Gale Warning 571, NWS Anchorage, AK

864 
FZAK61 PAFC 121245
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
345 AM AKST Sun Nov 12 2017

Offshore waters forecast for the Gulf of Alaska West of 144W

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.

PKZ399-130145-
345 AM AKST Sun Nov 12 2017
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 1008 mb low near 59N 144W Sun afternoon will move to 51N 135W 
at 990 mb Mon night. A 995 mb low at 52N 133W will be absorbed by 
the first low on Mon.

$$

PKZ351-130145-
Gulf of Alaska Offshore North of 57N and West of 144W-
345 AM AKST Sun Nov 12 2017

...GALE WARNING TONIGHT...

.TODAY...NW wind 15 to 30 kt. Seas 7 to 11 ft.
.TONIGHT...NW wind 20 to 35 kt becoming N after midnight. Seas 8
to 13 ft.
.MON...N wind 15 to 30 kt. Seas 8 to 12 ft.
.MON NIGHT...N wind 15 to 30 kt. Seas 6 to 11 ft.
.TUE THROUGH THU...NE wind 10 to 25 kt. Seas 4 to 8 ft.

$$

PKZ352-130145-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
345 AM AKST Sun Nov 12 2017

...GALE WARNING TONIGHT AND MONDAY...

.TODAY...NW wind 15 to 30 kt. Seas 7 to 11 ft.
.TONIGHT...NW wind 25 to 35 kt. Seas 9 to 15 ft.
.MON...N wind 25 to 35 kt. Seas 11 to 15 ft.
.MON NIGHT...N wind 20 to 30 kt. Seas 9 to 13 ft.
.TUE THROUGH WED...N wind 15 to 25 kt. Seas 6 to 10 ft.
.THU...NE wind 15 to 30 kt. Seas 6 to 11 ft.

$$

692 
FZAK61 PAFC 130024
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
324 PM AKST Sun Nov 12 2017

Offshore waters forecast for the Gulf of Alaska West of 144W

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.

PKZ399-131400-
324 PM AKST Sun Nov 12 2017
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...
A 1010 mb low at 60N 143W will move to 51N 137W at 990 mb by Mon 
afternoon then it will merge with another 990 mb low near 55N 
140W Tue morning. The low will then move into the southeastern 
Gulf of Alaska by Tue afternoon.

$$

PKZ351-131400-
Gulf of Alaska Offshore North of 57N and West of 144W-
324 PM AKST Sun Nov 12 2017

.TONIGHT...NW to N wind 15 to 30 kt. Seas 7 to 14 ft.
.MON...N wind 15 to 25 kt. Seas 7 to 11 ft.
.MON NIGHT...N wind 10 to 25 kt. Seas 6 to 9 ft.
.TUE...N wind up to 20 kt. Seas 5 to 8 ft.
.TUE NIGHT...N wind up to 20 kt. Seas 4 to 7 ft.
.WED THROUGH FRI...N wind 10 to 25 kt. Seas 3 to 8 ft.

$$

PKZ352-131400-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
324 PM AKST Sun Nov 12 2017

...GALE WARNING TONIGHT...

.TONIGHT...NW wind 20 to 35 kt. Seas building to 9 to 15 ft.
.MON...N wind 20 to 30 kt. Seas 9 to 15 ft.
.MON NIGHT...N wind 20 to 30 kt. Seas 9 to 12 ft.
.TUE...N wind 10 to 25 kt. Seas 7 to 10 ft.
.TUE NIGHT...N wind 10 to 25 kt. Seas 7 ft.
.WED THROUGH FRI...NW wind 15 to 30 kt. Seas 6 to 11 ft.

$$

904 
FZAK61 PAFC 131236
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
336 AM AKST Mon Nov 13 2017

Offshore waters forecast for the Gulf of Alaska West of 144W

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.

PKZ399-140145-
336 AM AKST Mon Nov 13 2017
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 993 mb low at 55N 135W moves to the southeast and exits the Gulf 
Tue night. A 1013 mb low forms at 59N 143W Tue afternoon and remains 
nearly stationary through Tue night at 1014 mb.

$$

PKZ351-140145-
Gulf of Alaska Offshore North of 57N and West of 144W-
336 AM AKST Mon Nov 13 2017

.TODAY...N wind 15 to 25 kt. Seas 7 to 11 ft.
.TONIGHT...N wind 10 to 25 kt. Seas 5 to 10 ft.
.TUE...N wind 10 to 20 kt. Seas 5 to 8 ft.
.TUE NIGHT...N wind up to 20 kt. Seas 4 to 7 ft.
.WED...NW wind up to 15 kt. Seas 3 to 6 ft.
.THU THROUGH FRI...N wind up to 20 kt. Seas 3 to 7 ft.

$$

PKZ352-140145-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
336 AM AKST Mon Nov 13 2017

.TODAY...N wind 20 to 30 kt. Seas 10 to 15 ft.
.TONIGHT...N wind 20 to 30 kt. Seas 10 to 13 ft.
.TUE...N wind 10 to 25 kt. Seas 6 to 11 ft.
.TUE NIGHT...N wind 20 kt. Seas 7 ft.
.WED...NW wind up to 20 kt. Seas 3 to 7 ft.
.THU THROUGH FRI...N wind 15 to 30 kt. Seas 6 to 11 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
451 AM AKST Sat Nov 11 2017

.ANALYSIS AND UPPER LEVELS...

A stagnant, but quite amplified upper level pattern is in place
across Southern Alaska this morning. For Southwest Alaska and the
entirety of the Bering, a sprawling ridge of high pressure and
warm air aloft is in place. For far eastern Alaska, a trough is
slowly departing the area. In between, a strong 125 kt jet is
slowly pushing eastward. The next system and associated shortwave
that will affect the area is exiting eastern Russia. Under the
ridge, fog and/or low stratus is entrenched across much of the
Kuskokwim Delta region, but thus far has not made much progress
to the lee of the Kuskokwim Mountains. Across the Bering, the
center of the surface high is centered west of Dutch Harbor. All
of the flow is northerly across the eastern Bering and the Alaska
Peninsula; whereas broad southerly flow is transporting moisture
into the front coming off of Russia over the western Bering.

For Southcentral, a very wintry air mass is in place, supported by
the light snow pack over much of the area. Thus, the primary
concern is very strong gap wind flows, especially through the
Barrens, Thompson Pass, and the Copper River Delta. The cold air
is being drawn off mainland Alaska into the Gulf around the west
side of a developing low. The cold air picking up moisture from
off the Gulf is causing widespread ocean-effect cloud-bands over
much of the western Gulf.

&&

.MODEL DISCUSSION...

The models remain in excellent agreement through the short-term
forecast as the pattern remains quite steady-state. As such,
continued gap wind flows, the development of a new low over the
north central Gulf Sunday night, and the broad pattern are well
handled, and confidence is high. Where confidence wanes is
concerning the duration and intensity of the expected fog across
Southwest Alaska and Bering, which thus far has been quite
variable. Also, determining when and how strong the strongest
winds through the gaps of Southcentral is also a challenge as the
peaks of the winds coincide with small-scale mountain wave
features not well resolved by any of the models.

&&

.AVIATION...
PANC...VFR conditions will persist. Gusty north winds will persist
through the day, then diminish tonight.

&&

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

Wind. That is the main forecast issue for the next few days. The
gusty winds along the north Gulf coast will weaken a little bit
Saturday night into Sunday before increasing once again. Winds
will mix down along the Copper River and down Cook Inlet as well.

One non-wind question is whether there may be some fog that can
develop in Cook Inlet Saturday night after winds diminish. At this
time it looks like the low-level atmosphere will be sufficiently
dry to discourage it, but it cannot be entirely ruled out.

The gusty winds on the west side of Shelikof Strait are
resuspending some ash from the Katmai/Novarupta eruption from
1912. This ash is expected to diminish this afternoon as winds
will start to diminish some in that area. However, until
sufficient snow cover arrives, resuspended ash is likely to occur
with each bout of strong winds.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
The Southwest remains situated between low pressure to the north
and a ridge to the south through early next week. Influence from
the low to the north brings increased precipitation mainly to the
Kuskokwim Delta and Valley as disturbances dive to the south late
Saturday through Sunday. Fog will be a challenge, especially
along the coastal areas as a stable air mass associated with the
ridge drifts slowly east. Ridging will shift inland Monday into
Tuesday keeping the region in a drier regime heading into the
middle of the next work week.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
Two low pressure systems send multiple fronts toward the Bering
which slowly break the ridge down over the central waters heading
into next week. A subtropical influence brings a warm surge
through the northern Bering which keeps precipitation all rain
with the forthcoming fronts. Gale force winds and moderate rain
are expected along the frontal boundaries as they move through.
The biggest challenge through the next several days is
distinguishing the multiple frontal boundaries as embedded short
waves aloft keeps ongoing precipitation in the short range
forecast as abundant moisture streams up from the Pacific.

&&

.LONG TERM FORECAST (Days 3 through 7)...
From Sunday evening onward, the extended forecast will be
a steady state continuation of the current conditions, mainly dry
and colder across the southern mainland. The dominant feature in
the models is an upper level ridge centered over the Bering Sea.
The next downstream longwave trough is well into the Canadian
Arctic, leaving much of Alaska in northerly jet scenario between
these two features. Several shortwave troughs will come through
the flow within the jet, but any precipitation associated with
them should stay on the windward side of the Alaska Range.
Generally this pattern is a cold and dry one for southcentral
Alaska with gusty gap winds along the coast. Expect high
temperatures in the 20s inland and 30s along the coast with lows
in the single digits and teens. Over the southwest mainland,
fronts coming through the ridge will bring periods of snow and
northwesterly winds.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Gales: 121 127 128 130 131 132 150 175 176 177 185 413

&&

SYNOPSIS AND MODEL DISCUSSION...JPW
SOUTHCENTRAL ALASKA...EZ
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...KH
LONG TERM...ML