Gale Warning 132, NWS Juneau, AK

982 
FZAK52 PAJK 072336
CWFAEG

Coastal Waters Forecast for Southeast Alaska
National Weather Service Juneau AK
336 PM AKDT Wed Apr 7 2021

Southeast Alaska Coastal Waters from Dixon Entrance to
Cape Suckling out 100 NM

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

PKZ099-081745-
336 PM AKDT Wed Apr 7 2021
.SYNOPSIS FOR OUTSIDE WATERS...
A storm force low and front will move into the AK Gulf Thu. The
front will move E across the Panhandle Thu while the low lingers
in the NE gulf through Fri.  

$$

PKZ041-081745-
Dixon Entrance to Cape Decision-
336 PM AKDT Wed Apr 7 2021

...GALE WARNING THURSDAY...

.TONIGHT...NW wind 25 kt becoming W 15 kt late. Seas 10 ft. 
.THU...S wind 40 kt. Seas 15 ft. Rain.
.THU NIGHT...SW wind 30 kt. Seas 19 ft. Rain.
.FRI...W wind 30 kt. Seas 18 ft. 
.FRI NIGHT...NW wind 30 kt. Seas 18 ft. 
.SAT...W wind 20 kt. Seas 14 ft subsiding to 10 ft. 
.SUN...S wind 20 kt. Seas 13 ft. 
.MON...S wind 25 kt. Seas 10 ft. 

$$

PKZ042-081745-
Cape Decision to Cape Edgecumbe-
336 PM AKDT Wed Apr 7 2021

...GALE WARNING THURSDAY...

.TONIGHT...W wind 20 kt. Seas 10 ft. 
.THU...S wind 35 kt. Seas 17 ft. Rain.
.THU NIGHT...W gale to 35 kt. Seas 22 ft. Rain.
.FRI...W wind 25 kt. Seas 19 ft. W swell. 
.FRI NIGHT...NW wind 25 kt. Seas 17 ft. W swell. 
.SAT...SW wind 15 kt. Seas 13 ft subsiding to 9 ft. 
.SUN...S wind 25 kt. Seas 14 ft. 
.MON...S wind 25 kt. Seas 11 ft. 

$$

PKZ043-081745-
Cape Edgecumbe to Cape Fairweather-
336 PM AKDT Wed Apr 7 2021

...GALE WARNING THURSDAY...

.TONIGHT...SW wind 15 kt. Seas 9 ft. Rain late. 
.THU...SE wind 40 kt becoming SW in the afternoon. Seas
17 ft. Rain.
.THU NIGHT...S gale to 35 kt becoming W late. Seas 20 ft.
Rain.
.FRI...W wind 25 kt. Seas 18 ft. W swell. 
.FRI NIGHT...W wind 25 kt. Seas 16 ft. W swell. 
.SAT...W wind 20 kt becoming S. Seas 12 ft subsiding to
7 ft. 
.SUN...S wind 25 kt. Seas 14 ft. 
.MON...S wind 25 kt. Seas 11 ft. 

$$

PKZ051-081745-
Cape Fairweather to Icy Cape-
336 PM AKDT Wed Apr 7 2021

...GALE WARNING THURSDAY...

.TONIGHT...E wind 15 kt becoming SE 25 kt late. Seas 8 ft. Rain
late. 
.THU...SE wind 45 kt. Seas 15 ft. Rain.
.THU NIGHT...E wind 25 kt. Seas 14 ft. Rain in the evening. 
.FRI...NE wind 25 kt. Seas 13 ft. 
.FRI NIGHT...NE wind 20 kt. Seas 12 ft. 
.SAT...SE wind 15 kt. Seas 8 ft. 
.SUN...S wind 25 kt. Seas 13 ft. 
.MON...S wind 25 kt. Seas 10 ft. 

$$

PKZ052-081745-
Icy Cape to Cape Suckling-
336 PM AKDT Wed Apr 7 2021

...STORM WARNING THURSDAY...

.TONIGHT...NW wind 15 kt becoming SE in the evening, then
increasing to 35 kt late. Seas 6 ft building to 12 ft late. Rain
with snow late. 
.THU...E wind 50 kt diminishing to 40 kt in the afternoon.
Seas 18 ft. Rain and snow in the morning, then rain in the
afternoon. 
.THU NIGHT...E wind 20 kt becoming N late. Seas 13 ft. 
.FRI...NW wind 30 kt. Seas 13 ft. 
.FRI NIGHT...NW wind 25 kt. Seas 11 ft. 
.SAT...W wind 15 kt becoming SE. Seas 7 ft. 
.SUN...SE wind 30 kt. Seas 11 ft. 
.MON...SE wind 20 kt. Seas 9 ft. 

$$

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
308 PM AKDT Tue Apr 6 2021

.SHORT TERM...Tuesdays forecast is a tale of two lows, the first is
on its way out this evening and the second is poised to impact the
area on Friday.

The first low over the northern gulf is the remains of the system
that moved into Western Canada Monday. This low will weaken and move
slowly southeast tonight and dissipate over the south central
panhandle early Wednesday. As the low moves southeast, showers will
be tapering off and ending from the north-northwest to
south-southwest.

Brief clearing skies are expected after the low while the surface
ridge axis and the small ridge aloft transitions eastward across the
gulf and panhandle Wednesday and Wednesday night. With the northern
gulf seeing clearing tonight fog could develop, though think it will
probably frost out. Wednesday the fog may redevelop for some of the
south central panhandle.

The models are in generally good agreement that a strong springtime
storm will move out of the southern portion of the Alaskan mainland
and deepen into the lower 980s mb. The various solutions are within
about 100 nm of each other. However the wind directions and speeds
through the panhandle fluctuate substantially depending on the exact
location of the features. Winds over the outer coastal waters will
blow 35 to 45 kt as the front moves through. The front will continue
through the panhandle Thursday afternoon and evening with 30 to
locally 40 kts winds for the inner channels. Communities along the
coasts may gust to around 40 mph as the system moves through.

The precipitation expected from this front looks like it will be
between 0.5 and 1.5 inches of water. Flooding concerns are low other
than nuisance from drainage issues. However the rain on the snow
pack aloft may make it more unstable and more susceptible to slide.
Also some the northern portion of the panhandle is likely to have
some cooler air still trapped in the valleys and channels. As a
result we continue monitoring the threat of accumulations of snow
with its passage. Early estimates show the potential for 2 to 4
inches in the north.

.LONG TERM.../Thursday through Monday/ As of 10pm Monday. The big
story continues to be the approaching Thursday and Friday system.
This system still looks like it has the potential to bring
accumulating snow to the northern panhandle and Icy Strait
Corridor, but pinning down exact details remains a challenge.
Notably enough, both operational and ensemble suites have
continued to differ from run to run on the track of the system. It
now looks increasingly likely that the low will slide off to the
South along the outer coast. This will set up the conditions for a
battle between the colder air wrapping in behind the low, and the
WAA moving up from the South. GFS and NAM runs both indicate that
this WAA should be sufficient to force a transition to rain or to
a rain snow mix across much of the area on Thursday. Given the
lateness of the season, am currently leaning towards this
solution, which would limit snow totals substantially. However,
the specter of snow melt cooling remains present, and the extent
of any possible switchover will depend on whether or not the Warm
Air Advection can make it down to the surface. For the time being,
have some minor snow accumulations across the Icy Strait Corridor
and Yakutat, with more substantial accumulations in the northern
panhandle. Minor shifts in the track of the low and the
temperatures across the area will mean the difference between
receiving a late season wintry blast or additional rainfall. The
system will also likely bring breezy conditions throughout the
area, and all of these elements will need to be closely monitored
as more data becomes available.

The system will likely remain around the area for some time before
sliding S and then moving across the central Panhandle. There is
a possibility of a brief period of clearing for Saturday should
the system depart through Friday night as the Euro depicts. On the
other hand, the GFS ensemble still shows a slower moving trough
aloft resulting in the low slowing down over the Gulf for a time.
Should this scenario play out, it is entirely possible that the
system may not depart until Sunday, ahead of another approaching
system which models have begun to depict.

Due to model inconsistencies, there is lower forecast confidence
overall, with snow accumulation totals and the exact track of the
Thursday low remaining the primary areas of concern.

&&

.MARINE...Winds for the most part under small craft levels
tonight with exception of a northerly gale force developing through
Lynn Canal tonight and early Wednesday. A small craft will run
south through Chatham Strait past Point Gardner for Wednesday
morning. The next incoming system will be even more impressive.
35 to 45 kt winds ahead of the front beginning early Thursday
morning. The front will sweep through the panhandle With 30 to 40
kt winds expected in the inner channels from Icy Strait southward,
only Lynn Canal and Glacier Bay should have sub 25 kt winds
during the day.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Gale Warning for PKZ012-013.
     Small Craft Advisory for PKZ031>033-041>043.

&&

Bezenek/GFS

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