Petersburg, Alaska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

099
FXAK67 PAJK 052334
AFDAJK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
334 PM AKDT Fri Sep 5 2025

.SHORT TERM...Some precipitation continues moving along the NE
Gulf coast this evening, with Yakutat expecting to get rain this
evening into early tonight, with only some slight chances for rain
and potential for drizzle for the rest of the panhandle. Yakutat`s
PoPs have been increased to around 60% for this evening, with only
about 0.05 to 0.10 inches expected total for tonight`s QPF.
Largely seeing lighter winds and lingering cloud cover into this
evening across the panhandle, with mainly the southern panhandle
beginning to see some clearer skies for tonight. Tomorrow will see
a similar trend with most of the panhandle seeing onshore flow
and cloud cover remaining as the ridge over the central Gulf moves
eastward, while the southern panhandle further from the outer
coastline will see some clearing as offshore flow is promoted by
the ridging offshore. Much like today, temperatures will be lower
due to the cloud cover and lingering moisture, closer to around
normal for this time of year. Some potential for a marine layer
forming tonight into tomorrow morning exists for the outer
coastline as the ridge moves east, with much less of the fog and
visibility restrictions advecting into the inner channels compared
to this morning. The next system begins to approach tomorrow
night, which will begin to bring rain chances for Yakutat and the
NE Gulf coastline into Sunday morning.

.LONG TERM.../Sunday through Friday/ Upper level pattern
continues to show a gradual change from ridging to a more SW flow
pattern over the next week. Of particular note is the strong
upper trough/low that will be moving into the western gulf by the
end of next week. There is still uncertainty on this feature
however as yesterday the consensus was that that feature would be
farther north and west then where it is depicted today. Overall
the main trend through the long range period is cooler, wetter,
and cloudier.

First system of note is still expected to move in for Monday, but
will be fighting the remnants of the ridge over the panhandle as
it comes. No significant winds expected with this feature and any
rain will be light. Most of that precip is expected to be in the
northern half of the panhandle and may only amount to a tenth of
an inch. NE gulf coast likely will get more with upward of around
a quarter inch of rainfall possible. At the very least most areas
can expect an increase in cloud cover as this system moves through
and diminishes over the panhandle.

System number two is the big question mark of the extended as
guidance is having issues pinning down a track as it passes the
Aleutian islands and enters the Western gulf Tue into Thu. There
is consensus that there will be a rather strong system somewhere
near the Aleutian islands, it is just that the track of it
remains up in the air. The main reason for the uncertainty is that
there are tropical remnants associated with the system and over
the last few day the prediction on the track for mid next week has
varied from the central Bering Sea to south of the Aleutians
Island and into the western gulf. The south of the islands
solutions is currently favored and that brings a rather potent
front into the eastern Gulf of Alaska by Thu and Fri. By potent,
we mean gale force, with a low chance of storm force for the
northern gulf, but that is if the current track ends up being the
favored and does not trend back north again. If the track does
trend north again gulf winds will likely be lighter (sub gale
force), but still stronger then what has been seen recently. In
any case, more significant winds as well as rainfall are likely to
be an outcome late next week no matter where the main storm
eventually goes as most solutions today and even yesterday had a
front of some strength and form moving in from the west so expect
an active late week period for the gulf waters and panhandle next
week.

Temperatures throughout the period are expected to show a gradual
downward trend. However these temperatures, even by late next
week, will still be warmer then what is typical for this time of
year. Though they will not be the near record temperatures we saw
a few days ago.

&&

.AVIATION...

Largely improved conditions from this morning but still consistent
IFR/MVFR CIGs across the central inner channels. Luckily for many,
these conditions do look to break out in the next 3 hours for a
brief period of VFR conditions before the sun sets and MVFR to IFR
CIGs come back into the inner channels. Not looking nearly as
intense as last night, as the 925 mb low looks to have disintegrated
and has been replaced by NW flow in the outside waters. Therefore,
CIGs that do develop and move into places like Icy Strait and Sumner
Strait look around MVFR to possibly IFR. Unfortunately for the
outside code, this NW wind means that widespread IFR over the
coastal waters are expected, with the exception of Sitka, nicely
protected by Kruzof Island. Petersburg and Wrangell look to have
some radiation induced fog tonight from consistent dewpoints and
fast dropping temperatures overnight. Not looking for this fog to
possibly late afternoon, but confidence is low.

&&

.MARINE...
Inside Waters: Predominantly lighter winds of less than 10 kt
across the inner channels tonight into tomorrow, with the
exception of southern Clarence Strait and northern Lynn Canal both
seeing some moderate breezes (10-15 kt) this evening and tomorrow
afternoon/evening. Winds will begin to increase moving into Cross
Sound, with moderate breezes expected around Rocky Island tomorrow
evening into tomorrow night as the ridge approaches and tightens
the E-W gradient across Icy Strait. Largely outside of these
areas, and just near the ocean entrances, the inner channels
tomorrow into tomorrow night will remain seeing lighter winds.

Outside Waters: Winds largely remain less than 15 kt tonight into
tomorrow as a ridge begins to push east toward the outer
coastline. This will begin to increase the pressure gradient along
the southern Gulf coast, allowing for some moderate to fresh
breezes (15-20 kt) to the west of POW down towards Haida Gwaii
tomorrow night, which will slowly decrease into the day on
Sunday. Seas predominantly 3-5 ft, with a westerly swell and an 8
to 11 second dominant wave period expected.


&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...None.

&&

$$

SHORT TERM...Contino
LONG TERM...EAL
AVIATION...NC
MARINE...Contino

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