502
FXAK67 PAJK 082011
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
1111 AM AKST Mon Dec 8 2025


UPDATE...update for the 18z TAF product. Minor changes if any
changes planned for the forecast MVFR and IFR for the southern
panhandle with VFR but LLWS and Turbulence for the northern
portion in the outflow pattern set up. Rain snow line about
Wrangell Kake to near Sitka line.

UPDATE at 11 am ... Upgraded winter weather advisory for Wrangell
and Petersburg to warning level through Monday evening due to
overrunning condition with arctic boundary south of them.

&&

.PREV DISCUSSION...ISSUED AT 615 am Dec 8...

SYNOPSIS...

Key Messages:

 - Moderate to heavy snow continues over the northern panhandle
   and will continue to spread southward into central and southern
   panhandle as temperatures decrease.

 - Cold temperatures moving into SEAK to start the week, with many
   areas seeing single digits or sub zero temperatures. Wind
   chills along White Pass dipping below -25 Sunday night.

SHORT TERM...The panhandle remains caught between two weather
patterns, with rain and snow across the southern panhandle
continuing on Monday while cold, drier air in the north works its
way southward as the arctic boundary is propelled along by strong
northerly outflow.

Satellite and radar imagery show precipitation continuing to try
and work its way northward as systems race into the panhandle.
The continuing advance of katabatic cold air outflow is shifting
these systems further and further south, with precip eroding away
as it encounters drier air racing down the inner channels. Areas
from the Icy Strait Corridor northward have largely seen heavy
precipitation come to an end, and chances of lingering snow
showers will diminish through Monday as drier air advances further
southward, with only minor additional accumulations at most
expected. For these areas, the big story will be the frigid
weather ahead, as temperatures look set to plummet over the next
few days, with wind chills reaching as low as 15 below for Juneau
and Gustavus, 25 below for the Haines Borough, and 30 to 40 below
for Skagway and the Klondike Highway.

Further south, snow and rain remain the major story. Precipitation
currently moving north through the central panhandle will be
reinforced by the arrival of another system, which will move
directly across the southern panhandle. This system will
successfully stall the arctic front, and even briefly send snow
levels back up across parts of the far southern panhandle
(including Ketchikan) through the day on Monday, before they
plummet in the wake of the systems departure Monday night. While
this brief surge in snow levels will not reach the central
panhandle, the moisture associated with the system will, and
consequently locations like Petersburg, Wrangell, and parts of
POW Island (the highways and more northern parts), will see some
moderate snow accumulations; with winter weather advisories in
effect. Ketchikan itself may see some minor snow accumulations
early Monday morning in more isolated areas (before the system`s
warm front has a chance to fully arrive), and Monday night, after
the system`s center has passed overhead, and Revillagigedo Island
finds itself on the NW flank of the departing low. One final
system will bring chances of PoPs (including some snow) to the far
southern panhandle on Tuesday. Beyond then, dry and cold weather
becomes predominant through the remainder of the week. For
additional details, see the long term discussion.

LONG TERM...An arctic boundary continues to move southward over the
southern panhandle at the start of the mid range and will likely
move south of the panhandle by mid week. Building high pressure in
NW Canada and interior Alaska is creating offshore flow and ushering
colder continental air through the northern panhandle. This air is
very cold with 850 mb temps plummeting into the -15 to -25 C range
by mid week across the northern panhandle and near -10 C over the
south. At sea level this will translate to overnight lows ranging
from single digits above or below zero for the north to teens and
20s for the south.

Daytime highs will struggle to reach the 20s for the north and into
the 30s for the south as we progress through the week. Coldest
temperatures look to occur Monday night through Wednesday night, but
sub freezing temperatures are likely to stick around into next
weekend as well. The panhandle from Icy Strait northward will be
watched closely as many locations will be approaching their
criteria for cold weather advisories or extreme cold warnings
(especially the Haines and Klondike Highways) from early to mid
week. As of this forecast discussion, an extreme cold warning was
issued for the Klondike Highway from Monday night through Tuesday
morning for extremely cold temperatures with wind chills as low
as -40 degrees.

Strong outflow winds will be ushering in these frigid temperatures,
blowing along many northern panhandle channels, with gale force
winds lasting through most of the week. The strongest winds will
be located along Lynn Canal and Chatham Strait, with elevated
winds also coming out of Taku Inlet as well as blowing out into
the gulf from gaps along the NE gulf coast. A strong 1035 mb high
in the Yukon is the main driver of this outflow and it will persist
and strengthen to 1050 mb by late next week. Expect gusty winds
out of many of the outflow areas in the northern panhandle to
start with, but expect outflow out of areas farther south through
the week as the Yukon high expands into northern British Columbia
by late week. With these winds and the cold air that it is
bringing, a few secondary effects will be noticeable. First, wind
chills will be rather frigid reaching into the negative teens and
possibly colder in the north most of the week. Second, is that
freezing spray will become a more widespread problem for many
marine areas in the inner channels and along the NE gulf coast.
The freezing spray could become heavy at times in Lynn Canal, near
Taku Inlet, and northern parts of Glacier Bay throughout the
week.

Otherwise, most of the panhandle will be dry through the mid and
long range except for possibly the south. A series of lows track
into the BC coast and could send some of their precip into the
southern panhandle throughout the week. Given how cold the
atmosphere is expected to be the precip, when it does fall, will
mostly be in the form of snow. Highest accumulations would likely
be earlier Tuesday, with additional accumulations will likely be
low for the mid week period. There is the possibility of a another
snow event for the south next Friday into Saturday with a couple
inches of accumulation possible but storm track is uncertain at
this time for that system.

AVIATION.../Until 12Z Tuesday/...Areas north of the Icy Strait
Corridor will remain in the VFR category through the 24-hour TAF
period. Areas in the Icy Strait Corridor & the central Panhandle,
Including PAJN & PASI will improve from the MVFR to the VFR
category by mid-morning. Areas farther south, including PAPG,
PAWG, PAKT, & PAKW will stay within the MVFR/IFR flight category
range through the period. Breezy / gusty conditions are expected
through the period with the strongest winds being in the northern
panhandle, especially PAGY & PAHN. LLWS magnitudes of up to around
30 - 35 kt out of a generally northeasterly direction for the
northern panhandle & out of various directions for the southern
panhandle centered at between 1 & 2 kft aloft are possible through
the period.

MARINE...

Outside (Gulf and Coastal Waters):

The outside waters forecast will largely be dominated by the
outflow winds from density differences between the panhandle and
north into Canada. Strong gales to storm force winds are expected
out of interior passes, Cross Sound, and Chatham Strait through
Monday, before some reduction in strength Tuesday through Thursday
as the pressure gradient orientation shifts. For more
information, see the short term discussion. For seas, expecting
to see upwards of 15 ft seas associated with winds blowing out of
interior passes for the next few days.

Inside (Inner Channels):

Strong northerly winds in Glacier Bay, Lynn Canal, and Taku Inlet,
with all these locations expected to exceed gale to strong gale
for multiple days, with the upper arms of Glacier Bay and northern
Lynn Canal expected to see heavy freezing spray for multiple
days. Looking to see the stronger northerlies to extend south on
Monday as the low/energy departs into British Columbia. Light to
moderate freezing spray is expected to stick around for the
central panhandle into mid week, with overall outflow conditions
persisting through at least the end of the week.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Cold Weather Advisory until 6 PM AKST this evening for AKZ318.
     Extreme Cold Warning from 6 PM this evening to noon AKST Tuesday
     for AKZ318.
     Cold Weather Advisory from 3 PM this afternoon to 3 PM AKST
     Wednesday for AKZ319.
     Cold Weather Advisory from midnight tonight to noon AKST Tuesday
     for AKZ320-325.
     Winter Storm Warning until 9 PM AKST this evening for AKZ326-329-
     331.
     Winter Weather Advisory until 3 PM AKST this afternoon for
     AKZ328.
MARINE...Heavy Freezing Spray Warning for PKZ011.
     Heavy Freezing Spray Warning for PKZ012-013.
     Storm Warning for PKZ651.
     Gale Warning for PKZ011>013-021-022-031>034-053-641>644-661>664-
     671.
     Small Craft Advisory for PKZ035-036-652-672.

&&

$$

SHORT TERM...GFS
LONG TERM...STJ
AVIATION...JLC
MARINE...GFS/N

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