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FXAK67 PAJK 300536 AAA
AFDAJK

Southeast Alaska Forecast Discussion...UPDATED
National Weather Service Juneau AK
936 PM AKDT Wed Jul 29 2026

.UPDATE...Aviation section updated for 6z taf issuance.

&&

SYNOPSIS...

Key Messages:

 - A low pressure system remains over the southern gulf bringing
   showers into the southern and central panhandle.

 - Expect increased marine winds, mainly over the southern gulf
   and Clarence Strait, Thursday into Friday.

 - A ridge builds over the gulf Friday into Saturday allowing for
   winds to weaken and precipitation chances to decrease.

SHORT TERM.../through Friday/...The upper level low has weakened
and evolved into an elongated weak trough over the northern
panhandle as of this discussion. This continues to provide just
enough lift for showers to continue popping up over the area, helped
along by more breaks in cloud cover and daytime heating.
Northeasterly flow over the far northern panhandle and northeast
coast is also allowing some showers that developed over the interior
to cross the border and bring light rain to northern Lynn Canal as
well as over around Yakutat. These showers are still expected to
gradually diminish through the evening Wednesday as upper level
support diminishes. As a result though, some clearing is expected
overnight which will likely lead to more brief patchy fog Thursday
morning, with highest confidence along the northeast gulf coast.

For the southern panhandle, a strengthening low off of Haida Gwaii
will gradually push further northward Thursday, leading to more
widespread rain showers along with increased winds and waves for
Dixon Entrance and southern CLarence Strait, along with southeastern
coastal waters in the gulf. For more information on that, see the
marine discussion below.

With the expected clearing overnight Wednesday for the north, high
temperatures Thursday are expected to be slightly warmer, likely
reaching the low to mid 70s. A ridge advancing across the western
gulf will help to keep the northern panhandle relatively dry with
thinner higher level clouds Thursday and Friday. Two periods of
heavier rain are expected for the southern panhandle as two embedded
shortwaves rotating around the parent low in the southeastern gulf
pass over Thursday morning, and then again Thursday night. Despite
this, overall totals are expected to remain low enough for there to
be no river or stream flooding concerns at this time.

For Friday, as the low starts to slide eastward towards British
Columbia, flow aloft will shift to be more easterly over the
southern and central panhandle. This will be watched closely
Thursday for any potential for isolated thunderstorms that develop
over the interior to potentially advect into the region. Forecaster
confidence was too low to warrant putting them into the official
forecast at this time. For more on what to expect this weekend and
the start of next week, see the long term discussion.

LONG TERM.../Saturday through Wednesday/...
At the start of the long term period a low will be situated over
the southeastern Gulf of Alaska. The associated frontal system
will extend over the southern portions of the panhandle and will
bring light rain showers along the Coastal Range as well as for
communities Petersburg south. While the low will is expected to
remain mostly stationary the strength of which will weaken through
the weekend which will result decreasing rain chances through the
weekend. For the northern panhandle easterly flow will dominate,
and while chances of precipitation is lower compared to areas to
the south, it is non zero. That said, precipitation for the
northern areas is expected to be more showery in nature. Due to
the low weakening the chance of thunderstorms that were mentioned
in the previous forecast discussion seem to becoming less likely.
That said, the thunderstorm chances will have to be monitored
closely as it will be very dependent on the exact track and
strength of the low.

Looking towards the start of the next week, models are in
agreement that a ridge will move into the Eastern Gulf. The exact
amplitude and placement of the ridge axis is still a little bit
uncertain, however it will dictate where the generalized onshore
flow and wetter conditions will be placed. The current line of
thinking is that these conditions will be Icy Bay westward on
Monday and will move east through through mid week.

AVIATION...Areas of clouds still linger across most of the
panhandle this evening though ceilings have remained VFR. Northern
panhandle is showing clearing skies in most areas as easterly flow
increases. With clearing skies, and dewpoints not expected to
substantially fall overnight,expecting at least some fog to
develop, with at least IFR conditions for the aforementioned
areas. While it is possible, did not have the confidence to
introduce LIFR VIS for the northern half TAF sites. Meanwhile
periods of showers continue for the southern panhandle with
periods of MVFR ceilings. Best chance for these conditions is
Thursday midday into the evening.

MARINE...

Outer Waters: The outside waters forecast is dominated by the
seasonably strong low pressure on the southwest portion of Haida
Gwaii, and the associated front moving up from the north. This
front is largely expected to stall over Prince of Wales Island,
generating strong breezes to near gale southeasterlies for the
gulf waters, and up to 20 knots for Clarence Strait through
Thursday, and decaying Thursday night. Due to the longer fetch and
duration, wave heights exceeding 8 ft are likely in the
aforementioned areas. Expecting to see strong wind waves from this
system, not much in terms of swell from far off systems. Going
into the weekend, we look to return to a weaker high pressure
pattern, with broad northwesterlies in the gulf waters.

Inside waters: Mostly benign conditions with winds generally 10
knots or less. Expecting to see a broad switch from
southeasterlies to northerlies tonight as the front approaches the
southern panhandle. Could see some overnight fog development in
areas sheltered from northerly winds, such as parts of Icy Strait
and Stephens Passage. Clarence Strait is expected to stay elevated
for longer, with the possibility of a southerly surge Friday
morning, up to around Frederick Sound.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ641-642-661>663.

&&

$$

SHORT TERM...STJ
LONG TERM...Butwin
AVIATION...NC/EAL
MARINE...NC

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