Graphical Hydro Meteorological Discussion

430
FXAK68 PAFC 221321
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
521 AM AKDT Wed Apr 22 2026

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

Key Points:

* Unseasonably wet and windy weather is on the way for Wednesday
through Friday.

* The wettest weather will be the eastern Kenai Peninsula, Prince
William Sound, and the Susitna Valley with rainfall totals of 1
to 3 inches expected for most communities. Portage and Cordova
may see up to 4 inches or rain.

* Strong and gusty southeasterly gap winds will develop Wednesday
and persist through at least Thursday, with the first peak of
strongest gap winds likely late this evening into early morning
Thursday. Locations that will see some of the strongest winds
include Turnagain Arm, Anchorage Hillside, south to west
Anchorage, Palmer and the Knik River Valley, and Glennallen and
the Copper River.

The overall forecast is on track, with only minimal changes
overnight. These changes include an increase in magnitude of peak
wind gusts tonight for locations such as Anchorage, Palmer, and
Glennallen; a slight shift west in the track of the low moving
into the western Gulf and Cook Inlet for late Thursday into
Friday, and a slight increase in rainfall amounts for a few
coastal locations, especially Cordova, Portage, and Seward.

A large and deep vertically stacked low remains nearly stationary
over the southern Bering Sea. A strong short-wave lifting
northward along the eastern side of the trough is leading to
amplification of a downstream ridge, which extends across the
mainland. An atmospheric river extends from the tropical Pacific
northward to the Bering Sea low. While total precipitation values
are not all that impressive at less than 1 inch, this is the
driest time of year for Alaska and these values are 200% to 285%
of normal for the time of year. A frontal system is spreading out
from the low center across the northern and eastern Bering Sea. A
weak warm front continues to move northeast across the western
Gulf, with a general increase in cloud cover along with a band of
light precipitation moving across Cook Inlet and Prince William
Sound, Much of this precipitation is not reaching the ground as of
4 am, due to drier air near the surface aided in part by weak
southeasterly gap winds through typical locations.

On Wednesday, we will establish the large scale pattern that will
hold through the remainder of the week. The upper level flow will
continue to amplify and shift eastward, with the ridge ultimately
setting up shop over the eastern Gulf northward to the Yukon. This
will establish deep southerly flow and moisture transport from the
north-central Pacific to Southcentral. Multiple short-waves will
track from south to north through the week and combine with strong
low level southerly upslope flow to produce widespread significant
rainfall for coastal areas as well as the Susitna Valley. There is
some model spread in the track and amplitude of individual short-
waves which could shift the area of heaviest precipitation.
However, no matter the track of individual short-waves, the
eastern Kenai Peninsula and Prince William Sound regions will see
the brunt of precipitation and winds. Precipitation will fall as
all rain at sea level, with snow levels ranging from roughly 1500
to 3000 feet above sea level Wednesday through Friday. There seems
to be enough shifting of the location of heaviest rain as short-
waves and surface fronts move through, so no one location sits in
the heavy rain for too long. Based on this, do not expect
any flooding. However, will continue to monitor changes in model
guidance to ensure this doesn`t change. Inland areas from the
western kenai to Anchorage, the Matanuska Valley, and the Copper
River Valley will see some downslope flow, which will limit
rainfall duration and amounts.

-SEB/TM

&&


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

Stormy weather continues through Thursday afternoon as the region
remains under the influence of a Bering Sea low. Winter Weather
Advisories remain in effect for Nunivak Island, Kuskokwim Delta,
Kuskokwim Valley, and Lime Village through mid-morning today, as
warm air aloft will bring several hours of freezing rain. For the
Bering Sea and Aleutian Islands, expect sustained winds to gale
force as the low tracks just west of a line from Adak to Saint
Paul.

Expect quieter, but still unsettled, weather from Thursday
through Friday afternoon as weaker upper level shortwaves rotate
through the region. By Friday evening, a strengthening North
Pacific low begins its entrance into the Bering Sea, bringing the
next round of strong winds and moderate to heavy precipitation.
While the track of this low remains uncertain, it looks to be
stronger and likely more impactful than the storm moving through
today. Stay tuned.

-KC

&&


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

Unsettled weather continues across much of Alaska through the
weekend as a North Pacific low moves into the southern Bering near
Adak Sunday morning. The system tracks northeast past the Pribilof
Islands Sunday night and then slows west of Nunivak Island into
Monday. This will bring widespread gale-force winds across the
southern and eastern Bering and Bristol Bay, though the strongest
winds are expected to stay offshore. Coastal impacts look minimal
for now, thanks to shorefast ice and additional protection from
the extensive ice pack over the eastern Bering.

The front tied to this system will push into the western Gulf,
tapping into a steady stream of moisture. Coastal areas along the
northern Gulf, Kodiak Island, and higher terrain of the Alaska
Range will see the heaviest precipitation. Inland locations will
experience several days of lighter precipitation, with rain at
lower elevations and snow at higher elevations. A southeasterly
flow will also promote some downsloping, especially west of the
Chugach and Kenai Mountains, which could limit precipitation in
those areas.

Confidence in track has improved, with most guidance keeping the
low west to just northwest of Nunivak Island. This setup favors a
steady feed of moisture into Southcentral and Southeast Alaska.
One outlier (ECMWF) shifts the low farther west toward the
Pribilofs, which would increase winds and precipitation there,
but overall impacts elsewhere remain similar. As the system
weakens and shortwaves rotate around it, precipitation over
Southwest Alaska should gradually become less intense through the
first half of the week.


-LM



&&



.AVIATION...


PANC...Winds this morning will be out of the southeast and
generally remain light, ocassionally gusting to 25 mph. VFR
conditions are expected to persist through most the period, with a
slight chance conditions briefly dip to MVFR with any passing
rain showers, particularly this morning. Turnagain Arm winds will
increase through the day and remain active, with downslope flow
helping keep most showers out of Anchorage by this afternoon and
into the evening. However, a slight chance of showers moving over
the terminal remains.


&&


$$

267
FXAK69 PAFG 221315
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
515 AM AKDT Wed Apr 22 2026

.SYNOPSIS...

Leftovers of the upper level trough are expected to continue
making their way to the northeast, with the last remnants having
moved north of the North Slope by Wednesday morning. A ridge of
high pressure separates the outgoing trough and incoming low
pressure system. This strong low will be associated with a warm
front that is expected to bring blizzard conditions to much of
the West Coast through Friday, as well as scattered rain and snow
showers to the Interior and North Slope through the weekend. A
distinct warm-up is expected to begin for most of Northern Alaska
on Thursday, as a warm air mass will follow in the warm front`s
footsteps. Looking into the future, another low pressure system is
expected to approach the Southern Bering Sea early next week. This
system could bring more precipitation to much of Northern Alaska.

&&

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

- A Wind Advisory is in effect for the Eastern Alaska Range North
of Trims Camp for strong southerly winds between 35 to 45 mph
sustained and gusts up to 65 mph from Wednesday night through
Friday afternoon.

- A strong low pressure system moving north through the Bering Sea
early Wednesday morning and will be associated with a series of
fronts. This system will bring in rain/snow showers.

- The warmest temperatures so far this year are expected for the
region starting Thursday, with high temperatures in the low to
mid 50s through the weekend and next week.

West Coast and Western Interior...

- Blizzard Warnings have been issued for the Seward Peninsula, the
Kotzebue Sound Coast, the YK Delta Coast, and St. Lawrence
Island for heavy snow, gusty winds, and blowing snow from early
Wednesday morning through late Thursday/early Friday. Snow
totals could fall between 2 to 5 in over the Seward Peninsula
and 4 to 8 in over the YK Delta. Gusty winds could reach up to
60 mph over the general region.

- Following this system, high temperatures are expected to be
above freezing and could reach 40 above in some locations.

North Slope and Brooks Range..

- A strong low pressure system moving north through the Bering Sea
early Wednesday morning will bring in widespread snowfall
chances to the Brooks Range and Western North Slope starting
Thursday morning. Snow totals are expected to remain low, with
the highest accumulations expected for the Eastern Brooks Range
between 1 to 3 inches.

- Easterly/northeasterly winds are expected to pick up Wednesday
afternoon over the Dalton Highway Summits through Thursday
morning and Atigun Pass through Friday morning. Both areas are
expected to gust up to 25 to 35 mph.

- This week will see a significant warmup from temperatures in the
double digits below zero temperatures earlier in the week to
20s/30s above zero later in the week.

&&

.FORECAST ANALYSIS AND DISCUSSION...
Wednesday through Friday.

Residual precipitation from the upper level trough over Northern
Alaska is expected to continue traversing to the northeast, with
some lingering rain showers likely for the eastern portions of the
Interior and North Slope through Wednesday morning. These trough
remnants are being pushed out of the area by a ridge axis
extending from a 1030 mb upper level high pressure system in the
Gulf of Alaska. While this ridge is briefly over Northern Alaska,
generally cold and dry conditions are expected. Low temperatures
could reach below 0 in some locations going into Wednesday
morning, creating slick travel conditions over the Tanana Valley,
White Mountains, Forty Mile Country, and the Yukon Flats. Meanwhile,
over Southwest Alaska, a 970 mb triple point low will begin
impacting the Yukon-Kuskowkim Delta coast by early Wednesday
morning. 500 mb vorticity models depict a strong warm front
associated with the low gradually sweeping over Northern Alaska
through Friday and into the weekend. Blizzard Warnings are
currently in effect for the West Coast from Hooper Bay to
Kotzebue, and St. Lawrence Island, through late Thursday evening.
The majority of this region will experience very strong
easterly/northeasterly winds with gusts up to 60 mph. Blowing snow
is expected for much of the region. The Seward Peninsula could
see snow accumulations of 2-5 in, while the Yukon-Kuskokwim Delta
could see between 4-8 of snow between now and Friday.

As the triple point low`s warm front proceeds to travel across
Northern Alaska, it will eventually bring rain and snow to the
Interior and North Slope by Wednesday afternoon into Wednesday
night. Additional precipitation is possible through the weekend
in the same locations. Fairbanks and the surrounding areas will
likely see less than half an inch of snow accumulation.
Easterly/northeasterly winds are likely to briefly strengthen over
the Dalton Highway Summits Wednesday afternoon as the pressure
gradient above briefly strengthens. Gusts in this area could reach
25 to 35 mph between Wednesday afternoon and Thursday morning.
Additionally, southerly/ southwesterly winds are expected to pick
up Wednesday night through Thursday night through Atigun Pass with
the strongest gusts between 25 to 35 mph.

As the low moves into the Bering Sea, a strong south to north
pressure gradient forms in the Gulf of Alaska as the low interacts
with the west edge of the ridge axis. This will generate a 4 to 5
mb pressure gradient over the Eastern Alaska Range beginning
Wednesday night and continuing through Friday afternoon. Southerly
winds are expected to reach 35 to 45 mph sustained with gusts
reaching 65 mph, mainly through Isabel Pass. As the warm front
continues to travel in the northeast direction across Northern
Alaska, a warm air mass is expected to follow the front and
increase high temperatures drastically starting Thursday.
Fairbanks is likely to see high temperatures in the mid to low 50s
going into the weekend and next week. There is model uncertainty
with low temperatures over the next few days as they are expected
to hover around the freezing threshold. However, warm air
advection from this triple point low will likely support the start
of the spring-like conditions in Northern Alaska.

&&


.EXTENDED FORECAST DAYS 4-7...
Saturday through next Wednesday.

Precipitation, in the form of scattered rain and snow showers, is
likely to linger around Northern Alaska through the weekend. Rain
and snow mixes are likely over the YK Delta, Western Interior, and
North Slope before tapering off early Sunday morning. By Sunday
morning, another upper level low will reach the Southern Bering
Sea, bringing more rain and snow to the YK Delta. Confidence
remains low regarding rain and snow totals over Northern Alaska,
but it is likely that the Interior and North Slope may only
receive intermittent showers mid-week. By next week, high
temperatures are expected to have settled in the low to mid 50s,
creating well above freezing surface conditions over most of the
Interior.


Coastal Hazard Potential Days 3 and 4...None


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Wind Advisory for AKZ849.
Blizzard Warning for AKZ816>818.
Blizzard Warning for AKZ820>824.
Blizzard Warning for AKZ825-826.
Blizzard Warning for AKZ827.
PK...Gale Warning for PKZ801.
Gale Warning for PKZ802.
Gale Warning for PKZ803.
Brisk Wind Advisory for PKZ804.
Gale Warning for PKZ805.
Brisk Wind Advisory for PKZ806.
Brisk Wind Advisory for PKZ807.
Brisk Wind Advisory for PKZ808-809-812-855-858.
Brisk Wind Advisory for PKZ811-857.
Heavy Freezing Spray Warning for PKZ816.
Gale Warning for PKZ816.
Gale Warning for PKZ817-854.
Gale Warning for PKZ850.
Gale Warning for PKZ851.
Gale Warning for PKZ852.
Gale Warning for PKZ853.
Gale Warning for PKZ856.
&&

$$

Srinivasan

021
FXAK67 PAJK 221351
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
551 AM AKDT Wed Apr 22 2026

Key Messages:

- Benign pattern brings clearing skies and light winds through
the week. Dry and warmer conditions expected moving into the
weekend.

- High temperatures in the high 40s to 50s, steadily increasing
each day.

.SHORT TERM...

A quiet weather pattern has set up through the remainder of the
week across SE AK. As a mid-level ridge builds over the gulf,
high pressure continues to spread over the panhandle, and showers
will stay offshore and winds will calm down through Wednesday.
Rain chances start to return late Wednesday night for Yakutat, but
the ridge will block any westward progression of systems keeping
the rest of the panhandle dry. A low marine layer is expected to
develop in the gulf, which through the overnight and morning hours
will push inland along the outer gulf coast.

High temperatures in the mid to upper 40s are expected for the
northern and central panhandle, reaching into the low 50s in the
southern panhandle. Light winds are expected through the period,
but clearing skies may cause sea breezes to pick up through the
inner channels and for coastal communities midday through the
afternoon. Locations that see a significant amount of clearing on
Wednesday may feel sea breezes pick up which will keep temps along
the water from reaching the maximum potential highs, but inland,
sunny areas are more likely to hit them. Clear skies also mean low
temperatures may drop lower than expected overnight, though mid
30s to low 40s looks to be the current trend.

.LONG TERM.../Thursday through Sunday/...
Forecast for today trends towards the drier solution, bringing
clear skies and warmer temperatures more widespread across the
panhandle Friday into Saturday. The main changes in the forecast
are in regards to precipitation chances, with model guidance
coming to agreement on lower precipitation chances further into
the central and northern panhandle Friday through Sunday. Even the
EC has come further in line with the GFS and Canadian
deterministic and ensembles with keeping the ridging stronger over
the Gulf, making the panhandle stay blocked from the
precipitation as the main flow stays further west. Even the
Yakutat area remains a bit uncertain, as some models are
suggesting even lower chances of seeing precipitation Friday night
through Sunday, but largely keeps at least a chance of rain
through the weekend. The models seem to split beginning Sunday
night into early next week, but the weekend showing higher
confidence on a drier solution kept further westward may continue
into the extended timeframe if the ridge remains in place as the
low to the west attempts to push into the Gulf further.

Along with lower precipitation chances, the QPF amounts for the
Yakutat area have likewise trended downwards as the waves moving
through stay closer to Anchorage Thursday into the weekend. The
rest of the panhandle will see clearing skies from S to N Thursday
through the start of the weekend, with Saturday looking to be the
hottest day with clear skies looking likely across the panhandle,
with the exception of the NE coastline due to the onshore flow
and cloud cover. Temperatures largely unchanged, with highs in the
50s across the north / central panhandle to the low 60s for the
southern panhandle.

&&

.AVIATION...VFR conditions prevail over the panhandle with a
cloud deck around 2500 ft near the coastline. MVFR CIGs along the
outer coast are expected to persist through much of the TAF
issuance, and even spread inland near the Icy Strait corridor.
Original thoughts were more optimistic for persistent VFR in the
Icy Strait corridor, 3500 ft or above, but run to run guidance
combined with outer coast observations has increased confidence
for MVFR conditions later in the day with incoming clouds. It is
possible for these conditions to extend into the Ketchikan area,
but confidence is not high enough.

No wind, LLWS or precipitation concerns for this period, with
good VIS greater than 6 SM.

&&

.MARINE...
Outside (Gulf and Coastal Waters): Westerly winds of 10 to 20 kt
across most of the Gulf continue through Wednesday. The stronger
winds will generally be for the southern Gulf or in the vicinity
of Cape Spencer. Winds of up to strong breeze (~25 kt) are
possible in the Dixon Entrance. On Thursday, winds from Sitka
Sound Northward slowly turn out of the S, and even the SE near
Kayak Island, with gale force conditions (35 kt) possible Thursday
night for areas W of Icy Bay as a barrier jet sets up. Waveheights
of 5 to 9 feet on Wednesday (the highest waves in the southern
Gulf), will slowly subside through Wednesday night, dropping to 4
to 7 ft. Through Thursday, waveheights rebound somewhat,
especially in the northern Gulf. W Swell of 2 to 4 ft on
Wednesday weakens initially, before strengthening again on
Thursday as it shift more to the SW. A marine layer will result in
the potential for reduced VIS at times. Wave periods are
currently around 10 to 13 seconds.

Inside (Inner Channels): Moderate west to northwesterly breezes
in Sumner and Clarence Strait are expected to persist through
Wednesday. The rest of the inner channels are seeing relatively
calm winds and are expected to remain light through the period,
the exception being Lynn Canal, which will see periods of elevated
winds due to sea breeze effects.Channel entrances along the gulf
will likewise stay elevated through Wednesday.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ641>644-661>663.

&&

$$

SHORT TERM...GFS/ZTK
LONG TERM...Contino
AVIATION...NC
MARINE...GFS/ZTK

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