Gale Warning 479, NWS Anchorage, AK

076 
FZAK62 PAFC 170111 AAA
OFFALU

Offshore Waters Forecast...UPDATED
National Weather Service Anchorage AK
511 PM AKDT Mon Oct 16 2017

Offshore Waters Forecast for the Bering Sea

wind forecasts reflect the predominant speed and direction
expected. Sea forecasts represent an average of the highest
one-third of the combined wind wave and swell height.

PKZ499-171415-
511 PM AKDT Mon Oct 16 2017
.SYNOPSIS FOR CENTRAL BERING SEA...

A 978 mb low at 54N 180E will move to 55N 163W at 972 mb Tue
morning...then it will move to 55N 150W at 970 mb by Tue evening.
A front will advance toward the western Aleutians Wed afternoon. 

$$

PKZ411-171415-
Bering Sea Offshore West of 180 and East of the International
Dateline-
511 PM AKDT Mon Oct 16 2017

...GALE WARNING TONIGHT...

.TONIGHT...NW wind 20 to 35 kt. Seas 7 to 12 ft. 
.TUE...W wind 10 to 20 kt. Seas 6 to 9 ft. 
.TUE NIGHT...W wind 10 to 20 kt. Seas 6 ft. 
.WED...NW wind up to 20 kt. Seas 6 ft. 
.WED NIGHT...E wind 15 to 30 kt. Seas 5 to 8 ft. 
.THU...NE wind 20 to 35 kt. Seas 8 to 13 ft. 
.FRI THROUGH SAT...NW wind 30 kt. Seas 9 to 15 ft.

$$

PKZ412-171415-
Bering Sea Offshore 171W to 180 and North of 56N-
511 PM AKDT Mon Oct 16 2017

.TONIGHT...NE wind 10 to 25 kt. Seas 5 to 10 ft. 
.TUE...NW wind 10 to 20 kt. Seas 6 to 10 ft. 
.TUE NIGHT...NW wind 10 to 20 kt. Seas 7 ft. 
.WED...NW wind 10 to 25 kt. Seas 7 ft. 
.WED NIGHT...NW wind up to 15 kt. Seas 6 ft. 
.THU...NE wind up to 20 kt. Seas 5 to 10 ft. 
.FRI THROUGH SAT...NW wind 30 kt. Seas 9 to 14 ft.

$$

PKZ413-171415-
Bering Sea Offshore 171W to 180 and South of 56N-
511 PM AKDT Mon Oct 16 2017

...GALE WARNING TONIGHT...

.TONIGHT...SE to NE wind 25 to 40 kt. Seas 9 to 13 ft. 
.TUE...NW wind 15 to 30 kt. Seas 8 to 13 ft. 
.TUE NIGHT...W wind 25 kt. Seas 7 to 10 ft. 
.WED...W wind 10 to 25 kt. Seas 6 to 9 ft. 
.WED NIGHT...W wind up to 20 kt. Seas 5 to 8 ft. 
.THU...E wind 15 to 30 kt. Seas 8 to 13 ft. 
.FRI THROUGH SAT...NW wind 20 to 30 kt. Seas 9 to 15 ft.

$$

PKZ414-171415-
Bering Sea Offshore East of 171W-
511 PM AKDT Mon Oct 16 2017

...GALE WARNING TONIGHT...

.TONIGHT...E wind 20 to 35 kt. Seas 6 to 11 ft. Rain showers. 
.TUE...N wind 15 to 30 kt. Seas 6 to 11 ft. 
.TUE NIGHT...NW wind 10 to 25 kt. Seas 6 to 10 ft. 
.WED...NW wind 15 to 25 kt. Seas 5 to 9 ft. 
.WED NIGHT...NW wind 10 to 25 kt. Seas 7 to 10 ft. 
.THU THROUGH SAT...NW wind 10 to 25 kt. Seas 6 to 11 ft.

$$

636 
FZAK62 PAFC 171126
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
326 AM AKDT Tue Oct 17 2017

Offshore Waters Forecast for the Bering Sea

Wind forecasts reflect the predominant speed and direction
expected. Sea forecasts represent an average of the highest
one-third of the combined wind wave and swell height.

PKZ499-180045-
326 AM AKDT Tue Oct 17 2017
.SYNOPSIS FOR CENTRAL BERING SEA...
A 976 mb low at 54N 165W moves to 54N 149W at 968 mb Wed morning.
A 974 mb Kamchatka low will move to 51N 169E at 988 mb Thu morning.

$$

PKZ411-180045-
Bering Sea Offshore West of 180 and East of the International
Dateline-
326 AM AKDT Tue Oct 17 2017

.TODAY...W wind 10 to 20 kt. Seas 6 to 9 ft.
.TONIGHT...W wind 10 to 20 kt. Seas 7 ft.
.WED...NW wind 10 to 20 kt. Seas 7 ft.
.WED NIGHT...E wind 15 to 30 kt. Seas 4 to 8 ft.
.THU...NE wind 15 to 30 kt. Seas 7 to 12 ft.
.FRI THROUGH SAT...NW wind 30 kt. Seas 8 to 12 ft.

$$

PKZ412-180045-
Bering Sea Offshore 171W to 180 and North of 56N-
326 AM AKDT Tue Oct 17 2017

.TODAY...NW wind 10 to 20 kt. Seas 6 to 9 ft.
.TONIGHT...W wind 10 to 20 kt. Seas 7 ft.
.WED...NW wind 10 to 25 kt. Seas 7 ft.
.WED NIGHT...NW wind up to 20 kt. Seas 6 ft.
.THU THROUGH FRI...N wind 10 to 25 kt. Seas 5 to 10 ft.
.SAT...NW wind 30 kt. Seas 9 to 12 ft.

$$

PKZ413-180045-
Bering Sea Offshore 171W to 180 and South of 56N-
326 AM AKDT Tue Oct 17 2017

.TODAY...NW wind 15 to 30 kt. Seas 8 to 11 ft.
.TONIGHT...W wind 25 kt. Seas 8 ft.
.WED...W wind 10 to 25 kt. Seas 8 ft.
.WED NIGHT...N wind up to 20 kt. Seas 5 to 8 ft.
.THU...NE wind 15 to 30 kt. Seas 6 to 11 ft.
.FRI THROUGH SAT...NW wind 15 to 30 kt. Seas 7 to 12 ft.

$$

PKZ414-180045-
Bering Sea Offshore East of 171W-
326 AM AKDT Tue Oct 17 2017

.TODAY...N wind 15 to 30 kt. Seas 6 to 11 ft.
.TONIGHT...NW wind 20 kt. Seas 6 to 9 ft.
.WED...NW wind 15 to 25 kt. Seas 5 to 9 ft.
.WED NIGHT...NW wind 15 to 30 kt. Seas 6 to 10 ft.
.THU THROUGH SAT...NW wind 10 to 25 kt. Seas 5 to 10 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
446 AM AKDT Mon Oct 16 2017

.ANALYSIS AND UPPER LEVELS...
The remnants of an upper low is over the Kenai Peninsula with a
weak ridge over southwest Alaska. There are some lingering showers
over Prince William Sound and the Gulf Of Alaska. The circulation
of the vortex is discernible from the Middleton Island radar this
morning. There is an upper level low over the northwest Bering
Sea. The jet stream over the northern Pacific continues to barrel
across the region. There is a weak shortwave over the
central/western Aleutians moving rapidly eastward.

&&

.MODEL DISCUSSION...
For the first 24 hr period, the mass fields amongst the
NAM/GFS/ECMWF/GEM are similar. As time elapses, the model
consensus quickly erodes. Compounding the magnitude of the
uncertainty is the fact that the run to run continuity with both
the GFS and the NAM has been below average. The focal point for
this morass is the low that moves over the Aleutians on Tuesday.
The ECMWF brings the track of the low more to the south, while the
Canadian GEM and the GFS are both pinging into a more northerly
track. Additionally, the pace of the storms motion and the
possible development of a triple point low are at stake. While
there is high confidence of another low impacting the North
Pacific and Gulf of Alaska early this week, there is still some
degree of uncertainty about the evolution and the morphology of
the low itself.

&&

.AVIATION...
PANC...VFR conditions and light winds will persist.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...

Partly cloudy to mostly clear skies and cold northerly flow
continue across the mainland will continue through the middle of
the week. A weak vertically stacked low near Middleton Island is
spreading bands of clouds across most of Southcentral Alaska, but
shower activity is confined largely to the north Gulf coast. This
low will drift eastward through tonight, allowing cloudiness to
gradually diminish across most of the forecast area. Gusty
offshore winds will continue around Prince William Sound, with
lighter winds and colder temperatures inland. With clearing skies,
each night is still expected to be a few degrees cooler than the
previous, as a cooler airmass continues to move into the area from
the north. There has been a bit of a shift in the models in
regards to a low moving into the southern Gulf on Tuesday
afternoon. The general trend has been for a slightly stronger and
more northerly track. Thus the morning forecast reflects a bit
more in the way of wind and weather from Kodiak through the
offshore zones. Nevertheless, even with this new trend, the only
impact for the southern mainland will probably be a renewed push
of offshore (northerly) winds by midweek, with plenty of sunshine
to go around.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 3)...

Isolated to scattered rain showers will continue along the
western coast of Alaska through this evening as an area of low
pressure over the Gulf of Anadyr continues to pump moisture
toward Southwest Alaska. As the low pressure system continues to
dissipate this evening, the influx of moisture will likely come to
an end and colder air out of the arctic will descend across
Southwest Alaska. The jet stream will remain well south of
Southwest Alaska which will keep any low pressure systems systems
that develop over the northern Pacific Ocean will quickly be
shunted into the Gulf of Alaska and away from region. Temperatures
will gradually cool off several degrees over the next several
days to more seasonable temperatures.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 through 3)...

An active pattern will be observed along the Aleutian Islands and
southern Bering Sea over the next several days as the jet stream
over the northern Pacific Ocean will spin up multiple low pressure
systems. The first system is an area of low pressure currently
located near Shemya. Based on Satellite imagery, the low is in the
process of intensifying and will track just north of the western
and central Aleutians throughout the day. By tonight, a potent
triple point low looks to spin up not too far from Dutch Harbor
but models are struggling very much with this feature. It's tough
to tell how much impact on winds this feature will have but based
on the jet stream, it looks like the triple point low will
quickly become the dominant low with the low currently near Shemya
fizzling out. Storm force winds and possibly a lightning strike
or two will be possible this afternoon on the back side of the
low. This complex system will quickly move into the Gulf of Alaska
late Tuesday night with multiple low centers as triple point lows
continue to form along the frontal boundary. A separate frontal
boundary will enter the western Bering Sea Wednesday afternoon but
this one should be much weaker than the system currently pushing
through the western Bering Sea.

&&

.LONG TERM FORECAST (Days 3 through 7)...
The mid to long term forecast beginning Tuesday night shows an
active storm track that will primarily stay south of the southern
mainland. This will bring more rain and winds to the Aleutians
through much of the week. There remains disagreement for the
exact track and timing of the low that moves through late in the
week but all guidance keeps it south of the southern mainland
until the weekend. That would leave mainly dry and cold for the
southern mainland until Saturday where there becomes a fair amount
of uncertainty as to what the low will do as it moves toward the
Gulf.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...GALE 174 175 178 413. STORM 176 and 177.

&&

SYNOPSIS AND MODEL DISCUSSION...PJS
SOUTHCENTRAL ALASKA...AD
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MC
LONG TERM...DWK