Storm Warning 178, NWS Anchorage, AK

383 
FZAK51 PAFC 231304
CWFAER

Coastal Waters Forecast
National Weather Service Anchorage Alaska
404 AM AKST Mon Nov 23 2020

Coastal Waters Forecast for the Northern Gulf of Alaska Coast
up to 100 nm out including Kodiak Island and Cook Inlet.

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.

PKZ197-240145-
404 AM AKST Mon Nov 23 2020
.SYNOPSIS FOR THE NORTH GULF COAST+KODIAK ISLAND WATERS+
COOK INLET...A 957 mb low 80 nm southeast of Kodiak City this
morning will move 550 nm southeast of Cordova at 984 mb Tuesday 
morning. A front moves across the Gulf of Alaska Tuesday night 
through Wednesday evening.

$$

PKZ119-240145-
Cape Suckling to Cape Cleare-
404 AM AKST Mon Nov 23 2020

...STORM WARNING TODAY...

.TODAY...E wind increasing to 55 kt then diminishing to 35 kt in the
afternoon. Near the coast, E wind 55 kt. Seas 14 ft early building to
24 ft. Rain.
.TONIGHT...NE wind 35 kt becoming N 25 kt after midnight. Seas 25 ft.
Rain showers.
.TUE...NW wind 25 kt. Seas 18 ft subsiding to 13 ft in the
afternoon.
.TUE NIGHT...SE wind 15 kt. Seas 10 ft.
.WED...S wind 40 kt. Seas 16 ft.
.THU...SW wind 30 kt. Seas 16 ft.
.FRI...SE wind 35 kt. Seas 13 ft.

$$

PKZ120-240145-
Cape Cleare to Gore Point-
404 AM AKST Mon Nov 23 2020

...STORM WARNING TODAY...

.TODAY...E wind increasing to 50 kt. Seas 19 ft early building to 26 ft.
Rain and snow.
.TONIGHT...N wind 40 kt becoming NW 30 kt after midnight. Seas
20 ft. Rain showers.
.TUE...NW wind 30 kt. Seas 13 ft.
.TUE NIGHT...SE wind 25 kt. Seas 8 ft.
.WED...SW wind 40 kt. Seas 17 ft.
.THU...W wind 30 kt. Seas 16 ft.
.FRI...SE wind 30 kt. Seas 17 ft.

$$

PKZ121-240145-
Resurrection Bay-
404 AM AKST Mon Nov 23 2020

...SMALL CRAFT ADVISORY THROUGH TONIGHT...

.TODAY...Variable wind 10 kt early becoming N 25 kt. Seas building 
to 5 ft. Higher winds and seas S of Caines Head. Rain and snow.
.TONIGHT...N wind 25 kt. Seas 5 ft.
.TUE...N wind 20 kt. Seas 4 ft.
.TUE NIGHT...Variable wind less than 10 kt. Seas 2 ft.
.WED...N wind 10 kt. Seas 2 ft.
.THU THROUGH FRI...Variable wind less than 10 kt. Seas 2 ft.

$$

PKZ125-240145-
Prince William Sound-
404 AM AKST Mon Nov 23 2020

...GALE WARNING TODAY...

.TODAY...NE wind 35 kt. Seas building to 9 ft. Rain and snow.
.TONIGHT...NW wind 30 kt. Seas 6 ft.
.TUE...NW wind 30 kt becoming N 20 kt in the afternoon. Seas 4 ft.
.TUE NIGHT...E wind 10 kt. Seas 2 ft.
.WED...SE wind 30 kt. Seas 7 ft.
.THU...W wind 15 kt. Seas 3 ft.
.FRI...E wind 25 kt. Seas 4 ft.

$$

PKZ126-240145-
Port Valdez-
404 AM AKST Mon Nov 23 2020

.TODAY...NE wind 10 kt increasing to 15 kt in the afternoon. Seas
3 ft. Snow with rain.
.TONIGHT...NE wind 15 kt diminishing to 10 kt after midnight. Seas
3 ft.
.TUE...NE wind 10 kt. Seas 2 ft.
.TUE NIGHT...NE wind 10 kt. Seas 2 ft.
.WED THROUGH FRI...NE wind 10 kt. Seas 2 ft.

$$

PKZ127-240145-
Valdez Narrows-
404 AM AKST Mon Nov 23 2020

...GALE WARNING THROUGH TONIGHT...

.TODAY...NE wind 25 kt increasing to 35 kt in the afternoon. Seas
4 ft. Snow with rain.
.TONIGHT...NE wind 35 kt diminishing to 20 kt after midnight. Seas
4 ft.
.TUE...NE wind 25 kt. Seas 3 ft.
.TUE NIGHT...NE wind 20 kt. Seas 3 ft.
.WED...NE wind 20 kt. Seas 3 ft.
.THU...SW wind 10 kt. Seas 2 ft.
.FRI...NE wind 10 kt. Seas 2 ft.

$$

PKZ128-240145-
Valdez Arm-
404 AM AKST Mon Nov 23 2020

...SMALL CRAFT ADVISORY THROUGH TONIGHT...

.TODAY...NE wind increasing to 30 kt. Seas building to 6 ft. Snow.
.TONIGHT...NE wind 25 kt. Seas 5 ft.
.TUE...NE wind 20 kt. Seas 4 ft.
.TUE NIGHT...NE wind 15 kt. Seas 3 ft.
.WED...NE wind 20 kt. Seas 4 ft.
.THU...SW wind 10 kt. Seas 2 ft.
.FRI...NE wind 15 kt. Seas 3 ft.

$$

PKZ129-240145-
Passage Canal-
404 AM AKST Mon Nov 23 2020

...SMALL CRAFT ADVISORY THROUGH TUESDAY...

.TODAY...E wind 25 kt. Seas 3 ft. Snow and rain.
.TONIGHT...W wind 25 kt. Gusts to 40 kt near Whittier developing
after midnight. Seas 4 ft.
.TUE...W wind 25 kt diminishing to 15 kt in the afternoon. Gusts to
40 kt near Whittier in the morning. Seas 4 ft subsiding to 2 ft in 
the afternoon.
.TUE NIGHT...E wind 10 kt. Seas 2 ft.
.WED...E wind 15 kt. Seas 2 ft.
.THU...Variable wind less than 10 kt. Seas 2 ft.
.FRI...E wind 10 kt. Seas 2 ft.

$$

PKZ130-240145-
West of Barren Islands including Kamishak Bay-
404 AM AKST Mon Nov 23 2020

...STORM WARNING TODAY...

.TODAY...NE wind 55 kt. Seas 28 ft subsiding to 19 ft in the
afternoon. Rain and snow.
.TONIGHT...NW wind 40 kt. Seas 18 ft.
.TUE...W wind 25 kt becoming SE in the afternoon. Seas 9 ft.
.TUE NIGHT...E wind 35 kt. Seas 16 ft.
.WED...W wind 40 kt. Seas 18 ft.
.THU...W wind 25 kt. Seas 5 ft.
.FRI...E wind 35 kt. Seas 9 ft.

$$

PKZ131-240145-
Barren Islands East-
404 AM AKST Mon Nov 23 2020

...HURRICANE FORCE WIND WARNING TODAY...

.TODAY...E wind 65 kt becoming N 45 kt in the afternoon. Seas 24 ft.
Rain with snow.
.TONIGHT...NW wind 40 kt. Seas 21 ft.
.TUE...W wind 30 kt becoming SW 20 kt in the afternoon. Seas 14 ft.
.TUE NIGHT...S wind 30 kt. Seas 10 ft.
.WED...SW wind 40 kt. Seas 17 ft.
.THU...SW wind 30 kt. Seas 15 ft.
.FRI...SE wind 35 kt. Seas 17 ft.

$$

PKZ132-240145-
Marmot Island to Sitkinak-
404 AM AKST Mon Nov 23 2020

...STORM WARNING THROUGH TONIGHT...

.TODAY...SW wind 40 kt becoming NW 55 kt in the afternoon. N of
Dangerous Cape, E wind 25 kt becoming N 45 kt in the afternoon.
Seas 31 ft except 24 ft N of Dangerous Cape. Rain.
.TONIGHT...NW wind 50 kt becoming W 40 kt after midnight. Seas 26 ft
subsiding to 20 ft after midnight.
.TUE...W wind 30 kt. Seas 15 ft.
.TUE NIGHT...S wind 40 kt. Seas 17 ft.
.WED...SW wind 35 kt. Seas 19 ft.
.THU...SW wind 25 kt. Seas 14 ft.
.FRI...S wind 35 kt. Seas 18 ft.

$$

PKZ136-240145-
Chiniak Bay-
404 AM AKST Mon Nov 23 2020

...GALE WARNING THROUGH TONIGHT...

.TODAY...NE wind 20 kt becoming NW 40 kt in the afternoon. Seas
8 ft. Rain with snow.
.TONIGHT...NW wind 35 kt. Gusts to 45 kt. Seas 6 ft.
.TUE...SW wind 15 kt. Seas 2 ft.
.TUE NIGHT...S wind 30 kt. Seas 5 ft.
.WED...SW wind 30 kt. Seas 5 ft.
.THU...S wind 20 kt. Seas 3 ft.
.FRI...S wind 25 kt. Seas 10 ft.

$$

PKZ137-240145-
Marmot Bay-
404 AM AKST Mon Nov 23 2020

...SMALL CRAFT ADVISORY THROUGH TONIGHT...

.TODAY...NE wind 30 kt. Seas 10 ft. Rain with snow.
.TONIGHT...NW wind 30 kt. Gusts to 40 kt. Seas 7 ft.
.TUE...W wind 20 kt becoming SE 15 kt in the afternoon. Seas 4 ft.
.TUE NIGHT...SE wind 30 kt. Seas 11 ft.
.WED...SW wind 30 kt. Seas 7 ft.
.THU...S wind 20 kt. Seas 4 ft.
.FRI...SE wind 30 kt. Seas 11 ft.

$$

PKZ138-240145-
Shelikof Strait-
404 AM AKST Mon Nov 23 2020

...STORM WARNING TODAY...

.TODAY...NE wind 50 kt. Seas 22 ft subsiding to 14 ft in the
afternoon. Rain.
.TONIGHT...NW wind 35 kt. Gusts to 50 kt out of western bays and
passes. Seas 8 ft subsiding to 5 ft after midnight.
.TUE...SW wind 25 kt. Seas 5 ft.
.TUE NIGHT...SE wind 30 kt. Seas 10 ft.
.WED...W wind 30 kt. Seas 9 ft.
.THU...W wind 20 kt. Seas 7 ft.
.FRI...E wind 30 kt. Seas 9 ft.

$$

PKZ139-240145-
Cook Inlet Kalgin Island to Point Bede-
404 AM AKST Mon Nov 23 2020

...STORM WARNING TODAY...

.TODAY...NE wind 50 kt. Seas 25 ft subsiding to 20 ft in the
afternoon.
.TONIGHT...N wind 15 kt becoming W 30 kt after midnight. Seas 9 ft. 
.TUE...W wind 20 kt becoming E in the afternoon. Seas 6 ft 
subsiding to 3 ft in the afternoon.
.TUE NIGHT...NE wind 25 kt. Seas 8 ft.
.WED...NW wind 30 kt. Seas 10 ft.
.THU...NW wind 20 kt. Seas 5 ft.
.FRI...NE wind 20 kt. Seas 5 ft.

$$

PKZ140-240145-
Cook Inlet North of Kalgin Island-
404 AM AKST Mon Nov 23 2020

...GALE WARNING TODAY...

.TODAY...N wind 40 kt. Seas 15 ft.
.TONIGHT...E wind 15 kt becoming W after midnight. Seas 5 ft
subsiding to 3 ft after midnight.
.TUE...NE wind 10 kt increasing to 15 kt in the afternoon. Seas
3 ft.
.TUE NIGHT...NE wind 15 kt. Seas 4 ft.
.WED...NW wind 25 kt. Seas 6 ft.
.THU...W wind 15 kt. Seas 3 ft.
.FRI...N wind 20 kt. Seas 5 ft.

$$

PKZ141-240145-
Kachemak Bay-
404 AM AKST Mon Nov 23 2020

...GALE WARNING TODAY...

.TODAY...NE wind 40 kt becoming N 30 kt in the afternoon. Seas 7 ft.
Snow and rain.
.TONIGHT...N wind 15 kt becoming W 20 kt after midnight. Seas 3 ft
building to 6 ft after midnight.
.TUE...SW wind 15 kt becoming E 10 kt in the afternoon. Seas 4 ft
subsiding to 2 ft in the afternoon.
.TUE NIGHT...E wind 20 kt. Seas 3 ft.
.WED...SW wind 30 kt. Seas 10 ft.
.THU...W wind 20 kt. Seas 4 ft.
.FRI...NE wind 20 kt. Seas 3 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
551 AM AKST Sun Nov 22 2020

.ANALYSIS AND UPPER LEVELS...

An active weather pattern continues across the area as an area of
low pressure moves northeastward in Cook Inlet along a
negatively-tilted trough that extends from the central Bering Sea
to the Pacific Northwest. A large upper level low extends across
the Bering Sea from Siberia to Southwest Alaska. The jetstream
remains south of 50N west of 178W then bulges northward to over
the eastern Aleutians before curving southeastward towards the
Pacific Northwest. The jetstream then splits with the southern
half extending eastward to over the CONUS while the northern half
curves northwestward to over Siberia and then northeastward into
the Arctic Ocean. A massive upper level ridge extends from the
western CONUS into the Arctic Ocean.

Closer to the surface, radar imagery shows snow showers moving
northeastward across the Anchorage Bowl and into the Mat-Su
Valley. Radar also shows showers moving northeastward across the
northern Gulf of Alaska into Prince William Sound. Observations
show the precipitation type as rain along the immediate coast as
temperatures remain above freezing. Farther inland precipitation
type is snow as temperatures are below freezing in these
locations.

&&

.MODEL DISCUSSION...

Guidance is in better agreement with the placement and intensity
of synoptic scale features in both the surface and upper levels in
the 22nd/00z runs compared to the 21st/00z runs 24hrs ago. A
consistent pattern for the next storm system expected to track
south of the Aleutians then move northeastward into the Gulf of
Alaska. All models show a similar 500mb pattern with a
negatively-tilted trough around the vorticity maxima. This
negative-tilt is a key factor in the model solutions at the
surface as all models show this storm system undergoing
bombogenesis (24mb decrease in a 24hr period) through Monday
morning as the storm system moves into the Gulf. That being said,
there is good agreement with this storm bringing widespread
hurricane force winds in the Gulf of Alaska on Monday. Guidance is
in good agreement with the placement and orientation of a front
moving across the Bering/Aleutians Sunday evening through Tuesday
night, though there are discrepancies on the strength of this
front and thus the more aggressive end of guidance shows storm-
force winds while the more conservative end only has Gale force
winds. Given that there is a consistent trend in the central
pressure of the low associated with this front being around 965
mb, the stronger solutions showing storm force surface winds is
the favored solution.

&&

.AVIATION...
PANC...IFR conditions are expected as light snow and mist continue
to reduce visibilities to near 1SM. Ceilings will predominantly
remain between 1000-2000ft AGL. Intermittent MVFR conditions are
expected through 18z as visibility will increase to 3SM at times
with ceilings intermittently rising to between 2000-3000ft AGL.
VFR conditions are expected after 21z as the bulk of the snow will
be over by then. MVFR conditions resume at 23rd/15z as ceilings
drop between 2000-3000ft AGL ahead of the next low pressure
system.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2...Sunday
and Monday)...If you like active weather, this forecast is for
you. First, an impressive closed low is driving up Cook Inlet.
This feature was responsible for dropping about 18 inches of snow
in Turnagain Pass on Saturday. It will continue to lift north
quickly this morning as it swings a few healthy snow bands across
the Anchorage Bowl and the Matanuska Valley. Any accumulations
should be limited to around an inch or so as it exits the area
later this morning. Snow could linger longer over higher
elevations such as Hatcher Pass and even over towards Thompson
Pass.

Then attention immediately shifts to an impressive low that will
take shape very quickly later today into Monday. This low will
form in the favored left exit region of a 170 kt 300mb (30,000')
jet. It will emerge from the Aleutians into the Western Gulf of AK
just after midnight tonight. This low will drop into the low 950
mb range as it skirts just south and east of Kodiak Island. Due to
this rapid cyclogenesis, winds will increase sharply across many
of the marine zones easily making into storm-force range with some
pockets of sustained hurricane-force winds near the Barren
Islands. This system will also bring a moderate shot of rain to
Kodiak City with over 2" expected in a 24 hour period. The highest
elevations of Kodiak will stay cold enough to see very heavy snow,
but temperatures at sea level will only support rain.

As this system wraps up near Kodiak Island, it will bring another
round of winter weather to much of the Prince William
Sound/Turnagain Pass Area. The one key difference from the weekend
system is that this storm will track further south. This should
allow for more cold air to remain over the mainland and keep
precipitation mostly snow. The few exceptions could be sites on
the immediate coast such as Seward and Whittier. Precipitation
amounts will also be slightly less than the weekend system due to
this track and how fast the storm passes through the Gulf.
Regardless, expect areas of blowing snow to develop in the
Turnagain Pass and over to Thompson Pass. Motorists with travel
plans through these areas should stay up to date on the latest
forecasts. The active weather will continue this week with yet
another system moving into the Gulf late Tue.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2: Sunday and
Monday)...

Generally quiet weather is expected across much of Southwest
today. There are a few snow showers around this morning
especially in the YK-Delta near Bethel, though, these are largely
expected to dissipate by 8-10 am this morning with any activity
remaining over the Kuskokwim Mountains and the western Alaska
Range. Temperatures have also remained up overnight across the
Bethel area, therefore, nudged min temperatures for this morning
up a couple degrees to account for this. Expect temperatures to
remain fairly steady throughout the daylight hours before colder
air begins to filter in later this afternoon and into the evening
hours.

Attention then turns to a strong area of low pressure currently
developing to the south of the Aleutian Chain in the North
Pacific. This low is expected to keep rapidly deepening as it
continues to move off to the north and east reaching the western
Gulf of Alaska by Monday morning. On the north and west side of
the storm track, expect snow to overspread much of Bristol Bay
beginning this evening and continuing through Monday morning.
Areas along the AKPEN such as Egegik to Pilot Point to Port
Heiden will be near the area of warmer air as the low passes by to
the south of the region. This will cause a mix of rain/snow
especially from this evening into the early morning hours Monday
before the flow turns to more northwesterly and colder air filters
in to change any mix or rain to all snow. Farther north and west,
areas such as Dillingham to Egegik but west of King Salmon have
the risk for a deformation band to develop. If this occurs, higher
snowfall amounts can be expected. A Winter Weather Advisory was
issued with this forecast package from 10 PM this evening to 9 AM
Monday morning for snow and blowing snow. North winds of 15-25
mph and gusts 30-35 mph may reduce visibilities to a half mile or
less in blowing snow. Expect the steadiest and heaviest snow
overnight into the early morning hours before tapering off to
snow showers later Monday morning and then ending by afternoon.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2:
Sunday through Monday)...

A rapidly deepening storm system currently southeast of Adak will
continue moving to the north and east reaching the Gulf of Alaska
by Monday morning. Expect periods of rain and strong gusty winds
along the central and eastern Aleutian Chain today through
tonight. As a result of this rapidly deepening storm system, rapid
pressure rises and cold air advection on the back side of the low
will create for very windy conditions across the Pacific side
marine zones this afternoon through Monday afternoon. Storm force
winds are expected to develop across the marine area south of
Dutch Harbor this afternoon and are expected to continue through
early Monday morning. Winds will continue to increase to the east
across the marine waters south of Sand Point to south of Kodiak
Island this evening through Monday evening. Hurricane force wind
warnings are out for the marine zones south of Sand Point and
south of Kodiak Island beginning this evening and continuing
through Monday evening. Wave heights in the Pacific side marine
zones south of the AKPEN and the eastern Aleutian Islands are
expected to be anywhere from 30-40ft with the highest waves the
furthest offshore. Areas on the Bering side will also see gale and
storm force winds with wave heights of 15-22ft Sunday evening
through Monday evening.

Another developing storm system over the North Pacific to the
southwest of the western Aleutians will send a storm force front
through the Bering Sea beginning this evening reaching the
eastern Bering by early Tuesday morning. Periods of rain will
accompany the front as a strong push of warm air northward occurs.
Cold air wraps in the back side that will provide the chance for
snow showers as colder air filters in. Wave heights with the front
will be anywhere from 20-28ft.

&&

.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...Winter Weather Advisory 161.
MARINE...Hurricane Force Wind Warning 131 150 155.
Storm Warning 119 120 132 138 139 160 165 172 175 177 178 351 352 411 413.
Gale Warning 125 136 137 140 141 170 171 173 174 176 179 180 185 412 414.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...ED
SOUTHCENTRAL ALASKA...MO
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MV
MARINE/LONG TERM...RC