Gale Warning 773, NWS Anchorage, AK

897 
FZAK62 PAFC 102358
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
258 PM AKST Sat Dec 10 2022

Offshore Waters Forecast for the Bering Sea

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.

PKZ499-111515-
258 PM AKST Sat Dec 10 2022
.SYNOPSIS FOR CENTRAL BERING SEA...

A front will move through the central and eastern Bering Sea this
afternoon through Sunday morning. A 995 mb low will develop near
52N 176E Sunday afternoon and will move to 58N 174W at 988 mb
Monday afternoon.

$$

PKZ411-111515-
Bering Sea Offshore West of 180 and East of the International
Dateline-
258 PM AKST Sat Dec 10 2022

.TONIGHT...W wind 15 to 30 kt. Seas 9 to 16 ft.
.SUN...SW wind 10 to 20 kt. Seas 6 to 10 ft.
.SUN NIGHT...E wind 10 to 25 kt. Seas 4 to 7 ft. Snow and rain.
.MON...NW wind 15 to 30 kt. Seas 5 to 10 ft.
.MON NIGHT...W wind 15 to 30 kt. Seas 9 to 14 ft.
.TUE...W wind 20 to 30 kt. Seas 14 to 20 ft.
.WED...N wind 15 to 30 kt. Seas 9 to 14 ft.
.THU...SE wind 15 to 30 kt. Seas 9 to 17 ft.

$$

PKZ412-111515-
Bering Sea Offshore 171W to 180 and North of 56N-
258 PM AKST Sat Dec 10 2022

.TONIGHT...W wind 20 to 30 kt. Seas 12 to 17 ft.
.SUN...W wind 15 to 30 kt. Seas 9 to 16 ft.
.SUN NIGHT...SW wind up to 15 kt becoming SE 15 to 30 kt after 
midnight. Seas 6 to 11 ft.
.MON...E wind 15 to 30 kt. Seas 5 to 10 ft.
.MON NIGHT...NW wind 20 to 35 kt. Seas 9 to 14 ft.
.TUE THROUGH WED...NW wind 25 to 40 kt. Seas 8 to 16 ft.
.THU...NE wind 10 to 20 kt. Seas 6 to 11 ft.

$$

PKZ413-111515-
Bering Sea Offshore 171W to 180 and South of 56N-
258 PM AKST Sat Dec 10 2022

.TONIGHT...NW wind 20 kt. Seas 8 to 12 ft.
.SUN...W wind 10 to 25 kt. Seas 8 to 11 ft.
.SUN NIGHT...S wind 10 to 25 kt. Seas 6 to 10 ft. Snow and rain.
.MON...SW wind 20 to 35 kt. Seas 9 to 14 ft.
.MON NIGHT...W wind 20 to 35 kt. Seas 9 to 17 ft.
.TUE...NW wind 15 to 30 kt. Seas 9 to 14 ft.
.WED...NW wind 30 to 45 kt. Seas 11 to 19 ft.
.THU...SE wind up to 20 kt. Seas 9 to 16 ft.

$$

PKZ414-111515-
Bering Sea Offshore East of 171W-
258 PM AKST Sat Dec 10 2022

.TONIGHT...W wind 10 to 25 kt becoming 20 kt after midnight. Seas
9 to 14 ft.
.SUN...NW wind 25 kt. Seas 8 to 12 ft.
.SUN NIGHT...W wind 15 to 30 kt. Seas 7 to 11 ft.
.MON...S wind 20 to 35 kt. Seas 7 to 12 ft.
.MON NIGHT...SW wind 25 to 40 kt. Seas 11 to 19 ft.
.TUE...SW wind 25 to 40 kt. Seas 10 to 18 ft.
.WED...NE wind 15 to 30 kt. Seas 9 to 17 ft.
.THU...E wind 15 kt. Seas 9 to 14 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
620 PM AKST Fri Dec 9 2022

.ANALYSIS AND UPPER LEVELS...

An upper-level ridge continues to build in from the west as the
trough downstream moves over the Al-Can border. The northerly flow
between the two, combined with cold air advection and weaker waves
/ vorticity maxima sliding south in the northerly flow, are
allowing the strong offshore winds to persist through this
afternoon. Gusts are peaking between 35 and 45 mph for Seward,
Kodiak City, and Whittier with occasional gusts around 50 mph for
Valdez. Other than the strong wind gusts, conditions are generally
tranquil across the remainder of Southcentral, with clear skies
and cold temperatures.

Out west, some low stratus is lingering underneath the ridge,
leading to pockets of very light snow across portions of interior
Bristol Bay north to the Kuskokwim Valley. A front associated with
low over Attu is moving east across the Bering Sea this afternoon.
Rain and gusty southerly winds are occurring over the western half
of the Aleutians with this system.

&&

.MODEL DISCUSSION...

The latest operational model runs are in decent agreement with
the placement and intensity of synoptic scale features at both the
surface and in the upper levels. The frontal system over the
Bering Sea is still on track to produce snow and gusty southerly
winds across coastal Southwest Alaska for Saturday morning. There
is some difference both magnitude and eastern extent of warmer
air moving in behind the front. The difference with the warm air
advection will determine how far inland a rain/snow mix develops
in the wake of the front as the precipitation tapers off. As the
frontal system enters the western Gulf on Saturday, snow returns
across Southcentral for the weekend and continuing through early
next week. Models have trended back to a solution where the
shortwave moving from the North Pacific delays in strengthening
to a upper-level low, bringing the strongest vorticity advection
and lift farther north near the Kenai Peninsula. Models are also
back to trying to phase this wave with upper-level wave over the
northern Bering, negatively tilting the entire trough as it moves
to the northern Gulf. If this trend holds, it will likely result
in widespread significant snow across much of Southecentral.
There are differences in the placement of a deformation band along
the mid-level trough and the magnitude of southeasterly winds
ahead of a front. Stronger winds, as seen on the NAM runs, would
lend to a higher potential for downsloping initially along with
warmer temperatures and precipitation type issues along the
eastern Kenai Peninsula coast.

&&

.AVIATION...

PANC...VFR conditions and light winds will persist. Occasional
northeasterly gusts to around 15 kt are possible this afternoon.
Clouds and light snow are also possible by late Saturday
afternoon.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3: This
afternoon through Monday afternoon)...

High pressure continues to move eastward from the Bering
Sea/Southwest Alaska towards and eventually overhead for
Southcentral Alaska. Although today has been a beautiful day for
Southcentral, it has been cold with high temperatures ranging from
the negative single in Talkeetna to teens in Anchorage and the
Copper River Basin. As the ridge moves overhead, gusty gap winds
will begin to diminish.

The ridge flattens out and begins to move eastward during the day
Saturday and this reintroduces Southcentral to broad west-
southwesterly flow aloft as our next impactful system approaches
from the Southwest. Kodiak Island will be the first to see
precipitation Saturday afternoon in the form of snow. With a warm
air push from the southwest, Kodiak Island will turn to rain/snow
mix and eventually all rain as temperatures warm Saturday night.

Attention then turns to the rest of Southcentral as a period of
overrunning snow appears likely with light accumulations possible.
There could be a break in the precipitation Sunday morning for
the Western Kenai Peninsula, Mat-Su Valley, and Anchorage Bowl due
to cross-barrier flow from the southeast before precipitation
intensity really picks back up Sunday afternoon, through the
overnight, and lasting into the day on Monday. At this time,
snowfall amounts look to be significant and on the order of the
last event December 6-7. With that, we have issued Winter Storm
Watches for most of Southcentral. There is still uncertainty as
far as amounts go for coastal places like Homer, Seward, Whittier,
Cordova, and Portage Valley due to potential warmer air pushing in
from the coast. Please pay attention to future forecasts as finer
details on storm track, snowfall amounts, and timing get nailed
down.

&&

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

An occluded front continues to move across the Bering this front
is expected to reach the Kuskokwim Delta around midnight with
increasing winds. Wind gusts up to 60 mph are expected near the
coast with 40 to 45 mph gusts inland. These winds combined with
falling snow will create blowing snow reducing visibilities down
to a half mile. However, as the temperatures warm the threat of
blowing snow will end by late morning to around noon across the
area. This front will also bring light snow with 1 to 3 inches
expected through Saturday across the Kuskokwim Delta. The front
will weaken as it moves inland across Bristol Bay with winds
gusting up to 40 mph near the coast and weaker inland. Snowfall
across the Bristol Bay area will range from 3 to 6 inches mainly
north and west of King Salmon.

Our focus then turns to a potent low pressure system which will
bring another round of snow to Bristol and the middle Kuskokwim
valley. As it's parent shortwave strengthens colder air will
allow for a surface low to develop along a front moving near the
AKPen. As this low deepens areas of moderate to heavy snow will
develop over Bristol Bay and parts of the Kuskokwim valley west of
Crooked Creek Saturday evening through Monday morning with 8 to
14 inches of snow expected with localized higher amounts
expected. The snow is expected to come to an end by Monday
morning.

&&

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

A frontal system will continue to move across the Bering and
Aleutians through tonight with gales and pockets of storm force
winds. The AKPen will see light snow near the front changing to
rain tonight through Sunday morning. In the wake of the front
colder air will move southwards towards the Aleutians producing
areas of snow showers. Sunday afternoon a new low pressure system
moves into the western Aleutians. This low will move northwest
towards the northern Bering Sea while its associated front moves
eastward on Monday across the Bering. Gales are expected near this
low pressure system with another round of rain across the
Pribilofs and Aleutians for Sunday night into Monday.

&&

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

Latest model solutions for Tuesday continue to depict a weakening
area of low pressure along the northern Gulf of Alaska coast,
weak ridging skirting the Eastern Aleutians, and a second area of
low pressure lifting northward into the western Bering. Across
Southcentral this will help to see snow decrease across the region
and winds to also diminish. However, a quick moving air mass of
colder 850 mb temperatures moving through the Copper River Basin
may see outflow winds temporarily linger along the Gulf coast over
the first half of Tuesday. High pressure then builds over the
region with warmer temperatures through Thursday.

Out west, ensemble guidance and operational models want to bring
a strong Kamchatka upper low into the western Bering by the middle
of next week. While there are differences in the overall
intensity of the low, placement of the low between ensembles and
even operational models is in relatively good agreement. The
placement of the low will result in strong southerly warm air
advection ahead of the low, including the Eastern Aleutians and
Alaska Peninsula. So much so that Southwest Alaska could see
anomolous warm temperatures and the predominant precipitation type
as rain. Over the Bering, models signal the likelihood of gale to
storm force winds, both ahead and behind the low. The direction
of winds would remain out of the south ahead of the low, while out
of the north behind the low. Furthermore, significant cold air
advection on the backside of the low and across the western Bering
would favor an even higher wind threat.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Storm Watch: 101 111 121 125 131 141 145.
         Winter Weather Advisory 155 161.
MARINE...Storm Warning: 170.
         Gale Warning: 119 130 155 165 171-175 177-181 185.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...TM
SOUTHCENTRAL ALASKA...DAN
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...RC
LONG TERM...BL