Petersburg, Alaska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

069
FXAK67 PAJK 240028
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
328 PM AKST Tue Dec 23 2025

.SHORT TERM...The cold weather continues for the panhandle as some places
managed to set record cold temperatures today. The cold weather
is expected to continue tonight as similar conditions to last
night are expected. One concern will be just how cold locations
across the northern panhandle get as temperatures this morning
were quite cold. High wind gusts remain possible for the Skagway
area through this evening but the concern for high winds in the
Downtown Juneau have diminished as the mountain wave is not
looking to be as big of a factor now. Headed into Christmas Day, a
low moves out of the Interior and move across the northern gulf
before working south and east. This will bring some snow to the
outer coast from Sitka south to Prince of Wales Island. Most
accumulations look to remain under a few inches but will reinforce
the cold air across the area. Concern then turns to the long term
for the next impactful system to move into the area.

.LONG TERM...We continue to watch the upcoming shift in the
weather pattern that would give the next round of significant snow
to Southeast Alaska.

The next major system will begin to move into the Gulf of Alaska
Friday, following behind the weak low clipping the panhandle
Thursday. As the weaker low moves southeast, before the larger low
approaches from the west Friday night, there will be another brief
lull in the winds into Friday along the southern waters, while the
northern offshore flow will remain stronger ahead of the next low
moving in from the west. Winds begin to pick up across the entire
panhandle Friday night into the weekend as the stronger low
approaches, and a gale force front begins to move in from the
southwest. These southerly winds moving into the panhandle will
allow for some warming across the panhandle alongside bringing
precipitation through from W to E into the start of the weekend.

As far as temperature relating to snow potential, the EURO and GFS
ensembles and deterministic models have come into greater agreement
over low tracks and 500mb flow. The Canadian remains the outlier.
The 500 mb flow continues to have the deep trough further west,
keeping a southwesterly flow into the panhandle and allowing for
deep moisture and warmer air to be moved in from lower latitudes
with the deep trough position, with the arctic trough and 500 mb
cutoff low over the Pacific to the southwest connecting over the
Kenai Peninsula down the west Gulf. Some of the deterministic models
show the arctic trough separating from this lower latitude troughing
as it becomes a cutoff again and moves southward, leaving a
southwesterly flow into the southern panhandle but the arctic trough
allowing for colder arctic air to move across the northern Gulf into
the northern panhandle, bringing the potential for cooling the north
much sooner than the southern panhandle into next week. This has not
been shown on the ensembles as of yet, and is seen on the EC
deterministic run and not the GFS one, so the certainty of the
timing of the cold air coming back into the northern panhandle is
still a bit uncertain for the period into early to mid next week.

Looking at the EFI tables, as well as looking at AR and IVT tools
for this heavier precipitation coming up this weekend, QPF amounts
have been adjusted to keep the southern panhandle at between 2.5 and
3.5 inches of liquid precipitation every 24 hours, coming down first
as snow Saturday morning before quickly transitioning to rain from
the SW coastline inwards as the warm front pushes through, with the
switch to rain expected during the morning hours for PoW and Sitka
into midday for areas like Ketchikan and Wrangell that are a bit
further inland. This is from the extreme and AR tools showing a
higher confidence of a shift of tails for QPF for the southern
panhandle, particularly near the Ketchikan area, with an increased
confidence from yesterday`s model runs. Overall the heavy rain will
begin for the southern panhandle Saturday, but the next wave of
precipitation pushing through will bring another round of heavy rain
Sunday that has been primed by the first warm front pushing through
the day prior. The warm temperatures in the high 30s to low 40s will
continue into the early week as onshore flow continues to bring in
southerly warmer flow into the southern half of the panhandle.

For the rest of the panhandle, which includes everywhere north of
Wrangell and Sitka, the snow will last into Saturday as that first
front moves in, as the warmer temperatures will not bring
temperatures up into the mid to high 30s until Sunday. This will
allow for a switch to more of a mix potentially becoming rain by
Sunday afternoon/evening up to Icy Strait corridor. These areas will
see between 8 and 14 inches in 24 hours Saturday into Sunday morning
before transitioning to rain/snow mix to potentially rain. Snow will
start off lighter and fluffier Saturday as snow liquid ratios remain
high, but as the area warms Saturday into Sunday, ratios will
decrease to become a heavier and wetter snow. Areas to the north of
Icy Strait corridor will likely remain snow the entire time
through both fronts moving through, giving a significant amount of
snowfall to the Skagway and Haines areas with between 10 and 18
inches in 24 hours both Saturday and Sunday with more expected
along the Klondike Highway. However these amounts for all of the
panhandle depend largely on how much of the precipitation actually
reaches parts of the panhandle, particularly in these northern
areas. Overall the northern half of the panhandle will see 1.5 to
3 inches of liquid precipitation during this system, but there
remains uncertainty on how much snowfall there will be exactly
during this system and the exact timing of a changeover to rain
for the central parts of the panhandle. Overall this will remain
more of a heavy rain event for the southern panhandle from Sitka
and Wrangell southwards Saturday into Sunday, with only about 3 to
7 inches expected for Ketchikan Sitka and PoW Saturday morning
before transitioning to rain, and 6 to 12 inches for Wrangell
possible before they too transition to rain.

&&

.AVIATION.../through Wednesday afternoon/...
Mainly VFR flight conditions expected through the period. Across
the north, just a few passing high clouds expected. Further south,
Generally VFR flight conditions with skies few to sct AOA 3kft.
Snow showers could bring brief MVFR VIS/CIGs for PAKT tonight.
Low level turbulence and wind shear will also persist with winds
1-2kft aloft 25-35kts. Strong winds 25g50kt continue for PAGY with
breezy outflow winds 12-17G22-30kt for PAHN, PAWG and PAKW. Less
than 10kt elsewhere.

&&

.MARINE...
Outside (Gulf and Coastal Waters): Outflow winds continue across the
Gulf. The strongest winds continue to be out of gaps in terrain such
as Cape Spencer and near Dangerous River. These winds continue to
weaken somewhat but some locally stronger winds remain possible as
we head into the middle of the week before starting to weaken. Wave
heights are expected to diminish for most of the Gulf but the
largest waves will persist in the areas where the outflow winds
continue to remain high. The N-NE swell is expected to shift to a S-
W swell component by the time we get to Wednesday. Waveheights are
then expected to increase as a low ejects of the Interior Wednesday
which will bring up heights.


Inside (Inner Channels): Outflow winds continue this afternoon as
the wind speeds continue to remain elevated with gales to strong
gales continuing for Lynn Canal and Stephens Passage. Outflow winds
are expected to increase again as we move into the middle and end of
the week in response to two lows moving through the area. The
freezing spray concern has trended down somewhat with the decreased
winds but will start to trend up again as the winds increase. The
strongest winds are expected to continue down Lynn Canal as well as
Stephens Passage and down towards Five Finger lighthouse. With the
first low increasing winds through the Inner Channels. Then the
second low will increase the winds again as a system moves into the
area for the weekend.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Extreme Cold Warning until 6 AM AKST Wednesday for AKZ318.
     High Wind Warning until 9 PM AKST this evening for AKZ318.
     Extreme Cold Warning until noon AKST Wednesday for AKZ319.
     Cold Weather Advisory until 6 PM AKST Wednesday for AKZ320-321-
     323-326-327-329.
     Cold Weather Advisory until 3 PM AKST this afternoon for AKZ322.
     Extreme Cold Warning until 7 PM AKST Wednesday for AKZ325.
     Cold Weather Advisory until 9 AM AKST Wednesday for AKZ328-330-
     332.
MARINE...Heavy Freezing Spray Warning for PKZ011.
     Heavy Freezing Spray Warning for PKZ012-031.
     Heavy Freezing Spray Warning for PKZ013.
     Heavy Freezing Spray Warning for PKZ021.
     Heavy Freezing Spray Warning for PKZ032.
     Heavy Freezing Spray Warning for PKZ032.
     Heavy Freezing Spray Warning for PKZ053.
     Gale Warning for PKZ012-013.
     Small Craft Advisory for PKZ011-021-031>034-036-641>643-661>663.

&&

$$

SHORT TERM...SF
LONG TERM...Contino
AVIATION...DS
MARINE...SF

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