Gale Warning 669, NWS Anchorage, AK

340 
FZAK62 PAFC 171239
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
339 AM AKST THU NOV 17 2016

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.

PKZ499-180245-
339 AM AKST THU NOV 17 2016
.SYNOPSIS FOR CENTRAL BERING SEA...
A FRONT EXTENDING ACROSS THE CENTRAL BERING WILL MOVE TO THE
EASTERN BERING BY FRIDAY. A 1009 MB LOW DEVELOPS NEAR 57N 167W
EARLY FRI AND DRIFTS TO 54N 156W WHILE SLOWLY WEAKENING. A 1000
MB NORTH PACIFIC LOW APPROACHES 51N 180W LATE FRI NIGHT.

$$

PKZ411-180245-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE-
339 AM AKST THU NOV 17 2016

...GALE WARNING TODAY...

.TODAY...SW WIND 20 TO 35 KT. SEAS 15 TO 21 FT.
.TONIGHT...SW WIND 30 KT. SEAS 16 TO 20 FT.
.FRI...SW WIND 25 KT. SEAS 12 TO 17 FT.
.FRI NIGHT...SW WIND UP TO 15 KT. SEAS 8 TO 13 FT.
.SAT...N WIND 10 TO 25 KT. SEAS 4 TO 9 FT.
.SUN...NW WIND UP TO 20 KT. SEAS 4 TO 9 FT.
.MON...S WIND 10 TO 20 KT. SEAS 8 TO 16 FT.

$$

PKZ412-180245-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N-
339 AM AKST THU NOV 17 2016

...GALE WARNING TODAY...

.TODAY...S WIND 25 TO 40 KT BECOMING SW 25 KT IN THE
AFTERNOON. SEAS 15 TO 22 FT. RAIN.
.TONIGHT...SW WIND 15 TO 25 KT. SEAS 11 TO 17 FT.
.FRI...SW WIND 15 TO 25 KT. SEAS 11 TO 15 FT.
.FRI NIGHT...SW WIND UP TO 15 KT. SEAS 10 TO 13 FT.
.SAT...E WIND UP TO 20 KT. SEAS 6 TO 9 FT.
.SUN...N WIND 10 TO 20 KT. SEAS 6 TO 9 FT.
.MON...SE WIND UP TO 15 KT. SEAS 3 TO 8 FT.

$$

PKZ413-180245-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N-
339 AM AKST THU NOV 17 2016

...GALE WARNING TODAY...

.TODAY...SW WIND 25 TO 40 KT BECOMING SW 15 TO 25 KT IN THE
AFTERNOON. SEAS 11 TO 19 FT SUBSIDING TO 10 TO 14 FT. RAIN.
.TONIGHT...SW WIND 15 TO 25 KT. SEAS 9 TO 15 FT.
.FRI...SW WIND 25 KT. SEAS 11 TO 15 FT.
.FRI NIGHT...S WIND UP TO 20 KT. SEAS 7 TO 12 FT.
.SAT...NE WIND 10 TO 25 KT. SEAS 5 TO 9 FT.
.SUN...N WIND 10 TO 25 KT. SEAS 5 TO 10 FT.
.MON...SW WIND UP TO 15 KT. SEAS 4 TO 9 FT.

$$

PKZ414-180245-
BERING SEA OFFSHORE EAST OF 171W-
339 AM AKST THU NOV 17 2016

...GALE WARNING TODAY...

.TODAY...SE WIND 20 TO 35 KT. SEAS 8 TO 16 FT. RAIN.
.TONIGHT...S WIND 15 TO 30 KT BECOMING SW 10 TO 20 KT AFTER
MIDNIGHT. SEAS 8 TO 17 FT SUBSIDING TO 8 TO 11 FT.
.FRI...W WIND 10 TO 25 KT. SEAS 7 TO 11 FT.
.FRI NIGHT...W WIND UP TO 15 KT. SEAS 8 TO 11 FT.
.SAT...E WIND 10 TO 25 KT. SEAS 7 FT.
.SUN...NE WIND 10 TO 20 KT. SEAS 4 TO 8 FT.
.MON...NW WIND UP TO 15 KT. SEAS 3 TO 7 FT.

$$

435 
FZAK62 PAFC 180031
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
331 PM AKST THU NOV 17 2016

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.

PKZ499-181445-
331 PM AKST THU NOV 17 2016
.SYNOPSIS FOR CENTRAL BERING SEA...
A FRONT EXTENDING ACROSS THE CENTRAL BERING WILL MOVE TO THE EASTERN
BERING BY FRIDAY. A 1007 MB NORTH PACIFIC MOVES INTO THE CENTRAL
BERING SAT MORNING AT 993 MB. A 993 MB NORTH PACIFIC LOW QUICKLY
MOVES IN BEHIND THIS LOW NEAR 53N 177W AT 989 MB SAT AFTERNOON. A
1000 MB NORTH PACIFIC LOW LATE FRI MOVES TO 53N 163W AT 988 MB SAT
AFTERNOON.

$$

PKZ411-181445-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE-
331 PM AKST THU NOV 17 2016

.TONIGHT...SW WIND 30 KT. SEAS 16 TO 20 FT.
.FRI...SW WIND 25 KT. SEAS 12 TO 17 FT. SNOW SHOWERS.
.FRI NIGHT...S WIND 10 TO 20 KT. SEAS 9 TO 13 FT.
.SAT...NE WIND 15 TO 30 KT. SEAS 5 TO 9 FT.
.SAT NIGHT...NW WIND 10 TO 25 KT. SEAS 5 TO 9 FT.
.SUN...NW WIND UP TO 20 KT. SEAS 4 TO 9 FT.
.MON...S WIND 10 TO 20 KT. SEAS 8 TO 13 FT.
.TUE...SW WIND 15 TO 30 KT. SEAS 14 TO 22 FT.

$$

PKZ412-181445-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N-
331 PM AKST THU NOV 17 2016

.TONIGHT...SW WIND 15 TO 25 KT. SEAS 11 TO 16 FT. RAIN SHOWERS.
.FRI...SW WIND 15 TO 25 KT. SEAS 11 TO 16 FT. RAIN SHOWERS.
.FRI NIGHT...S WIND 10 TO 15 KT. SEAS 12 FT.
.SAT...E WIND UP TO 20 KT. SEAS 7 TO 10 FT.
.SAT NIGHT...NE WIND 10 TO 20 KT. SEAS 7 FT.
.SUN...N WIND 10 TO 20 KT. SEAS 8 FT.
.MON...SE WIND UP TO 20 KT. SEAS 4 TO 9 FT.
.TUE...W WIND UP TO 15 KT. SEAS 8 TO 16 FT.

$$

PKZ413-181445-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N-
331 PM AKST THU NOV 17 2016

.TONIGHT...SW WIND 15 TO 30 KT. SEAS 9 TO 15 FT. RAIN AND SNOW
SHOWERS.
.FRI...SW WIND 25 KT. SEAS 11 TO 15 FT. RAIN AND SNOW SHOWERS.
.FRI NIGHT...S WIND 15 TO 30 KT. SEAS 11 FT.
.SAT...E WIND 15 TO 30 KT. SEAS 7 TO 11 FT.
.SAT NIGHT...NE WIND 15 TO 25 KT. SEAS 7 FT.
.SUN...N WIND 10 TO 25 KT. SEAS 6 TO 10 FT.
.MON...S WIND UP TO 20 KT. SEAS 5 TO 10 FT.
.TUE...W WIND 15 TO 30 KT. SEAS 12 TO 20 FT.

$$

PKZ414-181445-
BERING SEA OFFSHORE EAST OF 171W-
331 PM AKST THU NOV 17 2016

.TONIGHT...SW WIND 20 TO 30 KT. SEAS 8 TO 13 FT. PERIODS OF RAIN.
.FRI...W WIND 15 TO 25 KT. SEAS 7 TO 12 FT. RAIN SHOWERS.
.FRI NIGHT...W WIND 15 KT BECOMING S AFTER MIDNIGHT. SEAS 7 TO
11 FT.
.SAT...E WIND 10 TO 25 KT. SEAS 6 TO 9 FT.
.SAT NIGHT...NE WIND 15 TO 25 KT. SEAS 8 FT.
.SUN THROUGH MON...N WIND UP TO 20 KT. SEAS 4 TO 9 FT.
.TUE...W WIND UP TO 20 KT. SEAS 5 TO 10 FT.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
433 AM AKST Wed Nov 16 2016

.ANALYSIS AND UPPER LEVELS...
There is a closed upper level low positioned over the Upper
Kuskokwim Valley with an associated trough extending southward
through the Alaska and the Aleutian ranges this morning. This
synoptic feature was producing scattered snow showers at
Sparrevohn during the overnight hours last night. While the Copper
River Basin has a ridge of high pressure extending northward into
the North Slope. This feature was aiding in development of fog
during the early morning hours today at Glennallen. Meanwhile, the
western Bering is influenced by an amplified ridge, but an
upstream weather front is approaching the area. The Scatterometer
wind imagery early this morning was showing gale force southerly
winds accompanied by a large swath of moisture streaming through
the Western ALeutians towards the Kamchatka Peninsula. Meanwhile,
the northern Bering has a minor shortwave over the Saint Matthew
Island region extending through the Pribilof Islands. The water
vapor imagery is depicting this feature with drier conditions
behind the shortwave, with a plume of moisture from the
Central/Eastern Aleutians northward into the northern Bering.

&&

.MODEL DISCUSSION...

The models remain in good agreement. The preferred models were the
GFS and the NAM. The models are showing a low developing in the
northern Gulf as it moves westward before being located just south
of Seward by Friday. This coincides with an upper level closed low
that drops down from the north through the Anchorage Bowl before
being positioned over the Kenai. This synoptic feature will remain
under close scrutiny with the potential for snowfall developing
in the Prince William Sound before possibly spilling over into the
Anchorage Bowl by late Friday evening. The forecast confidence
remains average as we head toward the weekend.

&&

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

A few showers remain just south of Middleton Island, but are
continuing to weaken and drift south, as the associated Gulf low
continues to drift to the southeast this morning. Meanwhile high
pressure is building into the Southwest Alaska mainland, which is
supporting gusty northwesterly and northerly flow across western
portions of Southcentral. Winds have increased overnight as the
pressure gradient has increased, which has also helped to mix out
local fog along the Kenai Peninsula and Copper River basin. A vort
max stretched along between these two features is currently
pushing into Southcentral. Although it is a well-defined vort max,
the airmass remains relatively dry, and currently it is expected
only to touch off a few flurries as it drifts across the Talkeetna
and Chugach mountains today. Relatively dry conditions will remain
in place across Southcentral into Thursday as high pressure builds
into the mainland.

&&

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

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
High pressure will sit over the mainland for another day leading
to some of the coldest temperatures of the year, and another
couple days of dry conditions. Morning fog will linger in river
valleys this morning, and should mix out by this afternoon. A
weakening disturbance will spread some middle and high clouds over
the mainland from west to east today before moving out of the area
tonight. Winds will remain relatively light except for some
northerly winds over the eastern Bristol Bay area. Light winds and
clearing sky tonight along with the surface high pressure will
promote another night of fog development, mainly along the
Kuskokwim River. A weakening front approaches the western coast
late Thursday night, bringing a slight chance of rain/snow.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
A storm-force front entering the Western Aleutians/Bering this
morning will progress from west to east as it weakens through late
Thursday night. Rain should be the predominant type along the
front, while cold air filtering into the back side of the system
will promote both rain and snow showers.

&&

.LONG TERM FORECAST (Days 3 through 7)...

It is clear that the Bering ridge,responsible for separating the
two domains into separate weather scenarios, is breaking down.
This will usher in a period of rapidly progressive systems at
least through the middle of next week.

There remains good model agreement Thu night through Fri as the
mainland AK ridge begins to retreat and the Bering front
dissipates over southwest AK and the Akpen. A weak low will also
remain over the extreme northern Gulf. By Fri night the latter low
dissipates, and a succession of lows and waves make their way
across the North Pacific to the Aleutians. This is where the
models have difficulty resolving and moving the lows. Some models
have a series of lows moving east while others consolidate the
features into one large central Aleutian low.

The forecast through Fri night utilized the Nam, but then the
ensemble approach of WPC was used to describe the next low as it
moves, from near Attu on Fri to the central Aleutians on Sat, and
then to the central Gulf on Mon. This low leaves the area on Tue,
while the next low leaves Kamchatka on Mon, reaches the central
Bering Tue, and then continues to the Gulf.

As the lows move east they will spread some rain and snow showers
across the Aleutians and southwest AK. Scattered rain and snow
showers are also expected mainly along the north Gulf coast
through Sat. There should be a break in precipitation beginning Sat
night until it returns with the second low early next week.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Gale 129 173 175-177 185 412-414.
         Storm 178 411
&&

SYNOPSIS AND MODEL DISCUSSION...PLD
SOUTHCENTRAL ALASKA...ELN
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MTL
LONG TERM...DS