Small Craft Advisory 42, NWS Juneau, AK

651 
FZAK51 PAJK 180007
CWFAJK

Coastal Waters Forecast for Southeast Alaska
National Weather Service Juneau AK
307 PM AKST Sun Jan 17 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.

PKZ098-181530-
307 PM AKST Sun Jan 17 2021
.SYNOPSIS FOR SOUTHEAST ALASKA INNER CHANNELS COASTAL WATERS...
A ridge of high pressure across the Inner Channels shifts E into
western Canada Sun night. A storm force front enters the central 
gulf late Sun night and reaches SE Alaska Mon afternoon. Another 
ridge of high pressure develops across the Inner Channels Mon 
night and persists through Tue. 

$$

PKZ011-181530-
Glacier Bay-
307 PM AKST Sun Jan 17 2021

...SMALL CRAFT ADVISORY MONDAY...

.TONIGHT...SE wind 15 kt diminishing. Seas 3 ft in the evening 
then 2 ft or less. 
.MON...SE wind 15 kt increasing to 25 kt in the afternoon.
Seas 4 ft. Rain.
.MON NIGHT...S wind 20 kt. Seas 5 ft. Rain.
.TUE...S wind 20 kt. Seas 4 ft. 
.TUE NIGHT...W wind 10 kt. Seas 2 ft or less. 
.WED...NW wind 10 kt. Seas 2 ft or less. 
.THU...N wind 10 kt. Seas 2 ft or less. 
.FRI...Light winds. Seas 2 ft or less. 

$$

PKZ012-181530-
Northern Lynn Canal-
307 PM AKST Sun Jan 17 2021

...GALE WARNING MONDAY...

.TONIGHT...S wind 30 kt diminishing to 15 kt late. Seas 6 ft 
subsiding to 3 ft late. 
.MON...S wind 20 kt becoming SE 35 kt in the afternoon. Seas
4 ft building to 7 ft in the afternoon. Rain.
.MON NIGHT...SE gale to 35 kt. Seas 7 ft. Rain.
.TUE...SE wind 30 kt. Gusts to 45 kt. Seas 6 ft. Rain
showers. 
.TUE NIGHT...S wind 25 kt. Gusts to 40 kt. Seas 5 ft. 
.WED...S wind 10 kt becoming N. Seas 2 ft or less. 
.THU...NW wind 15 kt. Seas 3 ft. 
.FRI...NW wind 10 kt. Seas 2 ft or less. 

$$

PKZ013-181530-
Southern Lynn Canal-
307 PM AKST Sun Jan 17 2021

...GALE WARNING MONDAY...

.TONIGHT...S wind 25 kt becoming SE 15 kt late. Seas 5 ft 
subsiding to 3 ft late. 
.MON...SE wind 20 kt increasing to 35 kt in the afternoon. Seas 4
ft building to 7 ft in the afternoon. Rain.
.MON NIGHT...SE gale to 35 kt becoming S 25 kt late. Seas 6 ft. 
Rain.
.TUE...S wind 25 kt. Seas 5 ft. Rain showers. 
.TUE NIGHT...S wind 25 kt. Seas 5 ft. Rain showers. 
.WED...S wind 10 kt becoming N. Seas 2 ft or less. 
.THU...N wind 10 kt. Seas 2 ft or less. 
.FRI...N wind 10 kt becoming light. Seas 2 ft or less. 

$$

PKZ021-181530-
Icy Strait-
307 PM AKST Sun Jan 17 2021

...SMALL CRAFT ADVISORY MONDAY...

.TONIGHT...SE wind 20 kt. Seas 4 ft. 
.MON...E wind 20 kt becoming SE 30 kt in the afternoon. Seas
5 ft. Rain.
.MON NIGHT...S wind 25 kt. Seas 5 ft. Rain.
.TUE...SW wind 30 kt. Seas 6 ft. 
.TUE NIGHT...W wind 20 kt. Seas 4 ft. 
.WED...W wind 10 kt. Seas 3 ft. 
.THU...W wind 10 kt. Seas 2 ft or less. 
.FRI...E wind 10 kt becoming light. Seas 2 ft or less. 

$$

PKZ022-181530-
Cross Sound-
307 PM AKST Sun Jan 17 2021

...SMALL CRAFT ADVISORY THROUGH MONDAY...

.TONIGHT...SW wind 30 kt diminishing to 20 kt, then becoming E 
late. Seas 13 ft. S swell.
.MON...E wind 30 kt. Seas 14 ft. Rain.
.MON NIGHT...SW wind 30 kt. Seas 18 ft. Rain.
.TUE...W gale to 35 kt. Seas 19 ft. Rain showers. 
.TUE NIGHT...W wind 25 kt. Seas 16 ft. S swell. Rain showers.
.WED...W wind 15 kt. Seas 12 ft. 
.THU...W wind 15 kt. Seas 10 ft. 
.FRI...E wind 10 kt. Seas 8 ft. 

$$

PKZ031-181530-
Stephens Passage-
307 PM AKST Sun Jan 17 2021

...GALE WARNING MONDAY...

.TONIGHT...SE wind 20 kt. Seas 5 ft. 
.MON...SE wind 35 kt. Seas 7 ft. Rain.
.MON NIGHT...SE gale to 35 kt becoming S 20 kt late. Seas 7 ft 
subsiding to 4 ft late. Rain.
.TUE...S wind 20 kt. Seas 4 ft. Rain showers. 
.TUE NIGHT...S wind 15 kt. Seas 3 ft. 
.WED...S wind 15 kt becoming N. Seas 3 ft. 
.THU...N wind 10 kt. Seas 2 ft or less. 
.FRI...SE wind 10 kt. Seas 2 ft or less. 

$$

PKZ032-181530-
Northern Chatham Strait-
307 PM AKST Sun Jan 17 2021

...GALE WARNING MONDAY...

.TONIGHT...S wind 15 kt. Seas 3 ft. 
.MON...SE wind 35 kt. Seas 7 ft. Rain.
.MON NIGHT...S gale to 35 kt diminishing to 20 kt late. Seas
7 ft subsiding to 4 ft late. Rain.
.TUE...SW wind 15 kt. Seas 3 ft. 
.TUE NIGHT...S wind 15 kt. Seas 3 ft. 
.WED...S wind 15 kt becoming N. Seas 3 ft. 
.THU...N wind 10 kt. Seas 2 ft or less. 
.FRI...Light winds. Seas 2 ft or less. 

$$

PKZ033-181530-
Southern Chatham Strait-
307 PM AKST Sun Jan 17 2021

...GALE WARNING MONDAY...

.TONIGHT...S wind 15 kt. Seas 4 ft, except 14 ft near ocean
entrances. 
.MON...SE wind 30 kt becoming S 40 kt in the afternoon. Seas
7 ft. Near ocean entrances, seas 12 ft building to 16 ft in the
afternoon. Rain.
.MON NIGHT...S gale to 35 kt becoming SW 20 kt late. Seas 7 ft
subsiding to 4 ft late. Near ocean entrances, seas 18 ft. Rain.
.TUE...SW wind 20 kt. Seas 4 ft, except 18 ft near ocean
entrances. 
.TUE NIGHT...SW wind 15 kt. Seas 3 ft, except 15 ft near
ocean entrances. 
.WED...SW wind 15 kt becoming NW. Seas 3 ft. 
.THU...NW wind 10 kt. Seas 2 ft or less. 
.FRI...E wind 10 kt becoming light. Seas 2 ft or less. 

$$

PKZ034-181530-
Frederick Sound-
307 PM AKST Sun Jan 17 2021

...GALE WARNING MONDAY...

.TONIGHT...SE wind 15 kt. Seas 4 ft. 
.MON...SE wind 25 kt increasing to 35 kt in the afternoon.
Seas 6 ft. Rain.
.MON NIGHT...SE gale to 35 kt becoming S 20 kt late. Seas 7 ft
subsiding to 4 ft late. Rain.
.TUE...SW wind 20 kt. Seas 4 ft. 
.TUE NIGHT...S wind 15 kt. Seas 3 ft. 
.WED...S wind 15 kt becoming light. Seas 3 ft. 
.THU...NW wind 10 kt. Seas 2 ft or less. 
.FRI...SE wind 10 kt. Seas 2 ft or less. 

$$

PKZ035-181530-
Sumner Strait-
307 PM AKST Sun Jan 17 2021

...GALE WARNING MONDAY...

.TONIGHT...S wind 10 kt. Seas 3 ft, except 8 ft near ocean
entrances. 
.MON...SE wind 25 kt increasing to 35 kt in the afternoon.
Seas 6 ft. Rain in the afternoon. 
.MON NIGHT...SE gale to 35 kt becoming SW 20 kt late. Seas
7 ft subsiding to 4 ft late. Near ocean entrances, seas 11 ft.
Rain.
.TUE...SW wind 20 kt. Seas 4 ft, except 10 ft near ocean
entrances. 
.TUE NIGHT...SW wind 15 kt. Seas 3 ft, except 8 ft near ocean
entrances. 
.WED...W wind 15 kt becoming N. Seas 3 ft. 
.THU...NE wind 10 kt. Seas 2 ft or less. 
.FRI...NE wind 10 kt becoming light. Seas 2 ft or less. 

$$

PKZ036-181530-
Clarence Strait-
307 PM AKST Sun Jan 17 2021

...GALE WARNING MONDAY...

.TONIGHT...SE wind 15 kt. Seas 3 ft, except 7 ft near ocean
entrances. 
.MON...SE wind 25 kt increasing to 35 kt in the afternoon.
Seas 5 ft building to 8 ft in the afternoon. Rain in the
afternoon. 
.MON NIGHT...S gale to 35 kt. Seas 12 ft, except 14 ft near
ocean entrances. Rain.
.TUE...SW wind 15 kt. Seas 6 ft, except 10 ft near ocean
entrances. 
.TUE NIGHT...NW wind 15 kt. Seas 3 ft, except 7 ft near ocean
entrances. 
.WED...NW wind 15 kt. Seas 3 ft. 
.THU...N wind 15 kt. Seas building to 3 ft. 
.FRI...N wind 15 kt becoming SE. Seas 3 ft. 

$$

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
305 PM AKST Sat Jan 16 2021

.SHORT TERM.../Through Monday night/The short term forecast
remains much of the same. We are on the second half of the most
recent storm force front with another (weaker) front expected
Sunday. Then a strong low will move into the gulf. This will
bring more storm force winds to the coast and high winds over
parts of the northern Panhandle late Sunday night into Monday.

The storm force winds along the coast from today will calm down
tonight. That being said, strong winds are still expected in open
waters. So, gale warnings come to end this evening but small
craft advisories last through the night.

Then tomorrow's front will keep the small crafts in place over
coastal waters and should kick the winds up in Lynn Canal so a
small craft advisory will go into effect Sunday morning.

Winds weaken late Sunday and Sunday night but they'll pick right
back up as that strong low moves into the gulf and pushes a strong
weather front into the panhandle early in the work week. By
Monday morning, open water winds will be around 40 to 50 knots
with winds in the inner channels getting up to 35 knots in the
afternoon.

Because of Monday's front, a High Wind Watch will be issued for
the northeast and east gulf coast and for parts of the central
inner channels due to possible high winds. This will be in effect
beginning Monday morning.

The parade of fronts and lows will keep a general south to
southwest flow over the panhandle so temps should stay above
normal with highs in the upper 30s to 40s and lows mostly in the
mid to upper 30s.

And this parade of fronts and lows will keep at least a chance of precip
in place over the panhandle through Monday night. But expected temps
should support rain for most of the panhandle.

That being said, there is a small area where temperatures could
cool down enough to support snow. So because of this, a Winter
Storm Watch will be issued for the far northeastern corner of the
northern inner channel. This will be in effect beginning Monday
morning.

Forecaster confidence in this forecast has been growing. The High
Wind forecast confidence is highest for Yakutat with moderate to
average forecast confidence for the rest. The Winter Storm
forecast confidence is moderate.

.LONG TERM.../Monday through Saturday as of 10 pm Friday/ Pattern
change in the works as we head through next week. Initially we
will still be stuck in an active SW flow pattern aloft with at
least one more storm system moving through the area in the first
part of the long range. That gradually changes mid week into late
week as more ridging begins to show up over most of the Gulf of
Alaska and Central Alaska. However, this ridging is not strong
enough to be a blocking pattern as at least one storm will be
trying to push through the ridge and into the panhandle next
weekend. Depiction of the SW flow and the initial ridge mid next
week has fairly average forecast confidence, but that confidence
falls to low toward late week and next weekend as long range
guidance has trouble figuring out how strong system trying to
break through the ridge will play out and if it will make the
panhandle or not.

At the surface, the first part of the long range remains fairly
active with a wet storm-force front moving through the area Mon
into Mon night. IVT and PW anomalies continue to indicate a
fairly decent atmospheric river connection with this front.
Fortunately, the front does not linger over the area very long so
we are looking at around 1 to 3 inches of QPF over any given area
through Mon night right now. Still there will be periods of
moderate to even heavy rain at times for most of the panhandle.
Most areas will be warm enough for rain, but the Haines and
Klondike highways may see some snow (possibly several inches worth
near White Pass). Winds will be the other concern, but with the
parent low so far W, the front will be weakening as it moves E.
Storm force winds are expected for the northern gulf while gales
(Marine areas) and gusty winds 40 to 55 mph (land areas) are
expected elsewhere.

The forecast quiets down for Tues onward as the ridging aloft
begins to develop. Some fairly weak system will still try to
advance on the panhandle through the period, but they do not have
the strength that previous systems have had. There is also more
forecast uncertainty showing up from Wed onward as guidance tries
to figure out what to do with the developing ridge. Overall trends
point toward a drier forecast with the possibility of some cold
air working southeastward Thu into Fri. The cold air is somewhat
uncertain as the Canadian is being rather aggressive with it
while the ECMWF is not as aggressive and the GFS is has it barely
there at all. We will continue to monitor how this pattern change
develops.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Strong Wind until 6 PM AKST this evening for AKZ025>028.
     High Wind Watch from Monday morning through Monday evening for
     AKZ017-022-023-025.
     Winter Storm Watch from Monday morning through Tuesday morning
     for AKZ018.
MARINE...Storm Warning for PKZ043-051-052.
     Gale Warning for PKZ036-041-042.
     Small Craft Advisory for PKZ021-022-031-033>035-053.

&&

GJS/EAL

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