next several days
should be the widespread warmer temperatures across the majority
of Northern Alaska. The frontal boundary pushing through on Sunday
helps usher in an even warmer airmass with strong 500mb ridging
nearing 570dm...a type of ridge more common in the warmer
months... becoming centered over the state. Highs today reach the
30s across the west and Alaska range today. The warmer airmass
engulfs the rest of the state by tomorrow with highs nearing
freezing even on the North Slope.


&&

.EXTENDED FORECAST DAYS 4-7...

The extended period begins with an anomalously strong ridge
centered over the state bringing a welcomed mid winter thaw to
almost all of Northern Alaska. The warmer airmass remains in place
through midweek with the west coast staying warmer into the
weekend as the ridge axis shifts westward toward the Bering. Will
have to watch how guidance handles this pattern as there is
consensus among longer range guidance and ensembles that the ridge
remains strong and continues moving west into Siberia while
troughing over Northwest Canada pushes westward into Alaska. This
set up supports an arctic airmass slowly advecting back into the
Interior by the end of next week resulting in another cool down.
Confidence is increasing in another period of widespread below
zero temperatures by the end of the period into the following
week, but lower confidence still exists on finer details such as
extent of the cold and timing. For now, the longer range forecast
shows a slow cool down into next weekend with temperatures back
into the 0 to
-20 range going into the following week. The extended period will
be much drier for Northern Alaska with little to no precipitation
in the extended.



Coastal Hazard Potential Days 3 and 4...None


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Blizzard Warning for AKZ820-821-827.
PK...Gale Warning for PKZ801-802-850-851-854.
Brisk Wind Advisory for PKZ803-812-857-858.
Brisk Wind Advisory for PKZ804.
Brisk Wind Advisory for PKZ805.
Brisk Wind Advisory for PKZ806-811-817.
Brisk Wind Advisory for PKZ807.
Brisk Wind Advisory for PKZ809.
Brisk Wind Advisory for PKZ810.
Brisk Wind Advisory for PKZ816.
Brisk Wind Advisory for PKZ852.
Brisk Wind Advisory for PKZ853.
Brisk Wind Advisory for PKZ855.
Brisk Wind Advisory for PKZ856.
&&

$$

CM

587
FXAK67 PAJK 171404
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
504 AM AKST Sat Jan 17 2026

.SYNOPSIS...

Key Messages:

- Decent break in weather for much of the region through the
weekend and into the start of next week.

- Main threat to mariners and aviators is periods of dense fog,
most likely in the morning and evening hours.

&&

.SHORT TERM.../Through Saturday night/ Fairly quiet morning across
the panhandle with light winds and some patchy fog in isolated
areas (mainly Yakutat, Angoon, and Petersburg so far). Some high
to mid level cloud cover from the front in the gulf is streaming
over the northern half of the panhandle while the south is mostly
clear right now.

Short range forecast is expected to remain rather quiet as strong
high pressure in the Yukon spreads over the Panhandle and eastern
gulf. Aloft, a ridge spreading in from the SE is reinforcing this
quiet trend by deflecting all the storm tracks into south central
Alaska. The only main concern is how much fog are various areas
going to receive due to the breaks in cloud cover and the low wind
conditions. Not much developed this morning due to higher level
clouds, but there is a better chance for Sat night as skies are
expected to clear out a bit more which should allow more areas of
fog to develop. Otherwise winds are expected to remain mostly low
and temperatures will stay above normal.



.LONG TERM...Very little change for the long term, with continued
quiet weather and decreasing fog chances. A strengthening
mid/upper level ridge stretching from the Interior of the state
down through SE AK will divert would-be weather makers well away
from the panhandle. Warmer low level temperatures will help keep
high temperatures above freezing, although some areas will still
drop below freezing during the overnights. As the ridge
retrogrades into an omega block like feature to the west, building
high pressure in the Yukon will increase northerly winds, and
cooling temperatures.

&&

.AVIATION...Predominantly VFR conditions remain across the panhandle
this morning, with remnants of the system offshore still lingering
across parts of the northern and central panhandle this morning,
allowing for some drops to CIGs to AoB 2500 ft. These intermittent
drops to MVFR from CIGs dropping will continue into the morning
across parts of the northern panhandle before the remnants weaken
and fall apart into the late morning hours. Yakutat and Gustavus
alongside areas along the NE outer coast will continue to see the
drops to MVFR down to occasionally IFR longer into the day as the
low cloud cover is expected to linger from the system offshore.
Parts of Icy Strait corridor into the further northern panhandle
continue to see some chances for patchy fog development, before
chances are expected to diminish throughout the morning. However
conditions are expected to largely remain VFR with the exception of
Yakutat and Gustavus. Broken to overcast skies across the northern
panhandle will clear up throughout the day as the system offshore
weakens.

As the skies begin to clear into the early to mid morning for the
southern part of the panhandle, alongside the lasting light winds,
fog development is possible again into the morning. Currently
Petersburg and Angoon have seen some fog development and flying
conditions dropping down to LIFR with VIS 1 to 2 SM from the fog early
this morning, but other parts of the central and southern
panhandle may see similar trends with drops to MVFR down to IFR or
lower if fog develops in the next few hours.

Overall an improving trend is expected by late morning into the day
today, with skies clearing and winds staying light, and
predominantly VFR flying conditions expected around midday today and
lasting into tonight.

&&

.MARINE...
Outside (Gulf and Coastal waters): Relatively quiet marine
conditions in the gulf with most winds out of the SE to E at 20 kt
or less. Highest winds will likely be today into tonight before
diminishing into Sunday. Seas are the more pressing concern as
buoys are still observing around 9 to 13 ft seas driven by a S
swell of 9 to 13 ft (10 to 13 sec period). Seas are expected to
gradually subside to about 5 to 7 ft through Sunday as the south
swell subsides to 5 ft by late Saturday night. Seas will then
remain low through early next week at least.


Inside (Inner Channels): Low winds and seas are the rule this
morning with most areas showing 10 kt or less of wind. This is not
expected to change all that much through Sunday at least with the
only substantial change being that most winds have changed from a
southerly direction to northerly this morning and are expected to
remain from that direction through the rest of the weekend. Sea
remain low with most areas seeing 3 ft or less. Exceptions are
ocean entrances with a southerly exposure where the south swell
in the gulf will increase seas to around 10 ft or so Saturday
before the S swell subsides into Sunday. Some fog with visibility
less then 1 mile at times is also possible Saturday night as skies
clear out a bit more.


&&

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

&&

$$

SHORT TERM...EAL
LONG TERM...NC
AVIATION...Contino
MARINE...EAL

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