Storm Warning 17, NWS Juneau, AK

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
1011 AM AKDT Tue Sep 16 2025

.UPDATE...Update to the aviation section to include the 18z TAF
issuance.

&&

.SHORT TERM...Main impacts to the short term period will be from a
storm force front moving into the southern gulf Tuesday afternoon
and continuing north along the coastline into Wednesday, bringing
high winds and rain to the panhandle. The previous gale force
system is moving northwest out of the area, with the remnants
keeping higher winds and rain in the southern panhandle. Impacts
will calm down before ramping up again with the next system. The
main changes to the forecast overnight was moving the onset of
impacts back a few hours to match the main low positioning. The
stout front is now expected to reach the southwestern outer coast
of the panhandle Tuesday afternoon, with offshore waters seeing
storm force winds of 48 to 55 knots with peak gusts reaching 60
knots. Winds will funnel into the inner channels as the front
moves through, sending a strong southerly surge of gale force
winds up the panhandle from Tuesday afternoon until Wednesday
evening. These peak speeds will reach the northern parts of the
panhandle Wednesday, forcing southerly gales up Lynn Canal and
easterly gales down Icy Strait and out of Cross Sound. A high wind
watch has been issued for the outer coastal land areas Tuesday
night into early Wednesday morning, so coastal communities can
expect to see strong breezes to near gales (22 to 33 knots), with
unsheltered and elevated areas potentially reaching gales.

Mariners will have a difficult time navigating the channels, as
high winds will be persistent through the period. Significant wave
heights reaching 35 ft in the gulf will increase channel entrance
wave heights to upwards of 17 feet overnight Tuesday into
Wednesday.

Moderate rain is expected with this system, though more systems
behind this one will keep continuous PoPs in the forecast for the
next few days. 24 hour accumulations for Tuesday favor the
northern and central panhandle, with most locations receiving
around half an inch to a little less than an inch of rain.
Wednesday is when a majority of the moisture reaches the
panhandle, with 24 hour totals along the outer coast and interior
of the northern panhandle reaching between 1 to 1.5 inches.
Yakutat and higher elevated areas may see up to 2 inches in 24
hours, while the southern panhandle is only expected to see around
1 inch or less. Cloudy conditions will persist along the front,
allowing potential for blue skies to peak out in the southern
panhandle midday Tuesday. This will allow the southern panhandle's
high temperatures to reach the high 60s into the low 70s, while
cloud cover will keep high temperatures in the upper 50s to low
60s for the northern and central panhandle.

.LONG TERM.../Wednesday Night Toward the End of the Workweek/...
Another storm force low rapidly develops along the front &
quickly pushes northward through the eastern Gulf of Alaska. It
will bring high end gale to storm force winds for the eastern Gulf
on the east side of the low where the pressure gradient will be
the tightest between it & much higher pressure over British
Columbia. It will also bring more moderate to heavy rainfall to
the Panhandle. Since the front will be relatively quickly moving
northwestward through the Panhandle, the heavy rain is not
expected to be prolonged like it has been today for the Ketchikan
area. It will also bring high winds to the southern Panhandle &
Outer Coast & strong winds to other portions of the Panhandle
along with the tightened pressure gradient as the low pushes
northward & nears the coast at different regions of the Panhandle.
High Wind Watches are in effect for the Outer Coast & Annette
Island for the Tuesday night through Wednesday evening timeframe.
See the updates to the Marine Weather Statement & High Wind
Watches for more information.

&&

.AVIATION.../through 18z Wednesday/...
Deteriorating conditions across the northern panhandle and
northeast gulf coast this morning as the band of rain tracks north
out of the southern panhandle. This band will bring MVFR
conditions and periods of low-level wind shear. IFR conditions
can't be ruled out in the steadier rain.

Conditions improve will improve south to north this afternoon as
the band of rain shifts northwest. Then a strong gale to storm
force low will lift north along the coast and will bring MVFR to
even IFR VIS and CIGS by late tonight, along with some very strong
winds and LLWS.

For the southern panhandle, VFR flight conditions prevail with
CIGS AoA 5000ft. Through Tuesday afternoon, aforementioned front
will continue to shift northwest. As it shifts, LLWS and rain
comes to an end through Tuesday morning, with a brief period of
drier weather and clearer skies possible. Tuesday night into early
Wednesday morning, a strong low moves up the eastern Gulf of
Alaska, bringing a resurgence of strong SE-ly LLWS up to 45kts by
6z to 9z Wednesday and flight conditions MVFR or worse. Strongest
LLWS expected Sitka along and eastward to Petersburg and southward
to Ketchikan.

&&

.MARINE...
Outside (Gulf and Coastal waters): A gale force low remains in
the central Gulf this morning bringing winds ranging from moderate
breezes up to near gales at the time of writing. Seas continue to
range between 10-15 ft according to buoys in the Gulf. Winds are
expected to continue to diminish slightly before increasing ahead
of the next system that is expected to move into the area. The
next low moving into the area will bring storm force winds to the
outer coast area while gales will be fairly widespread for the
rest Gulf waters. By the overnight hours tonight, wave heights are
expected to increase from approximately 15 NM to ~100 NM with
wave guidance pointing towards 30 ft waves during the strongest
winds. Areas outside of the storm force winds are still expected
to see 10-17 ft wave heights.

Inside (Inner Channels): Winds across the Inner Channels this
morning remain light for most places with the exception of Young
Bay and Clarence Strait. Throughout today, winds are expected to
increase as the front that moved through the area yesterday moves
to the west. This will bring potentially strong breezes to the
Inner Channels. After this, winds are expected to diminish briefly
before the storm force low in the Gulf moves closer to the outer
coast. As this low moves north, winds are expected to increase to
near gales up to gales tonight. Some areas could see severe gales
as this low moves closer to the coast and inland. Current thinking
would be Cross Sound and Lynn Canal being most likely to
experience severe gales. With the winds coming up along this
system, seas are expected to respond and some places such as Lynn
Canal could see wave heights up to 8 ft while waterways open to
the ocean such as Southern Chatham and Clarence Strait could have
waves up to 12 to 15 ft with larger waves near ocean entrances.

&&

.HYDROLOGY...Rain continues across the area this morning with
the heaviest rain being concentrated across the Central Panhandle
at the moment. Satellite rain rates this morning continue to
report up to a tenth an inch an hour rain. While decent for
accumulations, these amounts are nowhere near in comparison to
reported rainfall totals from around the Ketchikan area yesterday.
As the remnants of the front move across the area today, rain
accumulations for the area will vary by location. For the southern
panhandle, rain accumulations should be limited to between
0.25-0.75" while the central and northern panhandle is looking at
the potential for 0.5- 1" of rain. There is the potential for
higher rainfall amounts for the higher terrain areas. With this
rain, no significant flooding is expected at this time. Heading
into tomorrow, the next area of significant rain moves into the
panhandle bringing anywhere from 0.5" to 2" of rain. The heaviest
rain is expected for the Icy Strait corridor including Juneau
northward to Yakutat. These areas could see 1-2" of rain tomorrow.

Mendenhall Flooding recap: Suicide Basin is no longer releasing
at this time. Peak crest height was observed to be 9.6 ft on
Tuesday at 7:30 PM and is now steadily dropping. Mendenhall River
has fallen below minor flood stage and the flood warning has been
canceled.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Strong Wind from Wednesday morning through Wednesday afternoon
     for AKZ317.
     Strong Wind Wednesday afternoon for AKZ318.
     Strong Wind from Wednesday morning through Wednesday afternoon
     for AKZ319.
     Strong Wind from Wednesday morning through Wednesday afternoon
     for AKZ320.
     High Wind Warning from 10 PM this evening to 7 PM AKDT Wednesday
     for AKZ322-323-327.
     Strong Wind until 4 PM AKDT this afternoon for AKZ323.
     Strong Wind from late tonight through Wednesday afternoon for
     AKZ324.
     Strong Wind from Wednesday morning through Wednesday afternoon
     for AKZ325.
     High Wind Warning from 4 PM this afternoon to 1 PM AKDT
     Wednesday for AKZ328-332.
     Strong Wind from late tonight through Wednesday morning for
     AKZ329.
     Strong Wind from 7 PM AKDT this evening through late tonight for
     AKZ330.
MARINE...Storm Warning for PKZ642>644-662>664-671.
     Gale Warning for PKZ011>013-021-022-031>034-641-651-652-661.
     Small Craft Advisory for PKZ035-036-053-672.

&&

SHORT TERM...ZTK
LONG TERM...JLC
AVIATION...GJS/NM/DS
MARINE...SF
HYDROLOGY...GJS/SF

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