Heavy Freezing Spray Warning 89, NWS Anchorage, AK

970 
FZAK62 PAFC 040048
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
348 PM AKST Wed Mar 3 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.

PKZ499-041400-
348 PM AKST Wed Mar 3 2021
.SYNOPSIS FOR CENTRAL BERING SEA...

A 963 mb North Kamchatka low moves to the East Siberian Sea coast
for Fri afternoon. Its front moves across the Aleutians and 
Bering into Western Alaska by Thu afternoon. A 972 mb North 
Kamchatka low Thu afternoon moves to 61N 176W at 992 mb through 
Fri afternoon.

$$

PKZ411-041400-
Bering Sea Offshore West of 180 and East of the International
Dateline-
348 PM AKST Wed Mar 3 2021

...STORM WARNING THURSDAY AND THURSDAY NIGHT...

.TONIGHT...W wind 30 to 45 kt. Seas 19 to 27 ft. Heavy freezing 
spray.
.THU...W wind 40 to 50 kt. Seas 25 to 30 ft. Freezing spray.
.THU NIGHT...W wind 40 to 50 kt diminishing to 30 to 45 kt after
midnight. Seas 25 to 34 ft. Heavy freezing spray north of 56N.
.FRI...SW wind 30 to 45 kt. Seas 15 to 27 ft.
.FRI NIGHT...SW wind 30 to 45 kt. Seas 16 to 24 ft.
.SAT...S wind 30 to 45 kt. Seas 17 to 26 ft.
.SUN THROUGH MON...SW wind 30 kt. Seas 9 to 16 ft.

$$

PKZ412-041400-
Bering Sea Offshore 171W to 180 and North of 56N-
348 PM AKST Wed Mar 3 2021

...STORM WARNING TONIGHT...

.TONIGHT...SW wind 35 to 50 kt. Seas 13 to 21 ft. Rain and snow.
.THU...W wind 35 to 45 kt. Seas 19 to 28 ft. Freezing spray.
.THU NIGHT...W wind 30 to 45 kt. Seas 24 to 34 ft. Freezing spray.
.FRI...W wind 30 to 45 kt. Seas 19 to 34 ft.
.FRI NIGHT...SW wind 25 to 40 kt. Seas 16 to 25 ft.
.SAT...SW wind 30 to 40 kt. Seas 17 to 23 ft.
.SUN THROUGH MON...SW wind 15 to 30 kt. Seas 12 to 20 ft.

$$

PKZ413-041400-
Bering Sea Offshore 171W to 180 and South of 56N-
348 PM AKST Wed Mar 3 2021

...STORM WARNING THURSDAY NIGHT...

.TONIGHT...SW wind 30 to 45 kt. Seas 13 to 21 ft. Rain with snow.
.THU...W wind 40 kt. Seas 19 to 27 ft.
.THU NIGHT...W wind 35 to 50 kt. Seas 25 to 33 ft.
.FRI...SW wind 30 to 45 kt. Seas 25 to 32 ft.
.FRI NIGHT...SW wind 30 to 40 kt. Seas 20 to 27 ft.
.SAT THROUGH MON...SW wind 20 to 35 kt. Seas 14 to 22 ft.

$$

PKZ414-041400-
Bering Sea Offshore East of 171W-
348 PM AKST Wed Mar 3 2021

...STORM WARNING TONIGHT...
...HEAVY FREEZING SPRAY WARNING THROUGH THURSDAY...

.TONIGHT...S wind 20 to 35 kt increasing to 35 to 50 kt after
midnight. Seas 7 to 12 ft. Heavy freezing spray. 
.THU...SW wind 30 to 45 kt becoming W in the afternoon. Seas 12 to
20 ft. Heavy freezing spray in the morning. 
.THU NIGHT...W wind 25 to 35 kt becoming SW 30 to 45 kt after
midnight. Seas 15 to 29 ft. Freezing spray.
.FRI...W wind 30 to 45 kt. Seas 18 to 31 ft.
.FRI NIGHT...W wind 25 to 40 kt. Seas 15 to 26 ft.
.SAT THROUGH SUN...S wind 20 to 35 kt. Seas 13 to 21 ft.
.MON...SW wind 10 to 25 kt. Seas 9 to 15 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
454 PM AKST Tue Mar 2 2021

.ANALYSIS AND UPPER LEVELS...

An amplified pattern is in place across the state as a deep upper
level trough over the mainland extends along an axis from the
North Slope southward toward the Gulf. Meanwhile over the
Bering, an upper level ridge is gradually building in from the
west. At the surface, a complex low is slowly moving southward,
with one center over the Kuskokwim Delta Coast. The second low
center is centered over the southern Alaska Peninsula and moving
south. Both of these features have brought snow and blowing snow
conditions to much of the central and eastern Bering, including
the Pribilofs, eastern Aleutians, southern Alaska Peninsula, and
also the Kuskokwim Delta Coast. Farther east, low level stratus in
place across Southcentral this morning is gradually dissipating as
a more northerly/offshore flow pattern sets ups.

&&

.MODEL DISCUSSION...

Models are generally in good agreement with the broad area of low
pressure over the eastern Bering. By late Wednesday into early
Thursday, model solutions are also in fair agreement with the
track of an incoming Kamchatka low over the western Bering. The
track of this low has been consistently advertised as moving
northward while the associated front pushes eastward across the
Bering with agreement on southerly high end gales to possibly
storm force winds. Meanwhile for Southcentral, models have been
keeping the residual low in place over the Gulf through the end of
the week, with its position remaining nearly stationary. By the
weekend, there are some discrepancies with the formation of a
triple point in the vicinity of Kodiak Island. Models are
advertising various solutions with the strength and track of this
low as it moves into the Gulf, and therefore confidence at this
time for the weekend remains low.

&&

.AVIATION...

PANC...Light northerly winds and VFR conditions are expected. Low
stratus and fog may develop over Cook Inlet and drift over the
terminal late this evening into early Wednesday morning.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 3: Today
through Friday afternoon)...

Scattered snow showers in the Copper River Basin will gradually
taper off this evening as offshore flow develops over the region.
Northerly winds will likewise persist across Southcentral leading
to mostly sunny skies and cooler temperatures. Winds through
terrain gaps will gradually increase through Wednesday. Gusts as
high as 55 mph are possible through Thompson Pass Wednesday night
into early Thursday morning brining the potential for periods of
blowing snow and reduced visibilities. Weaker flow across
Anchorage and the Mat-Su Wednesday and Thursday mornings could
lead to low stratus and/or patchy fog. Temperatures will be
slightly warmer where this would occur. Offshore flow will weaken
Thursday evening as a front approaches from the west. While there
remains some uncertainty, initial downsloping appears likely in
Anchorage and the Matanuska Valley. Snow will then develop on the
backside of the low as it begins to track southward in the Gulf by
late Friday. Significant accumulations are possible over the
eastern Kenai Peninsula as precipitation will linger there for
much of the day Friday.

&&

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

Snow and blowing snow continues across the Kuskokwim Delta this
evening. The heaviest snow and strongest winds are located along
the coastal section of the Kuskokwim Delta. There is a Blizzard
Warning in effect through this evening for the coastal Kuskokwim
Delta due to the combination of strong winds and ample amounts of
transportable snow (light fluffy snow that is prone to blow
around) causing visibility to be reduced to a quarter of a mile or
less at times. Winds should gradually ease later tonight which
will result in an improvement to visibility. The snow and blowing
snow will also continue across the AKPEN, though due to a lesser
amount of transportable snow visibility will be restricted to a
half mile at times. A Winter Weather Advisory remains in effect
for the Alaska Peninsula through early Wednesday morning. The
winds across the AKPEN will ease throughout Wednesday morning.
Wednesday will overall be a quiet weather day for Southwest Alaska
as dry offshore flow persists across the area. The next round of
active weather will be on Thursday as an occluded front (warm
occlusion) moves over Southwest Alaska. Precipitation type is
expected to mainly be snow, though forecast confidence is only
moderate at this time. Areas that will have the best chance of
rain mixing in are southern Bristol Bay and the AKPEN.

&&

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

An active weather pattern will continue across the
Bering/Aleutians over the next 3 days. Widespread gale force
winds will continue through the eastern Bering Sea this evening
and tonight. Storm force winds will continue in and around gaps
(i.e. Unimak Pass) along the AKPEN and eastern Aleutians that are
prone to funneling northwesterly winds. A Blizzard Warning remains
in effect for the Pribilof and eastern Aleutian Islands this
evening. A Winter Weather Advisory for Blowing Snow remains in
effect through early Wednesday morning for the AKPEN. Transient
high pressure that is currently over the western Bering/Aleutians
will gradually move eastward to over Bristol Bay by Wednesday
night and then into the Gulf by late Thursday morning. Another
front associated with the next low will move eastward across the
Bering/Aleutians from Wednesday morning through Thursday afternoon
before moving inland. This front will bring widespread gale force
winds with localized areas of storm force winds. Areas that will
experience the strongest winds are gaps that are prone to
funneling from the south. There is also expected to be widespread
gale force west- northwesterly winds behind this front with a
smaller area of storm force winds. Guidance shows consistency in
the boundary layer winds forecast with these winds reaching storm
force. Due to these storm force winds in the boundary layer
expected to be behind the cold front, it is very likely they will
mix down to the surface as the strong cold air advection will keep
the boundary layer coupled.

&&

.MARINE (Days 3 through 5: Friday through Sunday)...

Bering Sea: A low and trailing front approaching the Alaska
Peninsula from the west will bring widespread westerly gales with
an area of storm force winds and 30 feet seas moving with the
low, or north of the Eastern Aleutians on Fri morning. Winds
decrease to gales over the Eastern Bering by Sat with seas
decreasing to 20 feet. Another strong front moves north across the
Western Bering/Aleutians late Fri into Sat. High end westerly
gale force to possibly storm force winds and seas building to 25
feet over the Western Bering are expected for Sat. Some model
uncertainty persists, but overall confidence is good. A low
approaches the Central Aleutians from the North Pacific early Sun
with southerly gales spreading into the central Bering with seas
remaining in the mid-20s through Sun. Up to storm force winds are
again possible for parts of the central Bering with this next
system on Sun, but confidence for these higher winds is lower by
this point in the forecast.

Gulf of Alaska: A low and front trailing to the south of Kodiak
Island move into the western Gulf Fri with northwesterly gales
moving in over the western bering just behind low and front. Waves
build to 10 to 15 feet in the western Gulf on Fri and up to 20
feet in the southern Gulf by early Sat. Confidence for this
portion of the forecast is good, but uncertainty for the low track
increases as it drifts towards the central/northern Gulf on Sat.
There is better confidence for a region of at least northwesterly
gales to continue southwest of the low near the southeastern Gulf,
but the region of highest winds will depend on the uncertain low
track. By Sun, confidence increases for the low to exit into the
North Pacific with northerly winds decreasing to small crafts or
lower and seas subsiding to 10 feet by Sun evening.

&&

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

The models are in surprisingly good agreement at the start of this
forecast period, with only moderate agreement through the
weekend. The active pattern is expected to continue.

Models keep a strong Arctic/Siberian upper level low rotating
around northeast Russia with an attendant trough stretching
southeastward across western Alaska and the eastern Aleutians at
the start of the period. A shortwave moving along the trough
extending from the aforementioned upper low will help force a
lower level circulation which may develop over the Alaskan
Peninsula and track into the northern Gulf. While details are very
much uncertain with this and even farther out, there could be
another trough moving across the Aleutians and Bering at the end
of the forecast period.

Overall, expect milder temperatures for this time period with
readings still slightly below normal but closer to the normal
values of where they typically are this time of the year which is
near 32 degrees F for Anchorage. This pattern could potentially
mean a snowier regime for Southcentral and in particular across
the Anchorage Bowl. However, many factors have to come together
for Anchorage to get the snow, though, the storm track looks
favorable with model guidance mostly bringing lows near and into
Prince William Sound with details of each uncertain.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Blizzard Warning 155 185 195.
		 Winter Weather Advisory 181.
MARINE...Storm Warning 172 185 411.
		 Gale Warning 130 131 150 155 165 170 171 173-181 412-414.
		 Heavy Freezing Spray Warning 130 138 155 160 165 179 180
									  185 412 414.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...KO
SOUTHCENTRAL ALASKA...AP
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...ED
MARINE/LONG TERM...AS/NR