Gale Warning 183, NWS Juneau, AK

935 
FZAK67 PAJK 161125
OFFAJK

Offshore Waters Forecast
National Weather Service Juneau AK
325 AM AKDT Sat Sep 16 2017

Offshore waters forecast for Gulf of Alaska east of 144W

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.

PKZ398-170530-
325 AM AKDT Sat Sep 16 2017
.SYNOPSIS FOR THE EASTERN GULF OF ALASKA...
A gale force low moving into the western Gulf of Alaska will
push a front across the eastern gulf Saturday. Gales will
develop Saturday over the gulf and near shore zones ahead of 
this front.  

$$

PKZ310-170530-
Gulf of Alaska North of 55 Degrees North and East of 144 Degrees
West-
325 AM AKDT Sat Sep 16 2017

...GALE WARNING TODAY...

.TODAY...S wind 25 kt increasing to 35 kt, then diminishing late 
in the afternoon. Seas 9 ft building to 12 ft in the afternoon. Rain.
.TONIGHT...SW wind 20 kt. Seas 12 ft. SW swell. 
.SUN...S wind 15 kt in the morning becoming variable less than
15 kt. Seas 15 ft. W swell. Slight chance of thunderstorms. 
.SUN NIGHT...NE wind 15 kt. Seas 15 ft. W swell. 
.MON...W wind 15 kt. Seas 10 ft. 
.TUE...W wind 15 kt. Seas 7 ft. 
.WED...W wind 15 kt. Seas 6 ft or less. 

$$

728 
FZAK67 PAJK 162322
OFFAJK

Offshore Waters Forecast
National Weather Service Juneau AK
322 PM AKDT Sat Sep 16 2017

Offshore waters forecast for Gulf of Alaska east of 144W

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.

PKZ398-171730-
322 PM AKDT Sat Sep 16 2017
.SYNOPSIS FOR THE EASTERN GULF OF ALASKA...
A gale force front over the eastern gulf will slowly weaken and
drift to the outer coast of SE AK by early Sun morning, then 
dissipate there by Sun evening. 

$$

PKZ310-171730-
Gulf of Alaska North of 55 Degrees North and East of 144 Degrees
West-
322 PM AKDT Sat Sep 16 2017

.TONIGHT...SW wind 25 kt. Seas 12 ft. SW swell. Rain early in the
evening. 
.SUN...S wind 15 kt in the morning becoming variable less than
15 kt. Seas 14 ft. W swell. Slight chance of thunderstorms. 
.SUN NIGHT...NE wind 15 kt. Seas 15 ft. W swell. 
.MON...W wind 15 kt. Seas 11 ft. W swell. 
.MON NIGHT...W wind 15 kt. Seas 8 ft. W swell. 
.TUE...W wind 15 kt. Seas 7 ft. 
.WED...W wind 15 kt. Seas 6 ft or less. 
.THU...W wind 15 kt. Seas 6 ft. 

$$

Southeast Alaska Forecast Discussion
National Weather Service Juneau AK
253 PM AKDT Fri Sep 15 2017

.SYNOPSIS...A ridge of high pressure over the eastern gulf will
continue to weaken Friday night, as a weather front moves into
the central gulf. This front will move eastward this through the
weekend.

&&

.SHORT TERM.../Friday Night through Sunday/ A weather front
located over the central gulf will move eastward through the night
Friday. Chances of rain associated with the front continue to
build through the overnight hours. Rain is forecasted to begin
along the outer coast Saturday and spread inland through the day
Saturday. The extent that the front's precipitation is able to
penetrate into the panhandle remains an area of uncertainty in the
forecast as easterly upper level winds act to counteract the
fronts approach from the west. Most of the significant winds are
confined to the gulf where gales are forecasted; however, gustier
winds near Cross Sound and Cape Decision are likely as the front
approaches. Largest rainfall totals are expected to remain along
the outer coast. Sunday is expected to follow a diminishing shower
and decreasing wind trend.

Significant changes were not made in the short term. Winds were
increased slightly within the inner channels Saturday and Sunday
associated with the front. In addition QPF values were raised
slightly after coordinating with the RFC. Primary guidance was a
blend of the NAM and GFS with RFC's QPF fields used.

.LONG TERM.../Sunday through Friday/Extended forecast starts out
with what is left of the weekend front diminishing along the
southern outer coast on Sun with most of the rain moving out Sun
night. Mon still looks mostly dry but some models are suggesting
that some easterly waves may bring some light precip especially to
the southern half of the panhandle. Decided to keep some chance
pops for that area as a result with mostly cloudy to cloudy skies
as a result.

Past this point the forecast becomes more uncertain as some short
wave energy comes across the gulf for Tue. Most models don't do
much with it getting a 1008 mb low at most. The GFS on the other
hand decides that it is going to turn it into a 990 mb gale force
low that heads towards Haida Gwaii. Since there is no other
support for this (even from the ensemble means) decided to regard
the GFS suggestion as an outlier and mainly focus on the ECMWF and
Ensembles for guidance. The result is some chance to likely pops
for Tue with more chances of rain after that as agreement between
the models becomes poor with the next series of front approaching
for late week.

The wind forecast has average confidence with no significant
winds (25 kt or higher) expected through at least mid next week.
General direction is some variation of westerly as various weak
troughs and ridges move through.

&&

.AJK Watches/Warnings/Advisories...
PUBLIC...None.
MARINE...Gale Warning for PKZ043-051-052.
     Small Craft Advisory for PKZ022-041-042.
     Small Craft Advisory due to Seas for PKZ053.

&&

Byrd/EAL

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