Small Craft Advisory 766, NWS Anchorage, AK

607 
FZAK52 PAFC 292224
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
Issued by National Weather Service Fairbanks AK
224 PM AKDT Wed Sep 29 2021

Coastal Waters Forecast for Southwest Alaska+Bristol Bay+The
Alaska Peninsula Waters and the Aleutian Islands up to 100 nm out.

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.

PKZ199-301100-
224 PM AKDT Wed Sep 29 2021
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 972 mb low 200 NM NW of Saint Matthew Island will move to 400 NM N
of Atka as a 980 mb low by 4am Thu. By 4pm Thu, the low moves to 100
NM NW of Nikolski at 991 mb. An additional 1000 mb low will move to 
400 NM SE of Atka by 4pm Thu.

$$

PKZ150-301100-
South of the AK Peninsula Sitkinak to Castle Cape-
224 PM AKDT Wed Sep 29 2021

...GALE WARNING THROUGH THURSDAY...

.TONIGHT...SW wind 25 kt increasing to 35 kt after midnight. Seas
8 ft building to 13 ft after midnight. Rain showers.
.THU...W wind 45 kt. Seas 20 ft. Rain showers.
.THU NIGHT...W wind 30 kt diminishing to 20 kt after midnight.
Seas 15 ft subsiding to 10 ft after midnight.
.FRI AND FRI NIGHT...NW wind 35 kt. Seas 13 ft.
.SAT...NW wind 35 kt. Seas 14 ft.
.SUN...NW wind 30 kt. Seas 11 ft.
.MON...S wind 20 kt. Seas 8 ft.

$$

PKZ155-301100-
South of the AK Peninsula Castle Cape to Cape Sarichef-
224 PM AKDT Wed Sep 29 2021

...GALE WARNING THROUGH THURSDAY...

.TONIGHT...W wind 40 kt. Seas 17 ft. Rain showers.
.THU...W wind 40 kt. Seas 18 ft. Rain showers.
.THU NIGHT...NW wind 30 kt except W 25 kt from the Shumagin
Islands E. Seas 13 ft.
.FRI...NW wind 30 kt. Seas 12 ft.
.FRI NIGHT...NW wind 35 kt. Seas 13 ft.
.SAT...NW wind 35 kt. Seas 13 ft.
.SUN...W wind 30 kt. Seas 9 ft.
.MON...S wind 25 kt. Seas 16 ft.

$$

PKZ160-301100-
Bristol Bay-
224 PM AKDT Wed Sep 29 2021

...SMALL CRAFT ADVISORY THROUGH THURSDAY NIGHT...

.TONIGHT...SW wind 30 kt. Seas 9 ft. Rain showers.
.THU...W wind 30 kt. Seas 12 ft. Rain showers.
.THU NIGHT...W wind 25 kt. Seas 9 ft.
.FRI...NW wind 30 kt. Seas 10 ft.
.FRI NIGHT...NW wind 35 kt. Seas 12 ft.
.SAT...NW wind 35 kt. Seas 12 ft.
.SUN...NW wind 25 kt. Seas 8 ft.
.MON...SE wind 25 kt. Seas 6 ft.

$$

PKZ165-301100-
Port Heiden to Cape Sarichef-
224 PM AKDT Wed Sep 29 2021

...GALE WARNING THROUGH THURSDAY...

.TONIGHT...SW wind 35 kt becoming W 45 kt after midnight. Seas 14 ft
building to 20 ft after midnight. Rain showers.
.THU...W wind 45 kt diminishing to 30 kt in the afternoon. Seas
18 ft. Rain showers.
.THU NIGHT...NW wind 20 kt increasing to 30 kt after midnight.
Seas 15 ft.
.FRI...NW wind 30 kt. Seas 15 ft.
.FRI NIGHT...NW wind 35 kt. Seas 17 ft.
.SAT...NW wind 35 kt. Seas 15 ft.
.SUN...W wind 25 kt. Seas 9 ft.
.MON...S wind 30 kt. Seas 13 ft.

$$

PKZ170-301100-
Cape Sarichef to Nikolski Bering Side-
224 PM AKDT Wed Sep 29 2021

...GALE WARNING THROUGH THURSDAY...

.TONIGHT...W wind 40 kt. Seas 21 ft. Rain showers.
.THU...W wind 40 kt. Seas 21 ft. Rain showers.
.THU NIGHT...NW wind 30 kt. Seas 17 ft.
.FRI AND FRI NIGHT...NW wind 30 kt. Seas 15 ft.
.SAT...NW wind 30 kt. Seas 13 ft.
.SUN...SW wind 30 kt. Seas 10 ft.
.MON...S wind 30 kt. Seas 28 ft.

$$

PKZ171-301100-
Unalaska Bay-
224 PM AKDT Wed Sep 29 2021

...GALE WARNING THROUGH THURSDAY...

.TONIGHT...W wind 30 kt increasing to 40 kt after midnight. Seas
5 ft. Rain showers.
.THU...W wind 35 kt. Seas 5 ft. Rain showers.
.THU NIGHT...NW wind 30 kt. Seas 11 ft.
.FRI AND FRI NIGHT...NW wind 30 kt. Seas 11 ft.
.SAT...NW wind 25 kt. Seas 9 ft.
.SUN...SW wind 15 kt. Seas 2 ft.
.MON...S wind 25 kt. Seas 4 ft.

$$

PKZ172-301100-
Cape Sarichef to Nikolski Pacific Side-
224 PM AKDT Wed Sep 29 2021

...GALE WARNING THROUGH THURSDAY...

.TONIGHT...SW wind 40 kt. Seas 17 ft. Rain showers.
.THU...W wind 35 kt. Seas 14 ft.
.THU NIGHT...W wind 30 kt. Seas 12 ft.
.FRI AND FRI NIGHT...NW wind 30 kt. Seas 11 ft.
.SAT...NW wind 30 kt. Seas 10 ft.
.SUN...SW wind 25 kt. Seas 10 ft.
.MON...S wind 30 kt. Seas 26 ft.

$$

PKZ173-301100-
Nikolski to Seguam Island Bering Side-
224 PM AKDT Wed Sep 29 2021

...GALE WARNING THROUGH THURSDAY NIGHT...

.TONIGHT...W wind 35 kt. Seas 20 ft. Rain showers.
.THU...W wind 35 kt increasing to 45 kt in the afternoon. Seas
24 ft.
.THU NIGHT...N wind 35 kt diminishing to 25 kt after midnight.
Seas 21 ft.
.FRI AND FRI NIGHT...NW wind 25 kt. Seas 13 ft.
.SAT...W wind 20 kt. Seas 10 ft.
.SUN...S wind 30 kt. Seas 15 ft.
.MON...S wind 30 kt. Seas 34 ft.

$$

PKZ174-301100-
Nikolski to Seguam Island Pacific Side-
224 PM AKDT Wed Sep 29 2021

...GALE WARNING THROUGH THURSDAY NIGHT...

.TONIGHT...W wind 35 kt. Seas 16 ft. Rain.
.THU...W wind 30 kt increasing to 40 kt in the afternoon. Seas
16 ft.
.THU NIGHT...NW wind 40 kt becoming N 30 kt after midnight. Seas
19 ft.
.FRI AND FRI NIGHT...NW wind 25 kt. Seas 11 ft.
.SAT...NW wind 20 kt. Seas 9 ft.
.SUN...S wind 30 kt. Seas 16 ft.
.MON...SW wind 30 kt. Seas 31 ft.

$$

PKZ175-301100-
Seguam Island to Adak Bering Side-
224 PM AKDT Wed Sep 29 2021

...GALE WARNING THROUGH THURSDAY...

.TONIGHT...W wind 35 kt. Seas 18 ft.
.THU...W wind 40 kt. Seas 22 ft.
.THU NIGHT...N wind 30 kt diminishing to 20 kt after midnight.
Seas 20 ft subsiding to 14 ft after midnight.
.FRI AND FRI NIGHT...N wind 20 kt. Seas 11 ft.
.SAT...SW wind 15 kt. Seas 9 ft.
.SUN...S wind 30 kt. Seas 21 ft.
.MON...SW wind 35 kt. Seas 32 ft.

$$

PKZ176-301100-
Seguam Island to Adak Pacific Side-
224 PM AKDT Wed Sep 29 2021

...GALE WARNING THROUGH THURSDAY NIGHT...

.TONIGHT...W wind 35 kt becoming NW 25 kt after midnight. Seas
14 ft. Rain.
.THU...NW wind 25 kt increasing to 35 kt in the afternoon. Seas
12 ft.
.THU NIGHT...N wind 35 kt diminishing to 25 kt after midnight.
Seas 13 ft.
.FRI AND FRI NIGHT...N wind 20 kt. Seas 8 ft.
.SAT...SW wind 20 kt. Seas 7 ft.
.SUN...S wind 30 kt. Seas 25 ft.
.MON...SW wind 30 kt. Seas 30 ft.

$$

PKZ177-301100-
Adak to Kiska-
224 PM AKDT Wed Sep 29 2021

...SMALL CRAFT ADVISORY THROUGH THURSDAY NIGHT...

.TONIGHT...NW wind 30 kt. Seas 16 ft Bering side...12 ft Pacific 
side.
.THU...NW wind 30 kt. Seas 17 ft Bering side...11 ft Pacific side.
.THU NIGHT...N wind 25 kt. Seas 15 ft.
.FRI...N wind 15 kt. Seas 10 ft.
.FRI NIGHT...Variable wind 10 kt. Seas 7 ft.
.SAT...SE wind 25 kt. Seas 8 ft.
.SUN...S wind 35 kt. Seas 28 ft.
.MON...SW wind 40 kt. Seas 28 ft.

$$

PKZ178-301100-
Kiska to Attu-
224 PM AKDT Wed Sep 29 2021

...SMALL CRAFT ADVISORY THROUGH THURSDAY NIGHT...

.TONIGHT...N wind 25 kt. Seas 12 ft.
.THU...N wind 30 kt. Seas 13 ft.
.THU NIGHT...N wind 25 kt. Seas 12 ft.
.FRI...NE wind 15 kt. Seas 8 ft.
.FRI NIGHT...SE wind 15 kt. Seas 6 ft.
.SAT...SE wind 30 kt. Seas 9 ft.
.SUN...S wind 40 kt. Seas 26 ft.
.MON...SW wind 40 kt. Seas 26 ft.

$$

PKZ179-301100-
Pribilof Islands Near Shore Waters-
224 PM AKDT Wed Sep 29 2021

...GALE WARNING TONIGHT...

.TONIGHT...W wind 40 kt. Seas 17 ft. Rain showers.
.THU...NW wind 30 kt. Seas 17 ft.
.THU NIGHT...N wind 30 kt. Seas 15 ft.
.FRI AND FRI NIGHT...NW wind 30 kt. Seas 13 ft.
.SAT...W wind 25 kt. Seas 10 ft.
.SUN...SW wind 30 kt. Seas 10 ft.
.MON...S wind 30 kt. Seas 22 ft.

$$

PKZ180-301100-
Kuskokwim Delta and Etolin Strait-
224 PM AKDT Wed Sep 29 2021

...SMALL CRAFT ADVISORY THROUGH THURSDAY NIGHT...

.TONIGHT...S wind 30 kt becoming W after midnight. Seas 10 ft. Rain showers.
.THU...W wind 30 kt. Seas 13 ft.
.THU NIGHT...N wind 30 kt. Seas 12 ft.
.FRI AND FRI NIGHT...NW wind 35 kt. Seas 14 ft.
.SAT...NW wind 30 kt. Seas 13 ft.
.SUN...W wind 25 kt. Seas 7 ft.
.MON...SE wind 30 kt. Seas 13 ft.

$$

PKZ181-301100-
North and West of Nunivak Island-
224 PM AKDT Wed Sep 29 2021

...GALE WARNING THROUGH THURSDAY...

.TONIGHT...S wind 35 kt becoming N after midnight. Seas 11 ft. Rain.
.THU...N wind 35 kt. Seas 14 ft. Rain.
.THU NIGHT...N wind 30 kt. Seas 14 ft.
.FRI AND FRI NIGHT...NW wind 35 kt. Seas 14 ft.
.SAT...NW wind 30 kt. Seas 10 ft.
.SUN...S wind 25 kt. Seas 6 ft.
.MON...SE wind 30 kt. Seas 13 ft.

$$

PKZ185-301100-
Saint Matthew Island Waters-
224 PM AKDT Wed Sep 29 2021

...GALE WARNING THROUGH THURSDAY...

.TONIGHT...E of Saint Matthew Island, W wind 35 kt becoming NW 20 kt
after midnight. W of Saint Matthew Island, W wind 45 kt. Seas 24 ft.
.THU...N wind 40 kt diminishing to 30 kt in the afternoon. Seas 18 ft.
.THU NIGHT...N wind 30 kt. Seas 14 ft.
.FRI AND FRI NIGHT...NW wind 30 kt. Seas 12 ft.
.SAT...SW wind 25 kt. Seas 8 ft.
.SUN...S wind 30 kt. Seas 13 ft.
.MON...E wind 30 kt. Seas 20 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion...CORRECTED
National Weather Service Anchorage AK
523 PM AKDT Tue Sep 28 2021

.ANALYSIS AND UPPER LEVELS...

A stacked low continues to slide across the Gulf of Alaska this
afternoon and weaken. Mainly clear skies can be seen from the
Cooper River region, west towards Anchorage and into the MatSu
Valley. Solar radiation is still strong enough that temperatures
across lower elevation regions are in the 40s, a great rebound
from the morning teens to low 20s. Out west, winds are increasing
out of the west to northwest in the Bering. This area lay
sandwiched between high pressure to the southwest and a deepening
low pressure system that is developing on the eastern tip of
Siberia.

&&

.MODEL DISCUSSION...

Synoptically speaking, models are in great agreement through about
54 hours today. As the polar jet is forecast to intensify as it
drops out of Siberia, the core of an upper level low will get
pulled off of the jet and stall near Cook Inlet. A new and
stronger low will develop near the tip of the exit region of the
polar jet. It is expected to rapidly intensify as it moves into
the Gulf of Alaska. This is where the theme of the models remains:
There will be an unusually strong low somewhere in the Gulf Friday
night into Saturday morning. This theme and the overall
inconsistencies have remained constant over these past few days.
The Canadian was the deepest and farthest north solution,
skirting Prince William Sound at 960 MB. The European is a
little more sensible and about 250 miles east at the same depth
-Saturday morning. By Sunday, the chaos in the models is resolved
as all guidance continues to weaken the stacked low to the east of
Kodiak. Regardless, seeing sub 950mb low in the Gulf of Alaska
this early in the season quite a sight to behold!

&&

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

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3: Today
through Friday afternoon)...

In the coming days, Southcentral will be impacted by two lows
moving through the Gulf. The first low is currently in the Gulf
and will linger through Thursday. With high pressure inland and
low pressure in the Gulf, a pressure gradient near the coast will
drive gusty winds through Thompson Pass, Resurrection Bay, and
the Copper River Delta on Wednesday. As the low stays further
offshore, skies will be sunny and clear for much of Southcentral.
This will allow temperatures to drop below freezing for much of
the interior tonight and Wednesday night.

Cloud cover increases into Thursday. The lingering Gulf low will
bring rain into the Copper River Basin and Western Prince William
Sound through Thursday. At the same time, another low enters the
Gulf from the Bering. Its front progresses eastward through the
day Thursday, bringing rain to much of Southcentral except for
some areas of downsloping on the Eastern Kenai Peninsula and
Anchorage. While uncertainty remains with the track and
interaction of lows in the Gulf on Friday, Southcentral will
see unsettled conditions.

&&

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

A shortwave trough will move onshore over the Y-K Delta overnight
tonight, bringing in a round of showers inland as it tracks from
west to east. Temperatures should be warm enough to keep
precipitation mainly in the form of rain at low elevations near
the coast, though mixing with or even a changeover to snow is
possible over the Y-K Delta with an initial wave of showers
already beginning to move inland through tonight. Most areas east
of the Kuskokwim Mountains will remain dry, with the trough mostly
shearing out as it moves towards the Middle Kuskokwim Valley on
Wednesday morning.

On Wednesday afternoon, a developing Hurricane force low in the
northern Bering will send an initially strong front into the
Southwest coast. Southeast winds will pick up ahead of the front
near the coastline, with gusts up to 40 mph possible on Wednesday
evening. A band of moderate rainfall will move inland with the
weakening front as a triple-point low develops and moves into
Bristol Bay early on Thursday morning, with enough cold air
remaining intact over the Southwest interior to allow for
snowfall, particularly over higher elevations over and near the
Kuskokwim Mountains and Alaska Range. Minor wet snow
accumulations generally under 1 inch are possible at lower
elevations on Thursday, including near Bethel and Aniak. Rainfall
amounts along the coast will add up to around 0.5 to 1 inch
between Wednesday evening and Thursday afternoon.

The complex low and frontal system will move east into the Gulf on
Friday, initiating a cold, northerly flow that will drop
temperatures back well below freezing for most of the region.
Morning lows will drop into the 10s to 20s inland, with daytime
highs only making it to the mid to upper 30s on Friday afternoon.

&&

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

A powerful low pressure system will develop over the northern
Bering late tonight into Wednesday as a Polar low merges with a
shortwave trough ejecting from the Kamchatka Peninsula. A surface
low will deepen rapidly down to 970 mb by early Wednesday
afternoon, stalling out as it reaches its maturing stage just
northwest of St Matthew Island. A conveyor of modified Arctic air
will wrap around the low from the northwest, combining with a very
tight pressure gradient and low level instability to support a
corridor of Hurricane force winds on the southwest side of the
low. These winds will remain over open waters to the west of St
Matthew Island, mainly on Wednesday afternoon and evening.

Forecast uncertainty increases as the occluding center begins a
southward dive towards the Pribilofs and Eastern Aleutians on
Thursday, with storm force winds continuing to follow south and
west of the center over open waters of the central and western
Bering. Models still show a range of outcomes for the low track,
with the center possibly crossing the Aleutian Chain or southern
AKPen as far west as Nikolski or as far east as Cold Bay on
Thursday afternoon. Very strong and gusty west to northwest winds
will move across the aleutians near and just west of where the
center crosses into the North Pacific, with gusts in excess of 60
mph possible at the peak of the event. Areas between Nikolski and
Dutch Harbor are currently most favored for seeing higher wind
gusts, though this remains subject to change with the growing
uncertainty for the low track by Thursday afternoon and evening.
Those with interests along the Eastern Aleutians should continue
to monitor the forecast closely for possible weather headlines for
strong wind as the evolution and track for this low become better
resolved.

&&
.MARINE (Days 3 through 5: Friday through Sunday)...

A weakening low crosses the AKPen and eastern Aleutians into the
Gulf Friday morning. A swath of gales close to the center of the
low and south of the AKPen diminishes through the morning. Another
low near the Barren Islands produces a brief swath of gales south
of the Kenai Peninsula before diminishing through Friday morning.
Seas on the Pacific/Gulf side will remain below 20 ft with these
systems. A new low enters the Gulf from the North Pacific Friday
evening, with the potential to develop storm-force winds wrapping
the center and widespread gales Friday evening through Saturday
morning. Seas may reach 20 to 30 ft, particularly east of the low
center in the central or eastern Gulf, depending on low track.
Gusty gap winds approaching storm force off the AKPen and western
Gulf develop Friday night into Saturday morning. Winds diminish
and seas subside late Saturday into Sunday. Seas 20 to 30 ft are
possible as another low enters the western Bering on Sunday.
Widespread gales are likely through the western Aleutians and
western Bering through Sunday night with storm-force winds
possible concentrated near the low center.

.Long Term Discussion (Days 4 through 7: Saturday through Tuesday)...

A progressive amplified pattern is expected through Tuesday,
beginning with an upper-level trough situated over mainland
Alaska and the Gulf on Saturday. A shortwave at the base of this
trough supports the genesis of a potentially strong cyclone moving
northward in the Gulf early Saturday morning. Global models
continue to vary with the track of this system and solutions have
trended eastward today. As a result, impacts may be more limited
to the marine and coastal areas, with gap winds in the western
Gulf and precipitation along the north Gulf coast being the main
concerns. The EC and Canadian support this idea, being the
furthest east, and push the cyclone ashore near Yakutat with the
low rapidly weakening and the front moving inland quickly. The GFS
instead depicts a slower northward progression of the front and
hooks the low westward toward Prince William Sound, which would
produce more significant wind impacts along the coast and higher
potential for rain and snow inland over Southcentral. In either
case, with a closed upper-level low expected to remain over
Southcentral and the Gulf through Sunday, unsettled, cloudy
weather with chances for rain and snow flurries will remain
favored.

A strong shortwave ridge pushes eastward across the Bering ahead
of the extratropical remnants of Typhoon Mindulle entering the
western Bering on Sunday. High winds, up to storm-force, and rough
seas are expected with this low as it tracks into the central
Bering through Tuesday. Global models have been fairly consistent
with a minimum central pressure somewhere around the 950s in mb on
Monday over the western Bering. Ridging moves in over mainland
Alaska briefly on Monday before a front associated with the Bering
low moves ashore over Southwest Alaska and the AKPen, bringing
precipitation and windy conditions Monday night through Tuesday.

&&
.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Hurricane Wind Warning 185.
 		 Storm Warning 411-413.
	     Gale Warning 150, 155, 165, 170-181, 414.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...SS
SOUTHCENTRAL ALASKA...AP/KC
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...AS
MARINE/LONG TERM...CQ