Juneau, Alaska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

175
FXAK67 PAJK 220002
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
402 PM AKDT Mon Sep 21 2026

.SYNOPSIS...

Key Messages:

- Active weather will continue for the week with low pressures
moving into the Gulf bringing active weather to the area.

- Cooler but seasonable temperatures for the period, with daytime
highs generally in the 50s.

-Potential for a break in the weather Thursday into Friday as high
 pressure moves in temporarily ahead of the next system to affect
 the panhandle.

&&

.SHORT TERM.../through Wednesday night/
Quieter conditions than yesterday, 2 separate weather regimes
hold across the panhandle this afternoon as a weakening low tracks
inland. For the northern panhandle, along and north of a line
from Sitka to Angoon to Five Finger, broad onshore flow continues
through this tonight with scattered showers and isolated
thunderstorms expected. Not expecting widespread thunderstorms
along the coast like yesterday, but can`t rule out a sporadic wind
gust up to 30 kts and locally heavy rainfall in any passing
shower or storm. Further inland, near negligible thunderstorm
threat, but will likely see locally moderate to heavy rainfall
within any passing shower. For the southern panhandle, the
weakening low will continue to track inland through this evening
with locally heavy rainfall amounts up to 0.10 inch per hour and a
very brief period of wind gusts up 30 kts at sea level for
Annette Island and the Ketchikan Gateway Borough. Not
anticipating long lasting elevated winds as winds will be on the
overall decline into the overnight period for a brief lull late
Monday. However as is typical with active SEAK Fall weather,
another low will move into the Gulf with its associated front
pushing across the southern Gulf into the southern panhandle by
Tuesday afternoon. This front will be weaker than previous, and
more typical of this time of year, strongest winds will be
reaching Prince of Wales, Annette Island, and the Ketchikan
Borough area by Tuesday afternoon with gusts up to 30 mph likely.
Forecast rainfall amounts through Wednesday remain around 1 to 2
inches, higher at elevation.

.LONG TERM.../Thursday through Sunday/...
Wednesday will see the tail end of an active weather pattern from
a low pressure system in the gulf, with rain and wind diminishing
through the day. This low is expected to move south out of the
area through the day Thursday, which looks to be a period of drier
conditions and calmer winds. The upper level flow looks to shift
to be more southerly, but not fully offshore, so the southern
panhandle, especially, could see more showery conditions. Late
Friday or overnight into Saturday, another front looks to move
across the panhandle, bringing elevated winds back to the inner
channels, up to about 20-25kts, with periods of heavier rain. This
system is not expected to bring unseasonable amounts of rain, so
there is no major flooding concern at this time.

&&

.AVIATION.../Through 00Z Wednesday/...
Northern areas will see flight categories bounce between MVFR and
VFR with passing showers through this afternoon, with little to
no impact to visibility as showers continue dissipating.
Meanwhile, southern areas are being impacted by a shortwave
tracking northeast toward Canada, bringing reduced conditions with
brief periods of heavy rain and CIGs/VSBY fluctuating between
MVFR and IFR. A lull in activity is expected overnight as rain
becomes lighter, though the brief break between systems will not
allow for a full clear out. Northern sites from Sitka northeast to
Juneau will remain predominantly VFR through the night, although
lingering low clouds cannot be ruled out in the wake of rain
showers. As a low pressure system spins off the coast on Tuesday,
precipitation will be driven onshore through a majority of the
day. Given the convective nature of this next system, rain showers
will be the primary aviation concern, causing rapid drops in CIGs
and VSBY alongside erratic and strong gusts. LLWS is not a
concern at this time with the incoming front tomorrow afternoon,
as flow remains uniform in the lower levels, though mountain top
turbulence is likely.

&&

.MARINE...

Inside(Inner Channels): Winds across the inner channels have
come down quite a bit through Monday afternoon and will continue
to do so through Monday night. Two exceptions will be at opposite
ends of the panhandle, with southerly winds up to 20 kt holding on
a bit longer up near Taiya Inlet, and then a short wave moving
through the southern panhandle bringing some gusty winds through
the early evening hours along with some heavier rain showers.
After tonight, another more organized system will move into the
southern gulf and push another front up through the panhandle
bringing widespread winds up to 25 kt northwards.

Outside (Gulf and Coastal Waters): Winds in the gulf continue to
be 15 to 20 kt or less with the continuing onshore flow pattern
but erratic gusts from heavier convective showers near the
coastline cannot be ruled out. Significant wave heights that
reached as high as 10 to 13 ft across the gulf will continue to
subside north of Cape Edgecumbe before building once more with the
approach of the next system. Winds of 25 to 30 kt are anticipated
with the Tuesday front and along with seas building up to 10 to 15
ft, with highest seas expected in the southeast gulf. This low
will bring in some more partially unstable air, so there is a
chance for more scattered thunderstorms to develop Tuesday and
Tuesday night.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ021-022-032>036-053-641>644-651-652-
     661>664-671-672.

&&

$$

SHORT TERM...NM
LONG TERM...AGP
AVIATION...BAS
MARINE...STJ

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