620
FXAK67 PAJK 180040
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
340 PM AKST Wed Dec 17 2025

.SYNOPSIS...

Key Messages:

-Showers continuing south of Sumner Strait with snow accumulation
 expected late tonight into early Thursday.

-Northerly outflow continuing and strengthening across the north
 through the next few days with freezing spray becoming more
 widespread and temperatures becoming colder.

-Temperatures gradually cooling through late week across the
 panhandle.


&&

.SHORT TERM.../Through Thursday night/ Continued cold weather
with outflow winds for the north while the south will be cooling
down enough for snow tonight. Gale force winds continue to plague
the northern inner channels with freezing spray affecting a wide
area of the northern inner channels. Temperatures are starting to
decline in the north with some areas having reached single digits
this morning and staying in the teens this afternoon. Farther
south a trough of low pressure with more organized showers are
starting to move into the southern panhandle. Areas from Sumner
Strait southward had a wind switch this morning to southerly with
temps warming above freezing and any precip being a winterly mix
as a result.

Main trend for the forecast in the north is continuing outflow
with temperatures showing a steady decline through Thursday night.
Wind chills will be dropping as well with White pass reaching
extreme cold warning criteria Thursday evening, and Juneau and
Gustavus joining Haines with cold weather advisories Thursday
evening. Outflow in marine areas will likely remain nearly
consistent with gales and freezing spray over a wide area through
Thursday night.

Across the south (Sumner Strait southward) the trend is also
toward colder temperatures, but will also feature more snow,
especially by Thursday morning. Temperatures currently there are
in the mid to upper 30s with a southerly wind and some mixing of
precip, but temperatures are expected to gradually cool to near or
below freezing overnight as heavier precip cools the lower
atmosphere by snow melt cooling. Expect snow to start to
accumulate sometime tonight and the snow to continue into tomorrow
morning before tapering off. Accumulations are likely to be around
2 to 6 inches with the range in amounts due to the showery nature
of the incoming precip possibly favoring some areas rather than
others. Precipitation should continue to diminish into Thursday
night with temperatures continuing to showcase a downward trend.

.LONG TERM.../Friday through Sunday/... Overall outflow
conditions and colder temperatures are the main impacts the end of
the week through the weekend, as an upper level trough sets up
over the panhandle and a series of lows pass to the south into the
west coast of British Columbia. This will allow some slight
chances of precipitation to remain in the far southern panhandle,
but the low being situated to the south with a surface high over
the Yukon by Saturday and Sunday will allow for strong northerly
outflow across the northern panhandle and making its way into the
central panhandle through N/S channels. A stronger gradient also
sets up along the coastal mountain area to the NE into Saturday
morning, bringing stronger winds coming out of Taku Inlet and the
mouth of the Stikine River with the gradient remaining strong into
Monday morning. This stronger gradient for this weekend will allow
for some stronger NE 925 mb winds, which have already been
showing through the long range models around the Juneau area. This
strong cross barrier flow expected Friday evening through Saturday
and into Sunday is also expected alongside weak 500 mb winds over
the panhandle as the trough sets up over the area, creating a good
critical level from this no flow area just over Juneau. The last
ingredient is the inversion expected over Juneau between 900-800
mb, and all together these all being expected for the Juneau area
this weekend bring confidence at a Taku Wind event. At this
time, uncertainty still remains at exactly how strong these wind
gusts will be and the exact timing of it during the weekend, but
confidence is high for over 60 mph gusts Saturday and potentially
lingering longer into Sunday if these favorable conditions stay in
place for longer.

Along with this outflow and stronger northerly winds pushing down
through the panhandle this weekend brings colder temperatures into
the weekend, with the decreasing temperature trend this week
lasting well into Saturday and Sunday. This will bring surface
temperatures to just around 0 degrees F and down into the
negatives as the minimum temperatures this weekend for the
northern panhandle at sea level down to parts of Icy Strait
Corridor, and with the wind chill temperatures the northern
panhandle from Skagway and Haines down to Gustavus and Juneau have
a Cold Weather Advisory in effect Thursday through Sunday for
Juneau and Gustavus, starting tonight for Skagway and Haines and
lasting into Sunday as well. The highways will see even lower
temperatures at elevation, alongside dangerous wind chill
temperatures. This brings Skagway up to an Extreme Cold Warning
lasting Thurday Heavy freezing spray will also continue to be a
hazard into the weekend due to the cold temperatures and strong
outflow conditions. These cold, dry, and windier outflow conditions
are to continue into early next week, however the coldest
temperatures at this time are expected Saturday and Sunday.


&&

.AVIATION...
The northern and central panhandle continues to see
overall VFR conditions with strong outflow winds, mainly over
Skagway and Haines. Skagway is likely to see wind gusts up to 35 to
40 kts, increasing Thursday. Yakutat could see some increased wind
shear as outflow continues to increase. This brings areas of
increased winds around 2000 ft up to 30 kts, slightly south of the
Yakutat airport. Juneau is also likely to see continued wind shear
around 25 kts at 2000 ft, lasting throughout the TAF period.

Snow showers have reached areas around the south central panhandle,
Sitka, Petersburg, and Wrangell airports. This snow has reduced
flying conditions at times to MVFR and even IFR with visibilities as
low as 1 SM. Snow showers are going to continue through late tonight
with a few short breaks. Then conditions will start to improve late
tonight into early Thursday morning with a few light lingering
showers. By tomorrow late morning/afternoon, ceiling and visibilities
improve to VFR.

The southern panhandle will have the most impacts throughout the TAF
period as snow showers continue over the area and then more
organized bands of snow move over the area this evening into
tonight. There have already been times of lowered visibilities and
ceilings due to snow, reducing flying conditions to primarily IFR
with times improved conditions to MVFR and on the flip side, times
of reduced visibilities to LIFR. This story will continue into late
tonight for the southern panhandle with times of MVFR with lighter
snow and IFR when snow becomes moderate to heavy allowing for
visibilities to decrease. We will start to see conditions improve
for the southern panhandle Thursday morning as the low pressure
system moves east and the organized precipitation bands diminish.

&&

.MARINE...
Outside (Gulf of Alaska/Coastal Waters):
Easterly outflow winds continue to scream out of Cross Sound, with
Sumner/Chatham ocean entrances reporting near-gale force
conditions. Coastal buoys are reporting southerly swell at 7 to
10ft and a period of 10 to 12 seconds. This swell, combined with
outflow winds, are creating large and confused seas, especially
near Cross Sound and the Fairweather grounds. This trend will
continue through Friday before winds slightly weaken. This break
will be short lived; strong gales will be felt at Cross Sound and
the Fairweather grounds by late Saturday. Moderate freezing spray
is likely near major bays and river outlets along the northern
coast, with the 45F ocean temperatures being the limiting factor.

Inside (Inner Channels):
Strong gale force outflow winds continue to pummel the inner
channels, with the most danger in areas along and north of the Icy
Strait Corridor (Cross Sound east to Taku Inlet) and Stephens
Passage. Expect winds to continue and/or increase Thursday as the
pressure gradient tightens between the Gulf of Alaska and Canada;
however, sustained winds should remain within strong-gale force,
with gusts to storm force. Seas of 12 to 17 ft will continue to
impact Lynn Canal and northern Chatham. Heavy freezing spray is
expected with higher confidence the closer you are to Canada.
Mariners should heed caution with these dangerous conditions.
Outflow winds will persist through the weekend.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Cold Weather Advisory until 6 PM AKST Thursday for AKZ318.
     Strong Wind through Thursday afternoon for AKZ318-325.
     Extreme Cold Warning from 6 PM Thursday to noon AKST Sunday for
     AKZ318.
     Cold Weather Advisory from 6 PM this evening to noon AKST Sunday
     for AKZ319.
     Cold Weather Advisory from 6 PM Thursday to noon AKST Sunday for
     AKZ320-325.
     High Wind Watch from Saturday morning through Sunday morning for
     AKZ325.
     Winter Weather Advisory until noon AKST Thursday for AKZ328.
     Winter Weather Advisory from 9 PM this evening to 3 PM AKST
     Thursday for AKZ330-332.
MARINE...Heavy Freezing Spray Warning for PKZ012.
     Storm Warning for PKZ012.
     Gale Warning for PKZ011-013-022-031-032-053-642-643-651-663-671.
     Small Craft Advisory for PKZ021-033>035-641-644-652-661-662-664-
     672.

&&

$$

SHORT TERM...EAL
LONG TERM...Contino
AVIATION...EAB
MARINE...AP

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