Storm Warning 193, NWS Anchorage, AK

425 
FZAK52 PAFC 300051
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
351 PM AKST Sun Nov 29 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.

PKZ199-301345-
351 PM AKST Sun Nov 29 2020
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 959 mb low 315 nm south of Adak moves to 85 nm South of 
Sitkinak at 972 mb by Tue afternoon. Its front moves over the 
Aleutians into Southwest Alaska for Tue afternoon. A 1005 mb 
Kamchatka low moves to become a 989 mb low complex 100 nm 
Southwest of Attu by Tue afternoon. Its front moves over the 
Western Aleutians through Tue afternoon.

$$

PKZ150-301345-
South of the AK Peninsula Sitkinak to Castle Cape-
351 PM AKST Sun Nov 29 2020

...GALE WARNING THROUGH MONDAY...

.TONIGHT...SW wind 20 kt becoming SE 40 kt after midnight. Seas
10 ft. Snow and rain.
.MON...E wind 40 kt becoming SW 25 kt by afternoon. Seas 15 ft. Rain
and snow.
.MON NIGHT...S wind 25 kt. Seas 15 ft building to 18 ft after 
midnight. Rain showers.
.TUE AND TUE NIGHT...NW wind 25 kt. Seas 17 ft.
.WED...W wind 20 kt. Seas 13 ft.
.THU...NW wind 20 kt. Seas 10 ft.
.FRI...W wind 15 kt. Seas 14 ft.

$$

PKZ155-301345-
South of the AK Peninsula Castle Cape to Cape Sarichef-
351 PM AKST Sun Nov 29 2020

...GALE WARNING THROUGH MONDAY NIGHT...

.TONIGHT...E wind 45 kt. From the Shumagin Islands E, SE wind 25
kt becoming E 40 kt after midnight. Seas 8 ft building to 13 ft after
midnight. Snow showers and rain showers.
.MON...NE wind 35 kt. From the Shumagin Islands E, SE wind 40 kt
becoming S 20 kt in the afternoon. Seas 14 ft.
.MON NIGHT...N wind 35 kt except SW 20 kt from the Shumagin
Islands E becoming N 20 kt after midnight. Seas 19 ft. Rain showers.
.TUE...NW wind 30 kt. Seas 16 ft.
.TUE NIGHT...NW wind 30 kt. Seas 12 ft.
.WED...NW wind 20 kt. Seas 10 ft.
.THU...NW wind 15 kt. Seas 7 ft.
.FRI...NW wind 15 kt. Seas 14 ft.

$$

PKZ160-301345-
Bristol Bay-
351 PM AKST Sun Nov 29 2020

...GALE WARNING MONDAY AND MONDAY NIGHT...

.TONIGHT...Variable wind 10 kt becoming E 20 kt after midnight. Seas
5 ft. Freezing spray.
.MON...NE wind 40 kt. Seas 5 ft building to 11 ft by afternoon. 
Freezing spray. Snow showers.
.MON NIGHT...N wind 35 kt becoming NW 20 kt after midnight. Seas
9 ft subsiding to 5 ft after midnight. Freezing spray. Snow and rain
showers.
.TUE AND TUE NIGHT...NW wind 20 kt. Seas 6 ft.
.WED THROUGH THU...N wind 20 kt. Seas 5 ft.
.FRI...N wind 15 kt. Seas 4 ft.

$$

PKZ165-301345-
Port Heiden to Cape Sarichef-
351 PM AKST Sun Nov 29 2020

...GALE WARNING THROUGH MONDAY NIGHT...

.TONIGHT...E wind 25 kt becoming NE 35 kt after midnight. From
Port Moller E, variable wind 10 kt becoming E 25 kt after midnight. 
Seas 8 ft.
.MON...NE wind 40 kt. Seas 11 ft building to 16 ft by afternoon. 
Snow showers.
.MON NIGHT...N wind 40 kt. Seas 18 ft. Freezing spray.
.TUE...N wind 35 kt. Seas 16 ft.
.TUE NIGHT...NW wind 30 kt. Seas 13 ft.
.WED...NW wind 25 kt. Seas 12 ft.
.THU...N wind 25 kt. Seas 8 ft.
.FRI...N wind 20 kt. Seas 6 ft.

$$

PKZ170-301345-
Cape Sarichef to Nikolski Bering Side-
351 PM AKST Sun Nov 29 2020

...GALE WARNING THROUGH MONDAY NIGHT...

.TONIGHT...NE wind 45 kt. Seas 10 ft building to 14 ft after midnight.
.MON...NE wind 45 kt. Seas 16 ft building to 19 ft by afternoon.
.MON NIGHT...N wind 40 kt. Seas 19 ft.
.TUE...N wind 35 kt. Seas 17 ft.
.TUE NIGHT...N wind 30 kt. Seas 13 ft.
.WED...N wind 15 kt. Seas 10 ft.
.THU THROUGH FRI...N wind 20 kt. Seas 7 ft.

$$

PKZ171-301345-
Unalaska Bay-
351 PM AKST Sun Nov 29 2020

...GALE WARNING THROUGH MONDAY NIGHT...

.TONIGHT...NE wind increasing to 40 kt. Seas 5 ft building to 12 ft 
after midnight. Snow showers.
.MON...NE wind 40 kt. Seas 15 ft. Snow showers.
.MON NIGHT...N wind 35 kt. Seas 16 ft subsiding to 13 ft after
midnight. Snow showers.
.TUE...NW wind 30 kt. Seas 13 ft.
.TUE NIGHT...NW wind 25 kt. Seas 10 ft.
.WED...N wind 10 kt. Seas 3 ft.
.THU...N wind 15 kt. Seas 5 ft.
.FRI...N wind 10 kt. Seas 3 ft.

$$

PKZ172-301345-
Cape Sarichef to Nikolski Pacific Side-
351 PM AKST Sun Nov 29 2020

...GALE WARNING THROUGH MONDAY NIGHT...

.TONIGHT...E wind 45 kt. Seas 14 ft building to 18 ft after midnight.
Rain showers and snow showers.
.MON...NE wind 45 kt. Seas 19 ft building to 23 ft by afternoon. 
Snow showers and rain showers.
.MON NIGHT...N wind 40 kt. Seas 21 ft subsiding to 17 ft after
midnight.
.TUE...NW wind 35 kt. Seas 15 ft.
.TUE NIGHT...NW wind 30 kt. Seas 10 ft.
.WED THROUGH FRI...N wind 15 kt. Seas 9 ft.

$$

PKZ173-301345-
Nikolski to Seguam Island Bering Side-
351 PM AKST Sun Nov 29 2020

...GALE WARNING THROUGH MONDAY NIGHT...

.TONIGHT...NE wind 45 kt. Seas 18 ft. Snow and rain showers.
.MON...N wind 40 kt. Seas 20 ft.
.MON NIGHT...N wind 35 kt. Seas 19 ft subsiding to 15 ft after
midnight.
.TUE...N wind 25 kt. Seas 13 ft.
.TUE NIGHT...N wind 15 kt. Seas 10 ft.
.WED THROUGH FRI...NE wind 15 kt. Seas 8 ft.

$$

PKZ174-301345-
Nikolski to Seguam Island Pacific Side-
351 PM AKST Sun Nov 29 2020

...STORM WARNING TONIGHT...

.TONIGHT...NE wind 50 kt. Seas 18 ft building to 25 ft after 
midnight. Rain showers and snow showers.
.MON...N wind 45 kt. Seas 29 ft subsiding to 25 ft by afternoon.
.MON NIGHT...N wind 40 kt diminishing to 30 kt after midnight.
Seas 22 ft subsiding to 16 ft after midnight.
.TUE...N wind 25 kt. Seas 13 ft.
.TUE NIGHT...N wind 15 kt. Seas 9 ft.
.WED...NE wind 20 kt. Seas 7 ft.
.THU THROUGH FRI...NE wind 15 kt. Seas 11 ft.

$$

PKZ175-301345-
Seguam Island to Adak Bering Side-
351 PM AKST Sun Nov 29 2020

...GALE WARNING THROUGH MONDAY...

.TONIGHT...NE wind 45 kt. Seas 20 ft. Rain showers.
.MON...N wind 40 kt. Seas 19 ft subsiding to 16 ft by afternoon.
.MON NIGHT...N wind 30 kt diminishing to 20 kt after midnight.
Seas 15 ft subsiding to 12 ft after midnight.
.TUE...N wind 15 kt. Seas 11 ft.
.TUE NIGHT...E wind 15 kt. Seas 9 ft.
.WED THROUGH THU...NE wind 15 kt. Seas 7 ft.
.FRI...E wind 20 kt. Seas 6 ft.

$$

PKZ176-301345-
Seguam Island to Adak Pacific Side-
351 PM AKST Sun Nov 29 2020

...STORM WARNING TONIGHT...

.TONIGHT...NE wind 50 kt. Seas 22 ft building to 29 ft after
midnight. Rain showers.
.MON...N wind 40 kt. Seas 28 ft subsiding to 22 ft in the
afternoon.
.MON NIGHT...N wind 35 kt diminishing to 25 kt after midnight.
Seas 19 ft subsiding to 13 ft after midnight.
.TUE...NW wind 20 kt. Seas 10 ft.
.TUE NIGHT...E wind 15 kt. Seas 8 ft.
.WED...E wind 20 kt. Seas 7 ft.
.THU...N wind 15 kt. Seas 9 ft.
.FRI...NE wind 20 kt. Seas 10 ft.

$$

PKZ177-301345-
Adak to Kiska-
351 PM AKST Sun Nov 29 2020

...STORM WARNING TONIGHT...

.TONIGHT...NE wind 50 kt becoming N 40 kt after midnight. Seas 20
ft Bering side...28 ft Pacific side.
.MON...N wind 30 kt. Seas 19 ft subsiding to 13 ft in the
afternoon.
.MON NIGHT...N wind 20 kt in the evening becoming variable 10 kt.
Seas 11 ft.
.TUE...Variable wind 10 kt. Seas 8 ft.
.TUE NIGHT...SE wind 15 kt. Seas 8 ft.
.WED...E wind 20 kt. Seas 7 ft.
.THU...Variable wind 10 kt. Seas 9 ft.
.FRI...E wind 15 kt. Seas 7 ft.

$$

PKZ178-301345-
Kiska to Attu-
351 PM AKST Sun Nov 29 2020

...GALE WARNING TONIGHT...

.TONIGHT...N wind 35 kt diminishing to 25 kt after midnight. Seas
24 ft subsiding to 18 ft after midnight.
.MON...NE wind 20 kt in the morning becoming variable 10 kt. Seas
12 ft.
.MON NIGHT...SE wind 15 kt. Seas 9 ft.
.TUE...S wind 15 kt. Seas 7 ft.
.TUE NIGHT...Variable wind 10 kt. Seas 7 ft.
.WED...Variable wind 10 kt. Seas 9 ft.
.THU...SW wind 15 kt. Seas 9 ft.
.FRI...Variable wind 10 kt. Seas 6 ft.

$$

PKZ179-301345-
Pribilof Islands Near Shore Waters-
351 PM AKST Sun Nov 29 2020

...GALE WARNING MONDAY...

.TONIGHT...NE wind 20 kt in the evening increasing to 30 kt. Seas
building to 10 ft.
.MON...NE wind 35 kt. Seas 11 ft building to 14 ft by afternoon.
.MON NIGHT...N wind 30 kt. Seas 14 ft.
.TUE...N wind 30 kt. Seas 12 ft.
.TUE NIGHT...N wind 20 kt. Seas 10 ft.
.WED THROUGH FRI...NE wind 15 kt. Seas 7 ft.

$$

PKZ180-301345-
Kuskokwim Delta and Etolin Strait-
351 PM AKST Sun Nov 29 2020

...GALE WARNING MONDAY AND MONDAY NIGHT...
...HEAVY FREEZING SPRAY WARNING THROUGH MONDAY NIGHT...

.TONIGHT...NE wind 25 kt. Seas 6 ft. Heavy freezing spray near the
coast.
.MON...NE wind 30 kt becoming N 40 kt in the afternoon. Seas 11
ft. Heavy freezing spray near the coast.
.MON NIGHT...N wind 45 kt. Seas 13 ft. Heavy freezing spray.
.TUE...N wind 35 kt. Seas 12 ft.
.TUE NIGHT...N wind 30 kt. Seas 11 ft.
.WED THROUGH FRI...N wind 25 kt. Seas 8 ft.

$$

PKZ181-301345-
North and West of Nunivak Island-
351 PM AKST Sun Nov 29 2020

...GALE WARNING MONDAY NIGHT...
...HEAVY FREEZING SPRAY WARNING THROUGH MONDAY NIGHT...

.TONIGHT...N wind 25 kt. Seas 8 ft. Heavy freezing spray near the 
coast.
.MON...N wind 30 kt. Seas 8 ft. Heavy freezing spray near the 
coast.
.MON NIGHT...N wind 35 kt. Seas 12 ft. Heavy freezing spray.
.TUE...N wind 35 kt. Seas 13 ft.
.TUE NIGHT...NW wind 30 kt. Seas 11 ft.
.WED...NW wind 25 kt. Seas 8 ft.
.THU THROUGH FRI...N wind 20 kt. Seas 6 ft.

$$

PKZ185-301345-
Saint Matthew Island Waters-
351 PM AKST Sun Nov 29 2020

...SMALL CRAFT ADVISORY MONDAY AND MONDAY NIGHT...

.TONIGHT...N wind 20 kt. Seas 7 ft. Freezing spray.
.MON...N wind 25 kt. Seas 8 ft. Freezing spray.
.MON NIGHT...N wind 30 kt E of Saint Matthew Island... N 20 kt W
of Saint Matthew Island. Seas 10 ft. Freezing spray.
.TUE...N wind 30 kt. Seas 10 ft.
.TUE NIGHT...N wind 25 kt. Seas 9 ft.
.WED...N wind 20 kt. Seas 6 ft.
.THU THROUGH FRI...NE wind 20 kt. Seas 5 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
520 PM AKST Sat Nov 28 2020

.ANALYSIS AND UPPER LEVELS...

The upper level pattern continues to present a complex longwave
trough over our forecast area. This trough has shifted east over
the past day and is now centered over Southwest AK and encompasses
almost all of our forecast area, save for a shortwave ridge over
the Western Aleutians. A couple of closed upper low centers exist
within this longwave, with one of the lows centered over the
AKPEN. Several shortwave troughs are also embedded in this flow.
There are two prominent shortwaves in our forecast area. One
weakening trough in the Bering supporting a decaying surface low
over the Aleutians. The other is over the Gulf of Alaska
supporting a surface low moving into the Southcentral Gulf Coast.

On the surface, radar is capturing precipitation associated with
the low along the Gulf of Alaska moving into Southcentral AK.
Surface observations are also showing the trough moving in, with
continued snowfall in areas like Portage and Whittier. Slightly
warmer areas farther south on the coast like Homer are seeing a
mix of snow and rain. The latest low center has pushed ashore near
Yakutat, with the next low right on its heels, currently located
south of Kodiak. In southwest, radar also shows wrap around
moisture in Bristol Bay from this system. A weak decaying low is
currently moving south through the Bering and not producing much
weather.

&&

.MODEL DISCUSSION...

As with the past few days, models are handling synoptic features
well in the short term and depicting the longwave pattern well.
They are continuing to struggle on the mesoscale and with local
effects, especially for Southcentral AK. There has been almost
continuous adjustment to the forecast the past couple of days as
a result. Today is a little better, in part because the pattern
has briefly quieted. However, models still struggle after about
48 hours. In our western domain, models are performing better. So,
we have high confidence in models out west, with lower confidence
in Southcentral.

&&

.AVIATION...

PANC...VFR conditions and light winds will persist.

&&

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

A gigantic area of low pressure east of Kodiak Island remains to
be the primary weather producer for Southcentral this afternoon.
A weakening frontal zone over Prince William Sound (PWS) continues
lifting inland and dissipating. Still, more snowfall from this
feature will spread across PWS and Copper River Basin, including
Thompson Pass tonight. A shortwave behind this frontal axis will
arrive across PWS and eastern Kenai Peninsula later tonight while
the upper level low make its way toward the northern Gulf and
inland (east of Cordova) overnight tonight. Once this upper low
moves inland and well east of PWS later tonight, snowy conditions will
taper off over much of the area east of the Anchorage Bowl. This
will last only for a short while before the next upper level
system arrives Sunday morning.

Over Shelikof Strait, a developing upper low is parked there
before moving toward PWS Sunday morning. This will cause another
heavy round of heavy mixing rain and snow to return by late
Sunday afternoon if not sooner over PWS and the Copper River
Basin. Meanwhile, a shortwave north of the upper low will break
away and drift northward past Anchorage Bowl by Sunday night. In
response, more snow will spread over Anchorage, Matanuska Valley
and western Kenai Peninsula on Sunday and Sunday night.

Temperature-wise, most of the area will stay at or above normal
this weekend, though Sunday night into Monday could offer a brief
return to colder, more normal temperatures. This will be brief,
however, because the next low in this parade of storms looks to
bring much warmer conditions and rain chances to much of Southcentral
by early next week.

&&

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

An upper level low continues to spin over the region with its
associated surface low to the east of Kodiak Island. The surface
low will continue moving northward through the Gulf of Alaska
while weakening. However, energy associated with the upper level
low is keeping light snow and low visibilities across the
Kuskokwim Mountains and across northern and central Bristol Bay in
areas such as Koliganek and New Stuyahok. This energy will only
ever so slowly move southward out of the region heading into the
overnight hours. Therefore, light snow was kept in the forecast
with some accumulation until Sunday morning before finally
dissipating. Due to the light snow, only an additional inch of
snow accumulation is anticipated. Radar imagery was showing some
returns possibly making it into the Bethel area this afternoon
through the evening hours. With this in mind, we opted to just
put flurries in the forecast as some moisture may make it into the
area.

This system finally pulls away by late Sunday morning. Skies are
expected to clear the most out over the Yukon-Kuskokwim Delta
with partly cloudy to mostly cloudy skies elsewhere. With the
recent snow and residual moisture in the air, areas of patchy fog
are possible for Monday morning. Other than that, expect a dry but
cold Sunday afternoon through Monday morning before the next
system approaches. Temperatures Sunday afternoon across the
interior areas are expected to be in the upper single digits and
teens with 20s along the coast. Temperatures will become very cold
for Monday morning with single digits below zero across the
interior areas and single numbers and teens along the coastal
areas. The one thing possibly going against it getting this cold
Monday morning is the potential cloud cover that may be around. If
skies clear, the potential is there for temperatures to fall even
further than already forecast. Also, areas of patchy fog will
also play a role in the temperatures for Monday morning.

Lastly, the next storm system moves into the area Monday morning
and continues to affect the area through Tuesday night. This event
should be all snow for areas west of a Lime Village to Koliganek
to New Stuyahok to Dillingham line. Areas east of the
aforementioned line have the potential for a snow changing to rain
situation as warmer air comes in and then back to snow when the
cold air comes back in. These areas may also just mix with rain
briefly especially areas around Iliamna. King Salmon is a tough
forecast for this system as the gradient between warm and cold is
expected to be sharp making any shift in the storm track
detrimental to the type of precipitation that will fall. A further
west track means more rain and warmer for King Salmon with
further east colder and more snow. Of course, the downsloping risk
is there as well with this system and depending on how strong the
downsloping is will factor into the amount of precipitation seen.
Interior Bristol Bay and the Middle Kuskokwim Valley have the
potential to see significant snowfall (greater than 6 inches) from
this event where a band of snow might set up. Where this band
sets up remains in question but where it does could see
significant snowfall and headlines will be possible with the
coming forecast packages.

&&

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

Cold air flowing over the Bering is creating an unstable
atmospheric setup. This is seen on visible satellite imagery in
the form of cumulus clouds. Some of these grow enough to cause
snow showers that may briefly reduce visibility and lower
ceilings for the Pribilofs and the eastern Aleutian Chain (Cold
Bay and Sand Point). This will continue for the duration of this
forecast package, especially for the Pribilofs north and west.

The next weather system is expected to affect the areas mainly
south and west of the Pribilofs with storm force winds especially
in the marine zones south of the Aleutian Chain. The timing on
these storm force winds are expected to be early Sunday morning
through Monday morning. Seas of 20-30 ft are expected south of the
Chain with 16-21 ft seas for the Bering side. The one other thing
to note is the potential for blowing snow Monday afternoon into
early Tuesday for the eastern Aleutians as the cold air is coming
back in and precipitation is still occurring. The better risk for
this is around Cold Bay and False Pass which will have a better
chance of keeping the cold air in place. Sand Point has the
better risk to have rain occurring and having the precipitation
shut off before the winds ramp up Tuesday morning for any blowing
snow to occur.

&&

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

Gulf: A well-developed low moves over the Western Gulf through
Thu. Its model track and development are mixed with the wrapped
low as it weakens. However, widespread southerly high-end small
craft winds and waves with local areas of gale force winds move
over the Gulf through Thu. These winds will diminish to
southwesterly small craft over the Gulf and local southeasterly
small craft winds around the Barren Islands, Kamishak Bay and
lower Cook Inlet.

Bering: A well-developed low moves into the Gulf of Alaska weakens
by Thu. The model track and development of the wrapped low vary
through Thu. Northerly gale force winds and waves over the
Central and Eastern Bering and Alaska Peninsula diminish to small
craft winds over the Eastern Bering and West Coast waters. Cold
high pressure dips into the Bering for Thu, but an upper level
trough brings easterly small craft winds to the West of St Matthew
Island Wed and Thu.

&&

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

A weakening low pushes through Cook Inlet on Wednesday, keeping
the Southcentral coastal areas under showery conditions.
850mb temperatures remain warm enough to keep precipitation as all
rain, followed by a brief period of rain/snow mix on Thursday.
Models differ slightly with this low, where the Canadian/ECMWF
dissipate the low as it makes its way onshore, while the GFS
lingers it over Bristol Bay through Friday. This will have an
impact on a second low that enters the Southern Gulf by Thursday
afternoon where the GFS path is pushed more towards the Southeast
Coast. Both the Canadian and ECMWF solutions track this low north
towards the Southcentral Coast with slight differences between
strength and center location. These differences in model solutions
can impact precipitation type and intensity for the Southcentral
Coast for Friday and will need to be monitored over the next few
days. A third system tracks south of the Aleutians late next week
and will bring gusty winds to the central/eastern Aleutian Chain.
Additionally, persistent upper-level troughing lingers over the
Southwest region through Friday. Flow with this will be
predominantly northerly, thus, below average temperatures can be
expected over the Southwest mainland and the AKPEN/eastern
Aleutians.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Heavy Freezing Spray Warnings 160 180 181.
		 Storm Warning 172 174 175 176 177 178.
	     Gale Warning 150 155 160 165 170 171 173 132.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...BB
SOUTHCENTRAL ALASKA...CB
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MV
MARINE/LONG TERM...KM