Petersburg, Alaska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

925
FXAK67 PAJK 060053
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
353 PM AKST Fri Dec 5 2025

.SYNOPSIS...

Key Messages:

 - Low pressure system in the Gulf brings front eastward across
   the panhandle Friday evening through Saturday, bringing
   moderate to heavy snow to the northern panhandle and moderate
   to heavy rain for the southern panhandle.

 - This weekend through next week, models continue falling into
   line behind a weather pattern that has been known to produce
   heavy snow. Higher confidence in totals for the northern
   panhandle, but still some uncertainty remains about timing and
   amounts as cold air pushes southward.


&&

.SHORT TERM...The main changes made to the short term forecast
today were to narrow down precipitation timing and amounts for
the incoming system.

A low pressure system has advanced into the north central gulf,
sending a front into the northern panhandle before spreading
southeast through Friday night. This front is expected to bring
moderate to heavy rain rates with increasing wind speeds
overnight. Looking at half an inch to an inch of rain for the
northern panhandle Friday night, largely spreading to the rest of
the panhandle through Saturday morning and bringing around another
inch to an inch and a half Saturday. The system is reinforced
through Saturday and continues to stall in the gulf into the
extended period, continuing to funnel consistent moisture and
strong winds into the panhandle. An area of deep upper level
troughing is beginning to shift over the panhandle, bringing
colder temperatures and increasing outflow winds through the
weekend and into next week. These cold temperatures steadily move
southward through this period, and in combination with the
abundance of available moisture, precipitation will begin to
transition into snow.

Communities in the far northern panhandle are starting to see
this transition tonight, with Skagway already reporting light snow
beginning to fall. A winter storm warning was issued for heavy
snow accumulation in Skagway and Haines through Sunday, with the
greatest accumulations and heaviest rates expected to fall on the
higher elevations of the Klondike and Haines Highways. Consistent
moderate to heavy snowfall is looking to bring accumulations of
between 18 and 28 inches to Skagway and 15 to 22 inches to the
Haines Borough, with the higher amounts expected at higher
elevations of the highways. For Skagway at sea level and along the
highway, and from Haines down along the Chilkat Peninsula, wind
gusts up to 45 mph are possible Sunday which may result in some
blowing snow following the fresh snowfall. Yakutat is also
expected to dip below freezing temperatures overnight and begin
accumulating advisory level snowfall of around 3 to 5 inches
through Saturday. Confidence has increased that the Icy Strait
Corridor, including the cities of Gustavus, Hoonah, Tenakee
Springs, Elfin Cove, Pelican, and Juneau, may see significant
snowfall accumulations starting Sunday. A watch has been issued
for potentially heavy snow from Sunday morning into Monday night,
with accumulations between 11 to 16 inches possible. Cold
temperatures continue to drop southward into the central panhandle
as another system advances from the south, sending another front
with similar rain rates into the southern panhandle. The pattern
continues to persist through the long term, increasing confidence
of a long duration snow and rain event. See the long term for more
information on how this pattern will continue into next week.

.LONG TERM.../ Sunday to Tuesday / The arctic boundary continues
to move southward with the northerly outflow trying to set up.
Expect snow to develop Sunday from Pelican-Elfin Cove east
towards Juneau ( the Icy Strait Corridor) and continue through
much of Monday to Tuesday. Significant snowfall may fall Sunday to
Monday evening, so a watch has been issued.

Cold air will continue to push south Tuesday, and spread the snow
into the southern panhandle by Tuesday.

Gusty north winds from the outflow, with gusty winds to 40 to 45
mph perhaps so possibly blowing snow, if snow characteristics are
right, or freezing spray down Lynn Canal.

&&

.AVIATION.../Until 00Z Sunday/...As far as CIGs & VISs are
concerned, for the northern 2/3 of the panhandle, flight conditions
are generally expected to be in the MVFR/IFR category range through
the period as a weather system will be pushing through. Under
heavier precipitation, periodically, conditions may lower to within
the LIFR category. For the remainder of the panhandle, aside from
some FG around the PAPG/PAWG area this afternoon/evening, limiting
VISs to the LIFR category, conditions will start in the VFR category
& deteriorate/lower to well within the MVFR flight category late
this evening/overnight & stay that way through the end of the 24-
hour TAF period. SFC winds will become gusty late this
evening/overnight & remain that way through the end of the period
for the northern 2/3 of the panhandle. SFC winds elsewhere will
remain relatively on the lighter side through the period. A
combination of directional with variation between easterly for the
NE Gulf Coast, including PAYA, & southerly to southwesterly
elsewhere & speed shear centered aloft at between 1.5 & 2 kft of up
to around 35 kt in magnitude is expected starting late this evening
as the weather system approaches & pushes into Southeast Alaska.

&&

.MARINE...
Outside Waters: Lighter conditions will continue across the gulf
from a ridge moving through Friday. This will quickly be displaced
by an oncoming system from the west Friday night into Saturday.
Winds will shift south southwesterly and increase to fresh to
strong breeze (17 to 27 kt) by early Saturday. These stronger
winds will last through Saturday and As the pressure gradient
tightens between the low in the Gulf and the high to the north
over Canada Saturday night into Sunday, northeasterly near gale to
gale force (30 to 40 kt) offshore winds and gap winds will occur
along the NE Gulf Coast between Yakutat Bay and Cape Spencer. The
southeastern Gulf will also see an increase from near gales to
gales (28 to 36 kt) as a front moves through Saturday night into
Sunday morning and again Sunday night into Monday. Seas between 5
and 8 ft will quickly increase tonight into Saturday as the system
moves in to between 10 and 14 ft. The seas will continue to see
an increase into Sunday to 12 to 16 ft. Southwesterly swell
continues tonight through the weekend.

Inside Waters: Lingering fog and low stratus continues to plague
parts of the inner channels Friday afternoon, particularly along
Icy Strait as well as Frederick Sound in the vicinity of
Petersburg. Calmer surface conditions that allowed for this fog
development will give way to a sharp increase Friday night into
Saturday as the next system moves into the area. This will bring
southeasterly winds across the inner channels between a moderate
to fresh breeze (11 to 21 kt) into Saturday, and up to a strong
breeze (22 to 27 kt) for northern Lynn, Frederick Sound, Stephens
Passage, and near the ocean entrances. The channels will see a
brief increase as the fronts move across the panhandle this
weekend into early next week. Northerly outflow begins to set up
over northern Lynn Sunday as the pressure gradient begins to
tighten, bringing near gales in the morning becoming gales into
the day Sunday. Largely expecting between 35 and 43 kt winds down
Lynn Canal lasting from Sunday into early next week, with the
stronger northerlies moving southward down to Point Couverden
Sunday night into Monday. This will allow some lower level
convergence right around Point Couverden from the southeasterly
winds up Chatham Strait and the northerly outflow coming down out
of Lynn Canal, bringing winds around Rocky Island to around 25 to
30 kt. Frederick Sound near Point Fanshaw and up along Stephens
Passage will continue to see strong breezes to near gales
throughout the weekend, alongside Clarence Strait seeing near
gales as the fronts move through and bring stronger southeasterly
winds.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Weather Advisory from 3 AM to 9 PM AKST Saturday for
     AKZ317.
     Winter Storm Warning from 10 PM this evening to 3 PM AKST Sunday
     for AKZ318.
     Winter Storm Warning from 3 AM Saturday to 3 PM AKST Sunday for
     AKZ319.
     Winter Storm Watch from Sunday morning through Monday afternoon
     for AKZ320>322-325.
MARINE...Gale Warning for PKZ652.
     Small Craft Advisory for PKZ012-013-022-031-034-053-641>644-651-
     661>664-671-672.

&&

$$

SHORT TERM...ZTK/Contino
LONG TERM...Bezenek
AVIATION...JLC
MARINE...STJ

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