Graphical Hydro Meteorological Discussion

371
FXAK68 PAFC 051327
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
527 AM AKDT Sun Apr 5 2026

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

A negatively-tilted upper trough extends from Southwest Alaska
into the western Gulf this morning, with a weakening surface low
continuing to sit near the base of the trough east of Kodiak
Island. North and east of the trough axis, bands of convective
snow showers are continuing to affect much of the Gulf Coast and
Prince William Sound region, including near Whittier, Seward and
Homer. While most of this shower activity has stayed away from
inland areas due to drier air in place away from the immediate
coast, snow showers have occasionally worked farther inland
overnight in a couple places. A subtle shortwave trough moving
into the Susitna Valley has ushered a few snow showers into the
Mat Valley early this morning, while Anchorage has mostly just
seen virga overnight due to the dry air in place close to ground
level.

Looking ahead, the showery and unsettled pattern we`ve been in
for the past couple days will finally break tonight into Monday as
the trough axis over the Gulf lifts north towards the Copper
Basin. Areas of light snow could linger ahead of the trough across
parts of the Anchorage Hillside and eastern Mat Valley before the
trough lifts north late tonight into Monday morning. Otherwise,
expect generally dry conditions to return in between systems from
Monday into Monday night as a transient upper ridge moves
overhead. A lingering coastal trough coupled with strong
westerlies developing aloft will support offshore gap winds
picking up in the usual spots along the Gulf coast from late
tonight into Monday afternoon.

From late Monday into Tuesday, attention turns to the next system
expected to impact much of the forecast area early this week. A
large low moving over the Bering Sea will send a front across
Southcentral from southwest to northeast, first reaching Kodiak
late on Monday night. Temperatures will likely be warm enough for
precipitation to start as rain across most of Kodiak Island as the
front approaches. Farther north, the air mass in place has a much
better chance to support snow on the leading edge of precipitation
filling in ahead of the front as it continues to lift north
towards the Kenai Peninsula and southern Cook Inlet on Tuesday
morning. However, expect some issues with snow changing over to
rain during the afternoon hours as temperatures warm into the 30s
to low 40s. In addition, expect more of an upslope/downslope
signature to pick up in precipitation as southeasterly flow
increases out ahead of the frontal boundary. Much of the northern
Susitna Valley, eastern Kenai Peninsula and Prince William Sound
will continue to see steady rain and snow through Tuesday evening,
while much of the Mat Valley, Anchorage and interior Copper Basin
dry back out by Tuesday afternoon.

-AS

&&


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

Generally stormy weather expected for the Bering Sea, Aleutian
Islands, and Southwest Alaska through early next week as several
upper lows and troughs move through the area. Forecast confidence
is a bit lower after Monday afternoon, as there is uncertainty
regarding how these various upper level features will interact
with each other. While confidence remains lower, here are the
potential hazards we`re monitoring:

* Blowing snow for Kuskokwim Delta coast and Western Capes through
Monday, with visibilities to 1 mile or less possible.
* Moderate snow (on the order of about 6 inches total) for
northern Bristol Bay coast/Dillingham from Monday afternoon
through Tuesday afternoon.

Diving into the details... the current upper level pattern
features an elongated upper level low centered over Kuskokwim
Delta, ridging over the Aleutian Islands, and an upper low
approaching Adak and Atka from the west. Through this afternoon,
expect isolated to scattered snow showers around Kuskokwim Delta
due to the influence of the upper low overhead. Showers will taper
off through the afternoon as the low in the Bering Sea moves in.

The low currently in the Bering Sea will set up to be one of the
main players for this region`s weather over the coming days. Its
front will gradually move east, bringing rain and snow to the
Aleutian Islands through today, and the Alaska Peninsula/Southwest
Alaska by tomorrow. Depending on the temperature, there may be
periods of blowing snow. The Pribilof Islands will likely see a
period of blowing snow with minor visibility reductions this
morning, with more significant visibility reductions possible for
the Kuskokwim Delta coast and Western Capes tomorrow. Expect gusty
winds as well, especially through southeast oriented terrain gaps
like through Cold Bay.

This low and its front will merge with another low moving in from
the west, forming a broad complex. Uncertainty regarding the
various mesolows and surface troughs comprising this complex is
leading to uncertainty with the finer details of the forecast,
especially for the Alaska Peninsula and Southwest Alaska, so stay
tuned. Regardless, most areas will see a wet weekend and/or a wet
start to the workweek.

-KC

&&

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

A more active, progressive pattern looks likely by mid-week with
periods of increased cloud cover and chances for precipitation
across the Aleutians and much of the southern Mainland. Models are
in fair agreement through the first half of the period as an
upper level trough and accompanying surface low push precipitation
east across the state Wednesday and Thursday. Out west, a
Kamchatka low sends a front across the Aleutian Chain Thursday and
Friday, but the front weakens before reaching Alaska`s west
coast. Models begin to diverge late in the week with increasing
uncertainty regarding the timing and placement of upper level
shortwaves interacting over the Bering Sea and North Pacific. A
slight warming trend and seasonable temperatures are expected to
continue through the long-term across both Southwest and
Southcentral Alaska.

&&



.AVIATION...

PANC...VFR conditions and light winds will most likely prevail
for most of the TAF period. Due to mid level dry air in place,
models have continued to back off on precipitation chances, but an
isolated rain or snow shower cannot be ruled out. Ceilings are
also expected to gradually decrease through the TAF period,
solidly dropping below 5000` by 12z Monday or so.


&&


$$

169
FXAK69 PAFG 051233
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
433 AM AKDT Sun Apr 5 2026

.SYNOPSIS...
Clear skies, light winds, and seasonable temperatures continue across
the majority of our area Sunday. On Monday, a system arriving in
the Gulf of Alaska will cause light, wrap-around precipitation in
the southeast Interior and eastern Alaska Range. Scattered
flurries are possible in the southwest Interior on Monday, ahead
of a more substantial front arriving in the YK Delta Monday night.
This system brings widespread precipitation to the YK Delta and
Western Interior on Tuesday which should begin as snow, but turn
to a rain/snow mixture as temperatures warm above freezing Tuesday
afternoon. Light mixed precipitation continues east into the
Interior on Wednesday. In the latter half of the week, calmer
conditions look to return, with chances for another round of
precipitation in the West by next weekend.


&&

Central and Eastern Interior...

- Seasonable temperatures continue across the Interior, with highs
remaining in the upper 20s to low 40s. Lows will also trend to
being above zero regionwide, with localized colder spots below
zero.

- Starting Sunday evening, scattered snow showers are expected to
move into Fortymile Country, Upper Tanana Valley, and Eastern
Alaska Range with light accumulations possible.

- By early to mid next week, highs are expected to climb well into
the 30s to mid 40s, with lows in the teens/20s as cloudier
conditions return.

- Southerly gap winds through Alaska Range Passes will see an
increase Tuesday into Wednesday, with gusts up to 40 mph
possible.

- Increasing confidence supports a front moving into the Interior
Wednesday into Thursday with a mix of rain and snow showers as
even warmer temperatures build in.

West Coast and Western Interior...

- Isolated snow showers will continue across the YK Delta and
Southwest Interior region as the remnants of an upper-level low
track back northeast.

- Highs in the teens and 20s to low 30s further inland will
continue through the weekend, trending warmer in the Western
Interior to the mid to upper 30s by Sunday. Lows look to also
stay above zero in the single digits and teens.

- A front will arrive in Southwestern Alaska late Monday into
Tuesday and Wednesday. Precipitation will begin as snow Tuesday
morning, with a mix of rain and snow showers as even warmer
temperatures build in Tuesday afternoon.

- By early to mid next week, highs are expected to climb well into
the 20s and 30s to low to mid 40s further inland, with lows in
the teens/20s to low 30s further inland as cloudier conditions
return.

North Slope and Brooks Range...

- Mostly clear skies and dry conditions with light winds will
continue across the North Slope and Brooks Range into early next
week.

- Highs will mostly be in the single digits and teens through the
weekend on the Arctic Plains/Coast and teens/20s/30s in the
Brooks Range, trending warmer into next week.

- Overnight lows will continue to be coldest across the Arctic
Plains/Coast around -10F to -20F through early next week, with
above zero lows further south shifting north by midweek.

&&

.FORECAST ANALYSIS AND DISCUSSION...
We begin Sunday morning with a 548 decameter high over Mackenzie
Bay and a 525 dam low over the YK Delta. This pattern is resulting
in clear and calm conditions across the majority of Northern
Alaska. However, the low over the YK Delta becomes diagonally
stretched, extending from the Gulf of Alaska to the Bering Strait
Sunday night. The part of the upper low that that drops into the
Gulf becomes stacked on top of a deepening 1012 millibar surface
low moving north, pulling moisture along with it. As a result, we
see wrap-around precipitation make it up into the southeast
Interior Sunday night into Monday. Parts of the Tanana Valley
southeast of Delta Junction will see up to an inch of snow through
Monday. We may see scattered snow flurries in the southwest
Interior as well on Monday, as an upper-level ridge over the
Bering pushes the remnants of the YK Delta low farther inland.

Coming in from the southwest behind that ridge is a warm front. A
series of lows from the north Pacific are pulling warm moist air up
from the tropics. That moisture will be arriving in Southwest
Alaska sometime Monday evening. Initially, the precipitation type
should be predominantly snow, as temperatures in the YK Delta and
southeast Interior remain at or below freezing through Tuesday
morning. However, it should transition to rain or a rain/snow mix
as temperatures rise Tuesday afternoon. the front continues north
into the Western Interior and Seward Peninsula on Tuesday. High
pressure pulls a good portion of the moisture towards Anchorage
and the rest of South Central Alaska, reducing the overall impact
on Western Alaska.

Winds behind the front will be easterly and gusting into the mid
20s for areas in the YK Delta and likely above 30 mph for areas
along the Coast and for St. Lawrence Island. Southerly winds
through the eastern Alaska Range swell Tuesday, up to 40 mph.

&&

.EXTENDED FORECAST DAYS 4-7...
At the start of the extended, on Wednesday, the front from the
southwest will continue eastward into the Interior, providing
slight chances for mixed precipitation. High pressure quickly
reestablishes itself over mainland Alaska in the wake of this
system. Ensemble models are in relatively good agreement on
keeping this high pressure anchored over Alaska. As a result,
another low moving into the Bering on Friday takes a northerly
track through the Bering Strait. Precipitation should be limited
to the West Coast, and the gradient between the low and the high
pressure over Alaska creates strong southerly winds through the
strait.

Uncertainty surrounds exactly how much precipitation will move
from Western Alaska further northeast, with overall accumulations
regionwide expected to remain light. Warmer temperatures will
accompany this front as most locations south of the far northern
Arctic Coast see highs build well into the 30s to mid 40s with
overnight in the teens/20s.

The overall pattern change appears to shift high pressure farther
east from the Bering to mainland Alaska, potentially allowing
weak systems to travel up along the West Coast more easily.

Coastal Hazard Potential Days 3 and 4...None

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...None.
PK...Brisk Wind Advisory for PKZ851.
&&

$$

Troyke

451
FXAK67 PAJK 051404
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
604 AM AKDT Sun Apr 5 2026

.SYNOPSIS...
A more typical spring system will lift along the coast Sunday,
bringing moderate to heavy rainfall and some wind to our waters.

Key Messages:

- Widespread moderate to heavy rainfall in the central and
southern Panhandle Sunday.

- Rain spreads north through the day, reaching the Icy Strait
Corridor by the afternoon.


&&

.SHORT TERM...Early Sunday morning, much more typical spring
weather continues to march across Southeast, with an additional
system lifting along the coast, bringing some wind, warm air, and
rain. The instability in the lower boundary layer in the south, as
seen with the 4pm PANT sounding Saturday afternoon, will continue
to stabilize as a warm front moves over the Panhandle today, with
a transition to stratiform rainfall. For the Icy Strait Corridor
communities, expect rainfall to pick up later Sunday afternoon,
with rain moving north into Yakutat/Haines/Skagway Sunday night.
Warm southeasterly winds along ridgetops will increase to 30 to 40
knots Sunday, freezing levels will continue to rise or remain
well above the surface, reaching as high as 4000 ft over Prince of
Wales, and maintaining at 1000 to 2000 ft in the Juneau area.
However, on the backside of this system Sunday night, colder air
will bring increased instability and drop freezing levels back to
near or below 1000 ft, with heavier showers able to bring quick
hits of wet/heavy snow. Given the warm antecedent conditions, not
expecting much impact or accumulations, with the greatest threat
for aviators in reduction of visibility.


.LONG TERM...Precipitation continues into the very beginning of
the work week as a low pressure system pushes into the panhandle.
At this time, this low pressure system will also increase winds
across the gulf and for portions of the far southern panhandle.
Currently winds look to remain around strong breezes to low end
gales of 25 to 35 kts over the gulf. Winds and precipitation will
then both lighten through Monday and into Tuesday as a ridge
builds over the gulf. Strongest winds will continue to be over the
south, especially over the gulf with fresh to strong breezes of
17 to 27 kts continuing. Confidence in this high pressure sticking
around for a few days is high as deterministic and ensemble
guidance is in fairly good agreement for the middle of the week.
With the high pressure, there is the potential for a marine layer
to develop over the Gulf. The main impact from this marine layer
will be reduced visibilities that can impact marine travel.

Starting mid week, there is starting to be more agreement on a low
pressure system that will push across the northern panhandle and
then move SE across the area. Precipitation is most likely to remain
as rain, but times of a mix or snow are possible during the over
night to early morning hours for the northern panhandle. Behind this
low, another period of drier weather looks to return. Stay tuned as
we continue to monitor the extended period forecast and this finally
seasonal / spring like weather.

&&

.AVIATION.../Until 12Z Monday/...As an area of low pressure
continues to push northward through the southeastern gulf &
approaching the panhandle, reaching the PASI area late tonight,
area airports to the southeast of PAYA will experience CIG & VIS
conditions primarily in the MVFR flight category. Conditions may
temporarily dip down into the IFR category under the most intense
rainfall activity, especially as we move later on in the TAF
period. The PAYA area should improve by this afternoon to stay VFR
through the rest of the period with only VCSH as they will have
less influence from the aforementioned low. SFC winds may get a
bit gusty around the front associated with the low as it pushes
northward through southeast Alaska, especially for southern
panhandle areas. Also, for the southern half of the Panhandle,
along & out ahead of the front, LLWS magnitudes up at around 2 kft
of generally around 30 to 40 kt out of a southeasterly direction
are anticipated.

&&

.MARINE...
Outside (Gulf and Coastal waters):As of 3am Sunday morning,
satellite derived winds and buoy observations highlight ESE winds
of gentle to moderate breezes for the majority of our coast;
however, AMSR2 passes highlight fresh breezes near Dixon Entrance.
A variety of wave systems are present but for simplicity, the
dominant wave system is from the southwest, 3 to 4 ft at 9 to 11
seconds, with some southerly wind chop focused near 5 to 6
seconds. Significant wave heights near 5 ft. Over the course of
Sunday a low will lift along the coast, increasing winds to strong
breezes to near gales for coastal areas from Fairweather grounds
south to Dixon. For these areas, fresh seas will build to 7 to 9
ft out of the SE.

The primary concern with this system is the cold front on the
backside of the low Sunday night. Anticipate winds across the
eastern Gulf of AK to become WNW, with sustained speeds of near-
gale force, frequent gusts to gale force, generating fresh seas
from the WNW of 12 ft to 15 ft along our coast, with the highest
seas aimed toward the west coast of Prince of Wales.


Inside: As a system slides along the coast through Sunday, the
primary threat is an increase in winds for the inner channels,
with rainfall bringing more typical AK spring weather. Mariners
planning on navigating the region Sunday should plan for winds to
increase out of the E to SE, reaching speeds of fresh to strong
breezes (17 to 27 knots) as a warm front moves north. Mariners
navigating Lynn Canal will see less wind, with northerly gentle to
moderate breezes (7 to 16 knots) forecasted; however, the four
corners area to Young Bay and Pt. Couverden will see easterly
winds of fresh to strong breezes. Sunday night into Monday winds
begin to increase out of the WNW for waters along and south of
Frederick Sound, with the western coast of Prince of Wales likely
seeing the highest winds of strong breezes to near-gale force
conditions.



&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ022-035-036-641>644-652-661>664-671-
672.

&&

$$

SHORT TERM...AP
LONG TERM...EAB
AVIATION...JLC
MARINE...AP

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