Area Forecast Discussion
Issued by NWS Juneau, AK

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FXAK67 PAJK 170601 AAA
AFDAJK

Southeast Alaska Forecast Discussion...UPDATED
National Weather Service Juneau AK
1001 PM AKDT Sat Aug 16 2025

...Evening and 06z Aviation Discussion Update...
Minor changes to on-going forecast as occluding low continues to
meander northward along the eastern Gulf of Alaska. Main change is
increasing winds across the southern panhandle as low departs,
particular for Prince of Wales Island, Clarence Strait, over to
the Ketchikan Gateway Borough and Metlakatla with sustained marine
winds around 10 to 20kts and overland winds up to 25mph through
early Sunday morning. Overall, brief increase in winds across the
panhandle overnight as front pushes through the area, but not
anticipating any widespread impacts or strong winds. For the rest
of tonight, rain will continue over overcast skies with lows
dropping into the low 50s to upper 40s.

&&

.SHORT TERM...
A broad occluded low will continue to move northward along the
panhandle late today and into Sunday, bringing widespread light
to isolated moderate showers. These showers will continue into
Sunday, though decreasing in coverage and intensity for the
southern panhandle as the low center tracks towards Kruzof Island
before turning more westward. For the northern panhandle, showers
will spread further northward, though rain totals are expected to
remain low as the system continues to gradually weaken. The broad
wind field from this system however will lead to wind shear
across many TAF sites in the panhandle and south winds across the
inner channels, with winds up to strong breeze (22 to 27 knots)
moving from Clarence Strait northward through Saturday evening
with some gusts up to 25 knots possible, reaching southern
Stephens Passage late tonight into Sunday morning. On Sunday, the
low center will continue to propagate westward before rotating
southward out into the gulf, weakening further and allowing winds
across the inner channels to relax down to gentle or moderate
breeze (7 to 16 knots). Extensive cloud cover and light
precipitation will generally offset any potential warming from the
southerly flow at the surface, with daytime highs remaining
seasonable at the low to mid 60s, exception being Haines and
Skagway which could be a bit warmer and drier due to downsloping
winds Saturday before showers make it into that area.

Despite this low weakening and moving back out into the gulf,
interaction of northeasterly flow aloft with a low pressure
system over the Canadian interior will lead to some continues
shower activity for the northern panhandle into Monday. For more
information on this and what to expect later next week, see long
term discussion

.LONG TERM...
Key Messages:
-Overall drying trend next week with warmer temps likely for the later
 half of the week.

-Lingering low pressure will keep some chances for light rain in
 the forecast through the first part of the work week.

-A building ridge of high pressure will bring drier weather and
 warmer temps for the later part of next week into next weekend.

-Marine wind speeds look to be on the lighter side next week at
 around 5 to 10 knots with some isolated trouble spots getting up
 to 15 knots.

Discussion:
An area of low pressure will spin and linger in the gulf early
next week. This low will bring some onshore flow, meaning some
low-end chances for rain and rain showers will remain in the
forecast early next week. That being said, those that see any rain
will see mainly light rain with 24 hour rainfall amounts at around
0.25 inches or less for Monday and Tuesday. Wednesday`s 24 hour
amounts are even lighter.

After the lingering low finally moves on and out of the area mid-
week, a potential ridge of high pressure looks to move in. This
would bring decreasing rain chances and decreasing cloud cover. So
sunnier skies are looking likely later next week. With sunnier
skies comes warmer temps, with highs warming to the upper 60s to
the near 70 for Thursday into next weekend.

A broad brush look at the marine wind speeds is looking quiet with
wind speeds looking to be around 5 to 10 knots with the usual
trouble spots potentially getting up to 15 knots. So overall, not
too bad for late August.

&&

.AVIATION.../through 06z Monday/
Predominate MVFR to IFR flight conditions across the central and
southern panhandle with CIG AoB 2500ft and visibilities down to 2
to 4 within heavier showers as a low pressure system continues to
traverse up the eastern Gulf of Alaska. Across the northern
panhandle, Icy Strait northward, seeing general VFR conditions
with upper level OVC ceilings around 8000ft. Through tonight,
anticipating decrease in flight conditions to MVFR or worse across
the panhandle with widespread CIGS AoB 3000ft and rain chances
continuing, resulting lowered IFR visbys as low as 2SM. Rain
chances decrease through Sunday, with widespread precipitation
becoming more isolated by 00z Monday. For Sunday, general MVFR to
low-end VFR conditions will prevail by the afternoon with CIGS AoB
4000ft with visbys 4 to 6SM, down to 2SM within heaviest showers.


Low-end LLWS will gradually come to an end through 12z as low
continues to weaken. Winds through tonight should remain around
10kts or less, with isolated gusts up to 20kts possible, going
calm and variable at wind sheltered locations.


&&

.MARINE...
Synopsis: A weakening low pushes northwestward through the
eastern Gulf of Alaska, sending periods of showers and gusty
winds into the Inner Channels through the latter half of the
weekend.

Inside Waters: Winds up to strong breeze (22 to 27 knots) moving
from Clarence Strait northward through tonight with some gusts up
to 25 knots possible, reaching southern Stephens Passage Sunday
morning. On Sunday, the low center will continue to propagate
westward before rotating southward out into the Gulf of Alaska,
weakening further and allowing winds across the inner channels to
relax down to gentle or moderate breeze (7 to 16 knots) late Sunday.

Outside Waters: For tonight, Small Craft Advisories are posted for
winds increasing to 25 kts and seas around 10 ft from Dixon
Entrance north to Cape Decision offshore about 50 nm, where the
tighter pressure gradient is on the east side of the main area of
low pressure. As the main area of low pressure moves to the
northwest across the eastern Gulf, we do expect to see the areas
of tighter pressure gradient shifting north from Cape Decision
to Icy Cape and out 85 nautical miles through Sunday...with winds
at times 25 to 30 kts sustained. As the low pressure system
weakens, we expect winds and seas to diminish over the eastern
Gulf by Monday.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Small Craft Advisory for PKZ033-035-036-641>644-651-661>663.

&&

$$

SHORT TERM...STJ
LONG TERM...GJS
AVIATION...NM
MARINE...JG

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