Small Craft Advisory 482, NWS Juneau, AK

892 
FZAK51 PAJK 190002
CWFAJK

Coastal Waters Forecast for Southeast Alaska
National Weather Service Juneau AK
402 PM AKDT Mon Oct 18 2021

Southeast Alaska Inside Waters from Dixon Entrance to Skagway

Wind forecasts reflect the predominant speed and direction
expected. Sea forecasts represent the average of the highest
one-third of the combined windwave and swell height.

PKZ098-191715-
402 PM AKDT Mon Oct 18 2021
.SYNOPSIS FOR SOUTHEAST ALASKA INNER CHANNELS COASTAL WATERS...
A high end gale force front over the eastern Gulf will remain 
mostly stationary and begin weakening Tuesday afternoon. The front
will then move NE into the panhandle on Wed and Wed night 
continuing to weaken. Outlook. Another gale force low moves into 
the eastern gulf from the S on Fri. 

$$

PKZ011-191715-
Glacier Bay-
402 PM AKDT Mon Oct 18 2021

.TONIGHT...NW wind 15 kt. Seas 3 ft. 
.TUE...N wind 15 kt. Seas 3 ft. 
.TUE NIGHT...N wind 15 kt. Seas 3 ft. 
.WED...N wind 15 kt. Seas 3 ft. 
.WED NIGHT...NE wind 10 kt. Seas 2 ft or less. Rain.
.THU...SE wind 15 kt becoming N. Seas 3 ft. 
.FRI...N wind 15 kt becoming SE. Seas 3 ft. 
.SAT...SE wind 10 kt becoming light. Seas 2 ft or less. 

$$

PKZ012-191715-
Northern Lynn Canal-
402 PM AKDT Mon Oct 18 2021

.TONIGHT...N wind 15 kt. Seas 3 ft. 
.TUE...N wind 15 kt. Seas 3 ft in the morning then 2 ft or
less. 
.TUE NIGHT...N wind 15 kt. Seas building to 3 ft late. 
.WED...NW wind 15 kt. Seas 3 ft. 
.WED NIGHT...N wind 10 kt. Seas 2 ft or less. Rain.
.THU...N wind 15 kt. Seas 3 ft. 
.FRI...N wind 15 kt becoming SE. Seas 3 ft. 
.SAT...Light winds becoming N 10 kt. Seas 2 ft or less. 

$$

PKZ013-191715-
Southern Lynn Canal-
402 PM AKDT Mon Oct 18 2021

.TONIGHT...N wind 20 kt. Seas 4 ft. Higher gusts near Point
Couverden.
.TUE...N wind 15 kt. Seas 3 ft. Higher gusts near Point Couverden.
.TUE NIGHT...N wind 15 kt. Seas 3 ft. 
.WED...N wind 20 kt. Seas 3 ft. 
.WED NIGHT...NW wind 15 kt. Seas 3 ft. Rain.
.THU...SE wind 15 kt becoming N. Seas 4 ft. 
.FRI...N wind 15 kt becoming SE. Seas 3 ft. 
.SAT...SE wind 10 kt becoming N. Seas 2 ft or less. 

$$

PKZ021-191715-
Icy Strait-
402 PM AKDT Mon Oct 18 2021

...SMALL CRAFT ADVISORY THROUGH TUESDAY...

.TONIGHT...E wind 25 kt. Seas 5 ft. 
.TUE...E wind 25 kt. Seas 5 ft. 
.TUE NIGHT...E wind 20 kt. Seas 4 ft. 
.WED...E wind 20 kt. Seas 4 ft. 
.WED NIGHT...E wind 15 kt. Seas 3 ft. Rain.
.THU...E wind 15 kt. Seas 3 ft. 
.FRI...SE wind 20 kt. Seas 4 ft. 
.SAT...E wind 10 kt. Seas 2 ft or less. 

$$

PKZ022-191715-
Cross Sound-
402 PM AKDT Mon Oct 18 2021

...SMALL CRAFT ADVISORY THROUGH TUESDAY...

.TONIGHT...E wind 30 kt. Seas 12 ft. 
.TUE...E wind 30 kt. Seas 12 ft. 
.TUE NIGHT...E wind 25 kt. Seas 10 ft. 
.WED...E wind 25 kt. Seas 8 ft. Rain.
.WED NIGHT...NE wind 20 kt. Seas 6 ft. 
.THU...E wind 15 kt. Seas 4 ft building to 7 ft. 
.FRI...E wind 25 kt diminishing to 15 kt. Seas 10 ft. 
.SAT...SE wind 15 kt. Seas 9 ft. 

$$

PKZ031-191715-
Stephens Passage-
402 PM AKDT Mon Oct 18 2021

.TONIGHT...N wind increasing to 20 kt in the evening. Seas 4 ft. 
.TUE...N wind 20 kt. Seas 4 ft. 
.TUE NIGHT...N wind 20 kt. Seas 3 ft. 
.WED...N wind 15 kt. Seas 3 ft. 
.WED NIGHT...SE wind 15 kt. Seas 3 ft. Rain.
.THU...NE wind 20 kt. Seas 4 ft. 
.FRI...N wind 25 kt becoming SE. Seas 4 ft. 
.SAT...SE wind 15 kt. Seas 3 ft. 

$$

PKZ032-191715-
Northern Chatham Strait-
402 PM AKDT Mon Oct 18 2021

.TONIGHT...SE wind 20 kt. Seas 4 ft. 
.TUE...S wind 20 kt. Seas 4 ft. 
.TUE NIGHT...N wind 20 kt. Seas 4 ft. 
.WED...NE wind 15 kt. Seas 3 ft. 
.WED NIGHT...SE wind 15 kt. Seas 3 ft. Rain.
.THU...SE wind 10 kt becoming N. Seas building to 3 ft. 
.FRI...NE wind 15 kt becoming SE. Seas 3 ft. 
.SAT...NE wind 10 kt. Seas 3 ft. 

$$

PKZ033-191715-
Southern Chatham Strait-
402 PM AKDT Mon Oct 18 2021

...SMALL CRAFT ADVISORY THROUGH TUESDAY...

.TONIGHT...E wind 25 kt. Gusts to 35 kt. Seas 11 ft, except 16 ft
near ocean entrances. S swell.
.TUE...S wind 25 kt. Gusts to 35 kt. Seas 11 ft, except 16 ft 
near ocean entrances. S swell. 
.TUE NIGHT...E wind 20 kt. Gusts to 35 kt. Seas 8 ft, except 13 
ft near ocean entrances. S swell. 
.WED...E wind 20 kt. Gusts to 30 kt. Seas 8 ft, except
12 ft near ocean entrances. Rain.
.WED NIGHT...SE wind 15 kt. Seas 5 ft. Rain.
.THU...NE wind 20 kt. Seas 6 ft. 
.FRI...NE wind 25 kt becoming S. Seas 9 ft. 
.SAT...NE wind 10 kt. Seas 6 ft. 

$$

PKZ034-191715-
Frederick Sound-
402 PM AKDT Mon Oct 18 2021

.TONIGHT...E wind 15 kt. Seas 3 ft. 
.TUE...E wind 15 kt. Seas 3 ft. 
.TUE NIGHT...E wind 15 kt. Seas 3 ft. 
.WED...E wind 15 kt. Seas 3 ft. 
.WED NIGHT...SE wind 15 kt. Seas 3 ft. Rain.
.THU...NE wind 15 kt. Seas 4 ft. 
.FRI...NE wind 20 kt becoming SE. Seas 4 ft. 
.SAT...SE wind 10 kt. Seas 3 ft. 

$$

PKZ035-191715-
Sumner Strait-
402 PM AKDT Mon Oct 18 2021

...SMALL CRAFT ADVISORY THROUGH TUESDAY...

.TONIGHT...E wind 30 kt. Gusts to 40 kt. Seas 6 ft, except 12 ft
near ocean entrances. 
.TUE...E wind 25 kt. Gusts to 40 kt. Seas 6 ft, except 12 ft
near ocean entrances. 
.TUE NIGHT...E wind 20 kt. Gusts to 35 kt. Seas 5 ft, except
10 ft near ocean entrances. 
.WED...E wind 25 kt. Gusts to 35 kt. Seas 5 ft, except 9 ft near 
ocean entrances. 
.WED NIGHT...SE wind 15 kt. Seas 3 ft. Rain.
.THU...E wind 20 kt. Seas 4 ft. 
.FRI...E wind 30 kt. Seas 6 ft. 
.SAT...E wind 15 kt. Seas 4 ft. 

$$

PKZ036-191715-
Clarence Strait-
402 PM AKDT Mon Oct 18 2021

...SMALL CRAFT ADVISORY THROUGH TUESDAY...

.TONIGHT...SE wind 25 kt. Seas 8 ft. 
.TUE...SE wind 25 kt diminishing in the afternoon. Seas 7 ft. 
.TUE NIGHT...SE wind 20 kt. Seas 5 ft. 
.WED...SE wind 20 kt. Seas 6 ft. Rain.
.WED NIGHT...SE wind 25 kt. Seas 6 ft. Rain.
.THU...SE wind 15 kt increasing to 25 kt. Seas 5 ft. 
.FRI...SE wind 25 kt. Seas 10 ft. 
.SAT...SE wind 15 kt. Seas 6 ft. 

$$

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
602 AM AKDT Mon Oct 18 2021

.SHORT TERM...After an absolutely pleasant weekend for the bulk of
the citizens of SEAK, we will be returning to the cloudy
conditions that are more typical. A ridge of high pressure is
currently in place over the region and is blocking the eastward
advance of a very deep low pressure system in the Gulf. While some
cloud cover will be able to advect overhead, precip will be
limited to coastal areas Monday, and even then PoPs are limited to
the 20s until Monday night. More significant to Monday will be
that the winds will be picking up along coastal areas, mainly
Baranof and POW Islands, as a result of a very strong pressure
gradient around the low. Expected wind gusts in locations such as
Sitka and Hydaburg could be in excess of 40 mph.

Monday night into Tuesday, the ridge holds strong so the low
begins to move a bit north. This should allow for chances for
precip to extend a bit further into the inner channels but really
should not impact areas further east such as Juneau and Ketchikan.
Up to the point of the northward turn, rainfall totals will have
been rather unimpressive, however this movement will direct the
moisture plume directly at Yakutat. While not a great amount by
southeast Alaska standards, rainfall totals around an inch appear
to be plausible from early Tuesday morning through Tuesday night.
The main push of the front eastward really won't be until after
the conclusion of this forecast period, however could potentially
see the beginnings of it happening late Tuesday night as another
low begins moving into the Gulf from the South. The benefit of
this ridge stalling the front out is that it will provide time for
the parent low to weaken, reducing the speed of the winds before
it can push further inland.

Because of the increasing cloud cover, temperatures should be
moderated and there should be a slight warming trend. This will
be particularly noticeable at night as below freezing temperatures
are not anticipated at sea level locations as has been routine
the past couple of evenings.

.LONG TERM.../Wednesday through Sunday/...A fresh round of energy
from the southern Bering Sea splashing east across the Aleutian
Chain into the western Gulf of Alaska should provide sufficient
momentum to push rainfall from the stalled eastern gulf front into
the Panhandle Wednesday. With a strong front stuck in the eastern
gulf for days, the southeasterlies ahead of the system will have
long ago driven out any signs of an early season polar air mass as
850 temperatures largely rise above 0 C. Thus, this precipitation
will fall as rain across Panhandle sea level communities. An
extended breezy period should persist into most of Wednesday, but
as the front pushes in, strength falls markedly, and thus by
Wednesday night winds ease briefly.

With a complex upper low positioned in the Gulf for the
foreseeable future and periodic intrusions of storm inducing
colder air from the Bering and moisture-amping typhoon-fed north
Pacific storms, the pattern becomes ripe for the possibility of a
series of storms riding northward into the southeast gulf. How
strong winds will be, how many storms will arrive, where and when
exactly will they impact are all subject to debate. While this
pattern possesses impactful wind potential, models sadly and
notoriously struggle with specifics for various reasons. Ensembles
tend to agree of the threat of wind from Baranof to the southern
Inner Channels including Prince of Wales, especially the ECMWF
Extreme Forecast Index during this time period, mainly Thursday
through the weekend. We elected to alert partners/public days
ahead with a Special Weather Statement for wind impacting
transportation and causing power outages. Currently we barely
mention gales for the southeast gulf, but this can be ramped up
later as confidence increases. The operational GFS pushes 50 plus
knots of winds at various points late this week. We also
acknowledged the outside chance that one such system (suggested
by the NAM) could develop on Wednesday. But the most likely time
will be Thursday into Sunday. However, the period could last into
early next week.

While not the main focus, the pattern also tends to favor the
highest probability and amounts of rain along the coast and in the
south with much lighter amounts and lower chances in the north.
With the focus of lower pressure deep in the central and
southeastern gulf, winds will largely stay northerly. However,
given warmer temperatures in western Canada, we do not expect
typically strong outflow in response to the storms from the south.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Strong Wind from this afternoon through late tonight for AKZ027.
     Strong Wind from 1 PM AKDT this afternoon through late tonight
     for AKZ023.
MARINE...Gale Warning for PKZ022-041>043-051-052-310.
     Small Craft Advisory for PKZ021-033-035-036-053.

&&

JDR/JWA

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