Gale Warning 587, NWS Anchorage, AK

093 
FZAK61 PAFC 240025
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
325 PM AKST Sat Nov 23 2019

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.

PKZ399-241345-
325 PM AKST Sat Nov 23 2019
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 990 mb low at 61N 146W loops over the Northern Gulf to 58N 139W
at 1013 mb for Mon afternoon. Its front wraps over the North Gulf
Coast pushing inland by Sun afternoon. Weak high pressure enters
the Western Gulf for Mon afternoon.

$$

PKZ351-241345-
Gulf of Alaska Offshore North of 57N and West of 144W-
325 PM AKST Sat Nov 23 2019

...GALE WARNING SUNDAY NIGHT...

.TONIGHT...W wind 20 to 30 kt. Seas 12 to 16 ft.
.SUN...W wind 20 to 30 kt. Seas 12 to 15 ft.
.SUN NIGHT...W wind 25 to 35 kt. Seas 13 to 18 ft.
.MON...NW wind 20 to 35 kt. Seas 11 to 17 ft.
.MON NIGHT...NW wind 15 to 30 kt. Seas 8 to 13 ft.
.TUE THROUGH WED...SW wind 10 to 25 kt. Seas 5 to 9 ft.
.THU...SW wind 25 kt. Seas 9 to 14 ft.

$$

PKZ352-241345-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
325 PM AKST Sat Nov 23 2019

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

.TONIGHT...W wind 30 kt. Seas 14 to 18 ft.
.SUN...W wind 25 to 35 kt. Seas 17 ft. Rain showers.
.SUN NIGHT...W wind 25 to 35 kt. Seas 13 to 19 ft.
.MON...NW wind 20 to 30 kt. Seas 9 to 17 ft.
.MON NIGHT...NW wind 20 to 30 kt. Seas 9 to 14 ft.
.TUE THROUGH WED...SW wind 20 to 30 kt. Seas 6 to 11 ft.
.THU...S wind 25 kt. Seas 10 to 17 ft.

$$

331 
FZAK61 PAFC 241237
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
337 AM AKST Sun Nov 24 2019

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-
337 AM AKST Sun Nov 24 2019
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...
A 998 mb low at 60N 147W moves to 59N 145W at 1010 mb Mon afternoon.
Weak high pressure enters the Western Gulf Mon afternoon.

$$

PKZ351-250130-
Gulf of Alaska Offshore North of 57N and West of 144W-
337 AM AKST Sun Nov 24 2019

...GALE WARNING TONIGHT AND MONDAY...

.TODAY...W wind 20 to 30 kt. Seas 12 to 15 ft. Rain showers.
.TONIGHT...W wind 25 to 35 kt. Seas 13 to 18 ft.
.MON...NW wind 20 to 35 kt. Seas 10 to 17 ft.
.MON NIGHT...NW wind 15 to 30 kt. Seas 8 to 13 ft.
.TUE...SW wind 10 to 25 kt. Seas 4 to 8 ft.
.WED THROUGH THU...SW wind 10 to 25 kt. Seas 9 to 14 ft.

$$

PKZ352-250130-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
337 AM AKST Sun Nov 24 2019

...GALE WARNING THROUGH TONIGHT...

.TODAY...W wind 25 to 35 kt. Seas 17 ft. Widespread rain showers.
.TONIGHT...W wind 25 to 35 kt. Seas 13 to 19 ft.
.MON...NW wind 20 to 30 kt. Seas 9 to 17 ft.
.MON NIGHT...NW wind 15 to 30 kt. Seas 9 to 14 ft.
.TUE THROUGH WED...S wind 15 to 30 kt. Seas 8 to 13 ft.
.THU...S wind 10 to 20 kt. Seas 12 to 18 ft.

$$

385 
FZAK61 PAFC 250034
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
334 PM AKST Sun Nov 24 2019

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.

PKZ399-251330-
334 PM AKST Sun Nov 24 2019
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 1007 mb low at 60N 145W dissipates as it exits the Southeastern
Gulf Tue afternoon. High pressure slides to the Central Gulf for
Tue afternoon.

$$

PKZ351-251330-
Gulf of Alaska Offshore North of 57N and West of 144W-
334 PM AKST Sun Nov 24 2019

...GALE WARNING THROUGH MONDAY...

.TONIGHT...W wind 25 to 35 kt. Seas 13 to 18 ft.
.MON...NW wind 20 to 35 kt. Seas 11 to 17 ft.
.MON NIGHT...NW wind 15 to 30 kt. Seas 8 to 13 ft.
.TUE...W wind 10 to 20 kt. Seas 5 to 8 ft.
.TUE NIGHT...SW wind 10 to 25 kt. Seas 5 to 10 ft.
.WED THROUGH FRI...N wind 10 to 25 kt. Seas 9 to 15 ft.

$$

PKZ352-251330-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
334 PM AKST Sun Nov 24 2019

...GALE WARNING TONIGHT...

.TONIGHT...W wind 35 kt. Seas 13 to 19 ft.
.MON...NW wind 20 to 30 kt. Seas 9 to 16 ft.
.MON NIGHT...NW wind 15 to 30 kt. Seas 9 to 14 ft.
.TUE...W wind 10 to 25 kt. Seas 6 to 11 ft.
.TUE NIGHT...S wind 15 to 30 kt. Seas 7 to 12 ft.
.WED THROUGH FRI...N wind 15 to 30 kt. Seas 10 to 18 ft.

$$

540 
FZAK61 PAFC 251227
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
327 AM AKST Mon Nov 25 2019

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.

PKZ399-260130-
327 AM AKST Mon Nov 25 2019
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 1015 mb low at 60N 144W dissipates as it exits the Southeastern
Gulf Mon night. High pressure slides to the Central Gulf Tue 
afternoon.

$$

PKZ351-260130-
Gulf of Alaska Offshore North of 57N and West of 144W-
327 AM AKST Mon Nov 25 2019

...GALE WARNING TODAY...

.TODAY...NW wind 20 to 35 kt. Seas 11 to 17 ft.
.TONIGHT...NW wind 15 to 30 kt. Seas 8 to 13 ft.
.TUE...W wind 10 to 20 kt. Seas 5 to 8 ft.
.TUE NIGHT...SW wind up to 20 kt. Seas 4 to 8 ft.
.WED THROUGH THU...SW wind 15 to 30 kt. Seas 9 to 14 ft.
.FRI...N wind up to 15 kt. Seas 9 to 15 ft.

$$

PKZ352-260130-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
327 AM AKST Mon Nov 25 2019

.TODAY...NW wind 20 to 30 kt. Seas 10 to 17 ft.
.TONIGHT...NW wind 15 to 30 kt. Seas 8 to 13 ft.
.TUE...NW wind 10 to 25 kt becoming W in the afternoon. Seas 5 to
10 ft.
.TUE NIGHT...S wind 15 to 30 kt. Seas 5 to 10 ft.
.WED...S wind 15 to 30 kt. Seas 8 to 13 ft.
.THU THROUGH FRI...N wind 10 to 25 kt. Seas 10 to 18 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
418 PM AKST Fri Nov 22 2019

.ANALYSIS AND UPPER LEVELS...
Broad cyclonic flow with embedded waves continues across much of
the mainland and Gulf of Alaska. Unstable conditions with the cold
upper trough is producing widespread rain showers with isolated
to scattered thunderstorms across the Gulf and coasts. Mixed
showers were evident across Southcentral. With cooler air over the
Southwest Mainland showers were predominately snow though there
were a few rain showers over Bristol Bay associated with a wedge
of warmer air. The presence of widespread open cell cumulus clouds
and showers across the Bering Sea is indicative of cold advection
over the relatively warmer water surface. Also, gusty winds have
been reported in showers along the Aleutians.

&&

.MODEL DISCUSSION...
Models overall are in good agreement with the synoptic features
in the short term. They still struggle some with the finer
details, such as, the location of shower activity.

&&

.AVIATION...
PANC...An upper trough moving north tonight will bring periods of
MVFR ceilings and/or visibilities with showers through Saturday
morning.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
A surface low making its way up Cook Inlet this afternoon will
continue to produce areas of showers along western Kenai
Peninsula, Anchorage Bowl, and Mat-Su valleys through Saturday.
Showers will also continue across Prince William Sound along a
surface trough. Colder air is wrapping around the aforementioned
low, so as it and its associated upper-level trough lift north
overnight, rain showers will mix with and changeover to snow
showers. The southwesterly flow both at the surface and aloft will
keep the more persistent showers over the Mat-Su valleys where
light snow accumulations are possible. For Anchorage and portions
of the Kenai Peninsula, the majority of the precipitation will be
exiting the region by the time the coldest of air works in. Thus,
little to no snow accumulation is expected, although an inch or so
along the Anchorage Hillside is not out of the question.

Just as the shower activity begins to diminish for all but the
higher terrain and passes late Saturday, a second upper-level
wave will move across Southcentral. This will usher in even
colder air and help enhance snow shower activity across the
Chugach and Talkeetna Mountains as well as portions of the Susitna
Valley. This feature will also signal the start of a significant
cooling trend that will be further enhanced by the exit of the
main upper-level low late Sunday and the development of northerly
flow. By the end of the weekend, the main weather focus will be
the downward trend in temperatures and the development of gusty
outflow winds across coastal Southcentral.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 3)...
Light snow showers are still lingering in southwest Alaska on the
backside of the last low pressure system that pushed through the
area a couple days ago. A chance of precipitation will remain
until the weather clears briefly on Sunday. Expect a drop in
temperatures with this clearing. On Monday, a fast moving frontal
system will push directly into southwest Alaska. It will bring
gusty winds, precipitation, and warming temperatures. With it
being a few days away, we are still honing the forecast for this
system. Right now, it looks like blowing snow and heavy snow ahead
of warming temperatures is likely, then a quick warm up as the
system pushes inland. There is still too much uncertainty to know
if blizzard conditions will be possible. With that, parameters
like precipitation type are still coming together that will make
or break the forecast, so stay tuned to forecast updates as we
will know more in the next day or so.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 through 3)...
The Bering Sea starts out quiet with northerly flow behind a low
pressure to the east over mainland Alaska. As northerly flow does
this time of year, snow showers are embedded in this cold air
push. This will all change Sunday into Monday with a change in the
weather pattern. First on Sunday a shortwave ridge will move
through Bering. Following quickly behind it will be the first of
two low pressure systems that will switch winds to southwesterly
direction. The first low will move through Sunday and bring gale
force winds with it for much of the Bering. A second, more
powerful low will move into the Bering Monday. This low will have
widespread gales with a swath of storm force winds in the Central
Bering. This low will continue to push east through the Bering
into Tuesday.

&&

.MARINE (Days 3 through 5)...
Areas of west to northwesterly Gales will are likely in the
western Gulf and through the Barren Islands Sunday night and
Monday with localized strong outflow winds near terrain gaps along
the northern Gulf coast. Offshore flow will diminish Monday night
through Tuesday with wind remaining at Small Craft Advisory
levels or less in the Gulf and adjacent coastal waters through
Wednesday afternoon. A very strong front pushing across the
Bering will bring widespread Gale to Storm force south to
southwesterly winds Sunday night through Tuesday. Overall, winds
will diminish Tuesday night through Wednesday as ridging builds
into the western Bering with Gales limited to the waters near the
eastern Aleutians and Alaska Peninsula where a developing north
Pacific frontal wave will approach midweek.

&&

.LONG TERM FORECAST (Days 3 through 7)...
On Monday a cold upper level trough will be in place over
Southcentral Alaska with strong offshore flow persisting through
the day and then diminishing Monday night as upper level ridging
builds in from the west and the trough exits to the east. A front
in the eastern Bering will reach the Kuskokwim Delta coast midday
Monday and push inland over Southwest Alaska through Monday
evening. A second stronger and rather large frontal system
stretching across the Bering will catch up over the first and
spread additional heavier precipitation across Southwest Alaska
Monday night through Tuesday.

While there are some potential concerns for freezing rain to be
briefly mixed in with the snow expected from the first front,
strong southwesterly flow aloft accompanying the warm advection
with the stronger second front should change precipitation near
the Southwest Alaska coast over to rain fairly quickly with snow
or a possible wintery mix lingering longer further inland. For
Southcentral Alaska, remnants of the first frontal system will
push up the western side of the upper ridge on Tuesday bringing
good chances for snow with it to the Susitna Valley, Talkeetna
Mountains and Anchorage area Tuesday afternoon through Wednesday.

A north Pacific frontal wave interacting with the trailing
southern end of the cold front associated with the big Bering low
will spin up a new low south of the eastern Aleutians Tuesday
night and Wednesday. The associated warm front will reach the
Alaska Peninsula and Kodiak Island Wednesday morning and then push
over the Greater Bristol Bay area, western Gulf and Kenai
Peninsula Wednesday afternoon and evening. The front will continue
to the northeast, bringing warmer and moister air into
Southcentral Alaska Wednesday night creating significant forecast
challenges regarding how far north and inland the rain vs snow
line will push during a time period with heavy precipitation rates
over much of the area.

A colder upper level trough will push into Southwest Alaska
Wednesday night and Thursday, continuing east into Thursday night
and Friday. The strong cold air advection that it brings as well
as its interaction with all the warm, moist air entrained in the
frontal system ahead of it will bring the potential for a
significant snow event to Southcentral for the end of the week.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Gale Warning 150 165 185.
FIRE WEATHER...NONE.

&&

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