Storm Warning 170, NWS Anchorage, AK

564 
FZAK52 PAFC 201241
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
341 AM AKST Fri Nov 20 2020

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.

PKZ199-210145-
341 AM AKST Fri Nov 20 2020
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 969 mb low 245 nm southwest of Dillingham this morning will 
move 280 nm northwest of Bethel at 968 mb Saturday morning. The 
low then moves into eastern Siberia at 973 mb Sunday morning. 

$$

PKZ150-210145-
South of the AK Peninsula Sitkinak to Castle Cape-
341 AM AKST Fri Nov 20 2020

...STORM WARNING TODAY...

.TODAY...SE wind 50 kt becoming SW 30 kt in the afternoon. Seas 22 ft
subsiding to 16 ft in the afternoon. Rain.
.TONIGHT...W wind 30 kt. Seas 16 ft.
.SAT...W wind 30 kt. Seas 14 ft.
.SAT NIGHT...SW wind 20 kt. Seas 11 ft.
.SUN...SE wind 50 kt. Seas 17 ft.
.MON...W wind 50 kt. Seas 22 ft.
.TUE...SW wind 35 kt. Seas 16 ft.

$$

PKZ155-210145-
South of the AK Peninsula Castle Cape to Cape Sarichef-
341 AM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TODAY...W wind 30 kt. Seas 18 ft. Rain with snow showers.
.TONIGHT...W wind 30 kt. Seas 17 ft. Rain showers and snow showers.
.SAT...W wind 25 kt. Seas 13 ft. Rain showers.
.SAT NIGHT...S wind 20 kt. Seas 9 ft.
.SUN THROUGH MON...W wind 45 kt. Seas 18 ft.
.TUE...S wind 40 kt. Seas 22 ft.

$$

PKZ160-210145-
Bristol Bay-
341 AM AKST Fri Nov 20 2020

...STORM WARNING TODAY...

.TODAY...E wind 50 kt becoming SE 40 kt in the afternoon. Seas
13 ft. Rain with snow.
.TONIGHT...S wind 25 kt. Seas 9 ft.
.SAT...W wind 25 kt. Seas 9 ft.
.SAT NIGHT...SW wind 20 kt. Seas 7 ft.
.SUN...NE wind 30 kt. Seas 8 ft.
.MON...W wind 35 kt. Seas 10 ft.
.TUE...S wind 30 kt. Seas 8 ft.

$$

PKZ165-210145-
Port Heiden to Cape Sarichef-
341 AM AKST Fri Nov 20 2020

...GALE WARNING THROUGH TONIGHT...

.TODAY...SW wind 40 kt except SW 30 kt from Port Moller E. Seas
22 ft except 15 ft from Port Moller E. Rain showers and snow showers.
.TONIGHT...W wind 35 kt. Seas 21 ft. Rain showers and snow showers.
.SAT...W wind 25 kt. Seas 16 ft.
.SAT NIGHT...S wind 20 kt. Seas 11 ft.
.SUN...N wind 40 kt. Seas 13 ft.
.MON...W wind 40 kt. Seas 13 ft.
.TUE...S wind 35 kt. Seas 14 ft.

$$

PKZ170-210145-
Cape Sarichef to Nikolski Bering Side-
341 AM AKST Fri Nov 20 2020

...GALE WARNING THROUGH TONIGHT...

.TODAY...W wind 40 kt. Seas 21 ft. Snow showers and rain showers.
.TONIGHT...W wind 35 kt. Seas 19 ft.
.SAT...W wind 25 kt. Seas 14 ft.
.SAT NIGHT...SE wind 20 kt. Seas 10 ft.
.SUN...NW wind 40 kt. Seas 14 ft.
.MON THROUGH TUE...S wind 40 kt. Seas 15 ft.

$$

PKZ171-210145-
Unalaska Bay-
341 AM AKST Fri Nov 20 2020

...GALE WARNING TODAY...

.TODAY...W wind 35 kt. Seas 5 ft. Rain showers and snow showers.
.TONIGHT...W wind 30 kt diminishing to 20 kt after midnight. Seas
5 ft subsiding to 3 ft after midnight.
.SAT...W wind 15 kt becoming SW in the afternoon. Seas 2 ft.
.SAT NIGHT...SE wind 15 kt. Seas 2 ft.
.SUN...NW wind 30 kt. Seas 9 ft.
.MON...SW wind 30 kt. Seas 5 ft.
.TUE...S wind 25 kt. Seas 4 ft.

$$

PKZ172-210145-
Cape Sarichef to Nikolski Pacific Side-
341 AM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TODAY...W wind 30 kt. Seas 16 ft. Snow showers and rain showers.
.TONIGHT...W wind 30 kt. Seas 15 ft. Rain showers.
.SAT...W wind 20 kt. Seas 11 ft.
.SAT NIGHT...SE wind 20 kt. Seas 8 ft.
.SUN...NW wind 40 kt. Seas 17 ft.
.MON...SW wind 40 kt. Seas 16 ft.
.TUE...S wind 40 kt. Seas 23 ft.

$$

PKZ173-210145-
Nikolski to Seguam Island Bering Side-
341 AM AKST Fri Nov 20 2020

...GALE WARNING TODAY...

.TODAY...W wind 35 kt. Seas 16 ft.
.TONIGHT...W wind 25 kt. Seas 14 ft.
.SAT...W wind 20 kt. Seas 10 ft.
.SAT NIGHT...NE wind 20 kt. Seas 8 ft.
.SUN...NW wind 30 kt. Seas 13 ft.
.MON THROUGH TUE...SW wind 40 kt. Seas 20 ft.

$$

PKZ174-210145-
Nikolski to Seguam Island Pacific Side-
341 AM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TODAY...W wind 30 kt. Seas 17 ft.
.TONIGHT...W wind 25 kt. Seas 15 ft.
.SAT...W wind 20 kt. Seas 11 ft.
.SAT NIGHT...E wind 25 kt. Seas 10 ft.
.SUN...NW wind 35 kt. Seas 16 ft.
.MON THROUGH TUE...SW wind 40 kt. Seas 22 ft.

$$

PKZ175-210145-
Seguam Island to Adak Bering Side-
341 AM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TODAY...W wind 30 kt. Seas 13 ft. Snow showers.
.TONIGHT...W wind 20 kt. Seas 10 ft.
.SAT...W wind 20 kt in the morning becoming variable 10 kt. Seas
8 ft.
.SAT NIGHT...N wind 20 kt. Seas 6 ft.
.SUN...W wind 30 kt. Seas 12 ft.
.MON...S wind 40 kt. Seas 17 ft.
.TUE...SW wind 40 kt. Seas 17 ft.

$$

PKZ176-210145-
Seguam Island to Adak Pacific Side-
341 AM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TODAY...W wind 30 kt. Seas 16 ft. Snow showers.
.TONIGHT...W wind 20 kt. Seas 12 ft.
.SAT...W wind 15 kt in the morning becoming variable 10 kt. Seas
10 ft.
.SAT NIGHT...NE wind 25 kt. Seas 11 ft.
.SUN...W wind 30 kt. Seas 13 ft.
.MON...S wind 40 kt. Seas 25 ft.
.TUE...SW wind 40 kt. Seas 25 ft.

$$

PKZ177-210145-
Adak to Kiska-
341 AM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TODAY...W wind 25 kt. Seas 15 ft.
.TONIGHT...W wind 20 kt. Seas 11 ft.
.SAT...W wind 15 kt. Seas 8 ft.
.SAT NIGHT...N wind 20 kt. Seas 9 ft.
.SUN...W wind 35 kt. Seas 12 ft.
.MON...S wind 45 kt. Seas 24 ft.
.TUE...SW wind 35 kt. Seas 21 ft.

$$

PKZ178-210145-
Kiska to Attu-
341 AM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH TONIGHT...

.TODAY...W wind 25 kt. Seas 14 ft.
.TONIGHT...NW wind 15 kt. Seas 10 ft.
.SAT...NW wind 15 kt. Seas 7 ft.
.SAT NIGHT...NW wind 20 kt. Seas 8 ft.
.SUN...SW wind 40 kt. Seas 18 ft.
.MON...SW wind 40 kt. Seas 24 ft.
.TUE...SW wind 35 kt. Seas 20 ft.

$$

PKZ179-210145-
Pribilof Islands Near Shore Waters-
341 AM AKST Fri Nov 20 2020

...GALE WARNING THROUGH TONIGHT...

.TODAY...W wind 40 kt. Seas 17 ft. Rain showers and snow showers.
.TONIGHT...W wind 40 kt. Seas 18 ft.
.SAT...W wind 30 kt. Seas 15 ft.
.SAT NIGHT...SW wind 20 kt. Seas 12 ft.
.SUN...W wind 35 kt. Seas 14 ft.
.MON THROUGH TUE...SW wind 35 kt. Seas 21 ft.

$$

PKZ180-210145-
Kuskokwim Delta and Etolin Strait-
341 AM AKST Fri Nov 20 2020

...STORM WARNING TODAY...

.TODAY...SE wind 50 kt diminishing to 40 kt in the afternoon. Seas
14 ft. Rain and snow.
.TONIGHT...SE wind 30 kt. Seas 13 ft. Rain.
.SAT...SW wind 25 kt. Seas 13 ft.
.SAT NIGHT...SW wind 20 kt. Seas 10 ft.
.SUN...NW wind 30 kt. Seas 8 ft.
.MON...W wind 30 kt. Seas 9 ft.
.TUE...S wind 30 kt. Seas 14 ft.

$$

PKZ181-210145-
North and West of Nunivak Island-
341 AM AKST Fri Nov 20 2020

...GALE WARNING THROUGH SATURDAY...

.TODAY...E wind 40 kt. Seas 13 ft.
.TONIGHT...SE wind 45 kt. Seas 13 ft.
.SAT...SE wind 35 kt becoming S 25 kt in the afternoon. Seas 11 ft.
.SAT NIGHT...S wind 20 kt. Seas 9 ft.
.SUN...SW wind 20 kt. Seas 8 ft.
.MON...SW wind 30 kt. Seas 9 ft.
.TUE...SE wind 30 kt. Seas 16 ft.

$$

PKZ185-210145-
Saint Matthew Island Waters-
341 AM AKST Fri Nov 20 2020

...GALE WARNING THROUGH SATURDAY...

.TODAY...E wind 35 kt E of Saint Matthew Island...N 30 kt W of
Saint Matthew Island. Seas 12 ft. Snow showers and rain showers.
.TONIGHT...E wind 40 kt E of Saint Matthew Island...N 30 kt W of
Saint Matthew Island. Seas 13 ft. Snow showers and rain showers.
.SAT...W wind 35 kt. Seas 13 ft.
.SAT NIGHT...SW wind 25 kt. Seas 13 ft.
.SUN...SW wind 25 kt. Seas 14 ft.
.MON...S wind 30 kt. Seas 20 ft.
.TUE...S wind 25 kt. Seas 20 ft.

$$

854 
FZAK52 PAFC 210038
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
338 PM AKST Fri Nov 20 2020

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.

PKZ199-211315-
338 PM AKST Fri Nov 20 2020
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 966 mb low at 58N 168W Fri afternoon moves into the northern
Bering by Sat afternoon. A 988 mb low at 49N 177W Sat afternoon
moves to 54N 158W at 982 mb by Sun afternoon. A new front
approaches the western Bering and Aleutians Sun afternoon.

$$

PKZ150-211315-
South of the AK Peninsula Sitkinak to Castle Cape-
338 PM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY NIGHT...

.TONIGHT...W wind 30 kt. Seas 15 ft.
.SAT...W wind 25 kt. Seas 14 ft.
.SAT NIGHT...SW wind 20 kt. Seas 11 ft.
.SUN...SE wind 30 kt. Seas 12 ft.
.SUN NIGHT...W wind 50 kt. Seas 19 ft.
.MON...NW wind 55 kt. Seas 26 ft.
.TUE...SW wind 35 kt. Seas 16 ft.
.WED...SW wind 30 kt. Seas 24 ft.

$$

PKZ155-211315-
South of the AK Peninsula Castle Cape to Cape Sarichef-
338 PM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY NIGHT...

.TONIGHT...W wind 30 kt. Seas 16 ft. Rain showers and snow
showers.
.SAT...W wind 25 kt. Seas 13 ft.
.SAT NIGHT...S wind 20 kt. Seas 9 ft.
.SUN...SE wind 25 kt. Seas 14 ft.
.SUN NIGHT...NW wind 50 kt. Seas 20 ft.
.MON...W wind 45 kt. Seas 20 ft.
.TUE...S wind 40 kt. Seas 22 ft.
.WED...SW wind 30 kt. Seas 28 ft.

$$

PKZ160-211315-
Bristol Bay-
338 PM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TONIGHT...S wind 25 kt. Seas 9 ft.
.SAT...W wind 25 kt. Seas 9 ft.
.SAT NIGHT...SW wind 20 kt. Seas 7 ft.
.SUN...E wind 25 kt. Seas 8 ft.
.SUN NIGHT...N wind 35 kt. Seas 8 ft.
.MON...NW wind 40 kt. Seas 12 ft.
.TUE...S wind 30 kt. Seas 8 ft.
.WED...SW wind 25 kt. Seas 8 ft.

$$

PKZ165-211315-
Port Heiden to Cape Sarichef-
338 PM AKST Fri Nov 20 2020

...GALE WARNING TONIGHT...

.TONIGHT...W wind 35 kt. Seas 20 ft. Rain showers and snow
showers.
.SAT...W wind 25 kt. Seas 16 ft. Rain showers and snow showers.
.SAT NIGHT...SW wind 20 kt. Seas 11 ft.
.SUN...NE wind 25 kt. Seas 8 ft.
.SUN NIGHT...NW wind 40 kt. Seas 13 ft.
.MON...W wind 35 kt. Seas 15 ft.
.TUE...S wind 35 kt. Seas 14 ft.
.WED...SW wind 30 kt. Seas 14 ft.

$$

PKZ170-211315-
Cape Sarichef to Nikolski Bering Side-
338 PM AKST Fri Nov 20 2020

...GALE WARNING TONIGHT...

.TONIGHT...W wind 35 kt. Seas 18 ft.
.SAT...W wind 25 kt. Seas 14 ft.
.SAT NIGHT...S wind 15 kt becoming E after midnight. Seas 10 ft.
.SUN...N wind 30 kt. Seas 10 ft.
.SUN NIGHT...NW wind 35 kt. Seas 14 ft.
.MON THROUGH TUE...S wind 40 kt. Seas 16 ft.
.WED...SW wind 30 kt. Seas 22 ft.

$$

PKZ171-211315-
Unalaska Bay-
338 PM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...W wind 30 kt diminishing to 20 kt after midnight. Seas
5 ft subsiding to 3 ft after midnight. Snow showers.
.SAT...W wind 15 kt becoming SW in the afternoon. Seas 2 ft.
.SAT NIGHT...S wind 10 kt becoming E after midnight. Seas 2 ft.
.SUN...N wind 30 kt. Seas 8 ft.
.SUN NIGHT...NW wind 30 kt. Seas 10 ft.
.MON...SW wind 30 kt. Seas 5 ft.
.TUE...S wind 25 kt. Seas 4 ft.
.WED...SW wind 20 kt. Seas 3 ft.

$$

PKZ172-211315-
Cape Sarichef to Nikolski Pacific Side-
338 PM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY NIGHT...

.TONIGHT...W wind 30 kt. Seas 15 ft. Rain showers.
.SAT...W wind 20 kt. Seas 11 ft.
.SAT NIGHT...S wind 20 kt becoming E after midnight. Seas 8 ft.
.SUN...N wind 35 kt. Seas 14 ft.
.SUN NIGHT...NW wind 40 kt. Seas 16 ft.
.MON...SW wind 35 kt. Seas 16 ft.
.TUE...SW wind 40 kt. Seas 23 ft.
.WED...SW wind 30 kt. Seas 25 ft.

$$

PKZ173-211315-
Nikolski to Seguam Island Bering Side-
338 PM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY NIGHT...

.TONIGHT...W wind 25 kt. Seas 14 ft.
.SAT...W wind 20 kt. Seas 10 ft.
.SAT NIGHT...SE wind 15 kt becoming NE after midnight. Seas 8 ft.
.SUN...NW wind 30 kt. Seas 11 ft.
.SUN NIGHT...W wind 30 kt. Seas 13 ft.
.MON THROUGH TUE...SW wind 40 kt. Seas 21 ft.
.WED...SW wind 30 kt. Seas 17 ft.

$$

PKZ174-211315-
Nikolski to Seguam Island Pacific Side-
338 PM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY NIGHT...

.TONIGHT...W wind 25 kt. Seas 15 ft.
.SAT...W wind 15 kt. Seas 11 ft.
.SAT NIGHT...NE wind 25 kt. Seas 10 ft.
.SUN...NW wind 35 kt. Seas 16 ft.
.SUN NIGHT...W wind 30 kt. Seas 15 ft.
.MON THROUGH TUE...SW wind 40 kt. Seas 23 ft.
.WED...SW wind 30 kt. Seas 19 ft.

$$

PKZ175-211315-
Seguam Island to Adak Bering Side-
338 PM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TONIGHT...W wind 20 kt. Seas 10 ft.
.SAT...W wind 15 kt. Seas 8 ft.
.SAT NIGHT...N wind 20 kt. Seas 6 ft.
.SUN...NW wind 30 kt. Seas 9 ft.
.SUN NIGHT...W wind 30 kt. Seas 11 ft.
.MON...S wind 50 kt. Seas 19 ft.
.TUE...SW wind 40 kt. Seas 16 ft.
.WED...SW wind 35 kt. Seas 13 ft.

$$

PKZ176-211315-
Seguam Island to Adak Pacific Side-
338 PM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY NIGHT...

.TONIGHT...W wind 20 kt. Seas 12 ft.
.SAT...W wind 15 kt becoming SE in the afternoon. Seas 10 ft.
.SAT NIGHT...N wind 25 kt. Seas 7 ft building to 11 ft after
midnight.
.SUN...NW wind 30 kt. Seas 13 ft.
.SUN NIGHT...W wind 30 kt. Seas 13 ft.
.MON...S wind 50 kt. Seas 26 ft.
.TUE...SW wind 40 kt. Seas 26 ft.
.WED...SW wind 30 kt. Seas 16 ft.

$$

PKZ177-211315-
Adak to Kiska-
338 PM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY NIGHT...

.TONIGHT...W wind 20 kt. Seas 11 ft.
.SAT...N wind 15 kt. Seas 8 ft.
.SAT NIGHT...N wind 20 kt. Seas 9 ft.
.SUN...W wind 30 kt. Seas 11 ft.
.SUN NIGHT...SW wind 35 kt. Seas 13 ft.
.MON...SW wind 50 kt. Seas 26 ft.
.TUE THROUGH WED...SW wind 35 kt. Seas 20 ft.

$$

PKZ178-211315-
Kiska to Attu-
338 PM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY TONIGHT AND SATURDAY NIGHT...

.TONIGHT...NW wind 15 kt. Seas 10 ft.
.SAT...NW wind 15 kt. Seas 7 ft.
.SAT NIGHT...NW wind 20 kt. Seas 8 ft.
.SUN...W wind 25 kt. Seas 10 ft.
.SUN NIGHT...SW wind 45 kt. Seas 20 ft.
.MON...SW wind 50 kt. Seas 26 ft.
.TUE THROUGH WED...SW wind 35 kt. Seas 21 ft.

$$

PKZ179-211315-
Pribilof Islands Near Shore Waters-
338 PM AKST Fri Nov 20 2020

...GALE WARNING THROUGH SATURDAY...

.TONIGHT...W wind 45 kt. Seas 18 ft.
.SAT...W wind 35 kt becoming SW 25 kt in the afternoon. 
Seas 15 ft.
.SAT NIGHT...SW wind 20 kt. Seas 12 ft.
.SUN...W wind 20 kt. Seas 8 ft.
.SUN NIGHT...W wind 30 kt. Seas 12 ft.
.MON THROUGH TUE...SW wind 40 kt. Seas 22 ft.
.WED...SW wind 30 kt. Seas 15 ft.

$$

PKZ180-211315-
Kuskokwim Delta and Etolin Strait-
338 PM AKST Fri Nov 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY NIGHT...

.TONIGHT...SE wind 30 kt. Seas 13 ft. Rain.
.SAT...SW wind 25 kt. Seas 13 ft.
.SAT NIGHT...SW wind 20 kt. Seas 10 ft.
.SUN...SE wind 20 kt. Seas 8 ft.
.SUN NIGHT...N wind 35 kt. Seas 7 ft.
.MON...W wind 30 kt. Seas 10 ft.
.TUE...S wind 30 kt. Seas 14 ft.
.WED...SW wind 25 kt. Seas 13 ft.

$$

PKZ181-211315-
North and West of Nunivak Island-
338 PM AKST Fri Nov 20 2020

...GALE WARNING THROUGH SATURDAY...

.TONIGHT...E wind 40 kt. Seas 13 ft.
.SAT...SE wind 40 kt becoming S 30 kt in the afternoon. 
Seas 11 ft.
.SAT NIGHT...S wind 20 kt. Seas 9 ft.
.SUN...S wind 15 kt. Seas 8 ft.
.SUN NIGHT...SW wind 20 kt. Seas 5 ft.
.MON...SW wind 30 kt. Seas 10 ft.
.TUE...SE wind 30 kt. Seas 16 ft.
.WED...S wind 25 kt. Seas 12 ft.

$$

PKZ185-211315-
Saint Matthew Island Waters-
338 PM AKST Fri Nov 20 2020

...GALE WARNING THROUGH SATURDAY...

.TONIGHT...E wind 35 kt E of Saint Matthew Island...N 25 kt W of
Saint Matthew Island. Seas 13 ft. Snow showers and rain showers.
.SAT...W wind 35 kt. Seas 13 ft.
.SAT NIGHT...E of Saint Matthew Island, SW wind 25 kt diminishing
to 15 kt after midnight. W of Saint Matthew Island, SW wind 30 kt. 
Seas 13 ft.
.SUN...SW wind 30 kt. Seas 9 ft.
.SUN NIGHT...SW wind 30 kt. Seas 14 ft.
.MON...S wind 45 kt. Seas 21 ft.
.TUE...S wind 30 kt. Seas 20 ft.
.WED...SW wind 20 kt. Seas 17 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
426 PM AKST Thu Nov 19 2020

.ANALYSIS AND UPPER LEVELS...
As discussed yesterday, a low developed south of Attu and has now
moved into the southern Bering Sea as a double-wrapped occlusion.
This low has an impressive amount of cold air aloft feeding into
it as evidenced by the cold-air cumulus clouds to the west and
south of it. The parent low has retrograded into eastern Russia,
but there is still a front that extends out of it over the Gulf of
Anadyr to Southwest Mainland Alaska and in the Gulf of Alaska.
This front is weakening as it moves into the ridge over the
interior of the state, but is still strong enough to bring some
light snowfall to the Kuskokwim Delta and Bristol Bay.

&&

.MODEL DISCUSSION...
Models are still struggling with the development and movement of
the lows, especially Friday night through Sunday. The large low in
the Bering Sea today is handled well until Friday night, but as
long as the NAM model is discarded after that time frame in the
Bering Sea region, there remains good enough model agreement for a
reasonable forecast solution. The biggest issue is in the western
Gulf of Alaska beginning Friday evening where a strong front is
moving into that area with the potential for low to develop along
this front. In this case, the GFS is being disregarded as it is
the only one that spins up a strong low off this front. The
remaining models have smaller lows develop along the front, but as
long as the focus remains on the front, and not the potential
individual lows, a forecast can be put together with reasonable
confidence.

The best news with the 12Z and 18Z model runs is that they are
converging on a solution for early next week. This would develop
a strong low south of the Alaska Peninsula and track it across
the southern Gulf of Alaska but not move it to the north Gulf
coast. This is slowly increasing confidence for the forecast for
early next week.

&&

.AVIATION...
PANC...VFR conditions and light winds will persist. The mid-level
clouds moving into the region should help keep fog out of the
airport through Friday.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3/Today
through Saturday night)...

The majority of the energy associated with an upper level trough
and surface cold front continue to dissipate this afternoon. Snow
has transitioned to rain on Kodiak Island, with a rain/snow mix
across Prince William Sound.

As we have been tracking, our next area of focus is with the next
upper level trough and surface front moving into the western
Bering. Formation of a triple point low along the left exit region
of the jet streak is possible, however, models greatly disagree
if a low center eventually forms at the surface, including where
and when. What models are capturing very well is the placement of
the surface front. Due to this, the forecast was created utilizing
this feature. Expect a significant area of gale force winds
entering the western Gulf tomorrow morning and propagating towards
the northern Gulf Coast Saturday morning. Expect storm force
winds across the Barren Islands Friday night and across the
northern Gulf Coast Saturday morning as a barrier jet sets up.

Precipitation will follow this front along the same timeframe with
a wintry mix anticipated for coastal regions and higher
elevations. Due to downsloping, the Anchorage Bowl looks to
largely remain dry with this system. Expect an increase in local
effect winds for the Turnagain Arm and Matanuska Valley, as the
pressure gradient tightens between high pressure over the mainland
and low pressure in the Gulf. These winds should be strongest
Saturday morning before diminishing Saturday night.

&&

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

Snow showers across interior Southwest Alaska will continue to
diminish overnight as remnants of a front weakens. The pattern
quickly shifts overnight into Friday morning as a low pressure
system moves into the eastern Bering. This frontal system will
bring strong winds and gusts to the Southwest coast and Alaska
Peninsula persisting through Friday evening. Expect widespread
snow to move over the coast starting tonight, spreading farther
inland throughout the day on Friday. Colder temperatures moving in
behind the front will allow for a chance of snow or mixed
precipitation along the Alaska Peninsula and Bristol Bay coastal
areas heading into the weekend.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...

A storm force low positioned between Dutch Harbor and the
Pribilofs this afternoon will keep an over the Bering and
Aleutians through the next few days. Winds will weaken to gale
force along the occluded front as it approaches the Southwest
coast overnight tonight into Friday. The strong winds will
continue throughout the day on Friday on the back side of this low
as cold air continues to be pulled into the region.

By Saturday morning, models over the eastern Bering and south of
the Alaska Peninsula continue to disagree on whether strong winds
will continue. Winds are forecasted to stay at small craft
advisory level or below in this package. However, winds could
increase if the outlying GFS solution wins out, which has an
intensifying closed low at the base of the trough over the
western Gulf on Saturday.

&&

.MARINE (Days 3 through 5: Sunday through Tuesday)...

Gulf of Alaska:

A lot of uncertainty remains during the 3-5 day timeframe. There
is moderate confidence a front associated with a strong low enters
the western Gulf Sunday afternoon. There is potential for storm
force winds over the Gulf waters beginning Sunday night and
lasting through Tuesday as the low tracks eastward into the Gulf.
There is still considerable uncertainty with the track and
strength of this low. Widespread gales are likely during this
time, however will need to continue to assess regarding the timing
and location of storm force winds.

Bering Sea:

Gale force winds are likely over the northern Bering waters
Sunday. There is potential for a storm force low to enter the
western Bering Sunday night. This low will spread gale force winds
across the central and eastern Bering through Tuesday. Model
solutions continue to struggle with strength and timing, however
there is high confidence in an active weather pattern over the
Bering through Tuesday.

&&

.LONG TERM FORECAST (Days 4 through 7...Monday through
Thursday)...

Beginning Monday, an upper level ridge over the central Bering is
flanked by two upper level lows - one over the Kamchatka
Peninsula and the other centered over the Gulf. As the Kamchatka
low moves eastward Monday into Tuesday, a more amplified pattern
will develop. Strong northwesterly flow is still possible over the
Alaska Peninsula late Monday into Tuesday as the pressure gradient
strengthens considerably. Meanwhile, ample cold air filling in on
the backside of the Kamchatka low will enhance winds across the
western Bering Tuesday. Model solutions (GFS/EC) suggest that a
second low develops over the central Aleutians late Tuesday into
Wednesday and lifts northward over the Bristol Bay area. As we
typically see with this type of pattern, there is potential for a
triple point low to form somewhere in the vicinity of Kodiak
Island late Wednesday. Depending on the track of this triple
point low, the middle of next week may present a more active
weather pattern across Southcentral.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Storm 131 132 150 413 414.
   Gales 120 125 132 138 139 155 160 165 170-175 179-181 185 351
352 412.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...EZ
SOUTHCENTRAL ALASKA...CK
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...AH
MARINE/LONG TERM...KO