Gale Warning 556, NWS Anchorage, AK

306 
FZAK61 PAFC 041058
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
258 AM AKDT Wed Oct 4 2023

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.

PKZ399-050015-
258 AM AKDT Wed Oct 4 2023
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A front extending across the southern Gulf moves to the North 
Gulf Coast for Thu afternoon. 

$$

PKZ351-050015-
Gulf of Alaska Offshore North of 57N and West of 144W-
258 AM AKDT Wed Oct 4 2023

...GALE WARNING TONIGHT...

.TODAY...E wind 10 to 20 kt increasing to 15 to 30 kt in the
afternoon. Seas 5 to 9 ft.
.TONIGHT...SE wind 25 to 40 kt. Seas 9 to 14 ft. Rain.
.THU...S wind 10 to 20 kt. Seas 10 ft.
.THU NIGHT...S wind 15 to 25 kt. Seas 9 to 15 ft.
.FRI THROUGH SAT...SW wind 10 to 20 kt. Seas 6 to 11 ft.
.SUN...SE wind 10 to 20 kt. Seas 5 ft.

$$

PKZ352-050015-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
258 AM AKDT Wed Oct 4 2023

...GALE WARNING THROUGH TONIGHT...

.TODAY...E wind 15 to 30 kt increasing to 25 to 35 kt in the
afternoon. Seas 8 to 13 ft. Rain.
.TONIGHT...SE wind 20 to 35 kt. Seas 10 to 14 ft. Rain.
.THU...S wind 15 to 25 kt. Seas 12 ft.
.THU NIGHT...S wind 15 to 25 kt. Seas 10 to 16 ft.
.FRI THROUGH SUN...S wind up to 20 kt. Seas 6 to 11 ft.

$$

314 
FZAK61 PAFC 042247
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
247 PM AKDT Wed Oct 4 2023

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.

PKZ399-051415-
247 PM AKDT Wed Oct 4 2023
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A front extending across the Southern Gulf moves to the North 
Gulf Coast for Thu afternoon, and dissipates Fri afternoon. 
Several troughs move over the Gulf through Fri afternoon.

$$

PKZ351-051415-
Gulf of Alaska Offshore North of 57N and West of 144W-
247 PM AKDT Wed Oct 4 2023

...GALE WARNING TONIGHT...

.TONIGHT...SE wind 25 to 40 kt. Seas 8 to 13 ft. Rain.
.THU...S wind 10 to 20 kt. Seas 11 ft. Rain.
.THU NIGHT...S wind 20 kt. Seas 11 ft.
.FRI...S wind 10 to 20 kt. Seas 9 to 12 ft.
.FRI NIGHT...SE wind up to 15 kt. Seas 6 to 9 ft.
.SAT THROUGH MON...N wind 10 to 25 kt. Seas 5 to 9 ft.

$$

PKZ352-051415-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
247 PM AKDT Wed Oct 4 2023

...GALE WARNING TONIGHT...

.TONIGHT...SE wind 20 to 35 kt. Seas 10 to 14 ft. Rain.
.THU...S wind 15 to 25 kt. Seas 12 ft. Rain.
.THU NIGHT...S wind 15 to 25 kt. Seas 12 ft.
.FRI...S wind up to 20 kt. Seas 9 to 12 ft.
.FRI NIGHT...S wind up to 15 kt. Seas 7 to 10 ft.
.SAT THROUGH MON...NW wind 15 to 30 kt. Seas 5 to 10 ft.

$$

938 
FZAK61 PAFC 051149
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
349 AM AKDT Thu Oct 5 2023

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.

PKZ399-060030-
349 AM AKDT Thu Oct 5 2023
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A front extending across the southern Gulf moves to the North 
Gulf Coast for Thu afternoon, and dissipates Fri afternoon. 
Several troughs move over the Gulf through Fri afternoon. 

$$

PKZ351-060030-
Gulf of Alaska Offshore North of 57N and West of 144W-
349 AM AKDT Thu Oct 5 2023

.TODAY...S wind 20 kt. Seas 11 ft. Rain.
.TONIGHT...S wind 25 kt. Seas 12 ft.
.FRI...S wind 10 to 20 kt. Seas 10 ft.
.FRI NIGHT...SE wind up to 15 kt. Seas 6 to 9 ft.
.SAT...SW wind up to 20 kt. Seas 5 to 8 ft.
.SUN THROUGH MON...N wind 10 to 25 kt. Seas 5 to 10 ft.

$$

PKZ352-060030-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
349 AM AKDT Thu Oct 5 2023

.TODAY...S wind 15 to 25 kt. Seas 12 ft. Rain.
.TONIGHT...S wind 15 to 25 kt. Seas 10 to 13 ft.
.FRI...S wind 10 to 20 kt. Seas 11 ft.
.FRI NIGHT...S wind up to 15 kt. Seas 7 to 10 ft.
.SAT THROUGH SUN...SW wind up to 20 kt. Seas 6 ft.
.MON...NW wind 15 to 30 kt. Seas 6 to 11 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
507 AM AKDT Tue Oct 3 2023

.ANALYSIS AND UPPER LEVELS...

An upper-level trough and its attendant surface low continue to
track east into the Panhandle. As a result, precipitation tapers
off across eastern Southcentral this morning. High pressure across
the central and eastern Aleutians and Bering, Southwest Alaska,
and much of Southcentral is keeping conditions generally dry and
benign. The pressure gradient between the high pressure to the
west and low pressure to the east has been promoting gusty
northwesterly gap winds along the Alaska Peninsula and through the
Barren Islands. Winds begin to gradually diminish this morning
and will continue to do so during the day. Further west, a
Kamchatka low extends its surface front across the western Bering
and Aleutians. Steady rain and winds up to gale force are
associated with the front.

&&

.MODEL DISCUSSION...

Models remain in good synoptic agreement through most of the
week. There is strong consensus for an upper-level low and surface
front to enter the western Bering and Aleutians this morning. A
surface low will track from the North Pacific into the front and
enhance precipitation for the western and central Aleutians this
afternoon through tonight. Another upper-level low will reach the
Alaska Peninsula and eastern Aleutians Wednesday into Thursday.
Model agreement begins to diverge by Friday and beyond with
regards to the depth and placement of this low, ultimately
affecting precipitation placement and intensity.

&&

.AVIATION...
PANC...VFR will prevail for the TAF period. Light northerly winds
will persist through the day.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3; Today
through Thursday night)...

Snow is slowly coming to an end from west to east across the
Copper River Basin this morning as a compact surface low moves
south of Kayak Island and the upper-level trough slides east
toward the Al-Can border. A drier airmass advecting over
Southcentral in the wake of the aforementioned trough will bring
mostly clear skies and slightly below normal temperatures to much
of the region today through Wednesday. A weak shortwave clipping
the Alaska Range and extreme northern portion of interior
Southcentral this afternoon may bring some clouds and isolated
snow showers to the higher elevations of the Talkeetnas and
Wrangells this afternoon and evening.

The bigger story will be a return to an active weather by the
second half of Wednesday as a North Pacific low pushes its gale-
force front northward over Kodiak Island. Gusty winds and
moderate rain with pockets of heavier precipitation overspread the
island Wednesday afternoon. The front will continue to lift
northward and reach the northern Gulf Coast Thursday morning. In
doing so, an area of northeasterly storm-force winds will be
possible in the vicinity of the Barren Islands Thursday morning,
with easterly and northeasterly gales elsewhere along the north
Gulf Coastal waters. Deep southerly flow and warmer air will
accompany this front. Confidence is high that coastal locations
will see mostly rain with this event. However, there should be
enough cold air in place across the Copper River Basin for at
least a couple of inches of snow before the snow mixes with or
changes over to rain Thursday afternoon. A similar scenario is
also possible for the Susitna Valley; however, there is a higher
level of uncertainty as to how much cold air will be in place at
the start of the event. Currently, it looks like areas around
Willow and Skwentna could see some snow before a changeover to
rain.

&&

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

Mostly dry yet cooler conditions are forecast for Southwest
Alaska over the next few days as weak high pressure gets shunted
from the eastern Bering into the Seward Peninsula through
Wednesday. Below freezing temperatures associated with a polar low
over the Arctic Ocean have spilled all the way into Southwest and
Southcentral. The end result is the first prominent bout of
colder temperatures into Southwest this Fall. Overnight lows
through Wednesday night are forecast to dip into the 20s and 30s,
though daytime highs should warm to above freezing for most areas
each day. Dry weather will last into Wednesday afternoon.
Thereafter, a North Pacific low brings a warm front into Southwest
Alaska late Thursday along with a plume of deep moisture. Showers
are forecast to spread northward across Southwest throughout the
day on Thursday as the front makes a trip to the Arctic Circle.

Across the Bering an occluded front is overspreading the Western
Aleutians this morning. Southerly gales and numerous showers will
linger through late Tuesday while also moving into the Central
Aleutians. Enhanced winds with potential storm force gusts will
taper off early Wednesday morning as the front is carried
northwestward into Kamchatka and its parent low begins to shear
apart over the Western Aleutians. Late on Wednesday will see
redevelopment of potential gales, this time along the Alaska
Peninsula as the N Pacific low moves from the Pacific side of the
AKPEN into Bristol Bay.

&&

.LONG TERM FORECAST (Days 4 through 7: Friday through Monday)...

An upper-level longwave trough, with embedded closed low centers,
will remain in place across southern mainland Alaska for the long
term forecast period. At the surface, model guidance suggests
this corresponds to a broad low pressure centered near the Alaska
Peninsula gradually shifting into the Gulf of Alaska. However, the
surface details are highly uncertain, with different model
solutions depicting differing low strengths and various individual
waves propagating through the flow.

At the beginning of the long term on Friday, a low centered over
the Alaska Peninsula is accompanied by a front spreading
precipitation across much of southern mainland Alaska, while northeasterly
winds are drawn from Interior Alaska out across the Kuskokwim
Delta. These winds are a point of disagreement in the model
guidance, as a result of uncertain strength in the pressure
gradient between the Alaska Peninsula low and high pressure over
the Chukchi Sea. As a result, while strong northeasterly winds are
likely to set up through the Kuskokwim Delta, there is moderate
uncertainty in what their intensity will be. Low end guidance
suggests sustained winds peak out near 25 mph, while the higher
end suggests gale force winds (>39 mph) are possible. The current
forecast favors the mid to higher end of this range.

Northeasterly winds flow out across much of the Bering Sea for
the end of the week, before a ridge moves in from the west and low
pressure shifts into the Gulf by Sunday. This reorients the winds
more northerly, while they become more limited to the eastern
Bering Sea, but affect a greater portion of Southwest Alaska. The
front over southern mainland Alaska weakens, leading to more
showery conditions, while southerly onshore flow continues to
wring out precipitation along the coast from Kodiak to Cape
Suckling through Sunday. The front may linger over Southcentral as
it pivots in response to an Arctic trough dipping southward
across Southwest Alaska. Model inconsistencies abound, so
generally expect continued above seasonal normal rain chances,
with no particular geographical focus among inland locations.

For Monday, there is moderate potential for winds out of gaps
along the Alaska Peninsula and western Gulf coast as low pressure
increasingly focuses in the Gulf and cold air looks to push south
across the Aleutian Range. Models also generally indicate a weak
(below gale force), disorganized low entering the western Bering
Sea at the start of next week.

&&

SYNOPSIS AND MODEL DISCUSSION...AF
SOUTHCENTRAL ALASKA...TM
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...BL
LONG TERM...CQ