Gale Warning 309, NWS Juneau, AK

362 
FZAK51 PAJK 171326
CWFAJK

Coastal Waters Forecast FOR Southeast Alaska
National Weather Service Juneau AK
426 AM AKST Sun Dec 17 2017

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

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.

PKZ098-180430-
426 AM AKST Sun Dec 17 2017
.SYNOPSIS FOR SOUTHEAST ALASKA INNER CHANNELS COASTAL WATERS...
A weakening surface low will continue to progress east into the 
east-central gulf today and remain nearly stationary until early 
Monday. The low will then be pushed southeast by a building 
surface high pressure near the Canadian border Monday into Monday 
night. 

$$

PKZ011-180430-
Glacier Bay-
426 AM AKST Sun Dec 17 2017

.TODAY...SE wind 15 kt. Seas 3 ft. Scattered rain and snow
showers. 
.TONIGHT...SE wind 10 kt becoming N late. Seas 2 ft or less.
Scattered rain and snow showers in the evening.
.MON...N wind 15 kt. Seas 3 ft. Scattered snow showers.
Isolated rain showers in the morning. 
.MON NIGHT...N wind 20 kt. Seas 4 ft. 
.TUE...N wind 25 kt. Seas 5 ft. 
.WED...SE wind 10 kt. Seas 2 ft or less. 
.THU...SW wind 10 kt becoming N 15 kt. Seas 3 ft. 

$$

PKZ012-180430-
Northern Lynn Canal-
426 AM AKST Sun Dec 17 2017

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

.TODAY...S wind 25 kt diminishing this afternoon. Seas 5 ft. 
Scattered rain and snow showers.
.TONIGHT...S wind 15 kt becoming N late. Seas 3 ft. Scattered
rain and snow showers in the evening. 
.MON...N wind 25 kt increasing to gale to 35 kt in the
afternoon. Seas 7 ft. Scattered snow showers. 
.MON NIGHT...N gale to 35 kt. Gusts to 50 kt. Seas 7 ft. 
.TUE...N wind 30 kt. Seas 6 ft. 
.WED...S wind 10 kt. Seas 2 ft or less. 
.THU...S wind 10 kt becoming N 15 kt. Seas 3 ft. 

$$

PKZ013-180430-
Southern Lynn Canal-
426 AM AKST Sun Dec 17 2017

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

.TODAY...S wind 30 kt diminishing to 20 kt in the afternoon. Seas
5 ft. Rain and snow showers. 
.TONIGHT...SE wind 15 kt becoming N late. Seas 3 ft. Scattered
rain and snow showers in the evening.  
.MON...N wind 20 kt increasing to 30 kt in the afternoon. Seas
5 ft. Scattered rain and snow showers in the morning.
.MON NIGHT...N gale to 35 kt. Seas 7 ft. 
.TUE...N wind 25 kt. Seas 5 ft. 
.WED...S wind 10 kt. Seas 2 ft or less. 
.THU...S wind 10 kt becoming N 15 kt. Seas 3 ft. 

$$

PKZ021-180430-
Icy Strait-
426 AM AKST Sun Dec 17 2017

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

.TODAY...SW wind 25 kt becoming E. Higher winds west of Point
Adolphus. Seas 5 ft. Rain and snow showers.
.TONIGHT...SE wind 10 kt. Seas 2 ft or less. Scattered rain
showers in the evening. Scattered snow showers. 
.MON...E wind 15 kt. Seas 3 ft. Scattered rain and snow showers.
.MON NIGHT...NE wind 20 kt. Seas 4 ft. 
.TUE...NW wind 20 kt. Seas 4 ft. 
.WED...SE wind 10 kt. Seas 2 ft or less. 
.THU...E wind 15 kt. Seas 3 ft. 

$$

PKZ022-180430-
Cross Sound-
426 AM AKST Sun Dec 17 2017

...SMALL CRAFT ADVISORY THROUGH LATE TONIGHT...

.TODAY...SW wind 25 kt diminishing to 15 kt in the afternoon.
Seas 12 ft. Isolated thunderstorms early in the morning. Rain
showers.  
.TONIGHT...W wind 15 kt becoming E late. Seas 11 ft. S swell.
Scattered rain and snow showers in the evening. 
.MON...NE wind 25 kt. Seas 11 ft. S swell. Scattered rain and 
snow showers in the morning. 
.MON NIGHT...E wind 20 kt. Seas 9 ft. S swell. 
.TUE...E wind 20 kt. Seas 7 ft. 
.WED...W wind 10 kt. Seas 7 ft. 
.THU...NW wind 15 kt. Seas 5 ft. 

$$

PKZ031-180430-
Stephens Passage-
426 AM AKST Sun Dec 17 2017

.TODAY...S wind 20 kt. Seas 4 ft. Rain and snow showers. 
.TONIGHT...SE wind 15 kt. Seas 3 ft. Snow showers and rain
showers in the evening, then scattered snow showers late. 
.MON...E wind 15 kt. Seas 3 ft. Scattered snow showers.
Scattered rain showers in the afternoon. 
.MON NIGHT...N wind 20 kt. Seas 4 ft. Patchy fog.
.TUE...N wind 20 kt. Seas 4 ft. 
.WED...SE wind 15 kt. Seas 3 ft. 
.THU...SE wind 15 kt becoming NE. Seas 3 ft. 

$$

PKZ032-180430-
Northern Chatham Strait-
426 AM AKST Sun Dec 17 2017

.TODAY...S wind 15 kt. Seas 3 ft. Scattered rain and snow showers
early in the morning, then rain and snow showers. 
.TONIGHT...S wind 10 kt. Seas 2 ft or less. Scattered snow
showers and rain showers in the evening, then snow showers late. 
.MON...SE wind 15 kt becoming N in the afternoon. Seas 3 ft.
Snow showers in the morning, then scattered rain and snow showers
in the afternoon. 
.MON NIGHT...N wind 20 kt. Seas 4 ft. Scattered snow showers. 
.TUE...N wind 20 kt. Seas 4 ft. 
.WED...SE wind 15 kt. Seas 3 ft. 
.THU...SE wind 15 kt. Seas 3 ft. 

$$

PKZ033-180430-
Southern Chatham Strait-
426 AM AKST Sun Dec 17 2017

.TODAY...S wind 15 kt. Seas 4 ft, except 11 ft near ocean
entrances. Scattered rain showers early in the morning, then rain
showers. 
.TONIGHT...S wind 15 kt. Seas 3 ft, except 11 ft near ocean
entrances. Rain and snow showers. 
.MON...S wind 15 kt becoming NE in the afternoon. Seas 3 ft,
except 9 ft near ocean entrances. Rain and snow showers in the 
morning. 
.MON NIGHT...N wind 15 kt. Seas 3 ft, except 7 ft near ocean
entrances. Scattered snow showers. 
.TUE...N wind 15 kt. Seas 3 ft. 
.WED...Light winds becoming S 15 kt. Seas 2 ft or less then 3 ft.
.THU...SE wind 15 kt. Seas 3 ft. 

$$

PKZ034-180430-
Frederick Sound-
426 AM AKST Sun Dec 17 2017

.TODAY...S wind 20 kt. Seas 4 ft. Scattered rain showers early in
the morning, then rain and snow showers.
.TONIGHT...SE wind 15 kt. Seas 3 ft. Rain and snow showers. 
.MON...E wind 15 kt. Seas 3 ft. Rain and snow showers in the 
morning, then scattered rain and snow showers in the afternoon. 
.MON NIGHT...NE wind 20 kt. Seas 4 ft. Patchy fog. Scattered
rain and snow showers. 
.TUE...NE wind 20 kt. Seas 4 ft. 
.WED...SE wind 15 kt. Seas 3 ft. 
.THU...SE wind 15 kt. Seas 3 ft. 

$$

PKZ035-180430-
Sumner Strait-
426 AM AKST Sun Dec 17 2017

.TODAY...S wind 15 kt. Seas 3 ft, except 6 ft near ocean
entrances. Scattered rain showers early in the morning, then rain
showers. Snow showers in the afternoon. 
.TONIGHT...S wind 15 kt. Seas 3 ft, except 6 ft near ocean
entrances. Scattered rain and snow showers in the evening. Rain 
showers late. 
.MON...S wind 20 kt becoming E in the afternoon. Seas 4 ft.
Rain and snow showers in the morning, then scattered rain and 
snow showers in the afternoon. 
.MON NIGHT...E wind 15 kt. Seas 3 ft. Scattered rain and snow
showers. 
.TUE...NE wind 20 kt. Seas 4 ft. 
.WED...E wind 15 kt. Seas 3 ft. 
.THU...SE wind 15 kt. Seas 3 ft. 

$$

PKZ036-180430-
Clarence Strait-
426 AM AKST Sun Dec 17 2017

.TODAY...SW wind 10 kt. Seas 3 ft, except 6 ft near ocean
entrances. Scattered rain showers early in the morning, then rain
and snow showers.
.TONIGHT...SE wind 15 kt. Seas 3 ft, except 5 ft near ocean 
entrances. Scattered rain and snow showers in the evening, then 
rain and snow showers late. 
.MON...SE wind 20 kt. Seas 4 ft. Rain and snow showers. 
.MON NIGHT...N wind 20 kt. Seas 4 ft. Scattered rain and snow
showers. 
.TUE...NW wind 20 kt. Seas 4 ft. 
.WED...NW wind 10 kt becoming SE. Seas 2 ft or less. 
.THU...SE wind 15 kt. Seas 3 ft. 

$$

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
241 PM AKST Sat Dec 16 2017

.SHORT TERM.../Saturday through Monday as of 1 PM Saturday/

The weather front affecting the Panhandle has pushed through the
northern Panhandle and has almost made its way through the
southern Panhandle. Behind the front widespread shower activity
is expected through the evening. An area of interest is the far
northern gulf and the eastern gulf over the next 24 hours where
steeper lapse rates (faster cooling with height) will create a
more unstable atmosphere and allow for a chance of thunderstorms
in those areas. Sunday night through Monday a surface low will
track southeast through the gulf acting to keep the Panhandle wet.
Shower activity will diminish Monday from north to south as the
low tracks southeast. Surface high pressure builds over the gulf
and Panhandle behind this system which will act to dry southeast
Alaska out as Monday progresses.

Winds are primarily a concern this evening as mainly over the
northern Panhandle and with tip jets near Cross sound and Cape
Decision. Strongest winds will be near Skagway and gales will be
present in northern Lynn canal and near Cross Sound.

The seasonably warm above freezing temperatures decrease through
the short term. However, with the coolest temperatures being
Monday not much snow is expected across Southeast Alaska since
this will be the drying day for the Panhandle.

Not many significant changes were made in the short term. Primary
guidance was a blend of the GFS and ECMWF with some input from the
NAMNest and ARW to handle the shower activity behind the front.
POP was increased to allow for more widespread shower activity
this evening. Confidence is above average in the short term.

.LONG TERM.../Monday through Friday/ As of 10pm Friday

Yet another anomalously strong upper ridge continues to be
advertised by both operational models and their ensembles to
rapidly build over the Gulf of Alaska next week. Cool upper trough
over the northern Gulf early on Monday will quickly be shunted off
to the southeast ahead of this building ridge. Lingering shower
activity on Monday will likely be in the form of snow even to sea
level for the northern and interior inner channels from Haines
and Juneau as far south as Petersburg. Only light precip amounts
are expected and this will primarily be a case of the cold air
chasing the moisture so any snow accumulations would be minor.

Still looks like a very brief offshore flow even late monday into
Tuesday. Northerly winds will develop over the northern inner
channels on monday as the weak low offshore slides to the south.
Light northerly flow through the low levels will promote at least
some clearing by Monday night and Tuesday although will need to
watch for fog in places that are sheltered from the wind as the
ground will be saturated.

Low level flow becomes more NW'ly on Tuesday night into Wednesday
which is not necessarily a clear sky direction at times. Could see
some low level moisture and stratocumulus try to make a return
along the outer coast, however Wednesday should be another dry
day.

Upper ridge begins to shift east by late week with a series of
storm systems and their associated deep plumes of moisture riding
up the west side. At this time it appears the ridge will hold
strong enough to keep the deep fetch of moisture mainly to our
west, with only weakening fronts approaching from the west by
Thursday/Friday. Unfortunately for snow lovers, we are hard
pressed to find any significant hope for snow in the future as
freezing levels rise to around 5 kft by late week under the strong
ridging aloft.

&&

.AVIATION.../As of 130 pm Saturday/ Most of the Panhandle is
behind the front besides the far southeast Panhandle. Shower
activity will be widespread behind this system through tonight.
This will keep conditions primarily MVFR; however, as stronger
showers pass through expect short periods of IFR conditions. In
addition to the lower ceilings and visibilities associated with
showers, westerly low level windshear will exists over much of the
panhandle through tomorrow morning. Shower activity will begin to
diminish late tomorrow.

&&

.AJK Watches/Warnings/Advisories...
PUBLIC...Winter Storm Warning until 3 PM AKST this afternoon for AKZ018.
     Strong Wind from 6 PM AKST this evening through late tonight for
     AKZ018.
MARINE...Gale Warning for PKZ012-022.
     Small Craft Advisory for PKZ013-021-031-032-034-036-041>043-051-
     052.
     Small Craft Advisory due to Seas for PKZ053.

&&

JB/DEL

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