Small Craft Advisory 1016, NWS Anchorage, AK

345 
FZAK52 PAFC 192346
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
246 PM AKST Sun Dec 19 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.

PKZ199-201245-
246 PM AKST Sun Dec 19 2021
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 988mb low 190 nm north of Attu moves to 100 nm west of Nunivak
Island at 1015mb Mon afternoon and weakens as it moves onshore 
Mon night. Its front moves across the Bering through Mon morning. 
A North Pacific low moves to 270 nm south of Shemya at 975mb 
Tuesday morning and then 150 nm west of Attu at 970mb Tuesday 
afternoon. Its front moves across the Aleutians and southern 
Bering Mon night through Tuesday afternoon.

$$

PKZ150-201245-
South of the AK Peninsula Sitkinak to Castle Cape-
246 PM AKST Sun Dec 19 2021

...SMALL CRAFT ADVISORY THROUGH MONDAY NIGHT...

.TONIGHT...W wind 25 kt. Seas 10 ft.
.MON...SW wind 25 kt. Seas 10 ft.
.MON NIGHT...NW wind 25 kt. Seas 11 ft.
.TUE...NW wind 30 kt. Seas 11 ft.
.TUE NIGHT...NW wind 20 kt. Seas 8 ft.
.WED THROUGH THU...W wind 25 kt. Seas 9 ft.
.FRI...W wind 20 kt. Seas 9 ft.

$$

PKZ155-201245-
South of the AK Peninsula Castle Cape to Cape Sarichef-
246 PM AKST Sun Dec 19 2021

...SMALL CRAFT ADVISORY THROUGH MONDAY NIGHT...

.TONIGHT...SW wind 30 kt. Seas 13 ft. Rain.
.MON...SW wind 25 kt. Seas 13 ft.
.MON NIGHT AND TUE...NW wind 15 kt. Seas 12 ft.
.TUE NIGHT...SW wind 20 kt. Seas 7 ft.
.WED...SW wind 25 kt. Seas 10 ft.
.THU THROUGH FRI...SW wind 20 kt. Seas 10 ft.

$$

PKZ160-201245-
Bristol Bay-
246 PM AKST Sun Dec 19 2021

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...S wind 25 kt. Seas in ice free waters 4 ft. Rain.
.MON...SW wind 20 kt. Seas in ice free waters 4 ft.
.MON NIGHT...W wind 20 kt. Seas in ice free waters 3 ft.
.TUE...NW wind 15 kt. Seas in ice free waters 3 ft.
.TUE NIGHT...Variable wind 10 kt. Seas in ice free waters 2 ft.
.WED...SW wind 25 kt. Seas in ice free waters 3 ft.
.THU...W wind 20 kt. Seas in ice free waters 3 ft.
.FRI...S wind 10 kt. Seas in ice free waters 2 ft.

$$

PKZ165-201245-
Port Heiden to Cape Sarichef-
246 PM AKST Sun Dec 19 2021

...SMALL CRAFT ADVISORY THROUGH MONDAY...

.TONIGHT...S wind 30 kt. Seas 13 ft. Rain.
.MON...SW wind 20 kt. Seas 10 ft.
.MON NIGHT...NW wind 20 kt. Seas 7 ft.
.TUE...N wind 15 kt. Seas 7 ft.
.TUE NIGHT...SE wind 25 kt. Seas 5 ft.
.WED...SW wind 25 kt. Seas 7 ft.
.THU THROUGH FRI...S wind 20 kt. Seas 6 ft.

$$

PKZ170-201245-
Cape Sarichef to Nikolski Bering Side-
246 PM AKST Sun Dec 19 2021

...SMALL CRAFT ADVISORY THROUGH MONDAY NIGHT...

.TONIGHT...S wind 30 kt. Seas 14 ft. Rain.
.MON...NW wind 15 kt. Seas 8 ft.
.MON NIGHT...NE wind 20 kt. Seas 8 ft.
.TUE...SE wind 25 kt. Seas 7 ft.
.TUE NIGHT...S wind 30 kt. Seas 9 ft.
.WED...SW wind 30 kt. Seas 9 ft.
.THU THROUGH FRI...S wind 25 kt. Seas 9 ft.

$$

PKZ171-201245-
Unalaska Bay-
246 PM AKST Sun Dec 19 2021

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...S wind 25 kt. Seas 4 ft
 subsiding to 2 ft after midnight. Rain.
.MON...NW wind 10 kt. Seas 3 ft. Rain.
.MON NIGHT...N wind 10 kt. Seas 3 ft.
.TUE...SE wind 20 kt. Seas 3 ft.
.TUE NIGHT...S wind 20 kt. Seas 2 ft.
.WED...SW wind 20 kt. Seas 2 ft.
.THU...S wind 15 kt. Seas 2 ft.
.FRI...S wind 20 kt. Seas 3 ft.

$$

PKZ172-201245-
Cape Sarichef to Nikolski Pacific Side-
246 PM AKST Sun Dec 19 2021

...SMALL CRAFT ADVISORY THROUGH MONDAY NIGHT...

.TONIGHT...S wind 30 kt. Seas 17 ft. Rain.
.MON...SW wind 25 kt. Seas 16 ft.
.MON NIGHT...N wind 20 kt. Seas 12 ft.
.TUE...SE wind 25 kt. Seas 10 ft.
.TUE NIGHT THROUGH FRI...S wind 25 kt. Seas 12 ft.

$$

PKZ173-201245-
Nikolski to Seguam Island Bering Side-
246 PM AKST Sun Dec 19 2021

...SMALL CRAFT ADVISORY THROUGH MONDAY NIGHT...

.TONIGHT...SW wind 30 kt becoming NW 15 kt after midnight.
Seas 14 ft. Rain.
.MON...NW wind 15 kt. Seas 10 ft.
.MON NIGHT...E wind 20 kt increasing to 30 kt after midnight.
Seas 9 ft.
.TUE...SE wind 35 kt. Seas 13 ft.
.TUE NIGHT...S wind 30 kt. Seas 14 ft.
.WED THROUGH FRI...S wind 25 kt. Seas 13 ft.

$$

PKZ174-201245-
Nikolski to Seguam Island Pacific Side-
246 PM AKST Sun Dec 19 2021

...SMALL CRAFT ADVISORY THROUGH MONDAY NIGHT...

.TONIGHT...S wind 30 kt. Seas 18 ft. Rain.
.MON...N wind 20 kt. Seas 16 ft. Rain.
.MON NIGHT...E wind 30 kt. Seas 14 ft. Rain.
.TUE AND TUE NIGHT...S wind 30 kt. Seas 16 ft.
.WED...S wind 25 kt. Seas 16 ft.
.THU...SE wind 30 kt. Seas 13 ft.
.FRI...SE wind 30 kt. Seas 18 ft.

$$

PKZ175-201245-
Seguam Island to Adak Bering Side-
246 PM AKST Sun Dec 19 2021

...GALE WARNING MONDAY NIGHT...

.TONIGHT...W wind 20 kt. Seas 9 ft.
.MON...NW wind 15 kt becoming E in the afternoon. Seas 9 ft.
.MON NIGHT...E wind 25 kt increasing to 40 kt after midnight.
Seas 7 ft building to 12 ft after midnight. Rain.
.TUE...SE wind 40 kt. Seas 14 ft.
.TUE NIGHT...S wind 35 kt. Seas 12 ft.
.WED...S wind 30 kt. Seas 10 ft.
.THU...SE wind 25 kt. Seas 8 ft.
.FRI...SE wind 20 kt. Seas 10 ft.

$$

PKZ176-201245-
Seguam Island to Adak Pacific Side-
246 PM AKST Sun Dec 19 2021

...GALE WARNING MONDAY NIGHT...

.TONIGHT...W wind 20 kt. Seas 18 ft.
.MON...N wind 15 kt becoming NE 25 kt in the afternoon. Seas 15
ft.
.MON NIGHT...E wind 40 kt. Seas 17 ft. Rain.
.TUE...SE wind 40 kt. Seas 22 ft.
.TUE NIGHT...S wind 35 kt. Seas 22 ft.
.WED...S wind 25 kt. Seas 17 ft.
.THU...SE wind 30 kt. Seas 16 ft.
.FRI...SE wind 25 kt. Seas 20 ft.

$$

PKZ177-201245-
Adak to Kiska-
246 PM AKST Sun Dec 19 2021

...GALE WARNING MONDAY NIGHT...

.TONIGHT...SW wind 30 kt. Seas 19 ft.
.MON...SW wind 15 kt becoming E 25 kt in the afternoon. Seas 15 ft.
.MON NIGHT...E wind 45 kt. Bering side, seas 9 ft building to 17
ft after midnight. Pac side, seas 22 ft. Rain and snow.
.TUE...SE wind 45 kt. Seas 22 ft.
.TUE NIGHT...S wind 40 kt. Seas 23 ft.
.WED...S wind 35 kt. Seas 19 ft.
.THU...SE wind 25 kt. Seas 14 ft.
.FRI...NE wind 20 kt. Seas 17 ft.

$$

PKZ178-201245-
Kiska to Attu-
246 PM AKST Sun Dec 19 2021

...STORM WARNING MONDAY NIGHT...

.TONIGHT...SW wind 30 kt. Seas 21 ft.
.MON...S wind 20 kt. Seas 16 ft.
.MON NIGHT...E wind 35 kt increasing to 50 kt after midnight.
Bering side, seas 9 ft building to 17 ft after midnight. Pac side, 
seas 14 ft building to 25 ft after midnight. Rain and snow.
.TUE...E wind 50 kt. Seas 24 ft.
.TUE NIGHT...S wind 45 kt. Seas 21 ft.
.WED...S wind 40 kt. Seas 23 ft.
.THU...S wind 25 kt. Seas 19 ft.
.FRI...N wind 20 kt. Seas 12 ft.

$$

PKZ179-201245-
Pribilof Islands Near Shore Waters-
246 PM AKST Sun Dec 19 2021

...SMALL CRAFT ADVISORY THROUGH MONDAY NIGHT...

.TONIGHT...SW wind 30 kt diminishing to 15 kt after midnight.
Seas 19 ft subsiding to 14 ft after midnight.
.MON...W wind 25 kt. Seas 13 ft.
.MON NIGHT...W wind 25 kt becoming N 15 kt after midnight.
Seas 13 ft.
.TUE...E wind 30 kt. Seas 8 ft.
.TUE NIGHT...SE wind 35 kt. Seas 13 ft.
.WED...SW wind 30 kt. Seas 13 ft.
.THU THROUGH FRI...SE wind 20 kt. Seas 11 ft.

$$

PKZ180-201245-
Kuskokwim Delta and Etolin Strait-
246 PM AKST Sun Dec 19 2021

...SMALL CRAFT ADVISORY THROUGH MONDAY NIGHT...

.TONIGHT...S wind 30 kt. Seas in ice free waters 13 ft. Rain.
.MON AND MON NIGHT...W wind 25 kt. Seas in ice free waters 9 ft.
.TUE...N wind 15 kt. Seas in ice free waters 6 ft.
.TUE NIGHT...E wind 30 kt. Seas in ice free waters 4 ft.
.WED...SW wind 30 kt. Seas in ice free waters 7 ft.
.THU THROUGH FRI...S wind 20 kt. Seas in ice free waters 6 ft.

$$

PKZ181-201245-
North and West of Nunivak Island-
246 PM AKST Sun Dec 19 2021

...BRISK WIND ADVISORY THROUGH MONDAY NIGHT...

.TONIGHT...SW wind 30 kt.
.MON...SW wind 20 kt increasing to 30 kt in the afternoon.
.MON NIGHT...W wind 25 kt becoming NW 15 kt after midnight.
.TUE...E wind 15 kt.
.TUE NIGHT...E wind 30 kt.
.WED...SW wind 30 kt.
.THU THROUGH FRI...S wind 20 kt.

$$

PKZ185-201245-
Saint Matthew Island Waters-
246 PM AKST Sun Dec 19 2021

...SMALL CRAFT ADVISORY THROUGH MONDAY NIGHT...

.TONIGHT...SW wind 30 kt. Seas 21 ft.
.MON...SW wind 30 kt. Seas 18 ft. Rain showers.
.MON NIGHT...E of Saint Matthew Island, NW wind 25 kt diminishing
to 15 kt after midnight. W of Saint Matthew Island, W wind 15 kt. 
Seas 14 ft.
.TUE...E wind 35 kt. Seas 9 ft.
.TUE NIGHT...E wind 45 kt. Seas 16 ft.
.WED...E wind 40 kt. Seas 22 ft.
.THU...SE wind 20 kt. Seas 19 ft.
.FRI...S wind 15 kt. Seas 10 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
427 PM AKST Sat Dec 18 2021

.ANALYSIS AND UPPER LEVELS...

The weather over southern Alaska late this afternoon revolves
around a large North Pacific ridge that has its axis over the
eastern Bering Sea and northward toward the Bering Strait. The
250 mb jet stream is running up and over the northern part of
the ridge and then turns back toward the southeast bringing
northerly flow aloft over Southcentral Alaska this afternoon and
evening. This is a fairly strong jet with speeds around 140 to 160
kts. Ahead of this ridge, a shortwave is over the Copper River
Basin and heading toward the Alcan border. the subsidence behind
the shortwave and ahead of the amplifying ridge is keeping
widespread stratus over Cook Inlet through the Susitna Valley.

A strong surface low just east of Kamchatka is interacting with
the surface ridge over Southwest Alaska to bring in strong
southwesterly flow for both the surface and aloft over most of
the Bering Sea. This is increasing the amount of warm air flowing
into the region.

&&

.MODEL DISCUSSION...

Models are in good synoptic agreement across Southcentral and
Southwest mainland Alaska regions through the middle of next
week. The main issue is with some important differences in
temperatures aloft which will impact precipitation-type,
especially in Southwest AK and the southern Kenai Peninsula. An
example of this can be seen with the MOS temperature for Homer on
Monday. The latest data for the GFS and NAM show a 14 degree
difference in expected high temperatures with one in the lower 30s
and keeping precip all snow and the other in the mid 40s with
rain.

For the Bering Sea and Aleutians, models are also in good synoptic
agreement through the weekend. However, by Monday night there is
a significant spread in the track and intensity of the low moving
into the southwest Bering Sea from the North Pacific. As long as
the GEM is not used, the differences can be adjusted to give a
reasonable forecast for the Bering/Aleutians from the other
models.

&&

.AVIATION...
PANC...With a ridge quickly building in from the west tonight and
stratus firmly entrenched, it seems likely that low ceilings will
hold in place for much of the next 24 hours. Expect ceilings to
hover in the IFR to low end MVFR range. There could be some
improvement in ceilings during the day Sunday as a weak short-
wave moves through, but if so it likely won't be much improvement.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3:
Tonight through Tue afternoon)...

The upper level trough that brought light snow to much of
Southcentral earlier today continues to push off to the east,
taking the moisture with it. Some light snow was being observed
in Gulkana this afternoon which is expected to continue through
around 9 PM this evening when the axis of the upper level trough
passes through. Elsewhere across Southcentral, heights begin to
build as yet another transient upper level ridge moves overhead.
Some areas have cleared out as a result of the upper level ridge
moving overhead such as Skwentna south to Beluga Point with even
Kenai seeing partly cloudy skies currently. However, the low
stratus that is currently in place is expected to linger through
the evening and into the overnight hours across the interior parts
of the Kenai Peninsula, the Anchorage Bowl and Matanuska Valley.
Low level moisture is expected to remain trapped keeping the cloud
cover in place. Also, as a result of this some pockets of isolated
freezing drizzle are possible through the evening hours. Expect
gusty gap winds through Whittier, Seward, Thompson Pass, and the
Valdez area also due to cold air advection on the backside of the
trough as well as tightening pressure gradients this evening and
through the day on Sunday.

Sunday through Sunday night will remain fairly quiet across much
of Southcentral as the upper level ridge remains overhead. Partly
to mostly cloudy skies are also expected as some breaks in the
clouds are anticipated as some of the low level moisture is
scoured out. Temperatures area-wide will generally be in the teens
and 20s with the exception of the Copper River Basin where highs
will mostly be in the single numbers.

Then things get interesting for early Monday through Monday night.
Deep southwesterly to west-southwesterly flow is expected to
develop Sunday night ahead of a vigorous upper level shortwave
across Southwest Alaska. This will advect moisture up the Cook
Inlet to the Mat-Su Valleys, Anchorage Bowl, and the Kenai
Peninsula. As a result, a heavier snowfall than that of recent is
expected for Monday through Monday night. However, amounts still
remain very much in question due to timing differences on how
quick this moves through as well as how much moisture is
available. Either way, expect more snow on Monday but stay tuned
to the forecast as we continue to iron out how much snow will fall
in certain areas. One other forecast challenge with this system
is the amount of warm air that will be present ahead of the system
for places like Homer and Seldovia. Right now, think a rain/snow
mix will suffice but if enough warm air can move in then there is
a chance these areas see some rain with this system. Also, as warm
air aloft moves up the Kenai Peninsula, surface temperatures may
fail to rise above freezing especially across the interior part of
the Peninsula potentially resulting in freezing rain for a time
Monday. Then the question becomes will this make it as far north
as the Sterling Highway to impact between Soldotna and Cooper
Landing. Stay tuned as there still is a great deal of information
to be sorted out over the next 24-36 hours.

After Monday night, as the upper level shortwave continues to
dive to the southeast, strong cold air advection is expected on
the backside for the rest of Monday night through the day Tuesday
with strong gusty winds expected through the typical terrain gaps
(i.e. Seward, Whittier, Valdez, Thompson Pass, Barren Islands
area, and Shelikof Strait).

&&

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

A warm front has begun to move ashore along the Southwest coast
this evening, with snow presently falling across much of the
Kuskokwim Delta. Precipitation type continues to be the main
challenge with this front, with questions remaining regarding
when and where conditions may become favorable for freezing rain.
The current thinking is that the relatively warm pre-existing
temperatures ahead of the front and the strong southerly push of
warm air with the front should result in a smooth transition to
rain with little to no sleet or freezing rain in the Kuskokwim
Delta. The transition to rain is expected to primarily occur
behind the bulk of the precipitation across most of Southwest
Alaska, with snow falling along the main front this evening for
the Kuskokwim Delta and Bristol Bay, and lighter rain and
rain/snow mix showers moving in behind the front early Sunday
morning. Northwestern portions of the Kuskokwim Delta will be
the exception, where some fraction of the initial push of
precipitation with the front is likely to be rain. The surge of
warm, moist air behind the warm front may lead to widespread low
stratus or fog over the Bering which would move onshore Sunday
morning.

Behind the front, temperatures rise into the mid to upper 30s for
the Kuskokwim Delta and Bristol Bay. A cold front then moves
ashore from the west on Sunday evening. With the warm sector
airmass in place, precipitation looks to be primarily rain for
the Kuskokwim Delta and most of Bristol Bay with warm, southerly
flow ahead of the front. However, there is the possibility that
warmer air does not work into the Lower Kuskokwim Valley,
particularly near Sleetmute. If surface temperatures remain
cooler there, a period of freezing rain or sleet will be possible
as the cold front begins to move through Sunday night, before
precipitation turns to snow. Rain and snow clear out eastward
through Monday, making for a quieter Monday night and Tuesday,
although a strong passing shortwave may bring scattered snow
showers to the Kuskokwim Delta and Valley.

&&

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

A wide swath of southerly gale force winds is present across much
of the Bering Sea this evening, bringing warm, moist air from the
North Pacific. A strong front pushes east through the western and
central Aleutians tonight and tomorrow, bringing rain and gusty
winds to the islands. The front weakens as it pushes into the
eastern Aleutians by Sunday night, but continues to produce rain
and gusty winds there. On Monday, a surface anticyclone moves in
across most of the Aleutians and Bering, bringing calmer, drier
conditions. By Monday night, a strong front ahead of a low in the
North Pacific enters the western and central Bering/Aleutians,
bringing rain and gusty gale force easterlies.

&&

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

Gulf of Alaska: Forecast confidence has greatly increased for
Tuesday, with a deeper surface low crossing the Gulf and moderate
to strong cold air advection behind it. This will lead to
widespread gale force winds across the Gulf waters, with strong
and gusty winds through bays and passes. There is some potential
for a period of storm force winds, especially in the Kamishak Bay
to Barren Islands corridor. Winds will diminish a bit on
Wednesday, but another shot of cold air advection is likely on
Thursday, so winds will strengthen again by Thursday - likely
reaching gale force in a lot of areas once again.

Bering Sea: Another deep low will track into the far western
bering Sea on Tuesday. While there is some uncertainty in the
track and depth of the low, it looks like a very large system
which will impact much of the Bering Sea and Aleutians. The
forecast largely indicates widespread gale force winds, but there
is good potential for smaller areas of storm force winds -
especially along the western Aleutians. Smaller and weaker systems
will follow quickly behind the first storm for Wednesday and
Thursday. It's too early to nail down the details for these
storms, but it looks like they will top out at gale force winds
and will affect a much smaller area.

&&

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

There is a high degree of ensemble agreement that an Omega Block
will extend across the North Pacific during the extended period.
The ridge-axis is expected to extend northward from the central
North Pacific to over Southwest Alaska. This upper level pattern
will then continue to persist for the remainder of the extended
period. This will lead to warmer temperatures across Southwest
Alaska and the Alaska Peninsula. Temperatures will be cooler
across Southcentral when compared to Southwest due to broadscale
northwesterly flow to the east of the ridge-axis. Mostly sunny
skies will continue across Southcentral due to strong subsidence.
This pattern will also allow for cold nights across Southcentral
due to clear skies and light winds which will allow for effective
radiational cooling.

The predominant storm track is expected to extend northeastward
across the Bering Sea and into the Bering Strait/Seward Peninsula.
This will allow a couple of warm fronts associated with lows to
move across Southwest Alaska during this period. The first front
will be on Wednesday, second will be on Friday and third will be
later on Saturday. There is low forecast confidence at this time
with respect to the specifics of weather with these fronts,
though temperatures will likely be warm enough across Southwest
to see a variety of precipitation-types. Chances for rain will be
higher in low-lying coastal areas while snow chances will be higher
across interior locations such as the lower Kuskokwim Valley and
the higher elevations of the Kuskokwim and Alaska ranges.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Gale warning 131 132 170 173 174 175 176
                      177 178 179 181 185.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...EZ
SOUTHCENTRAL ALASKA...MV
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...CQ
MARINE/LONG TERM...ED/SEB