Graphical Hydro Meteorological Discussion

532
FXAK68 PAFC 100114
AFDAFC

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
514 PM AKDT Mon Mar 9 2026

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

The primary concern over the next several days will be the cold
and the gusty off-shore gap flow winds in the usual areas (Copper
River Delta, Valdez, Thompson Pass, Seward, Whittier, the Mat
Valley, etc) as an enhanced pressure gradient remains in place
over the coastal mountains. This pattern will remain firmly in
place as a shortwave trough passes through the northerly flow
aloft, strengthening those gradients through Wednesday.
Meanwhile, Eastern southcentral, particularly Thompson Pass,
Copper River Delta and Valdez, will get a quick shot of increasing
wind gusts Wednesday through Thursday as locations to the west
diminish due to a backdoor cold frontal passage - aided by upper
level 300 mb support; however, this enhanced support will quickly
pass before the end of the week. Under this dry and cold northerly
flow, reinforcing shots of Arctic air will help to keep the
aforementioned gradient in place in some form, as low pressure
drifts around the Gulf of Alaska.

AB/PP

&&


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

A very stable pattern will lead to continued cold and windy
conditions across the eastern Bering Sea and into portions of
Southwest AK the next few days. Perhaps more impactful, conditions
are perfect for large areas of extreme vessel icing across
Southwest AK coastal waters. Taking a look at satellite imagery, a
strong high amplitude blocking ridge is centered over the western
Aleutians and covers much of the western Bering Sea. Deep and
strong northerly flow east of the ridge is maintaining a bitter
cold airmass across the eastern Bering Sea and Southwest AK. Gusty
northerly winds can be found across the eastern Bering and down
across the eastern Aleutians (Nikolski, Dutch Harbor, Akutan) and
southern Alaska Peninsula (False Pass, King Cove, Sand Point),
Satellite-based freezing spray imagery shows extensive freezing
spray across marine areas along the Alaska Peninsula. Cold
Weather Advisories remain in effect along the southern Alaska
Peninsula for wind chills as low as 10 below zero. Winds have
lightened up across the rest of Southwest Alaska, so wind chills
are no longer a big factor. However, temperatures are well below
normal for this time of year, ranging from around zero to 10
degrees above zero. Lastly, a short-wave trough tracking down the
east side of the ridge is bringing snow showers and enhanced winds
to the Pribilof Island and central to eastern Bering Sea this
afternoon.

The upper level ridge will remain nearly stationary through
Thursday, resulting in very persistent weather conditions across
the region. The primary cause of fluctuations in the forecast
will be short-waves tracking southward across western AK and the
eastern Bering Sea. The short-wave in the Bering this afternoon
will move to the eastern Aleutians (Dutch Harbor area) and
southern Alaska Peninsula this evening, bringing a period of
steady snow showers and strong, gusty winds. This will exit to the
North Pacific by early Tuesday morning, but a reinforcing shot of
cold air advection behind it will produce snow showers off the
ice edge and down to the Eastern Aleutians/Alaska Peninsula. A
secondary fast moving upper level short-wave combined with the low
level cold air advection will strengthen gap winds along the
Alaska Peninsula and lead to expansion of marine areas covered by
heavy freezing spray and extreme freezing spray (potential for
4cm/hour or greater icing rates). Sub-zero degree wind chills will
persist across the Alaska Peninsula, where Cold Weather
Advisories remain in effect all the way through Wednesday.

Another short-wave will ride over top of the ridge and across the
northern Bering Sea Wednesday before diving southward Wednesday
night through Thursday. This will bring snow to portions of the
Kuskokwim Delta and down across the eastern Bering Sea to the
Alaska Peninsula. The airmass behind this doesn`t look nearly as
cold as what is in place right now and over the next couple days.
Thus, winds will be weaker, temperatures/wind chills more
moderate, and there will be less heavy freezing spray for marine
areas.

-SEB

&&


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

The long-term outlook suggests a complex atmospheric setup. An
upper-level trough centered over the northern Gulf of Alaska will
stretch southward into the North Pacific, serving as a hub for
several rotating shortwaves. While high pressure is expected to
dominate the Bering Sea through Sunday, the weather will shift by
Monday afternoon as an upper-level low arrives, bringing snow
showers to the western mainland.

Regarding local impacts, a tightening pressure gradient along the
coast will trigger intense winds through the gaps of the North
Gulf Coast. Additionally, strong northerly flow and cold air
advection will lead to gusty gap winds and frigid conditions
across the Alaskan Peninsula. Model guidance is generally in good
agreement in this pattern that will keep temperatures well below
seasonal norms for both South and Southcentral Alaska through the
end of the forecast period.

&&

.AVIATION...

PANC...VFR conditions and northerly winds will persist through
the TAF period. The northerly winds are expected to increase this
evening in conjunction with colder air moving into the region.

&&


$$

538
FXAK69 PAFG 092249
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
249 PM AKDT Mon Mar 9 2026

.SYNOPSIS...

Cold and generally benign conditions exist across the majority of
Interior Alaska today with the exception of a few locations along
the coasts observing blowing snow. Blizzard Warnings and Winter
Weather Advisories remain in effect through Wednesday for the
northeast Arctic Coast as strong west-southwest winds have
resulted in blowing snow and significantly reduced visibility at
times. Strong northwest winds through the Chukchi Sea and Kotzebue
Sound will persist for at least another 24 hours with blowing
snow also reducing visibility for coastal locations. The Interior
remains dry and very cold for Mid March with double digit sub zero
lows expected each day this week and possibly into the weekend. A
slight warming trend arrives for the West Coast by midweek as a
few weak systems traverse the Bering from the northwest increasing
clouds and chances for light snow.


&&

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

- Well below normal temperatures this week with daily morning
lows reaching the 20s to 40s...coldest spots being Interior
valleys.

- Expect large diurnal temperature fluctuations due to the strong
March sun with afternoon highs reaching the single digits above
and below zero.


West Coast and Western Interior...

- Gusty northwest winds resulting in blowing snow and reduced
visibility continue for portions of the northern Seward
Peninsula and Kotzebue sound through the next 24 hours.

- Below normal temperatures the next few days with double digit
sub zero lows, followed by a warm up to the teens above the
latter half of the week into the weekend

- Light snow accumulations possible Wednesday and Thursday for all
of the West Coast and far western Interior


North Slope and Brooks Range...

- Blizzard to near blizzard conditions at times due to blowing
snow and low visibility for the northeast Arctic Coast through
Wednesday

- At or below normal temperatures persist through the period with
double digit sub zero lows each day


&&

.FORECAST ANALYSIS AND DISCUSSION...

Cold and relatively dry conditions persist for Northern Alaska as
deep troughing over the state and Northern Canada and northerly
flow keep the storm track away from the region and an arctic
airmass in place near the surface. While the majority of the
interior remains dry, cold, and quiet through the weekend, a few
areas of more active weather exist for the Arctic Coast and West
Coast over the next few days.

For the Arctic Coast and Brooks Range, the region remains under
the influence of a complex upper low over the Canadian
Archipelago with numerous shortwaves rotating about it and into
the state. RAOB soundings from BRW show low to mid level
saturation below an inversion around 5,000 ft agl and based on
satellite imagery and observations, this sounding is likely
representative for the majority of the North Slope. Persistent
northerly flow and waves of energy should keep low to mid levels
clouds and snow showers around for the next several days. A
classic barrier jet has set up for the Northeast Arctic Coast from
Point Thomson to Barter Island resulting in gusty WSW winds,
blowing snow and very low visibility at times for this region. The
surface low in the high arctic and its associated barrier jet
remain in place through early Wednesday before ridging builds in
from the west. For the next 24 to 36 hours, expect similar
conditions to persist for the Arctic before a pattern change
arrives midweek.

Across the west, strong ridging both at the surface and aloft are
in place over the Bering keeping strong northerly flow through the
Chukchi sea and Bering Strait. Persistence is key when it comes to
the forecast for the next 24 to 36 hours as the synoptic scale
systems remain in place for now before more active weather arrives
on Wednesday. Northwesterly winds have resulted in blowing snow
and reduced visibility for portions of the northern Seward
Peninsula and toward Kotzebue, while the rest of the west remains
very cold and dry. Strong northwesterly flow is keeping the deep
arctic airmass in place and highs near or below zero with double
digit sub zero lows.

Outside of any active weather along the Coasts, the interior stays
very cold for this time of year as the aforementioned arctic
airmass remains in place and surface high pressure moves in
overhead. While conditions will be generally clear for the
interior, forecast soundings do show enough low level moisture in
place to support ice fog developing the next few nights,
especially as many areas make a run for -30F to -45F for overnight
low. The strong march sun angle should result in any fog
dissipating during the afternoon hours. Confidence on where and
when ice fog develops is low; however the upcoming pattern the
next several nights supports its development.



&&

.EXTENDED FORECAST DAYS 4-7...

Well below normal temperatures continue into the extended period
for much of Alaska. While a few systems bring light precipitation
to the West Coast, the interior remains cold and dry for the
foreseeable future. Upper troughing over the state and strong
ridging over the Bering have been keeping most of the storm track
to the south, with no big systems to kick out the arctic airmass
in place. Longer range guidance shows well below normal 850mb
temperatures in the -teens to -30C range through mid to late
month, supporting lows in the -20F to -40F range and highs
struggling to reach zero. Interior valleys will be the coldest
locations in this type of weather pattern.

Focus shifts to Wednesday through Friday as weaknesses in the
Bering Sea ridge allow for shortwaves to ride up and over it and
into the West Coast. Weak ridging shifts eastward setting up
across the North Slope and Western Interior as numerous elongated
shortwaves move in from Siberia and down into the Bering. With
most of the energy staying over the Bering, then sliding
southward, expect the best chance for any snowfall from these
systems to remain closer to the coast. The YK Delta along the
coast, northward to Nome and to the NW Arctic Coast and points
west likely will have several days of light snow Wednesday through
Friday with minor accumulations expected. A brief period of
relatively warmer conditions likely for the west coast during this
period as cloud cover, snow, and influence from the Bering Ridge
weaken the low level inversion and moderate the airmass slightly
allowing for temperatures in the single digits and teens above
zero.

For the North Slope and Arctic Coast, a subtle pattern change
arrives mid to late week. As shortwaves cut through the ridge
over the Bering and Siberia, a piece of the ridge breaks off and
shifts east extending from the Arctic Coast through the western
interior Wednesday, while surface high pressure sets up over the
North Slope. High pressure should shut off the barrier jet along
the coast, resulting in much calmer surface winds Wednesday
through the end of the week, especially along the coast where a
long stretch of blowing snow and low visibility had been occuring.
Subsidence under the high in addition to shortwaves now moving in
from the west/northwest should keep clouds and moisture trapped
in the lower levels for the latter half of the week. Relatively
benign weather only lasts a few days for the Arctic as additional
systems move in from the north by the weekend increasing winds and
chances for snow and blowing snow once again for at least the
Northeast and Northwest Arctic Coasts.


Coastal Hazard Potential Days 3 and 4...None


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Winter Weather Advisory for AKZ818.
Blizzard Warning for AKZ804-805-808.
PK...Brisk Wind Advisory for PKZ801-850.
Brisk Wind Advisory for PKZ802.
Brisk Wind Advisory for PKZ803.
Brisk Wind Advisory for PKZ805>807-852>854.
Brisk Wind Advisory for PKZ808-809-814-815-855-856-860-861.
Brisk Wind Advisory for PKZ810.
Brisk Wind Advisory for PKZ811.
&&

$$

CRM

635
FXAK67 PAJK 100540
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
940 PM AKDT Mon Mar 9 2026

.UPDATE...
06z Aviation update.
Moderate to heavy snow showers continue to be the primary threat
and challenge from the Icy Strait Corridor (PAGS/PAOH/PAJN) south
to Dixon Entrance. Any aviator attempting to navigate southeast
Alaska should plan on periods of LIFR to IFR snow showers, with
VFR in between. There is a decent signal that Juneau may hold onto
more frequent snow showers early Tuesday morning. Northerly
outflow winds will also continue to strengthen across the northern
Panhandle, primarily impacting Lynn Canal and Glacier Bay. For
folks flying the northern coast to/from PAYA, expect VFR to hold.

Snow showers will continue to plague the region Tuesday night into
Wednesday creating a complex aviation forecast. Plan on periods of
IFR from moderate to heavy snow showers.

&&

.PREV DISCUSSION......ISSUED AT 349 PM AKDT...

SYNOPSIS...

Key Messages:

- Widespread convective showers continue into mid week, with
chances of snow decreasing from north to south.

- Outflow conditions will continue to strengthen through the week
and peaking on Wednesday. Outflow will bring colder, dryer
weather for the northern half of the panhandle.

- Snow showers look to continue for the southern half of the
panhandle through midweek.

SHORT TERM...Complicated pattern going forward, with a very slow
moving, vertically stacked low in the eastern gulf bringing snow
showers into areas from Icy Strait down the the southern
panhandle. As such, very cold temperatures aloft and conditionally
unstable profiles up to around 600 mb are present. As of now,
showers are moving from the southwest towards the northeast,
primarily focused on an area from Prince of Wales Island up to
Kake and Petersburg. Furthermore, a band of convection has settled
over the Juneau area, with the only thing lacking is moisture.
Going forward into Tuesday, expecting to see this low pressure
move southward, shifting the storm direction of these showers to
be more moving northward rather than northeast. This is expected
to keep stronger showers away from Sitka, Petersburg, and
Wrangell, and increase the likelihood of shower development along
the eastern side of Baranof Island, including Tenakee Springs and
possibly Hoonah. As the low moves further south during the Tuesday
timeframe, Icy Strait including Juneau will see increasing dry
air aloft, limiting the amount of available moisture for showers.

LONG TERM...The main story for the mid to the end of week will
continue to be northerly outflow with a chance of snow showers over
the central to southern portions of SE AK. These showers will
continue to be variable allowing the heaviest showers to bring
moderate snow with reduced visibilities, and times of slightly
increased winds. The next wave of moderate to heavy showers is most
likely to move over the central and southern panhandle Wednesday and
Thursday as a band of higher vorticity moves northward. Currently,
highest accumulation looks to be over Prince of Wales Island with
the most likely solution of 2 to 4 inches in 24 hours with a low
chance of 20 to 40% chance of snow amounts near 6 to 8 inches. We
will continue to monitor these chances. The upper level low over the
gulf, along with the high pressure over the Bering Sea, will
continue to allow for northwesterly flow to bring cold air over the
panhandle. This will continue to slowly decrease temperatures as
well as keep the precipitation type as snow. The far southern
panhandle will still see times of rain or a rain/snow mix, but snow
will be the most likely precipitation type.

Otherwise, winds will continue to become northerly across the inner
channels with outflow winds building. All inner channel winds are
anticipated to become northerly by Thursday. Strongest outflow winds
will remain over Lynn Canal into Point Couverden, N Stephens
Passage, and Icy Strait with strong breezes to near gales (22 to 33
kts) through the weekend. Times of gale force winds (34 to 40 kts)
are also possible, most likely occurring Wednesday and Thursday over
Lynn Canal. For land winds, Skagway is likely to see strong winds
with a 50 to 60% chance of wind gusts near 40 mph on Wednesday.

This colder pattern looks to continue through the weekend into the
start of next week as the high remains over the Bering Sea. This
means that the next system that pushes into the panhandle will
likely bring more snow to the area due to the colder temperatures in
place. We will continue to monitor for when the next low pressure
system may arrive allowing for this change in pattern.

AVIATION.../ through Tuesday afternoon / Broad scale low over
the gulf persist through Tuesday staying quasi-stationary so
onshore flow will keep showers activity ongoing. Better snow
amounts for the coastal locations and then along the coast
mountains which ride higher shower catchers. VFR conditions this
evening, though should see stuff lower overnight so ceiling could
lower below 3000ft. The southern half of the panhandle should see
the worst of conditions.

MARINE...
Outside (Gulf and Coastal Waters): Somewhat stagnant pattern for
the outside waters, with a vertically stacked low drifting
southward through the next 36 hours. For the NE gulf coast, expect
to see a gradual increase in NE gap flow winds to a strong breeze
out of interior passes, including out of disenchantment bay. A
gradual decrease in westerly swell from north to south will lead
to a decrease in wave heights from 12-15 ft to 7-9 ft.

Inside (Inner Channels): Again, somewhat stagnant pattern for the
inside waters, with a similar story of a slow transition into
northerly winds in Chatham Strait, Stephens Passage, and Frederick
Sound. Main uncertainty with the short term is how fast the
transition from SE winds to NE, particularly near Five Finger,
and when it transitions to NE, will the winds also collapse down
to a gentle breeze. Otherwise, high confidence on the fresh to
strong breezes for Lynn Canal, down to the convergence point of
Point Couverden, with strengthening slowly through Wednesday.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Weather Advisory until 4 PM AKDT Tuesday for AKZ321.
Winter Weather Advisory until 4 AM AKDT Tuesday for AKZ325-328.
Winter Weather Advisory until 10 PM AKDT this evening for AKZ326-
327-329.
MARINE...Small Craft Advisory for PKZ012-013-022-053-641>644-651-661>664-
671.

&&

$$

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

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