495
FXAK67 PAJK 220007
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
307 PM AKST Fri Nov 21 2025

.SYNOPSIS...
Key Messages:

 - Showers continue filtering through the panhandle, with isolated
   thunderstorms possible into Friday night.

 - Winter Weather Advisory for the Klondike Highway has been
   cancelled early. Snow is still expected, but not at advisory
   levels.

 - Active shower pattern continues through the weekend with
   potential for outflow to develop early next week, bringing
   colder temperatures and drier weather

&&

.NEAR TERM.../Today and Tonight/...Forecast remains on track with
southwest onshore flow continuing to push showers into the
panhandle through the day Friday. Isolated thunderstorms are still
forming along the outer gulf coast through the afternoon, though
most lightning strikes have been concentrated in the Fairweather
range as convective potential begins to weaken. A weak shortwave
trough has rotated into the eastern gulf this afternoon and will
bring a bought of more organized rain to the panhandle Friday
evening. Only half an inch or less is forecast for the entire
panhandle, with northernmost areas expected to only see around a
quarter of an inch. Shower development is expected to ramp back up
behind the shortwave, with potential for isolated thunderstorms
directing into the central and southern panhandle.

The winter weather advisory for the White Pass area has been
cancelled a few hours early, as the bulk of the snowfall has
passed. Snow showers will still be moving through the area
overnight, with accumulations lessening into Saturday. Around 3
inches are expected at higher elevations, and periods of blowing
snow will be possible with gusty winds diminishing through the
night.

.SHORT TERM.../Saturday and Saturday Night/...Precipitation
continues its downward trend through the day on Saturday, with
showers becoming less numerous by Saturday night, with a respite
from the recent rounds of precipitation in sight for Sunday.

Aloft, the steering flow is finally shifting, with the rex block
over the interior of the state falling apart as the high pressure
to the north weakens, opening the way for the broad area of
troughing over the Gulf to be ejected eastward through Sunday and
Monday.

On Saturday, this will materialize in the lower levels as a
weakening low diving into the central Gulf. The low`s positioning
will ensure that the bulk of the shower activity stays offshore,
orbiting around the low, as onshore flow concurrently diminishes.
By Saturday night, PoPs will have dropped significantly across the
northern half of the panhandle as a result, although higher
chances of precip may linger for the far southern areas as a weak
shortwave sweeps in. Most areas near sea level will still see
precipitation fall as rain early on, though chances of snow mixing
in will rapidly increase in areas near sea level through the day.
Otherwise, snow is expected for mountain tops, with some
accumulation likely as well along the Klondike and Haines
Highways.

Temperatures will be on a general downward trend by Saturday
night as cold air advection from the western part of the state is
swept around the southern flank of the low and moves into the
panhandle. Winds will generally remain on the lower side, with 5
to 10 kt for many of the inner channels, and 15 to 20 kt for much
of the outer coastal waters. The main changes made to the forecast
were a downward trend in temperatures for some locations Saturday
night, along with an earlier changeover to mixed precip for some
locations, and lower wind speeds by lat Saturday in the inner
channels as the pressure gradient goes increasingly parallel.

.LONG TERM...For the start of the long term, current forecast guidance
looks similar to yesterday with a low persisting in the Northern
Gulf before weakening even further. Meanwhile, high pressure looks
to continue to build over the Interior and into the Yukon. With
this high pressure setting up, colder air will be able to slip to
the south. Current forecast guidance keeps most of this colder air
in the Yukon and away from the Coast Mountains. GEFS and EPS
guidance continues to still show some disagreement, especially
with the location of the high as it develops over the North Slope.
If the high can develop closer to the Yukon and British Columbia,
we could be looking at our first significant outflow event as
there is a potential for a low to move by to the south of the area
which could make for a tighter pressure gradient. This could
arrive just in time for the middle of the week allowing
potentially some of the coldest high temperatures we have seen
since last winter. But with the continued disagreement the
forecast is still trending towards a warmer solution. But this
will need to be watched through the weekend for any potential
changes. Otherwise, the extended forecast continues to be cooler
for next week before a potentially warmer and wet pattern returns
for the end of the month.

&&

.AVIATION...Widespread showers across the panhandle (especially
in the northern half) with embedded thunderstorms occurring along
the outer coast today (mainly from Baranof Island to Yakutat).
Some of those showers have been heavy with occasional drops in
visibility or ceilings to IFR. Convectively unstable conditions
are still dominate across the gulf and the overall SW flow pattern
has all of those showers that develop slamming into the outer
coast. Lightning detection has been lighting up all day along the
outer coast as the showers receive additional lift from hitting
the higher terrain with Sitka actually reporting lightning and
some small hail at times while Elfin Cove has seen some ice
pellets. These conditions are expected to continue through the day
and may last through late tonight as unstable atmospheric
conditions and SW flow persist across the panhandle and gulf.
Expect occasional lightning to continue along the outer coast
with the area of most frequent lightning likely extending down to
Prince of Wales Island this evening as a weak low moves inland.
The heavier showers may also have some ice pellets or small hail
and vis and ceilings may drop as low as IFR at times. Saturday
will feature less frequent and weaker showers as the instability
across the gulf becomes more stable and overall flow becoming more
southerly as the day goes on.

Gusty surface winds continue to be observed in the Lynn Canal,
Haines, and Skagway areas today and occasionally gusty winds are
also be observed near heavier showers. These wind conditions are
expected to continue and may be accompanied by some weak low level
speed shear (SE winds to 30 kt at 2000 ft agl) in the southern
panhandle this evening as a short wave moves into that area.
Expect gradually diminishing wind late tonight into Saturday.

&&

.MARINE...
Outside Waters: A broad swath of southwesterly fresh to strong
winds (17 to 27 kts) have persisted in the central gulf through
the day, and will steadily diminish overnight. 15 to 20 ft wave
heights with 15 ft of southwesterly swell at a 15 second period
will follow through the central gulf before quickly diminishing
below 15 ft into Saturday. Onshore flow continues to direct
showers into the panhandle with the occasional lightning strike
along the outer coastal mountains. The diminishing trend in the
winds continues through Saturday, alongside wave heights
decreasing to 8 to 12 ft by Saturday night.

Inside Waters: Showers continue moving through the panhandle with
southwesterly onshore flow directing winds up through the
channels. Fresh to strong southerly breezes (17 to 27 kts) in N/S
facing channels will be diminishing through Friday night, becoming
light to gentle breezes (4 to 10 kts) by Saturday night. Near
gale force gusts (28 to 33 kts) will persist overnight before
decreasing through Saturday, with potential for isolated gusts up
to low end gale force Friday night in Northern Lynn Canal and
Stephens Passage. 2 to 4 ft wave heights are expected for the
inner channels, with 10 to 15 ft wave heights for channel
entrances decreasing to below 10 ft by Saturday. There is a chance
for isolated thunderstorms to push into the southern channels
through Friday night.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ012-022-031-036-053-641>644-651-652-
     661>664-671-672.

&&

$$

NEAR TERM...ZTK
SHORT TERM...GFS
LONG TERM...SF
AVIATION...EAL
MARINE...ZTK

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