Gale Warning 9, NWS Juneau, AK

317 
FZAK52 PAJK 030012
CWFAEG

COASTAL WATERS FORECAST FOR SOUTHEAST ALASKA
National Weather Service Juneau AK
312 PM AKST Tue Jan 2 2018

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.

PKZ099-031815-
312 PM AKST Tue Jan 2 2018
.SYNOPSIS FOR OUTSIDE WATERS...
A weather front will remain over the eastern gulf through
tonight as a low pressure wave moves N along it. The front will 
then move into SE AK Wed morning, then stall over central SE AK by
Wed afternoon. 

$$

PKZ041-031815-
Dixon Entrance to Cape Decision-
312 PM AKST Tue Jan 2 2018

...GALE WARNING THROUGH THIS EVENING...

.TONIGHT...SE wind 35 kt diminishing to 30 in the evening. Seas 
18 ft. Rain.
.WED...SE wind 20 kt. Seas 14 ft. W swell. Rain.
.WED NIGHT...SE wind 25 kt. Seas 11 ft. W swell. Rain.
.THU...SE wind 30 kt. Seas 11 ft. Rain.
.THU NIGHT...SE wind 25 kt. Seas 10 ft. 
.FRI...NW wind 20 kt. Seas 9 ft. 
.SAT...S wind 10 kt. Seas 9 ft. 
.SUN...SE wind 15 kt. Seas 10 ft. 

$$

PKZ042-031815-
Cape Decision to Cape Edgecumbe-
312 PM AKST Tue Jan 2 2018

...GALE WARNING THROUGH LATE TONIGHT...

.TONIGHT...S wind 35 kt diminishing to 25 overnight. Seas 19 ft. 
Rain.
.WED...SE wind 15 kt. Seas 14 ft. SW swell. Rain.
.WED NIGHT...E wind 25 kt. Seas 11 ft. SW swell. Rain.
.THU...E wind 20 kt. Seas 10 ft. Rain.
.THU NIGHT...E wind 20 kt. Seas 10 ft. 
.FRI...NW wind 20 kt. Seas 9 ft. 
.SAT...SE wind 15 kt. Seas 11 ft. 
.SUN...E wind 10 kt. Seas 11 ft. 

$$

PKZ043-031815-
Cape Edgecumbe to Cape Fairweather-
312 PM AKST Tue Jan 2 2018

...GALE WARNING THROUGH LATE TONIGHT...

.TONIGHT...S wind 40 kt diminishing to 25 kt late. Seas 20 ft. 
Rain in the evening.
.WED...SW wind 15 kt. Seas 14 ft. SW swell. 
.WED NIGHT...N wind 15 kt. Seas 10 ft. SW swell. 
.THU...N wind 25 kt. Seas 9 ft. 
.THU NIGHT...N wind 20 kt. Seas 9 ft. 
.FRI...NW wind 15 kt becoming SE. Seas 9 ft. 
.SAT...SE wind 20 kt. Seas 13 ft. 
.SUN...SE wind 15 kt. Seas 11 ft. 

$$

PKZ051-031815-
Cape Fairweather to Icy Cape-
312 PM AKST Tue Jan 2 2018

...GALE WARNING THROUGH LATE TONIGHT...

.TONIGHT...S wind 35 kt. Gusts to 45 kt out of interior bays and 
passes. Seas 20 ft. Rain in the evening. 
.WED...S wind 15 kt shifting to W wind 10 kt. Seas 14 ft. SW 
swell.
.WED NIGHT...N wind 15 kt. Seas 10 ft. SW swell. 
.THU...NW wind 25 kt. Seas 8 ft. SW swell. 
.THU NIGHT...N wind 20 kt. Seas 8 ft. 
.FRI...N wind 15 kt becoming SE. Seas 9 ft. 
.SAT...SE wind 25 kt. Seas 12 ft. 
.SUN...SE wind 10 kt. Seas 11 ft. 

$$

PKZ052-031815-
Icy Cape to Cape Suckling-
312 PM AKST Tue Jan 2 2018

...SMALL CRAFT ADVISORY THROUGH WEDNESDAY...

.TONIGHT...SE wind 30 kt. Seas 20 ft. Rain in the evening. 
.WED...SW wind 15 kt. Seas 13 ft. SW swell. 
.WED NIGHT...NW wind 15 kt. Seas 9 ft. SW swell. 
.THU...NW wind 20 kt. Seas 8 ft. SW swell. 
.THU NIGHT...N wind 20 kt. Seas 7 ft. SW swell. 
.FRI...N wind 10 kt becoming SE 25 kt. Seas 5 ft building to
11 ft. 
.SAT...SE wind 25 kt. Seas 13 ft. 
.SUN...E wind 15 kt. Seas 11 ft. 

$$

324 
FZAK52 PAJK 031321
CWFAEG

COASTAL WATERS FORECAST FOR SOUTHEAST ALASKA
National Weather Service Juneau AK
421 AM AKST Wed Jan 3 2018

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.

PKZ099-040730-
421 AM AKST Wed Jan 3 2018
.SYNOPSIS FOR OUTSIDE WATERS...
A weather front will move E into the northern panhandle Wed
morning, then stall over the N central panhandle by Wed
afternoon. A low pressure area will move NE to the far SE gulf by
Thu morning. 

$$

PKZ041-040730-
Dixon Entrance to Cape Decision-
421 AM AKST Wed Jan 3 2018

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

.TODAY...SE wind 30 kt diminishing to 20 kt in the afternoon. 
Seas 15 ft subsiding to 11 ft in the afternoon. Rain.
.TONIGHT...SE wind 25 kt. Seas 10 ft. W swell. Rain.
.THU...SE wind 25 kt. Seas 10 ft. Rain.
.THU NIGHT...SE wind 25 kt. Seas 9 ft. Rain.
.FRI...S wind 20 kt. Seas 9 ft. 
.SAT...SE wind 20 kt becoming W. Seas 10 ft. 
.SUN...E wind 10 kt. Seas 10 ft. 

$$

PKZ042-040730-
Cape Decision to Cape Edgecumbe-
421 AM AKST Wed Jan 3 2018

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

.TODAY...S wind 30 kt becoming SE 15 kt in the afternoon. Seas 15
ft subsiding to 11 ft in the afternoon. Rain.
.TONIGHT...E wind 25 kt. Seas 10 ft. SW swell. Rain.
.THU...E wind 20 kt. Seas 8 ft. W swell. Rain.
.THU NIGHT...E wind 20 kt. Seas 9 ft. W swell. Rain.
.FRI...SE wind 15 kt. Seas 9 ft. 
.SAT...SE wind 20 kt. Seas 10 ft. 
.SUN...E wind 10 kt. Seas 11 ft. 

$$

PKZ043-040730-
Cape Edgecumbe to Cape Fairweather-
421 AM AKST Wed Jan 3 2018

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

.TODAY...S wind 30 kt becoming SW 15 kt in the afternoon. Seas 14
ft. Rain in the morning. 
.TONIGHT...N wind 15 kt. Seas 9 ft. SW swell. Rain.
.THU...N wind 25 kt. Seas 8 ft. SW swell. Rain.
.THU NIGHT...N wind 20 kt. Seas 9 ft. Rain.
.FRI...NE wind 20 kt becoming SE. Seas 9 ft. 
.SAT...SE wind 20 kt. Seas 10 ft. 
.SUN...E wind 10 kt. Seas 11 ft. 

$$

PKZ051-040730-
Cape Fairweather to Icy Cape-
421 AM AKST Wed Jan 3 2018

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

.TODAY...S wind 30 kt becoming W 15 kt in the afternoon. Seas 15 
ft subsiding to 11 ft in the afternoon. Rain early in the morning.
.TONIGHT...N wind 10 kt. Seas 9 ft. SW swell. 
.THU...NW wind 25 kt. Seas 8 ft. SW swell. 
.THU NIGHT...N wind 20 kt. Seas 7 ft. SW swell. 
.FRI...E wind 15 kt. Seas 8 ft. 
.SAT...SE wind 20 kt. Seas 10 ft. 
.SUN...E wind 10 kt. Seas 10 ft. 

$$

PKZ052-040730-
Icy Cape to Cape Suckling-
421 AM AKST Wed Jan 3 2018

...SMALL CRAFT ADVISORY DUE TO SEAS THROUGH LATE TONIGHT...

.TODAY...SW wind 15 kt. Seas 12 ft. SW swell. Rain early in the
morning. 
.TONIGHT...NW wind 15 kt. Seas 9 ft. SW swell. 
.THU...NW wind 20 kt. Seas 7 ft. SW swell. 
.THU NIGHT...NW wind 20 kt. Seas 6 ft. SW swell. 
.FRI...N wind 10 kt becoming E 20 kt. Seas 6 ft. 
.SAT...SE wind 20 kt. Seas 10 ft. 
.SUN...E wind 10 kt. Seas 10 ft. 

$$

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
301 PM AKST Mon Jan 1 2018

.SHORT TERM...Our weather front that initially brought snow to
the panhandle late last night has made its way through, and now,
an additional weather front can be seen on satellite imagery
moving through the eastern gulf. Most locations reported a few
inches of snow this morning, and some locations even reported
freezing rain later on in the day, with Wrangell reporting
accumulating ice. This was caused by substantial below freezing
air in place near the surface with much warmer air aloft. This
allowed snow to melt while falling through the warm layer of air
and then allowed it to refreeze after coming into contact with the
colder surfaces. Many sites continue to report precipitation but
of the liquid variety as our next front begins to impact the
panhandle, save for our more northern areas, such as Haines and
Skagway, that continue to report snow. We have kept the Winter
Storm Warnings for both the Haines and Klondike Highways to
account for this longer period of snow, as the warmer air has
taken longer to reach here. Eventually, all locations will make a
full transition to rain, as strong warm air advection takes place
ahead of the next front.

This will be a relatively active pattern for the next coming
days, with warmer temperatures and higher precipitation amounts
expected than our previous pattern. At the upper levels of the
atmosphere, a broad, deep trough has developed over the western
gulf and will remain relatively steady here, while a ridge, in
some form or another, remains over the eastern gulf. This broad
trough will contain additional shortwave troughs that will be
advected from the parent circulation and will propagate east,
impacting the panhandle. With our next front moving through
tonight, we expect winds to reach majority Small Craft Advisory
levels throughout the inner channels, with Gales possible through
N Lynn Canal. We also have a Strong Wind headline for the Skagway
and White Pass areas, since we're expecting gusts of 40 mph there
with the front passing through tonight. Marine zones along the
gulf waters will remain near SCA levels through Wednesday due to
the tighter pressure gradient between these two major systems. As
subsequent weather fronts progress east through the panhandle,
winds along the inner channels will float with SCA levels, as each
short burst with the front will increase winds along the inside
waters, albeit briefly. Anomalously high precipitable water
amounts coupled with onshore flow will keep precipitation going
for most areas in the panhandle for the next few days.

We opted not to make many significant changes in the short term,
as model agreement has been lacking, especially past Wednesday.
Any changes we made to the forecast, we used a combination of the
GFS and GEM for any updates.

.LONG TERM.../Wednesday through Sunday night/ Somewhat active and
uncertain long range forecast today. Overall upper level pattern
retains the same idea of a ridge over the western US and trough
over the Bering Sea resulting in general SW flow over the forecast
area. This pattern is only interrupted in the late week period by
a short wave trough moving W to E across the area. Noticeable
differences between operational models on this trough with the GFS
much more progressive moving the trough E then the ECMWF. However
The GFS has better run to run consistency on this feature today,
plus the ensemble means and WPC were supporting this scenario as
well so leaned more in that direction for extended updates.

At the surface, the most noticeable change was for the Wed into
Thu period as current model trends showed the front that was in
the gulf at that time much closer to the panhandle. The result is
a reduction in wind speeds across the gulf (except for near the
panhandle) at that time. Otherwise, that front is still bringing
precip to the area with most areas still warm enough for it to
mostly be rain.

Past Thu, the forecast of where that front goes becomes rather
uncertain due to the differences showing up handling the upper
trough moving through that was mentioned above. The GFS favors a
much more progressive pattern with the front clearing the
panhandle by Fri morning. Some colder air is also being dragged
into the panhandle by the upper trough for Fri into Sat. The ECMWF
on the other hand develops a weak low in the SE gulf that
eventually drifts into the central gulf significantly delaying the
eastward movement of the front and keeping the panhandle much
warmer then the gfs scenario. The differences just keep piling on
from there so favored a more ensemble approach to the forecast
given the differences. Forecast confidence is below average for
Thursday and beyond.

&&

.AJK Watches/Warnings/Advisories...
PUBLIC...Winter Storm Warning until 6 PM AKST this evening for AKZ019.
     Winter Storm Warning until 6 AM AKST Tuesday for AKZ018.
     Strong Wind from 9 PM AKST this evening through late tonight for
     AKZ018.
     Winter Weather Advisory until midnight AKST tonight for AKZ029.
MARINE...Gale Warning for PKZ012-022-043-051-052.
     Small Craft Advisory for PKZ011-013-021-031>036-041-042-053.

&&

Voveris/EAL

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