964
FXAK67 PAJK 031401
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
601 AM AKDT Wed Sep 3 2025

.SHORT TERM...
No major changes to ongoing forecast, save for the addition of
adding localized ocean effect winds to some maritime areas
through the day on Wednesday. Overland and inner channel winds
remain largely 10kts or less, although ocean effect winds will
reach up to 15 to 20 kt for some locations through the daytime
hours. Continued ridging aloft has enabled a resurgent marine
layer to push into the southern panhandle, as well as parts of the
outer Coast like Yakutat. Although the marine layer will fall
back during the daytime hours, expect it to return Wednesday night
into Thursday, reaching up from the south into the central
panhandle and the central inner channels.


.LONG TERM...Key Messages:
- High pressure over the gulf continues warm, dry weather
- Temperatures remain above normal through midweek
- Slight cooling over the weekend with increasing clouds and rain
  chances, particularly for northern gulf coast

A blocking ridge and accompanying surface high pressure in the
central gulf will weaken slightly later this week, but still
dominate the overall pattern for southeast Alaska. Warm and dry
summer weather will continue, with the southern panhandle still on
the receiving end of the warmest temperatures, reaching the upper
70s with isolated areas further inland reaching 80 Thursday. Lack
of cloud cover combined with daytime heating will continue to lead
to brisk sea breezes for communities along the inner channels,
with the strongest winds expected in northern Lynn Canal and Taiya
Inlet with thermal troughing developing over the interior. Expect
these to pick up in the afternoon hours to moderate to fresh
breeze consistently through midweek but to a lesser extent
heading into the weekend. This is due to the surface high pressure
weakening slightly in the gulf due to a low moving into the
Alaska Peninsula. This will lead to a further slackening of the
gradient over the central and eastern gulf and thus further
diminishing of winds in that area, as well as seas of 5 ft or
less, mainly driven by a westerly swell pushing into the central
and eastern gulf on Friday.

In terms of rainfall, there is not much to be had due to the
blocking ridge deflecting almost any developing systems away from
our side of the gulf. An upper level trough near in the latter
half of the week will bring light rain chances (up to 30 %) to
the northern gulf coast along with light shower chances to the
outer coast, but the next organized system that has a chance to
properly break us out of the dry and warm pattern continues to be
elusive. For the rain chances this weekend, model ensembles are
trending towards trying to break down this ridge and push a more
persistent trough and surface low into the gulf early next week,
but time will tell.

&&

.AVIATION...For Wednesday morning, the forecasted marine layer
continues it`s expansion, with PAKT reporting CIGS AoB 500 ft as
of 12z. Based off satellite, this layer has enveloped the
majority of fjords spreading from Clarence Strait; certainly
problematic for folks trying to get in and out of Behm Canal and
Misty Fjords. Expect this layer to burn of near 20z Wednesday,
with VFR prevailing into the late afternoon... IFR CIGS from this
stout marine layer form again Wednesday night in similar areas.
There is some indication that this layer will spread further north
Thursday, impacting more of the central Panhandle.

Strongest winds through Wednesday up to and around 15kts and
gusts up to possible 25kts under any sea breeze interactions. No
LLWS concerns through the TAF period.

&&

.MARINE...
Outside: Little change from yesterday. High pressure
continues to control our skies here in SE AK. Swell is out of the
 W in the northern gulf and NW in the southern gulf at 2-3ft
14-18 seconds, with wind waves of 6 to 8 ft less than 10 seconds
along the Prince of Wales (PoW) Coast and Dixon Entrance. These
wind waves are being driven by fresh to strong breezes (17 to 27
knots) out of the NW, highest winds off the coast of PoW and Cape
Fairweather. Wind speeds look to decrease for the second half of
the week as the high pressure weakens.

Inside: Sea breezes continue to be the primary concern for the inner
channels over the next 48 hours. Reported winds speeds have been
getting up to around 10 to 20 kts in the usual trouble spots, Near
Point Couverden, the tighter spots in Stephen`s Passage, and in
Southern Chatham Strait. Winds should calm down during the overnight
and stay lighter into Wednesday morning before picking back up
again for Tuesday afternoon. Wind speeds look to decrease for the
second half of the week as the high pressure weakens.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Heat Advisory until 7 PM AKDT this evening for AKZ319-325-328-
     330-332.
MARINE...Small Craft Advisory for PKZ643-644-661>664.

&&

$$

SHORT TERM...GFS
LONG TERM...STJ
AVIATION...AP
MARINE...GFS

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