Small Craft Advisory 151, NWS Anchorage, AK

530 
FZAK51 PAFC 150001
CWFAER

Coastal Waters Forecast
National Weather Service Anchorage Alaska
301 PM AKST Fri Feb 14 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.

PKZ197-151245-
301 PM AKST Fri Feb 14 2020
.SYNOPSIS FOR THE NORTH GULF COAST+KODIAK ISLAND WATERS+
COOK INLET...

A front over the central Gulf remains nearly stationary through
Sun afternoon. A weak trough along the north Gulf coast persists
through Sat night, then dissipates. A stronger front enters the
southern Gulf Sun morning, moving into the central Gulf Sun
afternoon.

$$

PKZ119-151245-
Cape Suckling to Cape Cleare-
301 PM AKST Fri Feb 14 2020

...SMALL CRAFT ADVISORY SATURDAY NIGHT...

.TONIGHT...NE wind 15 kt. Seas 6 ft.
.SAT...Variable wind 10 kt becoming W 20 kt in the afternoon. 
Seas 7 ft.
.SAT NIGHT...NW wind 20 kt. Seas 8 ft.
.SUN...W wind 15 kt. Seas 7 ft.
.SUN NIGHT...SE wind 25 kt. Seas 7 ft.
.MON...SE wind 35 kt. Seas 13 ft.
.TUE...S wind 35 kt. Seas 19 ft.
.WED...SW wind 25 kt. Seas 19 ft.

$$

PKZ120-151245-
Cape Cleare to Gore Point-
301 PM AKST Fri Feb 14 2020

...SMALL CRAFT ADVISORY SATURDAY AND SATURDAY NIGHT...

.TONIGHT...NE wind 15 kt. Seas 6 ft.
.SAT...W wind 25 kt. Seas 7 ft.
.SAT NIGHT...W wind 25 kt. Seas 7 ft.
.SUN...W wind 15 kt. Seas 6 ft.
.SUN NIGHT...E wind 15 kt. Seas 6 ft.
.MON...SE wind 30 kt. Seas 15 ft.
.TUE...S wind 30 kt. Seas 18 ft.
.WED...SW wind 25 kt. Seas 18 ft.

$$

PKZ121-151245-
Resurrection Bay-
301 PM AKST Fri Feb 14 2020

.TONIGHT...N wind 10 kt. Seas 2 ft.
.SAT...N wind 10 kt increasing to 15 kt in the afternoon. 
Seas 3 ft. Freezing spray.
.SAT NIGHT...N wind 15 kt diminishing to 10 kt after midnight.
Seas 3 ft. Freezing spray.
.SUN...N wind 10 kt. Seas 2 ft.
.SUN NIGHT...Variable wind less than 10 kt. Seas 2 ft.
.MON...S wind 15 kt. Seas 3 ft.
.TUE THROUGH WED...N wind 20 kt. Seas 4 ft.

$$

PKZ125-151245-
Prince William Sound-
301 PM AKST Fri Feb 14 2020

.TONIGHT...N wind 10 kt. Seas 2 ft.
.SAT...Variable wind less than 10 kt becoming N 10 kt 
in the afternoon. Seas 2 ft.
.SAT NIGHT...NW wind 10 kt in the evening becoming 
variable less than 10 kt. Seas 2 ft.
.SUN...Variable wind less than 10 kt. Seas 2 ft.
.SUN NIGHT...NE wind 15 kt. Seas 3 ft.
.MON THROUGH TUE...SE wind 25 kt. Seas 6 ft.
.WED...S wind 20 kt. Seas 4 ft.

$$

PKZ126-151245-
Port Valdez-
301 PM AKST Fri Feb 14 2020

.TONIGHT...Variable wind less than 10 kt. Seas 2 ft.
.SAT...Variable wind less than 10 kt. Seas 2 ft.
.SAT NIGHT...NE wind 10 kt. Seas 2 ft.
.SUN AND SUN NIGHT...Variable wind less than 10 kt. Seas 2 ft.
.MON THROUGH WED...Variable wind less than 10 kt. Seas 2 ft.

$$

PKZ127-151245-
Valdez Narrows-
301 PM AKST Fri Feb 14 2020

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...NE wind 30 kt decreasing to 15 kt after midnight. 
Seas 3 ft. Freezing spray.
.SAT...NE wind 15 kt. Seas 3 ft. Freezing spray.
.SAT NIGHT...NE wind 10 kt. Seas 2 ft.
.SUN...NE wind 10 kt. Seas 2 ft.
.SUN NIGHT...NE wind 20 kt. Seas 3 ft.
.MON THROUGH TUE...NE wind 20 kt. Seas 3 ft.
.WED...NE wind 10 kt. Seas 2 ft.

$$

PKZ128-151245-
Valdez Arm-
301 PM AKST Fri Feb 14 2020

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...NE wind 25 kt becoming NE 10 kt after midnight. 
Seas 5 ft subsiding to 2 ft after midnight.
.SAT...NE wind 10 kt. Seas 2 ft.
.SAT NIGHT...NE wind 10 kt in the evening becoming 
variable less than 10 kt. Seas 2 ft.
.SUN...Variable wind less than 10 kt. Seas 2 ft.
.SUN NIGHT...NE wind 15 kt. Seas 3 ft.
.MON...NE wind 15 kt. Seas 3 ft.
.TUE THROUGH WED...Variable wind 15 kt. Seas 3 ft.

$$

PKZ129-151245-
Passage Canal-
301 PM AKST Fri Feb 14 2020

.TONIGHT...Variable wind less than 10 kt. Seas 2 ft.
.SAT...W wind 10 kt increasing to 15 kt in the afternoon. 
Seas 2 ft. Freezing spray.
.SAT NIGHT...W wind 10 kt. Seas 2 ft.
.SUN...Variable wind less than 10 kt. Seas 2 ft.
.SUN NIGHT...Variable wind less than 10 kt. Seas 2 ft.
.MON THROUGH TUE...E wind 15 kt. Seas 2 ft.
.WED...Variable wind less than 10 kt. Seas 2 ft.

$$

PKZ130-151245-
West of Barren Islands including Kamishak Bay-
301 PM AKST Fri Feb 14 2020

.TONIGHT...NE wind 15 kt. Seas 4 ft.
.SAT...Variable wind 10 kt. Seas 2 ft.
.SAT NIGHT...Variable wind 10 kt. Seas 2 ft.
.SUN...NE wind 15 kt. Seas 4 ft.
.SUN NIGHT...E wind 25 kt. Seas 7 ft.
.MON...SE wind 35 kt. Seas 13 ft.
.TUE THROUGH WED...SW wind 15 kt. Seas 5 ft.

$$

PKZ131-151245-
Barren Islands East-
301 PM AKST Fri Feb 14 2020

.TONIGHT...NW wind 15 kt. Seas 6 ft.
.SAT...W wind 20 kt. Seas 6 ft.
.SAT NIGHT...W wind 20 kt. Seas 7 ft.
.SUN...SW wind 15 kt. Seas 6 ft.
.SUN NIGHT...S wind 20 kt. Seas 8 ft.
.MON...SE wind 35 kt. Seas 16 ft.
.TUE THROUGH WED...SW wind 25 kt. Seas 17 ft.

$$

PKZ132-151245-
Marmot Island to Sitkinak-
301 PM AKST Fri Feb 14 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY NIGHT...

.TONIGHT...W wind 20 kt. Seas 11 ft.
.SAT...W wind 30 kt. Seas 11 ft.
.SAT NIGHT...W wind 25 kt. Seas 11 ft.
.SUN...SW wind 25 kt. Seas 9 ft.
.SUN NIGHT...S wind 30 kt. Seas 12 ft.
.MON...S wind 35 kt. Seas 18 ft.
.TUE THROUGH WED...SW wind 30 kt. Seas 21 ft.

$$

PKZ136-151245-
Chiniak Bay-
301 PM AKST Fri Feb 14 2020

.TONIGHT...W wind 10 kt in the evening becoming variable 
less than 10 kt. Seas 2 ft.
.SAT...Variable wind less than 10 kt becoming W 10 kt 
in the afternoon. Seas 2 ft.
.SAT NIGHT...SW wind 10 kt. Seas 2 ft.
.SUN...S wind 10 kt. Seas 3 ft.
.SUN NIGHT...S wind 20 kt. Seas 3 ft.
.MON...S wind 30 kt. Seas 10 ft.
.TUE THROUGH WED...SW wind 20 kt. Seas 3 ft.

$$

PKZ137-151245-
Marmot Bay-
301 PM AKST Fri Feb 14 2020

.TONIGHT...W wind 10 kt. Seas 2 ft.
.SAT...W wind 10 kt increasing to 15 kt in the afternoon. 
Seas 3 ft.
.SAT NIGHT...W wind 15 kt becoming SW 10 kt after midnight. 
Seas 3 ft.
.SUN...S wind 10 kt. Seas 3 ft.
.SUN NIGHT...S wind 15 kt. Seas 3 ft.
.MON...SE wind 30 kt. Seas 9 ft.
.TUE THROUGH WED...SW wind 15 kt. Seas 3 ft.

$$

PKZ138-151245-
Shelikof Strait-
301 PM AKST Fri Feb 14 2020

.TONIGHT...Variable wind 10 kt. Seas 2 ft.
.SAT...SW wind 20 kt. Seas building to 6 ft.
.SAT NIGHT...SW wind 20 kt diminishing to 10 kt after midnight. 
Seas 6 ft subsiding to 3 ft after midnight.
.SUN...E wind 15 kt. Seas 4 ft.
.SUN NIGHT...S wind 20 kt. Seas 4 ft.
.MON...SE wind 20 kt. Seas 5 ft.
.TUE THROUGH WED...SW wind 25 kt. Seas 6 ft.

$$

PKZ139-151245-
Cook Inlet Kalgin Island to Point Bede-
301 PM AKST Fri Feb 14 2020

.TONIGHT...N wind 15 kt diminishing to 10 kt after midnight. Seas
in ice free waters 4 ft. Freezing spray.
.SAT...N wind 10 kt. Seas in ice free waters 3 ft.
.SAT NIGHT...Variable wind less than 10 kt becoming N 10 kt after
midnight. Seas in ice free waters 2 ft.
.SUN...N wind 15 kt. Seas in ice free waters 4 ft.
.SUN NIGHT...NE wind 20 kt. Seas in ice free waters 6 ft.
.MON...NE wind 20 kt. Seas in ice free waters 6 ft.
.TUE THROUGH WED...SW wind 15 kt. Seas in ice free waters 3 ft.

$$

PKZ140-151245-
Cook Inlet North of Kalgin Island-
301 PM AKST Fri Feb 14 2020

.TONIGHT...Variable wind less than 10 kt.
.SAT...Variable wind less than 10 kt.
.SAT NIGHT...Variable wind less than 10 kt.
.SUN...N wind 10 kt.
.SUN NIGHT...N wind 15 kt.
.MON...NE wind 15 kt.
.TUE THROUGH WED...S wind 10 kt.

$$

PKZ141-151245-
Kachemak Bay-
301 PM AKST Fri Feb 14 2020

.TONIGHT...Variable wind less than 10 kt. Seas 2 ft. Snow.
.SAT...Variable wind less than 10 kt. Seas 2 ft.
.SAT NIGHT...Variable wind less than 10 kt. Seas 2 ft.
.SUN...Variable wind less than 10 kt. Seas 2 ft.
.SUN NIGHT...E wind 10 kt. Seas 2 ft.
.MON...SE wind 20 kt. Seas 3 ft.
.TUE THROUGH WED...SW wind 10 kt. Seas 2 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
441 PM AKST Thu Feb 13 2020

.ANALYSIS AND UPPER LEVELS...
An upper level ridge is over most of mainland Alaska this
afternoon with an upper level low over the central Bering Sea. The
strong surface low near the western Aleutians is tracking
northward and will become vertically stacked with the upper level
low soon.
This low in the western Aleutians is quite impressive-looking on
satellite as it has occluded and has wrapped itself up into three
frontal bands.
Also notable on satellite is the inflection along the front well
southwest of Kodiak Island where the jet stream continues moving
southwest-to-northeast toward the Gulf and the lower-level features
along the surface front break to the north-northwest. This area
will induce a triple-point low to develop this evening which will
track across the southern Gulf of Alaska through tomorrow night.

&&

.MODEL DISCUSSION...
Models remain in good agreement with the large Bering Sea low into
the weekend, but then start to really struggle with the track,
structure, and strength of the next low that will be approaching
the western or central Aleutians by Saturday night. About the only
information that can be determined at this point is that there
will be a large low that impacts all of southern Alaska during the
first part of next week.

&&

.AVIATION...
PANC...VFR conditions and light winds will persist.

&&

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

Offshore flow will continue through tomorrow as the upper level
ridge weakens and moves overhead of Southcentral. This coincides
with weakening pressure and thermal gradients which will diminish
gap winds across the north Gulf coast and Prince William Sound.
Colder and drier conditions will remain across Southcentral
tomorrow through Saturday under the influence of the upper ridge.

A vertically stacked occluded low over the western Aleutians has
started to weaken, with its associated frontal system elongating
and weakening across the eastern Bering and Alaska Peninsula. This
frontal system will approach Kodiak Island tonight, bringing
snowfall to the Island tonight through Friday morning. Zonal flow
aloft will drive the triple point eastward across the Gulf, with a
low forming and deepening on its journey across the Gulf. As the
low develops the remaining occluded front will quickly fall apart
as it lifts northward toward the Kenai Peninsula. Thus, expect
little or no precipitation from this front to reach the Kenai
Peninsula. However, an upper level short-wave will approach Homer
and the Kenai Peninsula on Friday. Have increased the probability
of snow from chance to likely Friday night into Saturday morning
due to the combination of this shortwave trough and an upslope
component. Any snow that does fall will be light, with little snow
accumulation.

Forecast confidence really breaks down as we head through the
remainder of the weekend, with an active storm pattern across the
Bering Sea and Aleutians. There is a chance a frontal system from
one of these lows could reach Kodiak Island and the Gulf as early
as Sunday, bringing another round precipitation. For the rest of
Southcentral, the upper ridge will exit and will get into a broad
area of weak cyclonic flow aloft. This will likely lead to
increasing clouds, but chances of precipitation will remain low.

&&

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

An upper level ridge situated over western Alaska will break down
as the frontal boundary associated with a Western Bering low
pressure system moves into Southwest Alaska. Much of southwest
Alaska will see snow chances increase over the next 48 hours as
this system moves through. Temperatures will also be on the
increase thanks to some onshore air replacing the colder offshore
flow that has dominated the region recently. This also looks to
be the beginning of a more active pattern as model guidance is
hinting at some bigger changes.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...

A weakening gale force low remains in place in the Western Bering
this afternoon. The central Aleutians and westward will see gale
force winds and rain and snow showers continue through Friday
night then taper off early Saturday. A similar pattern develops
for the Pribilofs with slightly lighter winds and a rain and snow
mix Friday through Saturday.

&&

.MARINE (Days 3 through 5/Sunday through Tuesday)...

A high amplitude upper level pattern will be in place by Sunday.
This is favorable for a series of deep lows to move quickly across
the forecast area. On Sunday, the primary low will be located
back along the Aleutians. Expect lows to form out ahead of this
low across the North Pacific and track northward. These will
initially move into the Bering Sea, but each successive low will
form and track farther east, affecting the Southwest Alaska
coastal waters and the Gulf of Alaska.

Forecast confidence in the pattern and overall storm track is
high, while confidence in the track or strength of any individual
storm is low. Expect fairly widespread gales across the Bering
Sea for most of the Sunday through Tuesday period, with gales
likely over the Gulf Monday through Tuesday. There is also
potential for one or more of these systems to reach storm force.

&&

.LONG TERM FORECAST (Days 3 through 7)...

Beginning the extended period forecast on Saturday evening, there
will be a fast zonal flow pattern in place as a series of subtle
shortwave trough features in westerly flow will be impacting the
Southern Mainland and Bering Sea. Snow showers will mainly be
across Southwest Alaska and the Gulf given the blocking pattern
the Alaska Range induces on air moving from the west into
Southcentral. Arctic high pressure will remain over Southcentral,
so temps there will remain below average, but otherwise, expect
quiet weather through Sunday.

Thereafter, a significant storm is likely Sunday evening through
Tuesday as a strong Pacific trough digs and amplifies the flow
pattern. What is known now is a warm front will into Southwest
then Southcentral Sunday night into early Monday. Thereafter, the
global numerical guidance among the ECMWF, Canadian GDPS, and GFS
diverge rapidly with the trough orientation and the possibility of
a strong low moving inland. With that said, they all depict a
potentially major storm for much of the Mainland with impacts
ranging from heavy snow to strong winds and coastal rain (with
heavy higher elevation snow for the Gulf Coast. The details remain
uncertain, but the signal is very strong and confidence is growing
dramatically that there will be a storm, just exactly how it
unfolds remains unseen. Stay tuned.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Gales 127 173-178 185 352 411-413.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...EZ
SOUTHCENTRAL ALASKA...SEB/CK
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...LB
MARINE/LONG TERM...SEB/JA