Gale Warning 837, NWS Anchorage, AK

544 
FZAK52 PAFC 311329 CCA
CWFALU

Coastal Waters Forecast...CORRECTED
National Weather Service Anchorage Alaska
429 AM AKST Thu Dec 31 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.

PKZ199-010215-
429 AM AKST Thu Dec 31 2020
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 925 mb low 100 nm south of Attu moves to 80 nm northeast of Attu 
this evening, then to 200 nm northeast of Attu at 940 mb by Fri 
evening.


$$

PKZ150-010215-
South of the AK Peninsula Sitkinak to Castle Cape-
429 AM AKST Thu Dec 31 2020

...GALE WARNING TONIGHT...

.TODAY...E wind 30 kt. Seas 14 ft building to 20 ft in the 
afternoon.
.TONIGHT...E wind 35 kt. Seas 18 ft.
.FRI...SE wind 30 kt. Seas 14 ft. Rain with snow.
.FRI NIGHT...NE wind 20 kt. Seas 12 ft.
.SAT THROUGH SUN...W wind 20 kt. Seas 15 ft.
.MON...NE wind 20 kt. Seas 17 ft.

$$

PKZ155-010215-
South of the AK Peninsula Castle Cape to Cape Sarichef-
429 AM AKST Thu Dec 31 2020

...GALE WARNING TONIGHT...

.TODAY...NE wind 30 kt. Seas 18 ft.
.TONIGHT...SE wind 40 kt. Seas 15 ft. Rain and snow.
.FRI...SW wind 20 kt, Seas 13 ft building to 18 ft in the
afternoon. From the Shumagin Islands E, S wind 30 kt becoming W 15 
kt in the afternoon, Seas 14 ft.
.FRI NIGHT...W wind 20 kt. Seas 19 ft.
.SAT...SW wind 20 kt. Seas 22 ft.
.SUN...W wind 25 kt. Seas 19 ft.
.MON...SE wind 15 kt. Seas 14 ft.

$$

PKZ160-010215-
Bristol Bay-
429 AM AKST Thu Dec 31 2020

...GALE WARNING TONIGHT AND FRIDAY...
...HEAVY FREEZING SPRAY WARNING FRIDAY...

.TODAY...E wind 25 kt. Seas 4 ft.
.TONIGHT...E wind 40 kt. Seas 11 ft. Freezing spray.
.FRI...E wind 40 kt diminishing to 30 kt in the afternoon. Seas
10 ft. Heavy freezing spray near coast. Rain and snow.
.FRI NIGHT...E wind 25 kt. Seas 5 ft.
.SAT THROUGH SUN...E wind 15 kt. Seas 5 ft.
.MON...NE wind 20 kt. Seas 5 ft.

$$

PKZ165-010215-
Port Heiden to Cape Sarichef-
429 AM AKST Thu Dec 31 2020

...GALE WARNING TONIGHT...

.TODAY...E wind 20 kt becoming SE 30 kt in the afternoon. Seas 7
ft.
.TONIGHT...SE wind 45 kt. Seas 12 ft. Rain.
.FRI...S wind 20 kt. Seas 13 ft. From Port Moller E, S wind 30 kt 
diminishing to 15 kt in the afternoon. Seas 10 ft.
.FRI NIGHT...S wind 20 kt. Seas 12 ft.
.SAT...S wind 20 kt. Seas 11 ft.
.SUN...SW wind 20 kt. Seas 11 ft.
.MON...SE wind 15 kt. Seas 9 ft.

$$

PKZ170-010215-
Cape Sarichef to Nikolski Bering Side-
429 AM AKST Thu Dec 31 2020

...STORM WARNING THROUGH TONIGHT...

.TODAY...SE wind 35 kt increasing to 55 kt in the afternoon. Seas
7 ft building to 16 ft in the afternoon. Rain and snow.
.TONIGHT...SE wind 50 kt becoming SW 30 kt after midnight. Seas
16 ft. Rain and snow.
.FRI...S wind 25 kt. Seas 18 ft.
.FRI NIGHT...S wind 25 kt. Seas 17 ft.
.SAT THROUGH SUN...SW wind 25 kt. Seas 16 ft.
.MON...NW wind 15 kt. Seas 10 ft.

$$

PKZ171-010215-
Unalaska Bay-
429 AM AKST Thu Dec 31 2020

...GALE WARNING THROUGH TONIGHT...

.TODAY...SE wind 25 kt increasing to 45 kt in the afternoon. Seas
4 ft building to 7 ft in the afternoon.
.TONIGHT...SE wind 45 kt becoming SW 25 kt after midnight. Seas 7
ft subsiding to 3 ft after midnight. Rain.
.FRI...S wind 15 kt. Seas 2 ft.
.FRI NIGHT...S wind 15 kt. Seas 2 ft.
.SAT THROUGH SUN...SW wind 15 kt. Seas 2 ft.
.MON...W wind 10 kt. Seas 3 ft.

$$

PKZ172-010215-
Cape Sarichef to Nikolski Pacific Side-
429 AM AKST Thu Dec 31 2020

...STORM WARNING TODAY...

.TODAY...SE wind 30 kt increasing to 50 kt in the afternoon. Seas
14 ft building to 22 ft in the afternoon. Rain and snow.
.TONIGHT...S wind 45 kt becoming SW 30 kt after midnight. Seas
19 ft. Rain and snow.
.FRI...SW wind 25 kt. Seas 26 ft. Rain and snow showers.
.FRI NIGHT...SW wind 30 kt. Seas 27 ft.
.SAT THROUGH SUN...SW wind 30 kt. Seas 26 ft.
.MON...W wind 20 kt. Seas 14 ft.

$$

PKZ173-010215-
Nikolski to Seguam Island Bering Side-
429 AM AKST Thu Dec 31 2020

...STORM WARNING TODAY...

.TODAY...SE wind 60 kt. Seas 19 ft building to 27 ft in the 
afternoon. Rain and snow.
.TONIGHT...SW wind 35 kt. Seas 19 ft. Rain and snow showers.
.FRI...SW wind 35 kt. Seas 20 ft. Snow showers.
.FRI NIGHT...SW wind 35 kt. Seas 20 ft.
.SAT THROUGH SUN...SW wind 30 kt. Seas 20 ft.
.MON...W wind 25 kt. Seas 10 ft.

$$

PKZ174-010215-
Nikolski to Seguam Island Pacific Side-
429 AM AKST Thu Dec 31 2020

...STORM WARNING TODAY...

.TODAY...SE wind 60 kt. Seas 26 ft. Snow and rain.
.TONIGHT...W wind 40 kt. Seas 24 ft building to 35 ft after 
midnight. Rain and snow showers.
.FRI...SW wind 35 kt. Seas 34 ft. Snow showers.
.FRI NIGHT...SW wind 40 kt. Seas 36 ft.
.SAT...SW wind 35 kt. Seas 35 ft.
.SUN...SW wind 35 kt. Seas 27 ft.
.MON...W wind 25 kt. Seas 19 ft.

$$

PKZ175-010215-
Seguam Island to Adak Bering Side-
429 AM AKST Thu Dec 31 2020

...HURRICANE FORCE WIND WARNING TODAY...

.TODAY...SE wind 65 kt becoming S 45 kt in the afternoon. Seas
24 ft. Rain and snow.
.TONIGHT...SW wind 45 kt. Seas 29 ft. Snow showers.
.FRI...SW wind 45 kt. Seas 26 ft. Widespread rain and snow showers. 
.FRI NIGHT...SW wind 40 kt. Seas 24 ft.
.SAT THROUGH SUN...SW wind 40 kt. Seas 22 ft.
.MON...NW wind 25 kt. Seas 9 ft.

$$

PKZ176-010215-
Seguam Island to Adak Pacific Side-
429 AM AKST Thu Dec 31 2020

...HURRICANE FORCE WIND WARNING TODAY...

.TODAY...SE wind 65 kt becoming SW 45 kt in the afternoon. Seas
30 ft. Rain and snow.
.TONIGHT...SW wind 45 kt. Seas 43 ft. Snow showers.
.FRI...SW wind 45 kt. Seas 41 ft. Widespread rain and snow showers. 
.FRI NIGHT...SW wind 45 kt. Seas 43 ft.
.SAT...SW wind 40 kt. Seas 38 ft.
.SUN...SW wind 35 kt. Seas 27 ft.
.MON...NW wind 25 kt. Seas 22 ft.

$$

PKZ177-010215-
Adak to Kiska-
429 AM AKST Thu Dec 31 2020

...HURRICANE FORCE WIND WARNING TODAY...

.TODAY...SW wind 65 kt. Bering side, seas 25 ft building to 45 ft in
the afternoon. Pacific side, seas 37 ft building to 55 ft in the 
afternoon. Rain and snow showers.
.TONIGHT...SW wind 60 kt. Seas 42 ft Bering side... 53 ft Pacific 
side. Widespread snow showers.
.FRI...SW wind 55 kt. Seas 33 ft Bering side... 48 ft Pacific side.
Widespread rain and snow showers.
.FRI NIGHT...SW wind 50 kt. Seas 46 ft.
.SAT...W wind 45 kt. Seas 34 ft.
.SUN...SW wind 35 kt. Seas 23 ft.
.MON...N wind 20 kt. Seas 18 ft.

$$

PKZ178-010215-
Kiska to Attu-
429 AM AKST Thu Dec 31 2020

...HURRICANE FORCE WIND WARNING THROUGH TONIGHT...

.TODAY...Bering side, SE wind 50 kt becoming SW 60 kt in the
afternoon, Seas 29 ft building to 48 ft in the afternoon. Pacific side,
S wind 70 kt, Seas 51 ft building to 60 ft in the afternoon. Rain 
and snow showers.
.TONIGHT...W wind 65 kt. Seas 45 ft Bering side...55 ft Pacific 
side. Widespread rain and snow showers.
.FRI...W wind 50 kt. Seas 33 ft Bering side...42 ft Pacific side.
Widespread rain and snow showers.
.FRI NIGHT...W wind 50 kt. Seas 35 ft.
.SAT...W wind 40 kt. Seas 26 ft.
.SUN THROUGH MON...N wind 35 kt. Seas 19 ft.

$$

PKZ179-010215-
Pribilof Islands Near Shore Waters-
429 AM AKST Thu Dec 31 2020

...STORM WARNING THROUGH TONIGHT...

.TODAY...SE wind 30 kt increasing to 50 kt in the afternoon. Seas
9 ft building to 15 ft in the afternoon. Rain and snow.
.TONIGHT...SE wind 50 kt becoming S 25 kt after midnight. Seas
21 ft subsiding to 16 ft after midnight. Rain and snow showers.
.FRI...S wind 25 kt. Seas 20 ft.
.FRI NIGHT...SE wind 30 kt. Seas 18 ft.
.SAT...SE wind 25 kt. Seas 18 ft.
.SUN...SE wind 25 kt. Seas 14 ft.
.MON...NE wind 25 kt. Seas 12 ft.

$$

PKZ180-010215-
Kuskokwim Delta and Etolin Strait-
429 AM AKST Thu Dec 31 2020

...GALE WARNING TONIGHT AND FRIDAY...
...HEAVY FREEZING SPRAY WARNING TONIGHT AND FRIDAY...

.TODAY...E wind 20 kt becoming SE 30 kt in the afternoon. Seas 7
ft.
.TONIGHT...E wind 45 kt. Seas 11 ft building to 16 ft after
midnight. Snow. Heavy freezing spray near coast.
.FRI...SE wind 45 kt diminishing to 30 kt in the afternoon. Seas
14 ft. Heavy freezing spray near coast.
.FRI NIGHT...SE wind 20 kt. Seas 9 ft.
.SAT...E wind 15 kt. Seas 8 ft.
.SUN THROUGH MON...NE wind 20 kt. Seas 7 ft.

$$

PKZ181-010215-
North and West of Nunivak Island-
429 AM AKST Thu Dec 31 2020

...GALE WARNING TONIGHT AND FRIDAY...
...HEAVY FREEZING SPRAY WARNING TONIGHT AND FRIDAY...

.TODAY...SE wind 20 kt becoming E 30 kt in the afternoon. Seas in
ice free waters 6 ft. Freezing spray.
.TONIGHT...E wind 45 kt. Seas in ice free waters 15 ft. Heavy 
freezing spray. Snow.
.FRI...E wind 45 kt becoming SE 35 kt in the afternoon. Seas in
ice free waters 14 ft subsiding to 9 ft in the afternoon. Heavy 
freezing spray.
.FRI NIGHT...E wind 20 kt. Seas in ice free waters 8 ft.
.SAT THROUGH SUN...NE wind 20 kt. Seas in ice free waters 6 ft.
.MON...NE wind 25 kt. Seas in ice free waters 4 ft.

$$

PKZ185-010215-
Saint Matthew Island Waters-
429 AM AKST Thu Dec 31 2020

...STORM WARNING THROUGH TONIGHT...

.TODAY...E of Saint Matthew Island, SE wind 25 kt becoming E 35 kt
in the afternoon. W of Saint Matthew Island, SE wind 30 kt
becoming E 50 kt in the afternoon. Seas 10 ft building to 16 ft in 
the afternoon.
.TONIGHT...E wind 45 kt E of Saint Matthew Island...E 55 kt W of
Saint Matthew Island. Seas 26 ft. Snow.
.FRI...E wind 45 kt becoming SE 30 kt in the afternoon. Seas 27
ft.
.FRI NIGHT...E wind 30 kt. Seas 21 ft.
.SAT THROUGH SUN...NE wind 35 kt. Seas 18 ft.
.MON...NE wind 30 kt. Seas 14 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
505 PM AKST Wed Dec 30 2020

.ANALYSIS AND UPPER LEVELS...

An upper trough centered over the Kenai Peninsula is producing
widespread cloud cover to the southern mainland, but with very
dry low levels for interior Southcentral, very little in the way
of precipitation is reaching the ground. Further south towards
Homer, there is enough moisture to support rain and snow showers,
but with minimal impact. A weak ridge of high pressure over the
Southwest coast allowed for the fog/stratus development from
Nunivak Island southward into Bristol Bay today, which reached
far enough inland today to bring periods of dense fog into King
Salmon. Over the Bering, the nearly stationary trough that has
been persistent over the western Bering is slowly moving to the
east and weakening in advance of a developing low approaching the
Western Aleutians. This low will continue strengthening into the
extremely deep, and potentially record breaking low as it moves
into the Western Aleutians late tonight.

&&

.MODEL DISCUSSION...

Model agreement in the main synoptic scale features is good into
Friday with both the approaching major Bering Sea storm and
placement of smaller scale features in the Gulf/Southcentral.
Agreement continues to improve with the intensity of the Bering
low, leading to improving confidence on the impacts of this
system through Friday. By late in the week, confidence begins to
waver both with the track of the Bering, and a much weaker low
through the Gulf. This is leading to lower confidence in the
Bering Sea and north Gulf Coast by the end of the work week.
Forecast confidence however is much higher for inland areas of the
southern Mainland.

&&

.AVIATION...

PANC...VFR conditions with light winds are expected to continue
into Thursday. There is an outside chance of a stray very light
snow shower this evening, but this is not expected to produce any
accumulation.

&&

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

A chance of an additional round of very light snow persists
across Anchorage Bowl, and over the eastern Kenai Peninsula and
Prince William Sound tonight. This is due to an upper low over the
Kenai Peninsula which is approaching the Anchorage Bowl this
evening. Both NAM and GFS differ slightly on the placement of the
upper low as it curves eastward to Prince William Sound, but the
potential for snow exists over the region as the upper level
pattern brings some energy combined with colder environmental
temperatures aloft to produce snowfall tonight. Once this upper
low phases out Thursday afternoon, drier conditions will move in
as general offshore flow sets in and local gap flows strengthen.
For now, will keep a close eye on the aforementioned low as it
could regain strength before retrograding westward.

&&

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

There is an area of troughing across Southwest Alaska which is
present at the surface and at 500 mb (middle atmosphere). This
will bring areas of light rain and snow to the Bristol Bay and
Kuskokwim Delta area. With time, the upper level trough will
become a closed low and push towards the Western Alaska Range
bringing a fresh blanket of snow to interior areas. A ferocious
low will move into the Bering with an estimated intensity of 922
mb - 925 mb. While the Bering will see the lions share of the
winds and precipitation, late Thursday and Friday winds will
increase as the front approaches western Alaska.

&&

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

There is a low with a magnitude of 947 mb southwest of Attu
Island this afternoon. This low will continue to deepen as it
heads towards the Western Aleutians tonight. This storm could end
up being a record-breaker. This low pressure system is expected
to bottom out Thursday morning around 922 to 925 mb based on
current model guidance. This will rival the Bering Sea storm from
1977 which had an observed pressure of 924 mb. The front
associated with this low will bring a band of storm and hurricane
force winds. The models actually bring 50 foot seas north and
south of the chain.

Winds will be near warning levels for Shemya with the initial
front Wednesday night and Thursday morning but should stay below
75 mph threshold so will not issue a high wind warning. Blowing
snow should be limited as temperatures warm above freezing fairly
quickly after the onset of snow Wednesday night and some locations
may even see temperatures near 40 degrees. On the latest
satellite imagery the moisture fetch associated with this system
extends to the northern Mariana Islands. This modified tropical
moisture will combine with strong cold air advection from Siberia
to help the low become so strong.

Thursday night and Friday the front will begin to weaken, but
the wind field is expansive and will still produce fairly strong
winds for the eastern Aleutians with gusts up to 50 knots and a
mix of rain and snow.

&&

.MARINE (Days 3 through 5: Saturday through Monday)...

Gulf of Alaska:
A barrier jet brings small craft winds over the northern Gulf
across Kodiak Island and the western Gulf through Sat. A broad
area of low pressure stretches across the Gulf through Mon. A
second low pressure center develops along the front over the southern
Gulf and sweeps into the eastern Gulf by Mon. Model track and
development are mixed but confidence is good for small craft winds
and waves with gale force gusts across the southern Gulf with
seas to 20 feet spreading northward over the Gulf through Mon.
Weak high pressure moves into the Western Gulf for Mon.

Aleutians/Bering:
A strong low tracks in a circle over the western Bering through
Mon. Model tracking and development are mixed but confidence
remains high for this wind wrapped low to spread high end gale
force winds and waves with storm force gusts over the Aleutians
and Bering mostly on Saturday, diminishing through Monday. This
brings seas to 45 feet on the Pacific side and 35 feet on the
Bering side between Shemya and Adak for Sat and diminishing slowly
through Mon. The low will continue with gale force winds and seas
to 20 feet over most of the Bering through Monday.

&&

.LONG TERM FORECAST (Days 4 through 7: Sunday through Wednesday)...

Confidence is fairly low in the specifics of the forecast this
weekend, but there is generally good confidence that any major
systems will remain offshore in the Bering and Gulf of Alaska into
early next week. As a result, the weather for much of the southern
mainland, especially interior areas, should remain fairly benign
and stable with temperatures near to slightly below normal.
Storminess will also continue to slowly diminish in the Bering
Sea/Aleutians into early next week.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...High Wind Warning: 187.
MARINE...Hurricane Force Wind Warning: 175-178 411 413.
Storm Warning: 170 172-174 179 185 412 414.
Gale Warning: 130 155-165 171 180 181 352.
Heavy Freezing Spray Warning: 180 181.

&&

SYNOPSIS AND MODEL DISCUSSION...DEK
SOUTHCENTRAL ALASKA...CMB
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...PJS
MARINE/LONG TERM...MF/DEK