Heavy Freezing Spray Warning 162, NWS Anchorage, AK

476 
FZAK62 PAFC 290103
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
403 PM AKST Sun Nov 28 2021

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.

PKZ499-291400-
403 PM AKST Sun Nov 28 2021
.SYNOPSIS FOR CENTRAL BERING SEA...

A complex 955 mb low at 51N 167W moves to 55N 155W at 967 mb Mon 
afternoon and then moves into the Gulf of Alaska Tue Morning. 
Another North Pacific low moves to 55N 175E at 998 mb by Tue 
afternoon.

$$

PKZ411-291400-
Bering Sea Offshore West of 180 and East of the International
Dateline-
403 PM AKST Sun Nov 28 2021

...GALE WARNING TONIGHT...

.TONIGHT...NE wind 20 to 35 kt. Seas 13 to 21 ft. Freezing spray.
.MON...NE wind 10 to 25 kt. Seas 9 to 14 ft.
.MON NIGHT...SW wind up to 20 kt becoming S 15 to 30 kt after
midnight. Seas 6 to 11 ft. Freezing spray. Snow.
.TUE...S wind 20 to 35 kt. Seas 7 to 12 ft.
.TUE NIGHT...W wind 35 to 50 kt. Seas 12 to 20 ft.
.WED...W wind 30 to 45 kt. Seas 11 to 19 ft.
.THU...S wind 30 to 45 kt. Seas 13 to 28 ft.
.FRI...SW wind 25 to 40 kt. Seas 17 to 27 ft.

$$

PKZ412-291400-
Bering Sea Offshore 171W to 180 and North of 56N-
403 PM AKST Sun Nov 28 2021

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

.TONIGHT...NE wind 20 to 35 kt. Seas 9 to 16 ft. Heavy freezing 
spray.
.MON...N wind 15 to 30 kt. Seas 8 to 13 ft. Heavy freezing spray.
.MON NIGHT...N wind 10 to 25 kt. Seas 6 to 11 ft. Heavy freezing 
spray.
.TUE...SW wind 10 to 25 kt. Seas 5 to 10 ft.
.TUE NIGHT...SE wind 15 to 30 kt. Seas 5 to 10 ft.
.WED...SW wind 10 to 25 kt. Seas 7 to 12 ft.
.THU...S wind 25 to 40 kt. Seas 11 to 19 ft.
.FRI...SW wind 35 kt. Seas 19 to 25 ft.

$$

PKZ413-291400-
Bering Sea Offshore 171W to 180 and South of 56N-
403 PM AKST Sun Nov 28 2021

...STORM WARNING TONIGHT...

.TONIGHT...NE wind 35 to 50 kt diminishing to 30 to 40 kt after
midnight. Seas 17 to 23 ft. Freezing spray.
.MON...N wind 25 to 35 kt diminishing to 15 to 30 kt in the
afternoon. Seas 12 to 19 ft. Freezing spray. Snow showers.
.MON NIGHT...NW wind 15 to 30 kt. Seas 9 to 14 ft. Freezing spray.
.TUE...SW wind 15 to 30 kt. Seas 7 to 11 ft.
.TUE NIGHT...S wind 15 to 30 kt. Seas 7 to 12 ft.
.WED...N wind 35 to 50 kt. Seas 10 to 18 ft.
.THU...S wind 25 to 40 kt. Seas 10 to 18 ft.
.FRI...SW wind 35 kt. Seas 17 to 24 ft.

$$

PKZ414-291400-
Bering Sea Offshore East of 171W-
403 PM AKST Sun Nov 28 2021

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

.TONIGHT...NE wind 30 to 45 kt. Seas 9 to 17 ft. Heavy freezing
spray. Snow.
.MON...N wind 25 to 40 kt. Seas 10 to 18 ft. Heavy freezing spray.
Snow showers.
.MON NIGHT...N wind 25 to 35 kt. Seas 10 to 15 ft. Heavy freezing
spray. Widespread snow showers.
.TUE...NW wind 20 to 35 kt. Seas 9 to 15 ft.
.TUE NIGHT...NW wind 25 to 40 kt. Seas 9 to 14 ft.
.WED...N wind 10 to 25 kt. Seas 5 to 10 ft.
.THU...SW wind 15 to 30 kt. Seas 5 to 9 ft.
.FRI...SW wind 20 to 30 kt. Seas 11 to 18 ft.

$$

118 
FZAK62 PAFC 291315
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
415 AM AKST Mon Nov 29 2021

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.

PKZ499-300145-
415 AM AKST Mon Nov 29 2021
.SYNOPSIS FOR CENTRAL BERING SEA...

A complex 963 mb low at 52N 160W moves to 55N 153W at 969 mb Mon
afternoon. The low continues into the Gulf of Alaska Mon evening.
Another 998 mb low at 55N 168E moves to 55N 177W at 1003 mb Tue
night.

$$

PKZ411-300145-
Bering Sea Offshore West of 180 and East of the International
Dateline-
415 AM AKST Mon Nov 29 2021

...GALE WARNING TUESDAY...

.TODAY...NE wind 10 to 25 kt diminishing to up to 15 kt in the
afternoon. Seas 9 to 14 ft.
.TONIGHT...S wind 15 to 30 kt. Seas 6 to 11 ft. Snow.
.TUE...S wind 15 to 30 kt increasing to 25 to 40 kt in the
afternoon. Seas 6 to 11 ft. Snow and rain.
.TUE NIGHT...NW wind 35 to 50 kt. Seas 11 to 19 ft.
.WED...W wind 30 to 45 kt. Seas 11 to 19 ft.
.THU...S wind 30 to 45 kt. Seas 13 to 21 ft.
.FRI...SW wind 25 to 35 kt. Seas 15 to 26 ft.

$$

PKZ412-300145-
Bering Sea Offshore 171W to 180 and North of 56N-
415 AM AKST Mon Nov 29 2021

.TODAY...N wind 15 to 25 kt. Seas 7 to 12 ft. Freezing spray.
.TONIGHT...N wind 10 to 25 kt. Seas 5 to 10 ft. Freezing spray.
.TUE...NW wind 10 to 25 kt. Seas 4 to 9 ft. Freezing spray.
.TUE NIGHT...SE wind 15 to 30 kt. Seas 5 to 10 ft.
.WED...W wind 10 to 25 kt. Seas 7 to 12 ft.
.THU...S wind 30 to 45 kt. Seas 11 to 19 ft.
.FRI...SW wind 35 kt. Seas 18 to 24 ft.

$$

PKZ413-300145-
Bering Sea Offshore 171W to 180 and South of 56N-
415 AM AKST Mon Nov 29 2021

.TODAY...N wind 20 to 30 kt. Seas 11 to 17 ft. Freezing spray.
Snow showers.
.TONIGHT...NW wind 10 to 25 kt. Seas 8 to 13 ft. Freezing spray.
.TUE...SW wind 15 to 30 kt. Seas 6 to 10 ft. Freezing spray.
.TUE NIGHT...SW wind 30 to 45 kt. Seas 9 to 17 ft.
.WED...NW wind 35 to 50 kt. Seas 10 to 18 ft.
.THU...S wind 25 to 40 kt. Seas 9 to 17 ft.
.FRI...SW wind 25 to 35 kt. Seas 16 to 21 ft.

$$

PKZ414-300145-
Bering Sea Offshore East of 171W-
415 AM AKST Mon Nov 29 2021

...GALE WARNING THROUGH TUESDAY...
...HEAVY FREEZING SPRAY WARNING THROUGH TUESDAY...

.TODAY...N wind 25 to 35 kt. Seas 9 to 14 ft.
Heavy freezing spray. Snow showers.
.TONIGHT...N wind 25 to 35 kt. Seas 9 to 13 ft.
Heavy freezing spray. Widespread snow showers.
.TUE...NW wind 25 to 35 kt. Seas 9 to 14 ft. Heavy freezing spray.
.TUE NIGHT...NW wind 20 to 35 kt. Seas 8 to 13 ft.
.WED...NW wind 10 to 25 kt. Seas 5 to 10 ft.
.THU...SW wind 15 to 30 kt. Seas 5 to 9 ft.
.FRI...SW wind 20 to 30 kt. Seas 9 to 17 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
516 PM AKST Sat Nov 27 2021

.ANALYSIS AND UPPER LEVELS...

A large upper level low remains centered directly over most of the
AK mainland aloft, with Arctic high pressure and frigid temperatures
anchored in place closer to the surface. As has been the case for
the past few days, the coldest temperatures as low as -20 to -30F
(and even -40F earlier this morning) reside over Southwest Alaska,
with the most extremely cold air gripping the Middle Kuskokwim
Valley. Temperatures are warmer, but still well below climatological
norms over Southcentral, with mainly teens to single digits below
0F observed for interior spots throughout today. Over the
northern Gulf, a mesoscale surface low continues to meander in
place just to the west of Middleton Island. The low coupled with
marine layer instability also is continuing to set off a myriad of
convective snow showers visible on the Middleton Island radar.
Most of the shower activity has pulled away from areas east of
Prince William Sound (including Cordova) for now, with sporadic
snow showers still making it onshore to the west near Portage and
Whittier. Cold drainage/gap winds in this vicinity have continued
to blow around the powdery snow and reduce visibilities. Aside
from a stratus deck and associated snow flurries in the Y-K Delta,
clear and cold conditions persist for the remainder of the
southern mainland.

In the west, sensible conditions are overall much the same for
the eastern Bering/Aleutians, with cold air generally below
freezing spreading out anticyclonically from surface high
pressure. A few snow showers are still reaching the southern
Alaska Peninsula now and then, though they have become less
frequent and intense compared to the past couple days. Farther
west, a roughly 970 mb North Pacific low south of Shemya is
sending a gale force front into the western Bering/Aleutians.
A much warmer air mass is slowly advancing with the frontal
passage, with snow becoming mostly rain for the western Aleutians
as temperatures warm into the upper 30s.

&&

.MODEL DISCUSSION...

Models are, to put it lightly, not in the greatest agreement for
the most significant weather-maker to impact the outlook area over
the next several days, particularly beyond 24 to 36 hours from
initialization. The synoptic setup that models are struggling to
key in on is rather similar to what was occurring almost exactly a
week ago, with a low transiting areas just south of the Aleutians
and then up into the Gulf, running right up against a deeply
entrenched Arctic air mass over the AK mainland and Bering. One
important difference for this setup compared to one week ago is
that the scale of the low in question is much larger, with the
wind fields diameter spanning some 2,000 miles from west to east
across the Bering and North Pacific by tomorrow afternoon.

Even with the difference between the previous and upcoming
scenario mentioned above, the most important interaction models
are struggling with is still similar this time around. It remains
unclear how much the dense, Arctic air in place will resist being
displaced by the strong low pressure attempting to make northward
progress as it moves from south of the Aleutians on Sunday to the
Gulf on Monday and Tuesday. The American (GFS/NAM) models are
favoring a scenario where the cold air in place gives way more
easily, allowing the low to track farther northwest and close to
Kodiak Island and the Kenai Peninsula from Monday to Tuesday. The
Canadian and particularly the ECMWF models are essentially showing
the cold air win out for longer, and take the center farther east
across the Gulf before eventually recurving it as it weakens back
towards the Kenai Peninsula and Prince William Sound on Tuesday
afternoon. The most important difference for these diverging
scenarios will be the degree of impactful weather for areas
including the Alaska Peninsula, Kodiak Island, Prince William
Sound and Cook Inlet areas, with a more east track favoring lower
impacts to all of the above areas as well as a more eastward
shift for the stronger winds and blowing/falling snow possible
from Monday to Tuesday. This package will represent a middle
ground between a more west (mostly higher impacts) and east track,
with a lean closer to the ECMWF/Canadian. In addition, the GFS
has mostly been thrown out due to its apparent struggle with
its wild and inconsistent depiction of rapidly spinning up
multiple triple point lows.

&&

.AVIATION...
PANC...VFR conditions and light winds will persist. A low end VFR
ceiling could develop as a weak short-wave rotates through Sunday
afternoon, but confidence is low.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 to 2: Tonight
through Monday)...

A mesolow near Montague Island will continue to bring snow
showers to the Prince William Sound region and north Gulf coast
through Monday. As the mesolow moves eastward across the Gulf and
high pressure persists over land, the resulting pressure gradient
will drive stronger outflow winds through Kamishak Bay,
Resurrection Bay, and the Copper River Delta into Monday evening.
Upper level forcing will favor the strongest gap winds across the
western Gulf coastal waters, a with a series of short-waves
tracking from Southwest Alaska into the Gulf and driving the
deep Arctic air in place over Southwest through the gaps. These
winds will cross southern Cook Inlet into the outer portion of
Kachemak Bay. Thus, expect a sharp gradient of wind and waves as
you head up Kachemak Bay.

Beginning Sunday evening, a complex low south of the AKPEN
moves towards the Gulf. Much uncertainty remains with how the
complex low will evolve, where it will move, and where triple
point lows may form. For now, the low looks to track just south
of Kodiak by Monday afternoon. Its associated front will bring
gale-force winds throughout the Gulf and potential winter storm
conditions to Kodiak. Significant snowfall is possible on Kodiak
Island from late Sunday night to Monday morning before warmer air
likely causes a transition to rain. Uncertainty regarding the
timing of the transition could result in lesser or greater snow
amounts. There will also be quite a bit of wind, so blowing snow
will likely be an issue, especially early Sunday night before
temperatures begin to warm. While the forecast track of the low
close to Kodiak will result in stronger winds and blowing
snow/visibility concerns, the low could also remain further east.
In that scenario, precipitation may remain all snow and winds will
be lighter. The forecast for Kodiak will continue to be refined
with subsequent forecast packages. Beyond Kodiak, areas of
moderate to heavy snow will occur along the eastern Kenai
Peninsula and in Prince William Sound on Monday as the low and
its front move northward. Gale-force winds are likely along the
north Gulf coast with the formation of a barrier jet.

&&

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

A general troughing pattern extending from the Alaska mainland to
the eastern Bering Sea will remain in place for the weekend and
eject weak shortwaves with minimal impact expected. A persistent
northerly flow will help maintain a cold airmass with temperatures
still well below zero at least through Sunday night. A low south
of AKPEN will help draw moisture northwestward and light snow into
portions of the Y-K Delta, Bristol Bay, and the Lower Kuskokwim
Valley beginning Monday and continuing through Tuesday.

&&

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

A broad frontal boundary extending from a strong low pressure
system south of Shemya will continue to dominate the forecast
area over the next couple of days. Meanwhile, the front will
work in concert with another low developing south of Nikolski on
Sunday morning. In addition to rain and snow mix, high end gales
to low end storm force winds and elevated seas will spread across
the Aleutians, Bering Sea, and AKPEN through Monday evening. A
Winter Storm Watch has been updated for the Eastern Aleutians for
blizzard conditions remaining possible starting early Sunday
morning into Monday morning. Additionally, the latest operational
model runs are still not in agreement yet with the exact track
and position of the complex low as it migrates south of the
Aleutians and into the Gulf. Suffice to say that an active weather
pattern will persist through early next week.

&&

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

Gulf of Alaska: A complex area of low pressure will move from the
western Gulf to the northern Gulf for Tuesday. There is a great
deal of uncertainty in the track of any feature that enters the
Gulf through mid-week. However, it is looking more likely that any
gales or elevated seas earlier in the week will be diminishing by
Tuesday. Increasing westerly gale-force winds along with seas 10
to 15 feet are possible from the Barren Islands south to Kodiak
Island Wednesday and Thursday.

Bering Sea/Southwest: Northerly gales and elevated seas will
persist across the eastern half of the Bering and Aleutians
storm-force gusts are also possible across the eastern Aleutians
through Wednesday morning. Heavy freezing spray is also likely
during this time. A storm-force low will move from the western
Bering Tuesday morning to the eastern Aleutians Wednesday evening.
Southerly gales develop along a front over the western Bering by
Thursday.

&&

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

The longwave upper-level trough that has been the dominant weather
feature across the state of recent will re-establish itself by
mid-week, as a strong surface low and associated upper-level
shortwave move from the eastern Aleutians to the Gulf of Alaska.
The movement of these features, along with a developing upper-
level ridge upstream, will enhance the northerly flow, allowing
another round of arctic air to drop south. This arctic airmass
will spill into Southwest Alaska for Wednesday with snow showers
persisting across the AKPen and windward side of the Alaska Range.
The shortwave associated with this cold airmass will then track
east over Southcentral for Thursday. This feature will interact
with an area of weak low pressure in the northern Gulf, helping to
potentially draw enough moisture northward for areas of light
snow over parts of interior Southcentral.

Also by Thursday, guidance is indicating development of a strong
Kamchatka low that looks to lift into eastern Russia. There is
increasing confidence that this feature will drive a warm front
across the Bering as the core of the arctic airmass over the state
shifts east. This system may be the catalyst in changing the
overall upper-level pattern as it becomes more progressive with a
westerly steering flow. The front drives to the west coast of the
state by Friday as it begins to occlude. Nonetheless, there may
be some precipitation type concerns around the AKPen and Bristol
Bay as warmer air advects northward. Both the GFS and EC then show
the potential for a triple point low to form in the western Gulf
as the front moves to the interior of the state. This new low
would likely help draw moisture northward as the front weakens and
its associated shortwave moves east, bringing the potential for
light snow from the Kuskokwim Valley east to the Copper River
Basin through the day Saturday.

&&
.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Storm Watch 185.
MARINE...Storm Warning 155 170 172 173 174 175.
         Gale Warning 130 131 132 138 139 150 160 165 171 176 177
                      178 179 180.
         Heavy Freezing Spray Warning 121 127 128 129 130 131 136
                                      137 138 139 140 141 150 160
                                      165 179 180 181 185.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...AS
SOUTHCENTRAL ALASKA...KC
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MF
MARINE/LONG TERM...TM

SPECIAL WEATHER STATEMENT
National Weather Service ANCHORAGE AK
1118 PM AKST Sat Nov 27 2021

AKZ171-281400-
Kodiak Island-
Including the city of Kodiak City
1118 PM AKST Sat Nov 27 2021

...Another Potential Snow Set-Up for Kodiak Island...

A strong North Pacific low will take shape late Sunday south of
Sand Point. This system will push a front towards Kodiak Island
by early Monday morning. As is often the case with storms from
this direction, the forecast models are struggling to lock onto
the storm track. Also, due to warm sea surface temperatures
(~40F), there will be a fine line between cold temperatures and
snow versus 35F and rain. This system will also bring strong winds
across the Gulf with the potential for gusts to approximately 50
mph.

IF the temperatures can remain cold enough to keep the
precipitation as snow, the result would be moderate to heavy
snowfall rates with the potential for significant accumulation on
the order of 6 to 10 inches. The combination of winds and falling
(driving) snow could make for an extended period of reduced
visibility.

Due to the large amount of uncertainty with the exact track of the
storm, forecast confidence is low at this time. However, stay
advised of the forecast as we head through the weekend and refine
the details.