Small Craft Advisory 362, NWS Anchorage, AK

668 
FZAK52 PAFC 041132
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
332 AM AKDT Tue May 4 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.

PKZ199-050100-
332 AM AKDT Tue May 4 2021
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 983 mb Kamchatka Low moves to 195 nm south of Kiska at 994 mb
for Wed afternoon. Its front moves from the western Bering to the
eastern Aleutians by Thu morning. A 992 mb low forms along the 
front 110 nm South of Atka Wed afternoon and moves to 80 nm north 
of Atka by Thu morning.

$$

PKZ150-050100-
South of the AK Peninsula Sitkinak to Castle Cape-
332 AM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY THROUGH TONIGHT...

.TODAY...N wind 30 kt. Seas 10 ft.
.TONIGHT...NE wind 30 kt. Seas 8 ft.
.WED...NE wind 20 kt. Seas 7 ft.
.WED NIGHT...E wind 15 kt. Seas 5 ft.
.THU THROUGH FRI...E wind 25 kt. Seas 8 ft.
.SAT...S wind 20 kt. Seas 10 ft.

$$

PKZ155-050100-
South of the AK Peninsula Castle Cape to Cape Sarichef-
332 AM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY TODAY...

.TODAY...NW wind 30 kt. Seas 9 ft.
.TONIGHT...NW wind 20 kt in the evening becoming variable 10 kt.
From the Shumagin Islands E, N wind 20 kt. Seas 6 ft.
.WED...E wind 20 kt. Seas 6 ft.
.WED NIGHT...E wind 30 kt. Seas 8 ft.
.THU...E wind 30 kt. Seas 9 ft.
.FRI...SW wind 25 kt. Seas 10 ft.
.SAT...S wind 25 kt. Seas 10 ft.

$$

PKZ160-050100-
Bristol Bay-
332 AM AKDT Tue May 4 2021

.TODAY...N wind 20 kt. Seas 4 ft.
.TONIGHT...S wind 15 kt. Seas 3 ft.
.WED...SE wind 15 kt becoming E in the afternoon. Seas 2 ft.
.WED NIGHT...NE wind 10 kt. Seas 2 ft.
.THU...E wind 15 kt. Seas 5 ft.
.FRI...E wind 20 kt. Seas 2 ft.
.SAT...SE wind 20 kt. Seas 2 ft.

$$

PKZ165-050100-
Port Heiden to Cape Sarichef-
332 AM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY WEDNESDAY...

.TODAY...NW wind 20 kt. Seas 6 ft.
.TONIGHT...NW wind 15 kt. Seas 4 ft.
.WED...SE wind 15 kt increasing to 25 kt in the afternoon. From
Port Moller E, E wind 15 kt. Seas 3 ft.
.WED NIGHT...E wind 30 kt. Seas 6 ft.
.THU...E wind 30 kt. Seas 7 ft.
.FRI...E wind 25 kt. Seas 6 ft.
.SAT...SE wind 20 kt. Seas 4 ft.

$$

PKZ170-050100-
Cape Sarichef to Nikolski Bering Side-
332 AM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY WEDNESDAY...

.TODAY...W wind 15 kt. Seas 7 ft.
.TONIGHT...SW wind 15 kt. Seas 4 ft.
.WED...SE wind 20 kt increasing to 30 kt in the afternoon. Seas
6 ft.
.WED NIGHT...E wind 40 kt gusting to 45 kt in bays and passes. Seas 
11 ft.
.THU...SE wind 35 kt. Seas 10 ft.
.FRI...SE wind 15 kt. Seas 7 ft.
.SAT...SE wind 20 kt. Seas 4 ft.

$$

PKZ171-050100-
Unalaska Bay-
332 AM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY WEDNESDAY...

.TODAY...W wind 15 kt diminishing to 10 kt in the afternoon. Seas
2 ft.
.TONIGHT...Variable wind less than 10 kt becoming SE 10 kt after
midnight. Seas 3 ft.
.WED...SE wind 25 kt. Seas 3 ft.
.WED NIGHT...SE wind 40 kt. Seas 5 ft.
.THU...SE wind 30 kt. Seas 4 ft.
.FRI...SE wind 10 kt. Seas 2 ft.
.SAT...SE wind 15 kt. Seas 2 ft.

$$

PKZ172-050100-
Cape Sarichef to Nikolski Pacific Side-
332 AM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY WEDNESDAY...

.TODAY...NW wind 20 kt. Seas 6 ft.
.TONIGHT...SW wind 15 kt. Seas 4 ft.
.WED...E wind 30 kt. Seas 8 ft.
.WED NIGHT...SE wind 35 kt. Seas 11 ft.
.THU...SE wind 30 kt. Seas 11 ft.
.FRI THROUGH SAT...SE wind 20 kt. Seas 9 ft.

$$

PKZ173-050100-
Nikolski to Seguam Island Bering Side-
332 AM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY THROUGH WEDNESDAY...

.TODAY...SW wind 15 kt becoming S 25 kt in the afternoon. Seas 7 ft.
.TONIGHT...SE wind 25 kt. Seas 5 ft.
.WED...E wind 30 kt. Seas 8 ft.
.WED NIGHT...SE wind 35 kt gusting to 45 kt in bays and passes. Seas
11 ft.
.THU THROUGH SAT...SE wind 20 kt. Seas 7 ft.

$$

PKZ174-050100-
Nikolski to Seguam Island Pacific Side-
332 AM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY THROUGH WEDNESDAY...

.TODAY...SW wind 15 kt becoming S 25 kt in the afternoon. Seas 7 ft.
.TONIGHT...SE wind 25 kt. Seas 7 ft.
.WED...E wind 30 kt. Seas 10 ft. Rain.
.WED NIGHT...S wind 30 kt. Seas 11 ft.
.THU THROUGH FRI...S wind 20 kt. Seas 11 ft.
.SAT...S wind 15 kt. Seas 8 ft.

$$

PKZ175-050100-
Seguam Island to Adak Bering Side-
332 AM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY TODAY...

.TODAY...SE wind 30 kt. Seas 7 ft. Rain and snow.
.TONIGHT...S wind 20 kt. Seas 6 ft.
.WED...SE wind 20 kt. Seas 6 ft. Rain.
.WED NIGHT...NE wind 25 kt. Seas 9 ft.
.THU...SE wind 15 kt. Seas 9 ft.
.FRI THROUGH SAT...S wind 15 kt. Seas 5 ft.

$$

PKZ176-050100-
Seguam Island to Adak Pacific Side-
332 AM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY THROUGH TONIGHT...

.TODAY...S wind 30 kt. Seas 10 ft. Rain.
.TONIGHT...S wind 20 kt in the evening becoming variable 10 kt.
Seas 8 ft.
.WED...SE wind 15 kt. Seas 7 ft.
.WED NIGHT...W wind 20 kt. Seas 9 ft.
.THU THROUGH SAT...S wind 20 kt. Seas 9 ft.

$$

PKZ177-050100-
Adak to Kiska-
332 AM AKDT Tue May 4 2021

...GALE WARNING TODAY...

.TODAY...S wind 35 kt becoming SW 20 kt in the afternoon. Seas
12 ft.
.TONIGHT...S wind 20 kt. Seas 8 ft.
.WED...SE wind 15 kt. Seas 8 ft.
.WED NIGHT...NE wind 20 kt. Seas 7 ft.
.THU...NW wind 25 kt. Seas 10 ft.
.FRI THROUGH SAT...W wind 20 kt. Seas 8 ft.

$$

PKZ178-050100-
Kiska to Attu-
332 AM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY THROUGH WEDNESDAY...

.TODAY...SW wind 25 kt. Seas 13 ft. Rain showers.
.TONIGHT...S wind 25 kt diminishing to 15 kt after midnight. Seas
12 ft.
.WED...SE wind 15 kt becoming NE in the afternoon. Seas 9 ft.
.WED NIGHT...N wind 20 kt. Seas 8 ft.
.THU...N wind 20 kt. Seas 10 ft.
.FRI...NW wind 25 kt. Seas 10 ft.
.SAT...NW wind 20 kt. Seas 8 ft.

$$

PKZ179-050100-
Pribilof Islands Near Shore Waters-
332 AM AKDT Tue May 4 2021

.TODAY...Variable wind 10 kt. Seas 4 ft.
.TONIGHT...Variable wind 10 kt. Seas 3 ft.
.WED...E wind 20 kt. Seas 5 ft.
.WED NIGHT...E wind 35 kt. Seas 10 ft.
.THU...E wind 30 kt. Seas 12 ft.
.FRI...E wind 20 kt. Seas 8 ft.
.SAT...SE wind 15 kt. Seas 4 ft.

$$

PKZ180-050100-
Kuskokwim Delta and Etolin Strait-
332 AM AKDT Tue May 4 2021

.TODAY...NW wind 20 kt. Seas in ice free waters 4 ft.
.TONIGHT...NW wind 15 kt becoming N after midnight. Seas in ice
free waters 3 ft.
.WED...SE wind 15 kt. Seas in ice free waters 2 ft.
.WED NIGHT...E wind 20 kt. Seas in ice free waters 3 ft.
.THU...E wind 20 kt. Seas in ice free waters 6 ft.
.FRI...NE wind 25 kt. Seas in ice free waters 5 ft.
.SAT...SE wind 20 kt. Seas in ice free waters 4 ft.

$$

PKZ181-050100-
North and West of Nunivak Island-
332 AM AKDT Tue May 4 2021

.TODAY...N wind 15 kt. Seas in ice free waters 2 ft. Freezing
spray.
.TONIGHT...N wind 15 kt. Seas in ice free waters 2 ft.
.WED...Variable wind 10 kt. Seas in ice free waters 2 ft.
.WED NIGHT...E wind 15 kt. Seas in ice free waters 3 ft.
.THU THROUGH FRI...NE wind 20 kt. Seas in ice free waters 5 ft.
.SAT...E wind 20 kt. Seas in ice free waters 3 ft.

$$

PKZ185-050100-
Saint Matthew Island Waters-
332 AM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY TONIGHT AND WEDNESDAY...

.TODAY...N wind 15 kt E of Saint Matthew Island...E 20 kt W of
Saint Matthew Island. Seas in ice free waters 3 ft.
.TONIGHT...Variable wind 10 kt E of Saint Matthew Island...E 25 kt
W of Saint Matthew Island. Seas in ice free waters 5 ft.
.WED...E wind 15 kt E of Saint Matthew Island...E 25 kt W of Saint
Matthew Island. Seas in ice free waters 7 ft.
.WED NIGHT...E wind 20 kt. Seas in ice free waters 7 ft.
.THU THROUGH FRI...NE wind 25 kt. Seas in ice free waters 9 ft.
.SAT...NE wind 25 kt. Seas in ice free waters 5 ft.

$$

142 
FZAK52 PAFC 042348
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
348 PM AKDT Tue May 4 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.

PKZ199-051315-
348 PM AKDT Tue May 4 2021
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 990 mb North Pacific low moves to 35 nm west of Adak at 984 mb 
for Thu afternoon.

$$

PKZ150-051315-
South of the AK Peninsula Sitkinak to Castle Cape-
348 PM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...NE wind 30 kt. Seas 10 ft.
.WED...NE wind 20 kt. Seas 7 ft.
.WED NIGHT...E wind 15 kt. Seas 5 ft.
.THU...SE wind 20 kt. Seas 6 ft.
.THU NIGHT...E wind 25 kt. Seas 10 ft.
.FRI...E wind 35 kt. Seas 13 ft.
.SAT...S wind 20 kt. Seas 10 ft.
.SUN...SE wind 25 kt. Seas 9 ft.

$$

PKZ155-051315-
South of the AK Peninsula Castle Cape to Cape Sarichef-
348 PM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY WEDNESDAY NIGHT...

.TONIGHT...NW wind 20 kt in the evening becoming variable 10 kt.
From the Shumagin Islands E, N wind 20 kt. Seas 6 ft.
.WED...E wind 20 kt. Seas 6 ft.
.WED NIGHT...E wind 30 kt except E 20 kt from the Shumagin Islands
E. Seas 9 ft.
.THU AND THU NIGHT...E wind 30 kt. Seas 10 ft.
.FRI...S wind 30 kt. Seas 10 ft.
.SAT THROUGH SUN...SE wind 25 kt. Seas 9 ft.

$$

PKZ160-051315-
Bristol Bay-
348 PM AKDT Tue May 4 2021

.TONIGHT...S wind 15 kt. Seas 4 ft.
.WED...SE wind 15 kt becoming E in the afternoon. Seas 4 ft.
.WED NIGHT...NE wind 10 kt. Seas 3 ft.
.THU...E wind 20 kt. Seas 5 ft.
.THU NIGHT...E wind 15 kt. Seas 4 ft.
.FRI THROUGH SAT...SE wind 20 kt. Seas 5 ft.
.SUN...E wind 25 kt. Seas 6 ft.

$$

PKZ165-051315-
Port Heiden to Cape Sarichef-
348 PM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY WEDNESDAY AND WEDNESDAY NIGHT...

.TONIGHT...NW wind 15 kt. Seas 4 ft.
.WED...SE wind 15 kt increasing to 25 kt in the afternoon. From
Port Moller E, E wind 15 kt. Seas 6 ft.
.WED NIGHT...SE wind 30 kt except E 25 kt from Port Moller E. Seas
9 ft.
.THU AND THU NIGHT...E wind 30 kt. Seas 9 ft.
.FRI...E wind 30 kt. Seas 9 ft.
.SAT THROUGH SUN...SE wind 20 kt. Seas 5 ft.

$$

PKZ170-051315-
Cape Sarichef to Nikolski Bering Side-
348 PM AKDT Tue May 4 2021

...GALE WARNING WEDNESDAY NIGHT...

.TONIGHT...SW wind 15 kt. Seas 4 ft.
.WED...SE wind 20 kt increasing to 30 kt in the afternoon. Seas
6 ft building to 9 ft in the afternoon.
.WED NIGHT...E wind 40 kt. Seas 11 ft.
.THU...SE wind 35 kt. Seas 11 ft.
.THU NIGHT...E wind 25 kt. Seas 7 ft.
.FRI...SE wind 15 kt. Seas 5 ft.
.SAT THROUGH SUN...S wind 20 kt. Seas 5 ft.

$$

PKZ171-051315-
Unalaska Bay-
348 PM AKDT Tue May 4 2021

...GALE WARNING WEDNESDAY NIGHT...

.TONIGHT...Variable wind less than 10 kt becoming SE 10 kt after
midnight. Seas 3 ft.
.WED...SE wind 25 kt. Seas 4 ft.
.WED NIGHT...SE wind 40 kt. Seas 5 ft. Rain.
.THU...SE wind 25 kt. Seas 4 ft.
.THU NIGHT...SE wind 10 kt. Seas 2 ft.
.FRI THROUGH SAT...SE wind 15 kt. Seas 2 ft.
.SUN...S wind 10 kt. Seas 2 ft.

$$

PKZ172-051315-
Cape Sarichef to Nikolski Pacific Side-
348 PM AKDT Tue May 4 2021

...GALE WARNING WEDNESDAY NIGHT...

.TONIGHT...SW wind 15 kt. Seas 5 ft.
.WED...E wind 30 kt. Seas 11 ft.
.WED NIGHT...E wind 35 kt. Seas 12 ft. Rain.
.THU...S wind 25 kt. Seas 10 ft.
.THU NIGHT...SE wind 15 kt. Seas 8 ft.
.FRI THROUGH SAT...SE wind 20 kt. Seas 9 ft.
.SUN...S wind 20 kt. Seas 7 ft.

$$

PKZ173-051315-
Nikolski to Seguam Island Bering Side-
348 PM AKDT Tue May 4 2021

...GALE WARNING WEDNESDAY NIGHT...

.TONIGHT...SE wind 25 kt. Seas 7 ft.
.WED...E wind 30 kt. Seas 10 ft.
.WED NIGHT...E wind 35 kt. Seas 12 ft. Rain.
.THU...SE wind 20 kt. Seas 9 ft.
.THU NIGHT...E wind 20 kt. Seas 7 ft.
.FRI THROUGH SAT...SE wind 20 kt. Seas 6 ft.
.SUN...S wind 15 kt. Seas 5 ft.

$$

PKZ174-051315-
Nikolski to Seguam Island Pacific Side-
348 PM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY THROUGH WEDNESDAY NIGHT...

.TONIGHT...SE wind 25 kt. Seas 7 ft.
.WED...E wind 30 kt. Seas 10 ft. Rain.
.WED NIGHT...S wind 30 kt diminishing to 20 kt after midnight.
Seas 11 ft.
.THU...S wind 20 kt. Seas 10 ft.
.THU NIGHT...SE wind 15 kt. Seas 9 ft.
.FRI...SE wind 20 kt. Seas 9 ft.
.SAT...S wind 15 kt. Seas 8 ft.
.SUN...S wind 20 kt. Seas 7 ft.

$$

PKZ175-051315-
Seguam Island to Adak Bering Side-
348 PM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY WEDNESDAY NIGHT...

.TONIGHT...S wind 20 kt. Seas 6 ft.
.WED...SE wind 20 kt. Seas 6 ft. Rain.
.WED NIGHT...NE wind 25 kt. Seas 9 ft. Rain.
.THU...S wind 20 kt. Seas 9 ft.
.THU NIGHT...E wind 20 kt. Seas 8 ft.
.FRI...NE wind 15 kt. Seas 6 ft.
.SAT...S wind 15 kt. Seas 5 ft.
.SUN...Variable wind 10 kt. Seas 4 ft.

$$

PKZ176-051315-
Seguam Island to Adak Pacific Side-
348 PM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY TONIGHT AND WEDNESDAY NIGHT...

.TONIGHT...S wind 20 kt in the evening becoming variable 10 kt.
Seas 8 ft.
.WED...SE wind 15 kt. Seas 7 ft.
.WED NIGHT...SW wind 20 kt. Seas 9 ft.
.THU...SW wind 20 kt. Seas 9 ft.
.THU NIGHT...E wind 15 kt. Seas 9 ft.
.FRI...N wind 20 kt. Seas 9 ft.
.SAT THROUGH SUN...SW wind 20 kt. Seas 7 ft.

$$

PKZ177-051315-
Adak to Kiska-
348 PM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY THROUGH WEDNESDAY...

.TONIGHT...S wind 20 kt. Seas 8 ft.
.WED...SE wind 15 kt. Seas 8 ft.
.WED NIGHT...N wind 20 kt. Seas 7 ft.
.THU...NW wind 25 kt. Seas 11 ft.
.THU NIGHT...N wind 30 kt. Seas 12 ft.
.FRI...NW wind 20 kt. Seas 8 ft.
.SAT...W wind 20 kt. Seas 6 ft.
.SUN...SW wind 15 kt. Seas 6 ft.

$$

PKZ178-051315-
Kiska to Attu-
348 PM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY THROUGH WEDNESDAY NIGHT...

.TONIGHT...S wind 25 kt diminishing to 15 kt after midnight. Seas
12 ft.
.WED...SE wind 15 kt becoming NE in the afternoon. Seas 9 ft.
.WED NIGHT...N wind 20 kt. Seas 8 ft.
.THU...N wind 20 kt. Seas 8 ft.
.THU NIGHT...N wind 25 kt. Seas 10 ft.
.FRI...N wind 25 kt. Seas 10 ft.
.SAT...NW wind 20 kt. Seas 8 ft.
.SUN...NW wind 15 kt. Seas 7 ft.

$$

PKZ179-051315-
Pribilof Islands Near Shore Waters-
348 PM AKDT Tue May 4 2021

...GALE WARNING WEDNESDAY NIGHT...

.TONIGHT...Variable wind 10 kt. Seas 3 ft.
.WED...E wind 20 kt. Seas 6 ft.
.WED NIGHT...E wind 25 kt increasing to 35 kt after midnight. Seas
10 ft.
.THU...E wind 35 kt. Seas 13 ft.
.THU NIGHT...E wind 30 kt. Seas 12 ft.
.FRI...E wind 25 kt. Seas 8 ft.
.SAT THROUGH SUN...E wind 15 kt. Seas 4 ft.

$$

PKZ180-051315-
Kuskokwim Delta and Etolin Strait-
348 PM AKDT Tue May 4 2021

.TONIGHT...NW wind 15 kt becoming NE after midnight. Seas in ice
free waters 3 ft.
.WED...SE wind 15 kt. Seas in ice free waters 3 ft.
.WED NIGHT...E wind 20 kt. Seas in ice free waters 4 ft.
.THU...E wind 25 kt. Seas in ice free waters 6 ft.
.THU NIGHT...E wind 20 kt. Seas in ice free waters 5 ft.
.FRI...E wind 25 kt. Seas in ice free waters 6 ft.
.SAT THROUGH SUN...E wind 20 kt. Seas in ice free waters 4 ft.

$$

PKZ181-051315-
North and West of Nunivak Island-
348 PM AKDT Tue May 4 2021

.TONIGHT...N wind 15 kt. Seas in ice free waters 2 ft.
.WED...Variable wind 10 kt. Seas in ice free waters 2 ft.
.WED NIGHT...E wind 15 kt. Seas in ice free waters 3 ft.
.THU...E wind 25 kt. Seas in ice free waters 5 ft.
.THU NIGHT...NE wind 20 kt. Seas in ice free waters 5 ft.
.FRI...NE wind 20 kt. Seas in ice free waters 4 ft.
.SAT THROUGH SUN...E wind 20 kt. Seas in ice free waters 3 ft.

$$

PKZ185-051315-
Saint Matthew Island Waters-
348 PM AKDT Tue May 4 2021

...SMALL CRAFT ADVISORY THROUGH WEDNESDAY NIGHT...

.TONIGHT...Variable wind 10 kt E of Saint Matthew Island...E 25 kt
W of Saint Matthew Island. Seas in ice free waters 5 ft.
.WED...E wind 15 kt E of Saint Matthew Island...E 25 kt W of Saint
Matthew Island. Seas in ice free waters 7 ft.
.WED NIGHT...E wind 20 kt E of Saint Matthew Island... E 25 kt W
of Saint Matthew Island. Seas in ice free waters 7 ft.
.THU AND THU NIGHT...NE wind 25 kt. Seas in ice free waters 9 ft.
.FRI THROUGH SAT...NE wind 25 kt. Seas in ice free waters 7 ft.
.SUN...NE wind 20 kt. Seas in ice free waters 4 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
450 AM AKDT Mon May 3 2021

.ANALYSIS AND UPPER LEVELS...

The upper-level longwave pattern is dominated by a trough
extending from the Gulf of Alaska west to the central Bering and
Aleutians. Downstream, an upper-level ridge is positioned from the
Canadian Rockies north and west to the Al-Can border. Embedded
within the longwave trough are a duo of upper-level lows, the
first of which is centered over the southern Gulf. The second
is currently over the Pribilofs and continues to move southeast
toward the eastern Aleutians.

The upper-level pattern lends to a complex synoptic set up at the
surface. The first upper-level low is vertically stacked and is
associated with a 996 mb low over the southern Gulf. This feature
is extending a front northward. Broad easterly flow ahead of and
along the front is pushing moisture across the northern Gulf, with
rain falling over Kodiak Island. Showers are also present around
Prince William Sound this morning, the result of a weaker
shortwave lifting north and west ahead of the main upper-level
low.

Mixed rain and snow is also falling this morning along a frontal
boundary extending from the AKPEN north over the eastern Bering.
This boundary is separating a more seasonal airmass with 850mb
temperatures around -5C from a wintry airmass over the central
Bering with 850 mb temperatures dropping to -12C. Thus,
precipitation falling east of this front is falling as rain. West
of the front, brisk northwesterly winds and snow showers are
occurring from Saint Paul and Unalaska to Cold Bay. A surface low
along the front south of Saint Paul is strengthening this morning
as the upper-level low drops south. This is helping to enhance the
winds and show shower activity across the western AKPEN.

A third surface low over the central Bering is also beginning its
trek southward this morning. This feature has good upper-level
support, aided by the 500 mb low moving south and a north-south
oriented 140 kt jet streak currently over the central Aleutians.

&&

.MODEL DISCUSSION...

Models remain in good synoptic agreement leading to above average
forecast confidence through the short term. The challenges again
are with local effects such as the strength of the Turnagain Arm
wind and the Knik Valley wind as diurnal heating across the
interior battles with increasing cloud cover and a developing
down inlet flow given the synoptic pattern. There is also good
agreement on the development of snow showers and gusty
northwesterly winds over the eastern Aleutians this morning.
However, there is still some uncertainty as to the intensity of
the shower activity, especially given that the intensity of
yesterday's snow shower activity over the western AKPEN out
performed model solutions.

&&

.AVIATION...
PANC...VFR conditions will persist. The Turnagain Arm wind is
expected to bend back over the terminal by late afternoon or early
evening. Gusts are not expected to be overly strong, peaking
around 20kts. The winds should relax again after midnight.

&&

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

A low will weaken over the central Gulf today, remaining just out
of reach of a trough south of the Alaska Peninsula lifting
northward toward Kodiak and the southwestern Gulf of Alaska.
Previous forecasts were based on the idea that this low would be
pulled westward toward Kodiak Island as the upper trough
approached. As a result, rainfall on Kodiak Island will initially
be quite light. However, expect a new surface low to form near
Kodiak Island in response to the upper level short-wave and
rainfall rates will increase this afternoon and persist through
tonight. The airmass accompanying the trough is quite cold for
May, with 1000-850 thicknesses as low as 1285 to 1290 meters. As
this airmass reaches Kodiak Island late tonight through Tuesday
morning, expect some snow in the mountains and perhaps even a mix
of rain and snow down to sea level. Surface temperatures at sea
level will remain above freezing, so do not expect any snow
accumulation. The low will exit southward on Tuesday, with
precipitation tapering off through the day.

For Southcentral, the remnants of the trough currently over the
Gulf along with a weak surface front will push onshore along the
north Gulf coast tonight through Tuesday, bringing areas of rain
(and mountain snow) to the eastern Kenai Peninsula and Prince
William Sound areas. Some of this moisture will spread inland in
the form of showers on Tuesday, aided by cold air advection aloft
and the resultant increased instability. While precipitation will
not be widespread, it is looking more favorable for showers to
track across Anchorage and the Mat-Su.

The entire region will dry out Tuesday night through Wednesday and
remain dry through Thursday. Very weak cyclonic flow aloft will
persist, so some clouds will likely remain in the region. Still,
would expect at least some breaks of sun each day along with a
gradual warm-up in temperatures.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1-2: Monday morning
through Wednesday morning)...

A low over the central Bering continues to move southward. This
will keep warm north to northeasterly flow in place across
Southwest today. A rain/snow mix over the Alaska Peninsula this
morning will eventually change to all rain as warm air works back
in. As the low tracks toward the southeast and moves into the
western Gulf, cloud cover will gradually increase across the area
from east to west on Tuesday. Cold air wrapping back in around the
low will keep showery conditions in place across the Lower
Kuskokwim Valley and interior Bristol Bay region through early
Wednesday.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1-2: Monday
morning through Wednesday morning)...

A low centered over the Pribilofs is moving southward toward the
central Aleutians, spreading abundant cold air across the central
Bering. Gusty northwesterly winds will continue for the central
Bering today with an intense shot of widespread snow showers along
the central and eastern Aleutians. As the low continues to move
southward, precipitation will taper by this afternoon. Farther
west, a gale force front arrives over the western Aleutians
bringing gusty southerly winds and rain. The front will gradually
weaken as it reaches the central Bering by Tuesday afternoon.
Broad low pressure begins to move in across the Bering for
Wednesday morning.

&&

.MARINE (Days 3 through 5: Wednesday through Friday)...

Bering: A North Pacific low moves along the Aleutians through
Friday. Its front pushes ahead of the low over the Bering into
Southwest Alaska by Friday. West of the low, high end small craft
winds with areas of gale force winds diminish over the Bering
Thursday. Small craft winds ahead of the front expected with areas
of gale force winds developing near channeled terrain over the
Eastern Aleutians and Alaska Peninsula, diminish Friday.

Gulf of Alaska: Expect winds less than 35 kts and seas less than
20 ft for the Day 3 through 5 period.

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

A low centered over the western Aleutians and its associated front
will bring rain generally west of Cold Bay on Thursday. With
relatively higher pressure to the east, gusty southeasterly winds
are also likely over Unalaska. Model agreement is poor on exactly
where the low will track thereafter and how broad the overall
circulation will be. In any case precipitation looks to continue
over the central/eastern Aleutians into the weekend with drier,
northerly flow behind it.

Farther east, quiet conditions are expected on Thursday with only
some light showers possible near higher terrain in the afternoon.
A front will move into the Gulf on Friday, potentially bringing
steady rain to Kodiak and extending westward into the Bristol Bay
area. The rest of the Mainland looks to remain dry. The front will
merge with a weakening low in the eastern Gulf Friday night and
continue to track northward. Model agreement is poor through the
weekend, but the pattern would indicate precipitation along the
coast and near higher terrain, with Anchorage and the Matanuska
Valley remaining mostly dry in downsloped easterly flow.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Flood Advisory 145.
MARINE...Gale Warning 132 150 170 172-174 177 178 352 411-413.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...TM
SOUTHCENTRAL ALASKA...SEB
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...KO
MARINE/LONG TERM...MK/AP

SPECIAL WEATHER STATEMENT
National Weather Service ANCHORAGE AK
1258 PM AKDT Mon May 3 2021

AKZ185-040300-
Eastern Aleutians-
Including the cities of Unalaska and Nikolski
1258 PM AKDT Mon May 3 2021

...GUSTY WINDS AND SNOW SHOWERS EXPECTED FOR THE EASTERN
ALEUTIANS TONIGHT THROUGH THIS EVENING...

A low over the central Bering will continue to move south bringing
short- lived, but intense snow showers to the eastern Aleutians.
In addition, gusty northwesterly winds will create blowing snow
conditions, which may limit visibility to one mile at times.

As the low continues to move southward, conditions will improve
across the eastern Aleutians by this evening.