Small Craft Advisory 892, NWS Anchorage, AK

897 
FZAK52 PAFC 220050
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
350 PM AKST Sat Nov 21 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.

PKZ199-221315-
350 PM AKST Sat Nov 21 2020
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 984 mb low Sun morning 250 nm southwest of Dutch Harbor moves 
to 100 nm south of Sand Point at 970 mb by Sun afternoon and then
moves into the Gulf by Mon morning. A front moves over the 
western Aleutians Sun afternoon and continues into the central 
Aleutians by Mon afternoon associated with a 964 mb low.

$$

PKZ150-221315-
South of the AK Peninsula Sitkinak to Castle Cape-
350 PM AKST Sat Nov 21 2020

...GALE WARNING SUNDAY AND SUNDAY NIGHT...

.TONIGHT...SW wind 20 kt. Seas 11 ft.
.SUN...SE wind 35 kt. Seas 13 ft. Rain.
.SUN NIGHT...SE wind 40 kt becoming NW after midnight. Seas 13 ft
building to 24 ft after midnight. Rain and snow.
.MON...NW wind 55 kt. Seas 31 ft.
.MON NIGHT...NW wind 50 kt. Seas 26 ft.
.TUE...S wind 40 kt. Seas 16 ft.
.WED...SW wind 30 kt. Seas 25 ft.
.THU...SW wind 25 kt. Seas 18 ft.

$$

PKZ155-221315-
South of the AK Peninsula Castle Cape to Cape Sarichef-
350 PM AKST Sat Nov 21 2020

...STORM WARNING SUNDAY NIGHT...

.TONIGHT...SE wind 20 kt. Seas 9 ft.
.SUN...E wind 25 kt. Seas 9 ft. Rain.
.SUN NIGHT...NW wind 40 kt increasing to 50 kt after midnight.
Seas 24 ft. Rain.
.MON...NW wind 50 kt. Seas 25 ft.
.MON NIGHT...W wind 40 kt. Seas 18 ft.
.TUE...S wind 45 kt. Seas 26 ft.
.WED...SW wind 35 kt. Seas 29 ft.
.THU...SW wind 25 kt. Seas 14 ft.

$$

PKZ160-221315-
Bristol Bay-
350 PM AKST Sat Nov 21 2020

...GALE WARNING SUNDAY NIGHT...

.TONIGHT...SW wind 20 kt. Seas 8 ft.
.SUN...SE wind 15 kt becoming E 25 kt in the afternoon. Seas 5 ft
building to 8 ft in the afternoon.
.SUN NIGHT...NE wind 35 kt. Seas 11 ft. Snow and rain.
.MON AND MON NIGHT...NW wind 40 kt. Seas 12 ft.
.TUE...SE wind 35 kt. Seas 10 ft.
.WED...S wind 30 kt. Seas 17 ft.
.THU...S wind 20 kt. Seas 12 ft.

$$

PKZ165-221315-
Port Heiden to Cape Sarichef-
350 PM AKST Sat Nov 21 2020

...GALE WARNING SUNDAY NIGHT...

.TONIGHT...SW wind 20 kt. Seas 11 ft.
.SUN...NE wind 25 kt. Seas 9 ft.
.SUN NIGHT...NW wind 40 kt. Seas 15 ft. Snow and rain.
.MON...NW wind 40 kt. Seas 16 ft.
.MON NIGHT...SW wind 40 kt. Seas 13 ft.
.TUE...S wind 45 kt. Seas 17 ft.
.WED...SW wind 35 kt. Seas 23 ft.
.THU...SW wind 25 kt. Seas 14 ft.

$$

PKZ170-221315-
Cape Sarichef to Nikolski Bering Side-
350 PM AKST Sat Nov 21 2020

...GALE WARNING SUNDAY NIGHT...

.TONIGHT...S wind 15 kt becoming E after midnight. Seas 9 ft.
.SUN...N wind 30 kt. Seas 11 ft. Rain.
.SUN NIGHT...W wind 35 kt. Seas 14 ft.
.MON...W wind 35 kt. Seas 14 ft.
.MON NIGHT...S wind 45 kt. Seas 19 ft.
.TUE...S wind 45 kt. Seas 21 ft.
.WED...SW wind 40 kt. Seas 20 ft.
.THU...SW wind 30 kt. Seas 14 ft.

$$

PKZ171-221315-
Unalaska Bay-
350 PM AKST Sat Nov 21 2020

...GALE WARNING SUNDAY NIGHT...

.TONIGHT...S wind 10 kt. Seas 2 ft.
.SUN...NE wind 15 kt becoming N 30 kt in the afternoon. Seas 7 ft.
Rain and snow.
.SUN NIGHT...NW wind 35 kt. Seas 12 ft.
.MON...W wind 30 kt. Seas 8 ft subsiding to 5 ft by afternoon.
.MON NIGHT...S wind 30 kt. Seas 5 ft.
.TUE...S wind 40 kt. Seas 5 ft.
.WED...SW wind 30 kt. Seas 5 ft.
.THU...S wind 20 kt. Seas 3 ft.

$$

PKZ172-221315-
Cape Sarichef to Nikolski Pacific Side-
350 PM AKST Sat Nov 21 2020

...GALE WARNING SUNDAY AND SUNDAY NIGHT...

.TONIGHT...E wind 20 kt. Seas 7 ft. Rain.
.SUN...NE wind 25 kt becoming NW 35 kt in the afternoon. Seas 8 ft
building to 14 ft in the afternoon. Rain with snow.
.SUN NIGHT...NW wind 40 kt. Seas 19 ft.
.MON...W wind 35 kt. Seas 18 ft.
.MON NIGHT...SW wind 40 kt. Seas 19 ft.
.TUE...S wind 45 kt. Seas 25 ft.
.WED...SW wind 35 kt. Seas 24 ft.
.THU...SW wind 30 kt. Seas 14 ft.

$$

PKZ173-221315-
Nikolski to Seguam Island Bering Side-
350 PM AKST Sat Nov 21 2020

...SMALL CRAFT ADVISORY SUNDAY AND SUNDAY NIGHT...

.TONIGHT...NE wind 20 kt. Seas 7 ft.
.SUN...NW wind 30 kt. Seas 10 ft.
.SUN NIGHT...NW wind 30 kt. Seas 13 ft.
.MON...SW wind 40 kt. Seas 16 ft.
.MON NIGHT...S wind 50 kt. Seas 25 ft.
.TUE...SW wind 50 kt. Seas 23 ft.
.WED THROUGH THU...S wind 30 kt. Seas 15 ft.

$$

PKZ174-221315-
Nikolski to Seguam Island Pacific Side-
350 PM AKST Sat Nov 21 2020

...GALE WARNING SUNDAY...

.TONIGHT...E wind 20 kt. Seas 8 ft. Rain.
.SUN...NW wind 35 kt. Seas 16 ft.
.SUN NIGHT...NW wind 30 kt. Seas 17 ft.
.MON...SW wind 40 kt. Seas 16 ft.
.MON NIGHT...S wind 50 kt. Seas 26 ft.
.TUE...SW wind 50 kt. Seas 27 ft.
.WED THROUGH THU...SW wind 30 kt. Seas 17 ft.

$$

PKZ175-221315-
Seguam Island to Adak Bering Side-
350 PM AKST Sat Nov 21 2020

...SMALL CRAFT ADVISORY SUNDAY AND SUNDAY NIGHT...

.TONIGHT...N wind 20 kt. Seas 6 ft.
.SUN...NW wind 25 kt. Seas 9 ft.
.SUN NIGHT...W wind 25 kt. Seas 11 ft.
.MON AND MON NIGHT...S wind 50 kt. Seas 21 ft.
.TUE...W wind 40 kt. Seas 17 ft.
.WED THROUGH THU...SW wind 30 kt. Seas 15 ft.

$$

PKZ176-221315-
Seguam Island to Adak Pacific Side-
350 PM AKST Sat Nov 21 2020

...SMALL CRAFT ADVISORY THROUGH SUNDAY NIGHT...

.TONIGHT...N wind 25 kt. Seas 9 ft.
.SUN...NW wind 30 kt. Seas 13 ft.
.SUN NIGHT...W wind 30 kt. Seas 14 ft.
.MON...SW wind 45 kt. Seas 21 ft.
.MON NIGHT...S wind 55 kt. Seas 30 ft.
.TUE...W wind 40 kt. Seas 27 ft.
.WED THROUGH THU...SW wind 30 kt. Seas 17 ft.

$$

PKZ177-221315-
Adak to Kiska-
350 PM AKST Sat Nov 21 2020

...GALE WARNING SUNDAY NIGHT...

.TONIGHT...N wind 20 kt. Seas 8 ft.
.SUN...W wind 30 kt. Seas 11 ft.
.SUN NIGHT...W wind 25 kt becoming SW 35 kt after midnight. Seas
14 ft.
.MON...S wind 55 kt. Seas 27 ft.
.MON NIGHT...SW wind 50 kt. Seas 27 ft.
.TUE THROUGH THU...SW wind 30 kt. Seas 20 ft.

$$

PKZ178-221315-
Kiska to Attu-
350 PM AKST Sat Nov 21 2020

...GALE WARNING SUNDAY NIGHT...

.TONIGHT...NW wind 20 kt. Seas 7 ft.
.SUN...W wind 25 kt. Seas 10 ft.
.SUN NIGHT...SW wind 35 kt becoming S 45 kt after midnight. Seas
14 ft building to 21 ft after midnight. Rain.
.MON...SW wind 50 kt. Seas 27 ft.
.MON NIGHT...W wind 35 kt. Seas 22 ft.
.TUE...SW wind 30 kt. Seas 19 ft.
.WED...SW wind 35 kt. Seas 21 ft.
.THU...SW wind 30 kt. Seas 18 ft.

$$

PKZ179-221315-
Pribilof Islands Near Shore Waters-
350 PM AKST Sat Nov 21 2020

...SMALL CRAFT ADVISORY TONIGHT AND SUNDAY NIGHT...

.TONIGHT...SW wind 20 kt. Seas 10 ft.
.SUN...W wind 15 kt. Seas 7 ft.
.SUN NIGHT...W wind 30 kt. Seas 11 ft.
.MON...SW wind 30 kt. Seas 13 ft.
.MON NIGHT...S wind 45 kt. Seas 26 ft.
.TUE...W wind 45 kt. Seas 26 ft.
.WED...SW wind 30 kt. Seas 14 ft.
.THU...SW wind 25 kt. Seas 12 ft.

$$

PKZ180-221315-
Kuskokwim Delta and Etolin Strait-
350 PM AKST Sat Nov 21 2020

...GALE WARNING SUNDAY NIGHT...

.TONIGHT...SW wind 20 kt. Seas 10 ft.
.SUN...E wind 20 kt. Seas 6 ft.
.SUN NIGHT...N wind 25 kt becoming NW 35 kt after midnight. Seas
8 ft.
.MON...NW wind 35 kt. Seas 10 ft.
.MON NIGHT...SW wind 35 kt. Seas 12 ft.
.TUE...SE wind 40 kt. Seas 17 ft.
.WED...SW wind 30 kt. Seas 17 ft.
.THU...SW wind 25 kt. Seas 13 ft.

$$

PKZ181-221315-
North and West of Nunivak Island-
350 PM AKST Sat Nov 21 2020

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...SW wind 20 kt. Seas 11 ft.
.SUN...SW wind 15 kt. Seas 7 ft.
.SUN NIGHT...Variable wind 10 kt becoming SW 20 kt after midnight.
Seas 5 ft.
.MON...W wind 25 kt. Seas 7 ft.
.MON NIGHT...S wind 40 kt. Seas 17 ft.
.TUE...SE wind 40 kt. Seas 20 ft.
.WED THROUGH THU...S wind 25 kt. Seas 11 ft.

$$

PKZ185-221315-
Saint Matthew Island Waters-
350 PM AKST Sat Nov 21 2020

...SMALL CRAFT ADVISORY THROUGH SUNDAY NIGHT...

.TONIGHT...SW wind 30 kt. Seas 12 ft.
.SUN...E of Saint Matthew Island, SW wind 15 kt. W of Saint
Matthew Island, SW wind 20 kt increasing to 30 kt in the afternoon. 
Seas 8 ft.
.SUN NIGHT...SW wind 25 kt E of Saint Matthew Island... SW 30 kt W
of Saint Matthew Island. Seas 13 ft.
.MON AND MON NIGHT...S wind 40 kt. Seas 19 ft.
.TUE...S wind 35 kt. Seas 24 ft.
.WED...SW wind 25 kt. Seas 17 ft.
.THU...SW wind 25 kt. Seas 11 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
459 PM AKST Fri Nov 20 2020

.ANALYSIS AND UPPER LEVELS...
A strong low is in the Bering Sea centered between the Pribilof
Islands and Nunivak Island this afternoon. The front with this low
stretches from the Kuskokwim Delta to Kodiak Island and then well
south of the Gulf of Alaska. Warm air is advecting along the
front from the southeast bringing above freezing temperatures
from southern Cook Inlet to the Bristol Bay and Kuskokwim Delta
areas. This is a rather thin area of warm air as the airmass ahead
of the front is cold and there is cold air behind the front. This
cold air behind the front can be see as cold-air cumulus clouds
across the western Bering Sea, the entirety of the Aleutian
Islands and ALaska Peninsula and southward to nearly 40N. The net
result of this is that while there is warm air, it will cut off
quickly as the front moves eastward and turn precipitation across
the area to all snow faster than other systems the keep a tap of
warm air due to persistent south-to-southeasterly flow.

&&

.MODEL DISCUSSION...

Models are doing better than yesterday, but there are still some
issues inputting much more uncertainty into the short-term periods
of the forecast than typical. The good part of the models is with
the strong low in the Bering Sea where that is being handled well.
The development of a low along the front in the Gulf is where the
questions remain. What has changed since yesterday is that models
basically now all indicate that a moderate-strength low will
develop southeast of Kodiak tonight and move to lower Cook Inlet
Saturday afternoon. 850 mb temperatures over the Gulf and north
Gulf coast are also a little bit warmer on the GFS than NAM and
this is an important detail as to whether precipitation along the
Gulf coast turns to mostly rain or remains snow. Models are trying
to cut off the warm air advection along the front by tomorrow so
that is perhaps the greatest uncertainty in the forecast.

&&

.AVIATION...
PANC...VFR conditions and northerly winds will persist. Low level
wind shear is expected to persist through the night and then
diminish tomorrow.

&&

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

The front across the Gulf of Alaska has brought rain to Kodiak
Island and the western Kenai Peninsula with a wintry mix of
precipitation for Prince William Sound, along with high winds and
waves across the Barren Islands.

Models have come into better agreement today that a triple point
low will form east of Kodiak Island tonight. The low is
anticipated to continue to strengthen, with storm force winds
across the Barren Islands and ample rainfall for Kodiak Island.
The front will continue towards the northern Gulf Coast Saturday,
with a storm force jet leading the way. This should begin to
weaken late Saturday morning into early Saturday afternoon.

Precipitation type is now a challenge with this low, as
temperatures look to hover right around -3 degrees Celsius at 850
mb. Due to this, a wintry mix of precipitation is expected across
coastal locations. Confidence is a bit higher today for
accumulating snowfall across the eastern Kenai Peninsula,
including Turnagain Pass, and western Prince William Sound tonight
into early Saturday. A Winter Weather Advisory for blowing snow has
been issued for Portage Valley through Turnagain Pass from this
afternoon until Saturday at 4 p.m. Expect visibilities of half
mile or less at times with wind gusts to 50 mph.

Strong downslope flow will keep the chances for precipitation
with this system out of the Anchorage Bowl until late Saturday.
The Turnagain Arm and Matanuska Valley winds will continue to
increase into the overnight hours before beginning to weaken
late Saturday. The surface low will continue up Cook Inlet on
Sunday, bringing better chances for snow to the Anchorage Bowl.

After this, another front enters the western Gulf on Sunday. This
will bring another increase to winds, waves and precipitation to
the Alaska Peninsula and Kodiak Island.

&&

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

A frontal system associated with a low in the Bering is currently
working its way through Southwest AK, dropping rain and snow as it
goes...depending on specific location. This front will exit the
region tomorrow. Quiet weather is expected for Sunday, save for
some showery precipitation. Sunday night into Monday a low moving
along the Eastern Aleutians will work its way into Southwest AK.
The track of this system will keep weather mainly around Bristol
Bay. Temperatures will be cold enough for precipitation to fall
as snow. Right now we have 2 to 4 inches of snow forecasted, with
highest amounts near Dillingham. Gusty northwesterly winds will be
present Monday behind the system, which may blow some snow
around. Although, temperatures right now are warm enough that the
chance for any appreciable blowing snow remains low. So, a little
bit of winter weather to start the week for Bristol Bay, with
quiet conditions elsewhere.

&&

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

A mature low pressure exists in the Eastern Bering. Its center is
just east of the Pribilofs and the frontal system has pushed
ashore into Southwest AK. Cold air and moisture wrapping around
the backside of the low is creating snow and windy conditions for
the Pribilofs. Gale force winds are also present in the Bering
with this system. This low will weaken and lift north out of our
forecast area by tomorrow afternoon. Cooler air will remain after
its exit.

Most of the Bering will be quiet until Monday. However, a low in
the North Pacific will scrape the Eastern Aleutians Sunday,
bringing rain and snow to locations there. Gusty northerly winds
will wrap in behind the low on Monday. Also on Monday, the next
frontal system enters the Western Bering. It will have storm force
winds as it enters, but will weaken as it progresses east.

&&

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

Gulf of Alaska:

Some uncertainty remains during the 3-5 day timeframe. There is
moderate confidence a front associated with a strong low near
Kodiak Island moves east across the southern Gulf on Monday.
Confidence is increasing that there will be a large area of Gales
with areas of storm force winds over the Gulf waters Monday
through Tuesday morning as the low tracks eastward into the Gulf.
There is still some uncertainty with the track and strength of
this low, however models are agreeing that it will take a track
across the southern Gulf. Fairly good confidence for decreasing
winds on Tuesday as high pressure moves across the Gulf before
another front enters the Gulf Wednesday with Gales possible.

Bering Sea:

Confidence is increasing that Gale to Storm force winds will
occur over the western and central Bering waters Monday as a
front moves across the Bering. Winds will decrease to Gales
Tuesday morning as the front slowly weakens. Late Tuesday into
Wednesday a low will develop south of the Aleutians and move into
the eastern Bering. However low confidence in track and strength
as models are all over the place, it is certain that an active
pattern will continue through Wednesday across the Bering.

&&

.LONG TERM FORECAST (Days 4 through 7...Tuesday through
Friday)...

The amplified pattern early in the week will transition to a more
zonal like pattern across the Bering and Gulf by Wednesday with a
series of shortwaves/fronts riding along the upper level jet near
the Aleutians and tracking into Southwest and Southcentral with
increasing chances of snow by mid- week.

Beginning Tuesday, an upper level low near the Bering Straits with
a front extending into the eastern Bering will move into the Gulf
on Wednesday as an upper level ridge moves east out of the Gulf.
Models also show a low forming along the front near the Aleutians
and tracking towards the eastern Bering and Southwest Alaska
Wednesday, however lots of uncertainty with track and strength of
this low. This front will then move into Southcentral Wednesday
into Thursday increasing chances of accumulating snow. However
there is uncertainty with timing and strength of this front.
Thursday into Friday additional lows and fronts may form near the
Aleutians and track into the Gulf, however models are all over the
place on track and strength of these features. It does look
certain that an active pattern will continue through Friday for
much of the forecast area.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Weather Advisory zone 125.
MARINE...Storms 119 120 130 131 139.
      Gales 125 132 136-138 140 165 170 179 181 185 352 412 414.
FIRE WEATHER...NONE.

&&

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