Small Craft Advisory 475, NWS Juneau, AK

372 
FZAK51 PAJK 140623 AAA
CWFAJK

Coastal Waters Forecast for Southeast Alaska
National Weather Service Juneau AK
321 PM AKDT Wed Oct 13 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.

PKZ098-141530-
321 PM AKDT Wed Oct 13 2021
.SYNOPSIS FOR SOUTHEAST ALASKA INNER CHANNELS COASTAL WATERS...
Lower pressure remains in the northern gulf keeping onshore flow
through late week. Another weak wave of low pressure moves into
the far Southern Panhandle Thursday afternoon. Outlook, an area
of low pressure moves through the southern gulf Friday.  

$$

PKZ011-141530-
Glacier Bay-
321 PM AKDT Wed Oct 13 2021

.TONIGHT...SE wind 20 kt. Gusts to 35 kt in the evening. Seas
4 ft. Rain.
.THU...SE wind 20 kt. Gusts to 35 kt in the morning. Seas
4 ft. Rain.
.THU NIGHT...S wind 15 kt. Seas 3 ft. Rain showers. 
.FRI...S wind 15 kt. Seas 3 ft. 
.FRI NIGHT...N wind 10 kt. Seas 2 ft or less. 
.SAT...N wind 10 kt. Seas 2 ft or less. 
.SUN...N wind 20 kt. Seas 4 ft. 
.MON...SE wind 20 kt. Seas 4 ft. 

$$

PKZ012-141530-
Northern Lynn Canal-
321 PM AKDT Wed Oct 13 2021

...SMALL CRAFT ADVISORY THROUGH THURSDAY...

.TONIGHT...SE wind 20 kt increasing to 30 kt. Gusts to 45 kt.
Seas 4 ft increasing to 6 ft. Rain.
.THU...S wind 25 kt. Seas 5 ft. Rain.
.THU NIGHT...S wind 25 kt decreasing to 20 kt. Seas subsiding to 4
ft. Rain showers.
.FRI...S wind 25 kt. Seas 5 ft. 
.FRI NIGHT...SE wind 10 kt. Seas 2 ft or less. 
.SAT...N wind 25 kt diminishing to 10 kt. Seas 5 ft then 2 ft or 
less. 
.SUN...N wind 15 kt. Seas 3 ft. 
.MON...N wind 15 kt. Seas 3 ft. 

$$

PKZ013-141530-
Southern Lynn Canal-
321 PM AKDT Wed Oct 13 2021

...SMALL CRAFT ADVISORY THROUGH THURSDAY...

.TONIGHT...SE wind 15 kt increasing to 25 kt. Seas building to 5 
ft. Rain.
.THU...S wind 25 kt. Seas 5 ft. Rain.
.THU NIGHT...S wind 25 kt. Seas 5 ft. Rain showers. 
.FRI...S wind 25 kt. Seas 5 ft. 
.FRI NIGHT...SE wind 10 kt. Seas 2 ft or less. 
.SAT...N wind 15 kt. Seas 3 ft. 
.SUN...N wind 20 kt. Seas 4 ft. 
.MON...N wind 25 kt. Seas 5 ft. 

$$

PKZ021-141530-
Icy Strait-
321 PM AKDT Wed Oct 13 2021

.TONIGHT...E wind 15 kt. Seas 3 ft. Rain.
.THU...E wind 15 kt. Seas 3 ft. Rain.
.THU NIGHT...E wind 15 kt. Seas 3 ft. Rain showers. 
.FRI...SE wind 15 kt. Seas 3 ft. 
.FRI NIGHT...E wind 10 kt. Seas 2 ft or less. 
.SAT...NE wind 10 kt. Seas 2 ft or less. 
.SUN...E wind 20 kt. Seas 4 ft. 
.MON...E wind 30 kt. Seas 6 ft. 

$$

PKZ022-141530-
Cross Sound-
321 PM AKDT Wed Oct 13 2021

...SMALL CRAFT ADVISORY THROUGH THURSDAY...

.TONIGHT...W wind 25 kt. Seas 12 ft. Rain.
.THU...SW wind 15 kt. Seas 11 ft. S swell. Rain.
.THU NIGHT...SW wind 15 kt. Seas 10 ft. Rain showers. 
.FRI...SW wind 15 kt. Seas 8 ft. 
.FRI NIGHT...E wind 10 kt. Seas 7 ft. 
.SAT...NE wind 10 kt. Seas 7 ft. 
.SUN...E wind 15 kt increasing to 30 kt. Seas 9 ft. 
.MON...E gale to 35 kt. Seas 10 ft. 

$$

PKZ031-141530-
Stephens Passage-
321 PM AKDT Wed Oct 13 2021

...SMALL CRAFT ADVISORY THROUGH THURSDAY MORNING...

.TONIGHT...S wind 25 kt. Seas 5 ft. Rain.
.THU...SE wind 25 kt decreasing to 15 kt. Seas subsiding to 3 ft.
Rain.
.THU NIGHT...S wind 15 kt. Seas 3 ft. Rain showers. 
.FRI...S wind 15 kt. Seas 3 ft. 
.FRI NIGHT...SE wind 10 kt. Seas 2 ft or less. 
.SAT...Light winds becoming NE 10 kt. Seas 2 ft or less. 
.SUN...NE wind 15 kt becoming SE. Seas 3 ft. 
.MON...SE wind 25 kt. Seas 5 ft. 

$$

PKZ032-141530-
Northern Chatham Strait-
321 PM AKDT Wed Oct 13 2021

.TONIGHT...S wind 20 kt. Seas 4 ft. Rain.
.THU...S wind 20 kt. Gusts to 35 kt in the morning. Seas
4 ft. Rain.
.THU NIGHT...S wind 15 kt. Seas 3 ft. Rain showers. 
.FRI...S wind 15 kt. Seas 3 ft. 
.FRI NIGHT...SE wind 10 kt. Seas 2 ft or less. 
.SAT...Light winds. Seas 2 ft or less. 
.SUN...NE wind 20 kt becoming SE. Seas 4 ft. 
.MON...S wind 30 kt. Seas 6 ft. 

$$

PKZ033-141530-
Southern Chatham Strait-
321 PM AKDT Wed Oct 13 2021

.TONIGHT...S wind 20 kt. Seas 4 ft, except 12 ft near ocean 
entrances. Rain.
.THU...S wind 20 kt. Seas 4 ft, except 11 ft near ocean 
entrances. Rain.
.THU NIGHT...S wind 15 kt. Seas 3 ft, except 10 ft near
ocean entrances. Rain showers. 
.FRI...S wind 15 kt. Seas 3 ft, except 9 ft near ocean
entrances. 
.FRI NIGHT...SE wind 10 kt. Seas 2 ft or less, except 7 ft near 
ocean entrances. 
.SAT...NE wind 10 kt. Seas 2 ft or less. 
.SUN...E wind 15 kt becoming SE 25 kt. Seas 3 ft building to
5 ft. 
.MON...SE gale to 35 kt. Seas 7 ft. 

$$

PKZ034-141530-
Frederick Sound-
321 PM AKDT Wed Oct 13 2021

.TONIGHT...SW wind 20 kt. Gusts to 35 kt. Seas 4 ft. Rain.
.THU...SE wind 20 kt. Seas 4 ft. Rain.
.THU NIGHT...S wind 15 kt. Seas 3 ft. Rain showers.
.FRI...S wind 15 kt. Seas 3 ft. 
.FRI NIGHT...SE wind 10 kt. Seas 2 ft or less. 
.SAT...NE wind 15 kt. Seas 3 ft. 
.SUN...SE wind 15 kt. Seas 3 ft. 
.MON...SE wind 30 kt. Seas 6 ft. 

$$

PKZ035-141530-
Sumner Strait-
321 PM AKDT Wed Oct 13 2021

.TONIGHT...S wind 20 kt. Seas 4 ft, except 8 ft near ocean
entrances. Rain.
.THU...S wind 20 kt. Seas 4 ft, except 8 ft near ocean
entrances. Rain.
.THU NIGHT...SW wind 15 kt. Seas 3 ft, except 8 ft near
ocean entrances. Rain showers. 
.FRI...S wind 15 kt. Seas 3 ft, except 7 ft near ocean entrances.
.FRI NIGHT...SE wind 10 kt. Seas 2 ft or less, except 5 ft
near ocean entrances. 
.SAT...E wind 10 kt. Seas 2 ft or less. 
.SUN...E wind 15 kt. Seas 3 ft. 
.MON...SE wind 30 kt. Seas 6 ft. 

$$

PKZ036-141530-
Clarence Strait-
321 PM AKDT Wed Oct 13 2021

...SMALL CRAFT ADVISORY THURSDAY...

.TONIGHT...S wind 15 kt. Seas 3 ft, except 8 ft near ocean 
entrances. Rain.
.THU...S wind 25 kt. Seas 5 ft, except 9 ft near ocean entrances.
Rain.
.THU NIGHT...S wind 15 kt. Seas 3 ft. Near ocean entrances, seas 
11 ft subsiding to 7 ft late. 
.FRI...S wind 10 kt. Seas 2 ft or less, except 5 ft near ocean
entrances. 
.FRI NIGHT...SE wind 10 kt. Seas 2 ft or less. 
.SAT...SE wind 10 kt. Seas 2 ft or less. 
.SUN...SE wind 15 kt increasing to 25 kt. Seas 3 ft building
to 5 ft. 
.MON...SE gale to 40 kt. Seas 8 ft. 

$$

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
646 AM AKDT Wed Oct 13 2021

.SHORT TERM.../Through Thursday evening/ A southwest flow pattern
persists through the short term period with multiple weak systems
passing through increasing winds and rainfall at times. The first
system to impact the region is currently moving in this morning. A
weak low in the eastern gulf pushes into the NE gulf coast today
while a front traverses the Panhandle. Steady rain this morning
will transition to widespread showers behind the front with the
typical upslope/downslope favored areas receiving more/less
rainfall. Winds are already responding to the front over the
region with Small Crafts to low end Gales through the inner
channels and wind gusts 30 to 40 mph across land areas.

Lower pressure remains in the northern gulf through the period
keeping the southerly gradient over the Panhandle. Winds remain
near or just below small crafts Wednesday evening into Thursday.
Another weak wave of low pressure pushes into the Southern
Panhandle Thursday afternoon increasing winds and rain in that
region. Winds increase to small crafts across the far Southern
Inner Channels; however confidence is low in just how much of a
wind response will come from this wave. Guidance tends to handle
these waves poorly. MOS and hi-res models do indicate an increase
in SE winds across the far south, increasing confidence in a brief
period of breezy conditions Thursday afternoon. Confidence is
highest in the increase in rainfall rates as the wave passes
through. Expect around an inch of rain Thursday with the heaviest
rates Thursday afternoon. Expect both showers and winds to
decrease in coverage and intensity late Thursday across the
Panhandle as the gradient relaxes, higher pressure builds in from
the SE, and onshore flow weakens.

With persistent southerly flow, snow levels will remain high
enough to keep P-type all liquid at sea level. Snow levels will
fall from around 2500 feet to 1500 ft Thursday night as colder air
moves in aloft. Main areas of concern for light accumulating snow
will be along the Klondike Hwy. Potential is there for snow to
mix in with rain in Hyder Thursday morning ahead of the weak wave
as a light E gradient sets up; however confidence is very low on
this.

.LONG TERM.../Friday through Tuesday night/...This extended range
forecast begins with an upper level trough axis situated over the
western Gulf and the core of the upper level jet south of the
Panhandle, crossing the coast between haida Gwaii and Vancouver
Island. The upper trough will deepen and sharpen up as it moves
east, to be over Southeast Alaska Saturday night. An upstream
ridge will shift east to be over Southeast Alaska by Saturday
morning. Upstream of that, a large upper low will enter the Gulf
from the west and be supported by a 170 kt digging jet. The low
itself will trough out and become negatively tilted before it
reaches the outer coast, if it does at all. The very strong upper
jet will actually gain strength and support the development of yet
another sharp upper trough that will be over the western Gulf by
Wednesday morning.

At the surface and near surface, the series of strong lows we have
been experiencing will be in the process of advecting in a cooler
low level airmass. While not cold enough to make snow at the lower
elevations a slam-dunk. While snow at the higher elevations such
as White Pass and near the border on the Haines highway is
obviously more likely, 1000-850mb thicknesses and low level air
temperatures for snow at sea level are still not optimal. While
colder air spills southward this weekend, so does much drier
conditions. Northerly, downsloping flow will keep most of the
precipitation confined to the Southern Panhandle. Current
thinking is that areas that see subfreezing temperatures will
likely have dry conditions and clearing skies rather than snow.
The drying trend will spread north to south through early Sunday
morning with most locations except the southern inner channels
seeing a break from the wet weather.

The break from the excessive wind looks like it will last a little
longer. After some small craft winds over the southern inner
channels Friday night and Saturday, the next big blow doesn't look
like it will enter the eastern Gulf until late Sunday night. At
that time, models are indicating that yet another storm force
front will push east and over the coast on Monday morning with
gales likely over the central and southern inner channels through
Monday night and possibly into Tuesday. There is still some
uncertainty regarding the exact track of the low and associated
front. Due to the colder, drier airmass in place from the weekend,
there is the possibility of precipitation beginning as snow on
the north side of the front early next week. Confidence currently
is low on P-type and the finer details of this system, however
this is definitely a system to keep an eye on.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Strong Wind until 1 PM AKDT this afternoon for AKZ025.
     Winter Weather Advisory until 7 AM AKDT this morning for AKZ018.
     Strong Wind until 7 AM AKDT this morning for AKZ018.
MARINE...Small Craft Advisory for PKZ012-013-022-031>036-041>043-051>053.

&&

CM/Fritsch

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