Alert archive / Alaska / Storm Warnings in 2020

Storm Warning 139, NWS Anchorage, AK

November 22, 2020

NWS Anchorage, AK issued this storm warning at Nov 22, 2020, 3:58 AM AKST. It was in force for 48 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Nov 22, 2020, 3:58 AM AKST (12:58 UTC)
Expired
Nov 24, 2020, 3:56 AM AKST
In force
48 hr
Issued by
NWS Anchorage, AK

The text

As transmitted.

866 
FZAK61 PAFC 221258
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
358 AM AKST Sun Nov 22 2020

Offshore waters forecast for the Gulf of Alaska West of 144W

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.

PKZ399-230130-
358 AM AKST Sun Nov 22 2020
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...A 956 mb low will enter 
the western Gulf near 56N 151W Monday morning. The low then moves to 
54N 138W at 981 mb Tuesday morning. 


$$

PKZ351-230130-
Gulf of Alaska Offshore North of 57N and West of 144W-
358 AM AKST Sun Nov 22 2020

...STORM WARNING TONIGHT AND MONDAY...

.TODAY...SW wind 15 kt becoming S in the afternoon. Seas 9 ft.
.TONIGHT...SE wind 25 to 40 kt increasing to 35 to 50 kt after
midnight. Seas 10 to 18 ft. Rain.
.MON...SE wind 35 to 50 kt becoming E to NE 20 to 30 kt in the
afternoon. Seas 16 to 27 ft. Rain showers.
.MON NIGHT...N wind 25 to 40 kt. Seas 18 to 28 ft.
.TUE...W wind 20 to 35 kt. Seas 11 to 19 ft.
.WED THROUGH THU...SW wind 15 to 30 kt. Seas 9 to 17 ft.

$$

PKZ352-230130-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
358 AM AKST Sun Nov 22 2020

...STORM WARNING MONDAY...

.TODAY...SW wind up to 15 kt becoming SE 20 to 35 kt in the
afternoon. Seas 10 ft. Rain.
.TONIGHT...SE wind 30 to 45 kt. Seas 11 to 19 ft. Rain.
.MON...S to SE wind 35 to 50 kt becoming W to NW in the afternoon. 
Seas 18 to 33 ft building to 24 to 37 ft in the afternoon. Rain.
.MON NIGHT...NW wind 35 to 50 kt. Seas 22 to 36 ft.
.TUE...SW wind 20 to 35 kt. Seas 16 to 24 ft.
.WED THROUGH THU...SW wind 20 to 35 kt. Seas 12 to 20 ft.

$$
4 follow-up statements
447 
FZAK61 PAFC 230049
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
349 PM AKST Sun Nov 22 2020

Offshore waters forecast for the Gulf of Alaska West of 144W

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.

PKZ399-231400-
349 PM AKST Sun Nov 22 2020
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 954 mb low at 56N 154W Mon morning will move to 56N 146W at 960
mb Mon afternoon then will move into the southeast Gulf by Tue 
afternoon. A new front enters the southwest Gulf Tue afternoon.

$$

PKZ351-231400-
Gulf of Alaska Offshore North of 57N and West of 144W-
349 PM AKST Sun Nov 22 2020

...STORM WARNING THROUGH MONDAY...

.TONIGHT...SE wind 25 to 40 kt increasing to 35 to 50 kt after
midnight. Seas 12 to 19 ft. Rain.
.MON...SE wind 35 to 50 kt becoming E 15 to 30 kt in the
afternoon. Seas 16 to 27 ft. Rain.
.MON NIGHT...N wind 25 to 40 kt. Seas 18 to 28 ft. Rain showers.
.TUE...W wind 20 to 35 kt. Seas 13 to 21 ft.
.TUE NIGHT...SW wind 15 to 30 kt. Seas 8 to 13 ft.
.WED THROUGH THU...SW wind 20 to 35 kt. Seas 9 to 17 ft.
.FRI...SW wind 15 to 30 kt. Seas 6 to 11 ft.

$$

PKZ352-231400-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
349 PM AKST Sun Nov 22 2020

...STORM WARNING MONDAY AND MONDAY NIGHT...

.TONIGHT...SE wind 30 to 45 kt. Seas 9 to 15 ft building to 16 to 22
ft after midnight. Rain.
.MON...SW wind 35 to 50 kt. Seas 17 to 32 ft building to 26 to 37
ft in the afternoon. Rain.
.MON NIGHT...NW wind 35 to 50 kt. Seas 22 to 36 ft.
.TUE...W wind 25 to 40 kt. Seas 13 to 28 ft.
.TUE NIGHT...S wind 25 to 40 kt. Seas 11 to 17 ft.
.WED...SW wind 25 to 35 kt. Seas 13 to 21 ft.
.THU THROUGH FRI...SW wind 20 to 35 kt. Seas 10 to 15 ft.

$$
486 
FZAK61 PAFC 231256
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
356 AM AKST Mon Nov 23 2020

Offshore waters forecast for the Gulf of Alaska West of 144W

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.

PKZ399-240130-
356 AM AKST Mon Nov 23 2020
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...A 957 mb low at 57N
151W this morning will move to 54N 137W at 984 mb Tuesday morning. A
front moves across the Gulf of Alaska Tuesday night through 
Wednesday evening. 

$$

PKZ351-240130-
Gulf of Alaska Offshore North of 57N and West of 144W-
356 AM AKST Mon Nov 23 2020

...STORM WARNING TODAY...

.TODAY...SE wind 35 to 50 kt becoming S to E 15 to 30 kt in the
afternoon. Seas 17 ft building to 19 to 27 ft in the afternoon.
Rain.
.TONIGHT...NW wind 25 to 40 kt. Seas 19 to 28 ft. Rain showers.
.TUE...W wind 20 to 35 kt. Seas 13 to 21 ft.
.TUE NIGHT...S wind 15 to 30 kt. Seas 8 to 13 ft.
.WED THROUGH FRI...S wind 20 to 35 kt. Seas 9 to 17 ft.

$$

PKZ352-240130-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
356 AM AKST Mon Nov 23 2020

...STORM WARNING TONIGHT...

.TODAY...SW wind 30 to 45 kt. Seas 18 to 33 ft building to 25 to
37 ft in the afternoon. Rain.
.TONIGHT...SW to NW wind 35 to 50 kt. Seas 22 to 36 ft.
.TUE...W wind 25 to 40 kt diminishing to 20 to 30 kt in the
afternoon. Seas 14 to 28 ft.
.TUE NIGHT...S wind 25 to 40 kt. Seas 11 to 17 ft.
.WED THROUGH FRI...SW wind 20 to 35 kt. Seas 12 to 20 ft.

$$
270 
FZAK61 PAFC 240042
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
342 PM AKST Mon Nov 23 2020

Offshore waters forecast for the Gulf of Alaska West of 144W

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.

PKZ399-241415-
342 PM AKST Mon Nov 23 2020
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...
A 963 mb low at 57N 146W exits the Gulf to the southeast Tue
afternoon at 991 mb. A strong front enters the western Gulf 
Tue afternoon and reaches the northeastern Gulf Wed afternoon. 

$$

PKZ351-241415-
Gulf of Alaska Offshore North of 57N and West of 144W-
342 PM AKST Mon Nov 23 2020

...GALE WARNING THROUGH TUESDAY...

.TONIGHT...NW wind 25 to 40 kt. Seas 19 to 28 ft.
.TUE...W wind 20 to 35 kt. Seas 13 to 21 ft.
.TUE NIGHT...S wind 15 to 30 kt. Seas 10 to 14 ft.
.WED...S wind 30 to 40 kt. Seas 11 to 19 ft.
.WED NIGHT...SW wind 25 to 35 kt. Seas 15 to 20 ft.
.THU THROUGH FRI...S wind 20 to 35 kt. Seas 9 to 17 ft.
.SAT...S wind 20 to 30 kt. Seas 16 to 19 ft.

$$

PKZ352-241415-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
342 PM AKST Mon Nov 23 2020

...STORM WARNING TONIGHT...

.TONIGHT...NW wind 35 to 50 kt. Seas 23 to 37 ft.
.TUE...W wind 25 to 40 kt diminishing to 20 to 30 kt 
in the afternoon. Seas 13 to 28 ft.
.TUE NIGHT...S wind 25 to 40 kt. Seas 12 to 18 ft. Rain.
.WED...SW wind 25 to 40 kt. Seas 14 to 22 ft.
.WED NIGHT...W wind 20 to 30 kt. Seas 15 to 21 ft.
.THU THROUGH FRI...SW wind 20 to 35 kt. Seas 10 to 18 ft.
.SAT...S wind 20 to 30 kt. Seas 18 to 24 ft.

$$
072 
FZAK61 PAFC 241256
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
356 AM AKST Tue Nov 24 2020

Offshore waters forecast for the Gulf of Alaska West of 144W

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.

PKZ399-250130-
356 AM AKST Tue Nov 24 2020
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 977 mb low at 57N 139W exits the Gulf to the southeast by Tue 
afternoon at 992 mb. A strong front enters the western Gulf early 
Wednesday morning, reaching the northern Gulf Wed afternoon. A 980 mb
low will form along the front over Kennedy Entrance Wed afternoon, 
moving over the Prince William Sound at 990 mb Thu morning.

$$

PKZ351-250130-
Gulf of Alaska Offshore North of 57N and West of 144W-
356 AM AKST Tue Nov 24 2020

...GALE WARNING TODAY AND WEDNESDAY...

.TODAY...NW wind 20 to 35 kt becoming W in the afternoon. Seas 14
to 22 ft.
.TONIGHT...S wind 15 to 30 kt. Seas 9 to 14 ft. Rain.
.WED...S wind 25 to 35 kt. Seas 11 to 19 ft. Rain.
.WED NIGHT...W wind 30 kt. Seas 15 to 19 ft.
.THU...SW wind 10 to 25 kt. Seas 9 to 17 ft.
.FRI...S wind 10 to 25 kt. Seas 6 to 10 ft.
.SAT...S wind 15 to 30 kt. Seas 14 to 18 ft.

$$

PKZ352-250130-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
356 AM AKST Tue Nov 24 2020

...GALE WARNING THROUGH WEDNESDAY...

.TODAY...W wind 25 to 40 kt diminishing to 20 to 30 kt in the
afternoon. Seas 22 to 32 ft subsiding to 13 to 22 ft in the 
afternoon.
.TONIGHT...S wind 25 to 40 kt. Seas 12 to 19 ft. Rain.
.WED...SW wind 25 to 40 kt. Seas 15 to 23 ft. Rain.
.WED NIGHT...W wind 20 to 30 kt. Seas 15 to 20 ft.
.THU THROUGH FRI...SW wind 20 to 35 kt. Seas 9 to 17 ft.
.SAT...SW wind 15 to 30 kt. Seas 17 to 21 ft.

$$

What forecasters said that day

The local office's own words before this storm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Anchorage, AK wrote its last area forecast discussion before this storm warning went out at Nov 21, 5:00 PM AKST, 10 hours 58 minutes earlier.

Area forecast discussion, Nov 21, 5:00 PM AKST, 10 hours 58 minutes before
Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
500 PM AKST Sat Nov 21 2020

.ANALYSIS AND UPPER LEVELS...

Satellite shows low pressure just south of St Matthew Island with
a front extending into Southwest Alaska. Another low is  near the
Barren Islands and is weakening as it moves up Cook Inlet.

Radar imagery shows rain and snow bands moving northwestward
across the Kenai Peninsula and Prince William Sound with a few
stray bands of rain/snow moving across southern Cook Inlet. Radar
imagery also shows showers moving across Bristol Bay with snow
farther north near Iliamna. And some rain and snow showers across
the Kuskokwim Delta region. Temperatures are in the lower to mid
30s across Southwest Alaska but colder in the teens and twenties
as you head inland across the lower Kuskokwim valley. From Kodiak
Island to Homer area temperatures are in the upper 30s with some
areas of light rain reported, farther north lower to mid 30s
across Seward and Kenai up to Portage and Whittier with rain and
snow reported across this area. While the Anchorage and MAT-SU
valleys are in the mid 20s to near 30. Much colder in the Copper
River Basin where single digits to below zero are reported. Gusty
winds across the MAT valley and decent down inlet flow from the
north and northeast from Anchorage to Kenai.

&&

.MODEL DISCUSSION...

Models are in better agreement through Monday, and confidence is
increasing as the details begin to emerge. The biggest issue are
models are starting to pickup on possible Hurricane force winds in
the southwest quadrant of the low tracking across the Gulf on
Monday, for now we went with high end storms, but this will need
to be monitored closely.

&&

.AVIATION...
PANC...VFR conditions becoming MVFR with light snow near or after
midnight. Winds will become southeast this afternoon and increase
with gusts up to 20 knots as the front moves across the area
tonight. Some light snow accumulations are possible overnight
through the morning hours. Expect VFR conditions to return by
mid- day on Sunday.

&&

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

Rain/snow showers near the coast will taper off through the
evening as a low moves over Cook Inlet. Brief snow showers are
possible across Anchorage and the Matanuska Valley early Sunday
morning as this low weakens. Mostly cloudy skies and high
temperatures near freezing are expected Sunday. Snow showers will
remain possible near higher terrain.

A deep low and its associated front will track into the western
Gulf late Sunday evening. Strong easterly winds and periods of
heavy rain are expected in Kodiak City through Monday morning.
Snow may potentially mix with rain in the associated northerly
winds on the backside of the low. However, given both relatively
warm air and sea surface temperatures, any accumulation would be
minimal. As the front quickly approaches the coast early Monday
morning, snow is expected across much of the southern Kenai
Peninsula and western Prince William Sound. Minimal accumulations
are likely before precipitation changes to a mix or all rain
through the day Monday. One notable exception will be Turnagain
Pass where all snow is expected and gusty easterly winds may
reduce visibility during the early morning hours. The low will
weaken and depart to the east by Tuesday, yielding more benign
conditions as a ridge builds in its wake.

&&

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

Weather is quiet save for some lingering cloud cover and showers
present from a decaying lower pressure to the southeast near
Homer, AK. This will change for the AKPEN and Bristol Bay tomorrow
evening. The low pressure system we have been forecasting is now
skirting the south side of the Aleutians and will arrive on the
south side of the AKPEN tomorrow night. Our model guidance for
this low has come into better agreement today, so we have
increasing confidence in the forecast for this system. We are
expecting 2-4 inches of snow for Bristol Bay and gusty winds with
this system. Temperatures should remain warm enough to keep snow
wet and heavy enough from being blow around. Gusty winds on the
backside of the low will produce storm force gusts through passes
on the AKPEN. This system exits late Monday and Tuesday looks
quiet for Southwest AK.

&&

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

The Bering Sea and Aleutians are quiet to start this evening's
forecast, with just some westerly flow and cold air associate
cumulus clouds. This however will soon change with two lows moving
into the Bering over the next few days. The first low is now
visible on satellite moving towards the Aleutians. This low will
move northeast and impact the Eastern Aleutians tomorrow night,
bringing rain, snow and gusty northerly winds behind it.

The second system is a low moving into the Bering from Kamchatka
on Monday morning. It's front will be strong enough to have storm
force winds as it enters the Western Bering. It will weaken as it
moves across the Bering through Tuesday, but will stay strong
enough to maintain storm winds until it reaches the Central
Aleutians. These winds will be southerly, meaning strong warm
advection will be in place ahead of the front, which will warm
temperatures and shift precipitation to rain for the Bering.

&&

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

Gulf of Alaska:

Good confidence with overall pattern but some uncertainty remains
in the details during the 3-5 day timeframe. Gales decrease to
small crafts by Tuesday afternoon as the low departs into the
southeastern Gulf and high pressure briefly moves over the area.
the next front enters the Gulf Wednesday with Gales likely. A low may
form along this front Wednesday near the Shelikof Strait but low
confidence on the timing and track of this low. This front will
weaken Thursday morning as it moves inland.

Bering Sea:

Fairly good confidence as a front with high end Gales moves across
the central and eastern Bering Tuesday. This front weakens as it moves
into Southwest Alaska Wednesday morning. Late Tuesday a low may
develop along the front near the eastern Aleutians and move into
the eastern Bering or Bristol Bay region. However low confidence
in track and strength as models are all over the place. Another
low with at least Gales will move towards the western Aleutians by
Thursday afternoon, but lower confidence with strength and track
of this low. It is certain that an active pattern will continue
through Thursday across the Bering.

&&

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

A highly amplified pattern to start the period will transition to
a more zonal like pattern across the Bering and Gulf by Thursday
morning with a series of lows/fronts riding west to east along
the upper level jet near the Aleutians and tracking into Southwest
and Southcentral with increasing chances of snow through the
period.

Wednesday a strong front extending from Southwest Alaska and into
the Gulf will move into Southcentral late Wednesday into Thursday
and weaken. This front will produce a large area of rain and snow
for Southcentral. A triple point low may form along the front
near Shelikof Straight and track into Cook Inlet late Wednesday,
however some uncertainty with track and strength of this low. A
weaker low is expected to move across the Gulf Thursday and Friday
with minimal impacts. Another strong low pressure system will
moves into the Bering and Aleutians with an accompanying front
moving south of the Aleutians and into the Gulf on late Friday
into Saturday. However lots of uncertainty on track of this
system. It does look certain that an active pattern will continue
through Saturday for much of the forecast area.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE 119 136 137 139 140 150 160-172 174 177 178 180
		 STORM 120 130-132 138 155
FIRE WEATHER...NONE.

&&

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

The office that day

Everything else NWS Anchorage, AK issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Nov 21, 3:23 PM AKSTStorm WarningAFC48 hr
Nov 21, 3:44 PM AKSTGale WarningAFC12 hr
Nov 21, 3:50 PM AKSTGale WarningAFC48 hr
Nov 21, 3:50 PM AKSTSmall Craft AdvisoryAFC24 hr
Nov 21, 3:50 PM AKSTStorm WarningAFC12 hr
Nov 21, 3:59 PM AKSTGale WarningAFC24 hr
Nov 21, 3:59 PM AKSTSmall Craft AdvisoryAFC3 days
Nov 21, 3:59 PM AKSTStorm WarningAFC60 hr
Nov 22, 4:01 AM AKSTGale WarningAFC36 hr
Nov 22, 4:01 AM AKSTHurricane Force Wind WarningAFC36 hr
Nov 22, 4:01 AM AKSTSmall Craft AdvisoryAFC59 hr
Nov 22, 4:01 AM AKSTStorm WarningAFC36 hr
Nov 22, 4:04 AM AKSTGale WarningAFC12 hr
Nov 22, 4:04 AM AKSTStorm WarningAFC48 hr
Nov 22, 4:08 AM AKSTGale WarningAFC59 hr
Nov 22, 4:08 AM AKSTHurricane Force Wind WarningAFC36 hr
Nov 22, 4:08 AM AKSTStorm WarningAFC59 hr
Nov 22, 4:39 AM AKSTWinter Weather AdvisoryAFC28 hr

Nearby

Storm Warnings in Alaska, 2020Every storm warning in 2020

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text.