Small Craft Advisory 128, NWS Juneau, AK

128 
FZAK51 PAJK 281243
CWFAJK

Coastal Waters Forecast for Southeast Alaska
National Weather Service Juneau AK
343 AM AKST Sun Feb 28 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.

PKZ098-010330-
343 AM AKST Sun Feb 28 2021
.SYNOPSIS FOR SOUTHEAST ALASKA INNER CHANNELS COASTAL WATERS...
A low moves through the NE Gulf Coast Sunday. A second low moves
into the northern gulf on Monday. Strong SW  onshore flow
continues through Monday.  

$$

PKZ011-010330-
Glacier Bay-
343 AM AKST Sun Feb 28 2021

.TODAY...SE wind 20 kt. Seas 4 ft. Rain showers and snow showers.
.TONIGHT...S wind 20 kt becoming NW 10 kt late. Gusts to 35 kt in
the evening. Seas 4 ft in the evening then 2 ft or less. Rain
showers and snow showers. 
.MON...S wind 20 kt. Seas 4 ft. Rain and snow. 
.MON NIGHT...SE wind 20 kt. Gusts to 35 kt. Seas 4 ft. Rain
showers and snow showers. 
.TUE...SE wind 15 kt. Seas 3 ft. 
.WED...N wind 10 kt. Seas 2 ft or less. 
.THU...N wind 10 kt. Seas 2 ft or less. 

$$

PKZ012-010330-
Northern Lynn Canal-
343 AM AKST Sun Feb 28 2021

...GALE WARNING THIS AFTERNOON...

.TODAY...S wind increasing to 35 kt. Seas 7 ft. Rain showers. 
.TONIGHT...S wind 30 kt diminishing to 20 kt late. Seas 5 ft.
Rain showers in the evening, then snow showers and rain showers
late. 
.MON...S wind 20 kt increasing to 30 kt in the afternoon. Seas
5 ft. Rain and snow. 
.MON NIGHT...S gale to 35 kt. Seas 7 ft. Rain showers and snow
showers. 
.TUE...S wind 15 kt. Seas 3 ft. 
.WED...NW wind 10 kt. Seas 2 ft or less. 
.THU...N wind 15 kt. Seas 3 ft. 

$$

PKZ013-010330-
Southern Lynn Canal-
343 AM AKST Sun Feb 28 2021

...GALE WARNING THIS AFTERNOON...

.TODAY...S wind 15 kt increasing to 35 kt in the afternoon. Seas
building to 7 ft. Rain showers. 
.TONIGHT...SE wind 20 kt. Seas 4 ft. Rain showers. Snow showers 
late. 
.MON...S wind 15 kt increasing to 25 kt in the afternoon. Seas
building to 5 ft. Snow in the morning. Rain.
.MON NIGHT...SE wind 25 kt. Gusts to 40 kt. Seas 5 ft. Rain
showers. 
.TUE...S wind 20 kt. Seas 4 ft. 
.WED...NW wind 10 kt. Seas 2 ft or less. 
.THU...N wind 15 kt. Seas 3 ft. 

$$

PKZ021-010330-
Icy Strait-
343 AM AKST Sun Feb 28 2021

...GALE WARNING THROUGH THIS AFTERNOON...

.TODAY...SE wind 20 kt increasing to 35 kt. Seas building to 7 
ft. Rain showers.
.TONIGHT...SE wind 15 kt. Seas 3 ft. Rain showers in the evening,
then rain showers and snow showers late. 
.MON...S wind 15 kt. Seas 3 ft. Snow in the morning. Rain.
.MON NIGHT...SE wind 25 kt. Seas 5 ft. Rain showers. 
.TUE...E wind 20 kt. Seas 4 ft. 
.WED...E wind 10 kt. Seas 2 ft or less. 
.THU...E wind 10 kt. Seas 2 ft or less. 

$$

PKZ022-010330-
Cross Sound-
343 AM AKST Sun Feb 28 2021

...GALE WARNING THIS AFTERNOON...

.TODAY...SW wind 20 kt becoming S 30 kt. Seas 9 ft building to 15
ft. Rain showers. Slight chance of thunderstorms. 
.TONIGHT...SW wind 20 kt. Seas 16 ft. S swell. Rain showers. 
.MON...SW wind 20 kt. Seas 13 ft. S swell. Rain.
.MON NIGHT...SW wind 25 kt. Seas 13 ft. S swell. Rain showers
and slight chance of thunderstorms. 
.TUE...SW wind 20 kt becoming E 10 kt. Seas 9 ft. 
.WED...E wind 15 kt. Seas 7 ft. 
.THU...E wind 15 kt. Seas 6 ft. 

$$

PKZ031-010330-
Stephens Passage-
343 AM AKST Sun Feb 28 2021

...GALE WARNING THROUGH THIS AFTERNOON...

.TODAY...S wind 30 kt. Seas 6 ft. Rain showers. 
.TONIGHT...S wind 25 kt. Seas 5 ft. Snow showers late. 
.MON...S wind 25 kt. Seas 5 ft. Snow in the morning, then rain
in the afternoon. 
.MON NIGHT...S wind 30 kt. Gusts to 45 kt. Seas 6 ft. Rain
showers. 
.TUE...S wind 20 kt. Seas 4 ft. 
.WED...S wind 15 kt becoming NE. Seas 3 ft. 
.THU...N wind 10 kt. Seas 2 ft or less. 

$$

PKZ032-010330-
Northern Chatham Strait-
343 AM AKST Sun Feb 28 2021

...GALE WARNING THIS AFTERNOON...

.TODAY...S wind 20 kt increasing to 35 kt. Seas building to 7 ft.
Rain showers.
.TONIGHT...S wind 25 kt. Seas 5 ft. 
.MON...S wind 20 kt. Seas 4 ft. Rain and snow in the morning,
then rain in the afternoon. 
.MON NIGHT...S wind 25 kt. Gusts to 40 kt. Seas 5 ft. Rain
showers. 
.TUE...S wind 15 kt. Seas 3 ft. 
.WED...S wind 10 kt becoming N. Seas 2 ft or less. 
.THU...N wind 15 kt. Seas 3 ft. 

$$

PKZ033-010330-
Southern Chatham Strait-
343 AM AKST Sun Feb 28 2021

...SMALL CRAFT ADVISORY THROUGH THIS AFTERNOON...

.TODAY...S wind 25 kt. Seas 5 ft, except 14 ft near ocean
entrances. Rain showers. 
.TONIGHT...S wind 20 kt. Seas 4 ft, except 14 ft near ocean
entrances. 
.MON...S wind 20 kt. Seas 4 ft, except 13 ft near ocean
entrances. Rain.
.MON NIGHT...SW wind 25 kt. Gusts to 40 kt. Seas 5 ft, except
13 ft near ocean entrances. Rain showers. 
.TUE...S wind 20 kt. Seas 4 ft. 
.WED...S wind 15 kt. Seas 3 ft. 
.THU...N wind 10 kt. Seas 2 ft or less. 

$$

PKZ034-010330-
Frederick Sound-
343 AM AKST Sun Feb 28 2021

...SMALL CRAFT ADVISORY THROUGH THIS AFTERNOON...

.TODAY...S wind 25 kt. Out of interior passes, gusts to 35 kt
early in the morning. Seas 5 ft. Rain showers early in the 
morning. 
.TONIGHT...S wind 20 kt. Seas 4 ft. 
.MON...S wind 20 kt. Seas 4 ft. Rain in the afternoon. 
.MON NIGHT...SE wind 20 kt. Gusts to 35 kt. Seas 4 ft. Rain
showers. 
.TUE...S wind 15 kt. Seas 3 ft. 
.WED...E wind 15 kt. Seas 3 ft. 
.THU...E wind 10 kt. Seas 2 ft or less. 

$$

PKZ035-010330-
Sumner Strait-
343 AM AKST Sun Feb 28 2021

...SMALL CRAFT ADVISORY THROUGH THIS MORNING...

.TODAY...SW wind 20 kt. Seas 4 ft, except 8 ft near ocean 
entrances. Rain showers. 
.TONIGHT...S wind 20 kt. Seas 4 ft, except 8 ft near ocean
entrances. 
.MON...S wind 15 kt increasing to 25 kt in the afternoon. Seas
building to 5 ft, except 7 ft near ocean entrances. Rain in the 
afternoon. 
.MON NIGHT...SW wind 25 kt. Seas 5 ft, except 8 ft near ocean
entrances. Rain showers. 
.TUE...S wind 15 kt. Seas 3 ft. 
.WED...E wind 10 kt. Seas 2 ft or less. 
.THU...E wind 10 kt. Seas 2 ft or less. 

$$

PKZ036-010330-
Clarence Strait-
343 AM AKST Sun Feb 28 2021

...SMALL CRAFT ADVISORY THROUGH THIS MORNING...

.TODAY...S wind 25 kt becoming SW 15 kt in the afternoon. Seas
subsiding to 3 ft, except 8 ft near ocean entrances. Rain 
showers.
.TONIGHT...S wind 15 kt. Seas 3 ft, except 6 ft near ocean
entrances. 
.MON...S wind 20 kt. Seas 4 ft, except 6 ft near ocean entrances.
.MON NIGHT...S wind 25 kt. Seas 5 ft, except 9 ft near ocean
entrances. Rain showers. 
.TUE...S wind 20 kt. Seas 4 ft. 
.WED...S wind 15 kt. Seas 3 ft. 
.THU...SE wind 15 kt. Seas 3 ft. 

$$

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
251 PM AKST Sat Feb 27 2021

SHORT TERM.../Through Monday night/...A surface low will develop
early tomorrow morning off the coast of Yakutat and move
northeast. This low will dissipate by Sunday evening. A second
low will develop in a similar location on Monday and again move
northeast over the Panhandle. Both systems will bring strong
onshore flow with offshore winds reaching up to 45 kts. Model
agreement for the position and timing of the surface lows are good
and was adjusted towards the NAM.

When the low associated with the present weather front finally
arrives near the northeast Gulf coast tomorrow, a strong
southerly pressure gradient will set up and produce high end small
craft winds over several of the inner channels. Strong winds are
also expected in Skagway and along the Klondike Highway.

A weak atmospheric river brought widespread precipitation into
the panhandle last night and will continue through tonight. A
Winter Storm Warning for the highways will remain in effect from
9pm this evening until 4pm Sunday with up to 11 inches of
snowfall. Through tonight, an additional 2 inches of snow is
expected in the back of the Juneau Valley and up to 4 inches of
snow in the town of Haines. Moderate chances of precipitation will
continue into Monday, before the second low pressure system
brings more uniform precipitation into the region. Highest amounts
at higher elevations, including the highways. Most areas near
sea- level will start as snow on Monday morning before changing to
rain or rain/snow mix due to warming temperatures. Precipitation
changing back to snow is likely at night due to temperatures
dropping below freezing across the panhandle. Highest snowfall
totals on the highways and Yakutat.

Due to consistent cloud cover, no large diurnal fluctuations
expected in the temperatures. Highs for tomorrow will be around 40
with lows near 30 except at higher elevations. Expect a similar
story for the next few days. Overall confidence is average.

LONG TERM.../Monday through Saturday night/...The active weather
pattern continues unabated as more systems move into Southeast
Alaska through late next week.

The period begins with the area experiencing lingering showers
from the most recent system to impact the panhandle. These showers
will soon be superceded by the next system racing towards the
panhandle on Monday. Uncertainties remain in the exact impacts
this system will generate. On one hand. The possibility of much of
the central and northern panhandle receiving accumulating snow
does exist. The 1290 thickness line, though rather marginal, does
enshroud much of the panhandle. In addition, 850 mb temps look to
remain on the cooler side, and snow melt cooling could definitely
work towards keeping precipitation snow in parts of the area
through Monday night. There are also indications that some
instability will be present, favoring heavy snow at least at the
start of the event, and snow levels will be fairly low. On the
other hand, the center of the low is currently favored to track
north of the bulk of the panhandle. This, along with broad SW
synoptic flow and its accompanying southerly warm air push, would
strongly lean more towards a rain- focused setup for much of the
area. While uncertainty remains high, chose to lean towards a
winter- setup for the time being, though toned down possible snow
totals substantial. Do expect that precipitation will at least
start as snow for parts of the panhandle. This being said, as
additional data becomes available, significant changes to the
forecast may prove necessary with regards to precipitation type.

As this system weakens, a broad low entering the Gulf from the
West will rotate impulses into the area, ensuring that chances of
precipitation remain in the forecast through much of the week. It
does look like there is the possibility of some drying for parts
of the panhandle late in the week. However, both operational and
ensemble guidance at this point remain in poor agreement this far
out, so confidence remains low. Overall forecast confidence in
precipitation chances remain good, but confidence in precipitation
type is low.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Storm Warning from 9 PM this evening to 4 PM AKST Sunday
     for AKZ018-019.
MARINE...Small Craft Advisory for PKZ012-013-022-031>036-041>043-051>053.

&&

KRT/Fritsch/GFS

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