Graphical Hydro Meteorological Discussion

585
FXAK68 PAFC 051405
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
505 AM AKST Wed Nov 5 2025

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

An area of low stratus clouds and snow showers persists over the
western Kenai Peninsula, Cook Inlet, and western Susitna Valley
this morning as a weak trough lingers over the region. Farther
east, an upper-level ridge is extending from Northern British
Columbia and the Yukon Territory into the Copper River Basin.
Southerly flow between the ridge and a strong area of low pressure
moving north toward the southeastern Gulf is pushing a stream of
high clouds over the eastern half of Southcentral. Precipitation
is developing over the Gulf, along a surface front extending from
the aforementioned low. Temperatures early this morning range from
the teens and 20s along the coast and into the Mat-Su Valleys to
the teens and single digits across the Copper River Valley.

The forecast looks to be on track with regard to the advancing
area of low pressure, as this feature will become the dominant
weather feature for Southcentral through the next couple days
guiding the shift to a more active weather pattern. With low
pressure building over the Gulf and cold air building over the
interior of Southcentral, gusty northerly winds draining out of
the gaps such as Resurrection Bay, Passage Canal, and Valdez Arm
are expected to build Wednesday morning. Gusty winds through
Thompson Pass are also expected to similarly build, and given any
transportable snow on or near the roadways, may also lead to
periods of blowing snow through the pass at times of peak wind
gusts. Significant/continued reductions in visibility is not
expected, however periods are possible Wednesday morning through
Thursday morning. Wednesday night, precipitation is expected to
build across Prince William Sound, and eastern Kenai Peninsula.
Areas of the Copper River Basin may also see period of light
snowfall through Wednesday afternoon through early Thursday as
far north as Glennallen and Eureka.

By Thursday morning, snowfall will quickly build across the
eastern Kenai, pushing across the mountains and creating snowfall
near Portage, Turnagain Arm, and Turnagain Pass. Turnagain Pass
will see the quickest rise in snowfall rates, with accumulations
expected along the road system through Thursday. A Special Weather
Statement has been issued for this, please see that product for
more information. Later Thursday morning, the low will push
further north and west, allowing precipitation to persist closer
to the Anchorage Peninsula, with snowfall expected to begin for
the Hillside, with extensions into south and eastern Anchorage
possible, in the later morning. Snow is expected to continue for
these areas of the city through Thursday afternoon, as the low
shifts back into the western Gulf, retreating the snowfall back up
Turnagain Arm. Snowfall is likely to continue for the Turnagain
Pass area through Friday morning, although warmer air near the
surface along with easterly winds, should allow for snow to
changeover to rain for Whittier and Portage by Thursday afternoon.

-CL/TM

&&


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

An upper level low that has been drifting over the western
Interior over the past day or so is beginning to dip south into
the Yukon Delta this morning. South of this feature across
Southwest, stubborn areas of low stratus that developed yesterday
are still lingering across much of the Kuskokwim Delta and Bristol
Bay. Northerly winds are just now beginning to pick up across
Southwest, and this increasing northerly flow should help clear
out most of the lower level stratus as the day progresses. Some
of the lower cloud cover is already starting to erode across the
northern Kuskokwim Delta, but patchy fog is trying to form in
places as clearing allows near surface air to cool and saturate
where winds have not yet materialized. Across the Bering, the
pattern has become more nebulous and disorganized. A couple
trailing shortwaves are still moving across the central Aleutians
in the wake of a gale force low exiting into the North Pacific,
but the bulk of precipitation near this low is clearing out of the
region. Gusty north to northeast winds are still affecting much
of the central and eastern parts of the Chain, but winds will also
trend downwards with time today.

The outlook for the next few days is little changed compared to
yesterday. Across Southwest, the upper low approaching from the
north will swing across the Kuskokwim Delta this evening, then
down over the northern AKPen and Bristol Bay on Thursday.
Moisture near this system will be limited given the brisk, dry
northerly flow developing in the low levels. What snowfall we do
see will be concentrated over the Kuskokwim Mountains, where
intensifying northerly flow upslopes into terrain and wrings out
what moisture content there is to work with. Even so, there may be
a period of light snow that arcs across the Kuskokwim Delta right
as the upper low moves across, especially near and southeast of
Bethel. However, this should be a fairly brief and light round of
snow as the low brushes past, and most spots away from the
mountains are unlikely to see more than half and inch of new
snowfall through Thursday morning. Gusty northerly winds will
strengthen further on Thursday and persist into Friday as a
strong low shifts into the Gulf and as the low aloft stretches out
into more of a negatively-tilted trough over Southwest. Winds
will be strongest along and south of the Alaska Peninsula, where
gap flow will be enhanced both by cold advection and strong
northwest flow in the upper levels developing west of the trough
axis.

Looking to the west, the next feature of interest will be a weak
frontal system associated with a low moving along the Kamchatka
Peninsula. This front will bring a quick-hitting round of showers
(mostly in the form of rain) across the Aleutian Chain and western
Bering from this evening into Thursday. The front will begin to
lose steam as it approaches the Pribilofs and eastern Aleutians
from Thursday night into Friday, but it will likely still bring a
mix of rain and snow showers past before it fully shears apart
over the eastern Bering Sea. Later on Friday, attention will turn
to what is expected to become a rapidly intensifying low moving up
from the North Pacific into the far western Bering. The low`s
occluding front is expected to be quite strong as it heads across
the western Aleutians during the day on Friday, bringing a round
of Storm force winds and possibly Hurricane force gusts across the
western end of the Chain. Stay tuned as we follow this next
stronger system as it continues to head into the western Bering
Sea this weekend.

-AS

&&



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

Several strong storms will move across the Bering Sea from this
weekend through early next week. Of note is that models are in
much, much better agreement than is typical for this timeframe,
which suggests higher than usual forecast confidence with these
storms.

As mentioned in previous forecast discussions, the first storm
will be a low pressure system sweeping across the Bering
Sea/Aleutian Islands and into Southwest Alaska through at least
Monday. Models are honing in on a very strong low, with
deterministic models showing central pressure below 950 mb (and
as low as about 935 mb if the deterministic Canadian and GFS
models are to be believed). The primary hazard to watch for will
be hurricane-force gusts across the Western Aleutians/Bering.
Though the front will weaken as the low occludes, it may still be
strong enough to increase coastal water levels along the
Kuskokwim Delta coast Sunday morning. For most other areas, expect
widespread gales and moderate to heavy precipitation at times.

Forecast confidence declines from Sunday into Monday regarding the
position of both the occluding low and a triple point low that
forms along the front in the North Pacific. Regardless, expect
localized gales around both lows.

By Monday night, another strong low pushes its front across the
Bering Sea. Confidence is high that this will be gale force front,
with the potential for sustained storm force winds. This second
low won`t be as strong as the first low arriving late this week,
but it will be slower to occlude. As such, the front may be
comparable in strength to the first low`s front.

-Chen

&&

.AVIATION...

PANC...VFR conditions and light northerly winds are expected
throughout the TAF period. Northerly winds are expected to
increase with occasional gusts to 15 kt overnight Wednesday into
Thursday.

&&


$$

385
FXAK69 PAFG 051522
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
622 AM AKST Wed Nov 5 2025

.SYNOPSIS...
Showery weather continues across Western Alaska, with occasional
visibility restrictions there and on the North Slope and up to a
few inches of additional snow possible with ongoing snow over the
Western Interior. Farther east, moving into this evening and
through Saturday, a couple rounds of snow will bring varying
accumulations to much of the Central and Eastern Interior, with
totals of 1-4 inches in most of the southern Interior and on the
North Slope and higher totals up to 6 inches in the higher
terrain. Heading into Sunday and beyond, there will be additional
chances for snow and, with a front moving in from the west,
potentially some rain briefly mixing in. Cold weather is expected
to continue through the period, with some areas seeing highs fall
into the low teens or single digits early next week.

&&

.KEY WEATHER MESSAGES...
Central and Eastern Interior...
- Periods of light snow begin this evening and continue through
the weekend. Snowfall totals through Saturday:
* 1 to 4 inches in Fairbanks, Tanana Valley and AK Range.
* 3 to 6 inches in the White Mountains, Steese and Dalton
Highway Summits and southern Brooks Range.

- Chilly weather persists, and especially under any clear skies,
temperatures can drop to near or below 0.

- Otherwise, high temperatures (when clouds are present) will be
in the teens and 20s.

West Coast and Western Interior...
- Snow showers continue across Western Alaska today. Snowfall
totals through Wednesday:
* 1 to 3 inches east of the Nulato Hills (Kaltag, to Galena).
* 1 inch or less elsewhere.

- A weak front brings light snow from Hughes to McGrath east
Thursday afternoon and night with another inch possible.

- Temperatures remain chilly with highs in the teens/low 20s and
lows near or below 10 degrees with clear spots getting into the
single digits below zero.

North Slope and Brooks Range..
- Flurries and areas of fog are meandering around the North Slope.

- Snow will develop tonight around Coldfoot and move north
through Thursday morning. Periods of light snow are expected
from the Central Brooks Range to the Arctic Coast through the
end of the week. Snowfall totals through Saturday:
* Central and Eastern Brooks Range, 4 to 8 inches.
* Arctic Coast and Plains, widespread 2 to 4 inches with up to
6 inches possible near Toolik.

&&

.FORECAST ANALYSIS AND DISCUSSION...
The day again begins with troughing aloft across Western Alaska,
with a 518 dm upper low over the YK Delta/Norton Sound coast and
continuing light snow showers over adjacent waters. A wide stretch
of the Western Interior running from near McGrath northwest to the
eastern Norton Sound coastline/Seward Peninsula and north toward
Huslia is seeing persistent snowfall which will drop a few more
inches of accumulation today while gradually winding down into
the evening/night hours.

Heading into this evening and tonight, a shortwave will move off
of a low over the eastern Gulf of Alaska and move along the
Alaska/Yukon border. This will be followed by another shortwave
Thursday evening, which will move in a more southeast-to-
northwest direction, gradually crossing the state through Saturday
morning.

In terms of the model prognosis, the 06Z NAM, 00Z Canadian, and
00Z/06Z ECMWF runs are in good agreement on bringing at least a
few inches of snow to the Tanana Valley, including Fairbanks. The
06Z GFS keeps the area mostly dry until Friday, with potentially a
couple inches thereafter. With the second shortwave feature, the
Canadian and NAM runs and to a lesser extent the GFS bring in
another round of light snow Friday night into Saturday in the
Tanana Valley, Central Interior, Yukon Flats, Brooks Range, and
eastern North Slope. The ECMWF solution likewise brings at least a
couple inches of snow to these areas but is drier across the
Tanana Valley for this second round.

While there are still uncertainties on exact timing and amounts
of snowfall location-by-location, the general breakdown is that
this will yield between 1 and 3-4 inches across the Tanana Valley,
including Fairbanks, with higher accumulations of around 3 to 6
inches possible across the Western Yukon Flats, Upper Koyukuk
Valley, and Upper Kuskokwim Valley. Across the Central and Eastern
Brooks Range, totals will likely exceed 6 inches. Totals of 1-4
inches should be common on the North Slope as well. For all of
these snow events, snow-to-liquid ratios of 15-to-1 will likely
be common, with ratios closer to 20-to-1 or more possible.

Moving into early next week, another trough with plentiful
moisture may move through eastern Alaska and could bring
additional snow to the Central and Eastern Interior and Eastern
North Slope. There is low confidence in exact amounts and
locations. A storm over the Western/Central Bering Sea has the
potential to bring a front to the West Coast around the same time,
which could bring some offshore winds and rain/snow mix to
coastal areas. Cooling temperatures favor some areas seeing highs
fall into the low teens or singles digits.

&&

EXTENDED FORECAST DAYS 4-7...
Sunday into Monday, a low moving into the Western then Central
Bering Sea could push a front into the West Coast, which could
bring warmer air and a chance for rain mixing with snow, mostly in
coastal areas. It could also bring some offshore/easterly winds
during that time frame, although exact magnitudes are still
uncertain and will depend on the proximity of the low in addition
to its intensity. Monday afternoon into Tuesday, model guidance
tracks it into the southeastern Bering Sea while weakening it
significantly. In the Central and Eastern Interior, more light
snow and flurries are possible for most areas, with a chance for
another few inches of snow Monday into Tuesday. Another low with
another front is possible late in the extended time frame.

Coastal Hazard Potential Days 3 and 4...None

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...None.
PK...Small Craft Advisory for PKZ801-802-853.
Small Craft Advisory for PKZ803-852.
Heavy Freezing Spray Warning for PKZ804-815-859-860.
Small Craft Advisory for PKZ806-854.
Heavy Freezing Spray Warning for PKZ808-813-814-858.
Heavy Freezing Spray Warning for PKZ809-855.
Heavy Freezing Spray Warning for PKZ812.
Small Craft Advisory for PKZ814-855.
Small Craft Advisory for PKZ815.
Small Craft Advisory for PKZ850.
Small Craft Advisory for PKZ860.
Brisk Wind Advisory for PKZ861.
&&

$$

DS

185
FXAK67 PAJK 051824 AAA
AFDAJK

Southeast Alaska Forecast Discussion...UPDATED
National Weather Service Juneau AK
924 AM AKST Wed Nov 5 2025

.UPDATE...Aviation discussion for 18z TAF issuance.

&&

.SYNOPSIS...

Key Messages:

- A Gale force low continues to move north into the Gulf of Alaska.

- Marine and land winds continue to increase late tonight into
early tomorrow morning.

- Easterly mountain waves are likely to increase wind gusts up to
45 mph near Juneau Wednesday morning.

- Another gale force low slated for the weekend, bringing moderate
to heavy precipitation to the southern panhandle and then
spreading northward.

&&

.SHORT TERM...

.LONG TERM...A broad occluded low will move into the northwestern
gulf and send multiple shortwaves towards the panhandle to end the
week. Moderate to heavy precipitation is possible with these, but
nothing exceptional for this time of year. For the far northern
panhandle some mixed precipitation is possible, with minor snow
accumulations limited to the highest parts of the Klondike
Highway. There looks to be a brief break between these fronts
Thursday evening before the next wave moves through on Friday.
This second wave may have a little bit more moisture to work with
as models have it phase with a low passing south of the panhandle
around the same time. After this second wave, the low in the
western gulf is expected to continue weakening and dissipate,
being replaced by another strong low moving up from the eastern
Pacific.

This strong low will bring widespread precipitation beginning
later in the day Saturday and last through Sunday. Models have
begun to converge on a general track for this low skirting 140
degrees West before turning into the panhandle as it weakens. With
this feature being occluded at this point, there will be decent
moisture associated with it and moderate to heavy precipitation is
expected for the southern panhandle, with 48 hr accumulations
ranging from 2 to 4 inches as of this forecast, with lower
accumulations for the central and northern panhandle. These totals
may increase depending upon the low track, as the current
consensus is for the main moisture tap to aim for Haida Gwaii and
the central coast of British Columbia.

Current thinking is that while the lower levels across the
panhandle will be cool and there will be a northerly wind shift
ahead of the approaching low, temperatures will not be cold
enough for any appreciable snow accumulations at sea level this
weekend. However, with heavier precipitation rates, the
atmospheric column may be cooled just enough to allow for some.
This will be a very dynamic system to analyze and watch heading
into the weekend. Stay tuned for further updates throughout the
week.

&&

.AVIATION...A strong low in the gulf is driving a northerly and
easterly strong winds across the inner channels Wednesday morning
and will continue to do so throughout the day. LLWS will be the
primary aviation hazard along with turbulence as the low moves
northward in the gulf, with offshore flow at ridge top for the
northern panhandle, while the southern panhandle sees winds more
out of the SE aloft. The extensive cloud shield from the low is
providing a high overcast over the panhandle and northeastern gulf
of 10000 ft or more, with multiple layers below that above 3000
ft. CIGs are expected to primarily remain AoA 3000 ft, though
could drop below later tonight into Thursday as the low begins to
move away from the panhandle and an associated front pushes
northward. Drainage winds in the Chilkat Valley will continue out
of the northwest, meaning Haines could still see some mixed
precipitation making it down to the surface along with Skagway.
Overall conditions across the panhandle will primarily be VFR with
some drops to MVFR possible, though more likely to occur with the
next frontal passage Thursday.

&&

.MARINE...
Outside Waters: Easterly gale force winds across the majority of
the Gulf waters today with the strongest of these winds moving
from the southern Gulf northward as the low moves north into the
central Gulf by tonight. As the low moves northward, these
easterly gales will switch to a more southeasterly direction, with
the exception of off the northern and northeast Gulf coast
remaining easterly into tomorrow. Predominantly between 15 and 22
ft seas in the Gulf today through tonight, the highest wave
heights expected further north moving into tomorrow as the low
moves northward. SE swell expected throughout the day and into
tonight.

Inner Channels: Generally expecting N to NE 25 to 30 kt winds
across the northern inner channels, and E to NE 15 to 25 kt winds
across the central and southern inner channels this morning and
into today as the low is still to the southwest, keeping the more
SW-NE pressure gradient setup from the high to the northeast in
Canada. As the low moves northward during the day, the pressure
gradient will become stronger E-W gradient, decreasing some of the
northerly winds in the inner channels and strengthening the
easterly winds coming out of E-W oriented channels. Winds and
directions will fluctuate as the fronts move through, and as the
low in the Gulf moves westward into tomorrow, with the
predominantly NE winds shifting to a SE direction by late tonight
as a result. Gusty conditions are expected coming out of NE to E
channels this morning, with gusts to 30 kt possible in these
areas even with only 10-15 kt sustained winds, such as coming out
of Taku Inlet. Overall there will be a decrease in the winds this
evening into tonight, but winds will remain 15-20 kt across the
inner channels still as active weather continues. The strongest
winds across the inner channels will largely be seen this morning
through this evening before the low begins to move westward.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Strong Wind until 3 PM AKST this afternoon for AKZ325.
MARINE...Gale Warning for PKZ641-644-661>664-671.
Small Craft Advisory for PKZ011>013-021-022-031>033-036-053-642-
643-651-652-672.

&&

$$

SHORT TERM...Contino
LONG TERM...STJ
AVIATION...STJ
MARINE...Contino

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