Small Craft Advisory 550, NWS Anchorage, AK

928 
FZAK51 PAFC 122343
CWFAER

Coastal Waters Forecast
National Weather Service Anchorage Alaska
343 PM AKDT Mon Jul 12 2021

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.

PKZ197-131300-
343 PM AKDT Mon Jul 12 2021
.SYNOPSIS FOR THE NORTH GULF COAST+KODIAK ISLAND WATERS+
COOK INLET...

A 1008 mb low 140 nm southeast of Kodiak City remains nearly
stationary over the Gulf of Alaska then drifts to 240 nm southeast 
of Kodiak City by Wed afternoon. Its front extends along the North 
Gulf Coast through Tue afternoon.

$$

PKZ119-131300-
Cape Suckling to Cape Cleare-
343 PM AKDT Mon Jul 12 2021

...SMALL CRAFT ADVISORY TUESDAY...

.TONIGHT...E wind 20 kt. Seas 7 ft.
.TUE...E wind 25 kt. Seas 6 ft.
.TUE NIGHT...E wind 15 kt. Seas 5 ft.
.WED...Variable wind 10 kt. Seas 4 ft.
.WED NIGHT...Variable wind 10 kt. Seas 3 ft.
.THU...Variable wind 10 kt. Seas 3 ft.
.FRI...Variable wind 10 kt. Seas 3 ft.
.SAT...SW wind 15 kt. Seas 3 ft.

$$

PKZ120-131300-
Cape Cleare to Gore Point-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...NE wind 20 kt. Seas 7 ft. Rain.
.TUE...NE wind 20 kt. Seas 6 ft.
.TUE NIGHT...NE wind 20 kt. Seas 5 ft.
.WED...Variable wind 10 kt. Seas 4 ft.
.WED NIGHT...Variable wind 10 kt. Seas 3 ft.
.THU THROUGH SAT...SW wind 15 kt. Seas 3 ft.

$$

PKZ121-131300-
Resurrection Bay-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...N wind 10 kt. Seas 2 ft. Rain.
.TUE...Variable wind less than 10 kt becoming S 10 kt in the
afternoon. Seas 2 ft.
.TUE NIGHT...S wind 10 kt becoming N after midnight. Seas 2 ft.
.WED...S wind 10 kt. Seas 2 ft.
.WED NIGHT...N wind 10 kt. Seas 2 ft.
.THU...N wind 15 kt. Seas 3 ft.
.FRI...Variable wind 15 kt. Seas 3 ft.
.SAT...S wind 10 kt. Seas 2 ft.

$$

PKZ125-131300-
Prince William Sound-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...NE wind 15 kt. Seas 3 ft.
.TUE...NE wind 15 kt. Seas 3 ft.
.TUE NIGHT...NE wind 15 kt becoming N 10 kt after midnight. Seas
2 ft.
.WED AND WED NIGHT...W wind 10 kt. Seas 2 ft.
.THU...Variable wind less than 10 kt. Seas 2 ft.
.FRI...W wind 10 kt. Seas 2 ft.
.SAT...Variable wind less than 10 kt. Seas 2 ft.

$$

PKZ126-131300-
Port Valdez-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...W wind 10 kt in the evening becoming variable less than
10 kt. Seas 2 ft. Rain.
.TUE...Variable wind less than 10 kt becoming SW 10 kt in the
afternoon. Seas 2 ft.
.TUE NIGHT...W wind 10 kt in the evening becoming variable less
than 10 kt. Seas 2 ft.
.WED AND WED NIGHT...W wind 10 kt. Seas 2 ft.
.THU...W wind 10 kt. Seas 2 ft.
.FRI...Variable wind 10 kt. Seas 2 ft.
.SAT...SW wind 10 kt. Seas 2 ft.

$$

PKZ127-131300-
Valdez Narrows-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...SE wind 15 kt in the evening becoming N after midnight. 
Seas 3 ft. Rain.
.TUE...NE wind 10 kt becoming SW in the afternoon. Seas 2 ft.
.TUE NIGHT...SW wind 10 kt in the evening becoming variable less
than 10 kt. Seas 2 ft.
.WED...SW wind 15 kt. Seas 3 ft.
.WED NIGHT...N wind 15 kt. Seas 3 ft.
.THU THROUGH FRI...SW wind 15 kt. Seas 3 ft.
.SAT...SW wind 10 kt. Seas 2 ft.

$$

PKZ128-131300-
Valdez Arm-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...Variable wind 10 kt. Seas 2 ft. Rain.
.TUE...Variable wind less than 10 kt becoming SW 10 kt in the
afternoon. Seas 2 ft.
.TUE NIGHT...SW wind 10 kt in the evening becoming variable less 
than 10 kt. Seas 2 ft.
.WED AND WED NIGHT...SW wind 10 kt. Seas 2 ft.
.THU THROUGH SAT...SW wind 10 kt. Seas 2 ft.

$$

PKZ129-131300-
Passage Canal-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...E wind 10 kt increasing to 15 kt after midnight. Seas
2 ft. Rain.
.TUE...E wind 10 kt in the morning becoming variable less than
10 kt. Seas 2 ft.
.TUE NIGHT...Variable wind less than 10 kt. Seas 2 ft.
.WED AND WED NIGHT...W wind 10 kt. Seas 2 ft.
.THU THROUGH FRI...W wind 10 kt. Seas 2 ft.
.SAT...E wind 10 kt. Seas 2 ft.

$$

PKZ130-131300-
West of Barren Islands including Kamishak Bay-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...Variable wind 10 kt. Seas 3 ft.
.TUE...SE wind 15 kt. Seas 4 ft.
.TUE NIGHT...S wind 15 kt. Seas 3 ft.
.WED...Variable wind 10 kt. Seas 3 ft.
.WED NIGHT...SW wind 20 kt. Seas 5 ft.
.THU...W wind 20 kt. Seas 6 ft.
.FRI THROUGH SAT...W wind 15 kt. Seas 4 ft.

$$

PKZ131-131300-
Barren Islands East-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...N wind 15 kt. Seas 7 ft.
.TUE...NE wind 20 kt. Seas 6 ft.
.TUE NIGHT...NE wind 20 kt. Seas 6 ft.
.WED...N wind 15 kt. Seas 4 ft.
.WED NIGHT...SW wind 15 kt. Seas 3 ft.
.THU...W wind 20 kt. Seas 3 ft.
.FRI THROUGH SAT...W wind 15 kt. Seas 4 ft.

$$

PKZ132-131300-
Marmot Island to Sitkinak-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...NW wind 15 kt. Seas 6 ft.
.TUE...N wind 15 kt. Seas 5 ft.
.TUE NIGHT...N wind 15 kt. Seas 5 ft.
.WED...N wind 15 kt. Seas 4 ft.
.WED NIGHT...W wind 15 kt. Seas 4 ft.
.THU THROUGH FRI...W wind 20 kt. Seas 5 ft.
.SAT...W wind 15 kt. Seas 5 ft.

$$

PKZ136-131300-
Chiniak Bay-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...NW wind 15 kt diminishing to 10 kt after midnight. Seas
2 ft. Rain.
.TUE...N wind 10 kt. Seas 2 ft. Rain.
.TUE NIGHT...N wind 10 kt. Seas 2 ft.
.WED...N wind 10 kt. Seas 3 ft.
.WED NIGHT...S wind 10 kt. Seas 3 ft.
.THU THROUGH SAT...SW wind 10 kt. Seas 2 ft.

$$

PKZ137-131300-
Marmot Bay-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...NW wind 10 kt. Seas 2 ft. Rain.
.TUE...Variable wind less than 10 kt becoming NE 10 kt in the
afternoon. Seas 3 ft. Rain.
.TUE NIGHT...NE wind 10 kt. Seas 3 ft.
.WED...Variable wind less than 10 kt. Seas 3 ft.
.WED NIGHT...SW wind 10 kt. Seas 2 ft.
.THU THROUGH SAT...W wind 10 kt. Seas 2 ft.

$$

PKZ138-131300-
Shelikof Strait-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...Variable wind 10 kt. Seas 2 ft.
.TUE...Variable wind 10 kt becoming NE 15 kt in the afternoon. Seas 
2 ft building to 4 ft in the afternoon.
.TUE NIGHT...NE wind 15 kt. Seas 4 ft.
.WED...Variable wind 10 kt. Seas 3 ft.
.WED NIGHT...SW wind 15 kt. Seas 4 ft.
.THU THROUGH SAT...W wind 15 kt. Seas 4 ft.

$$

PKZ139-131300-
Cook Inlet Kalgin Island to Point Bede-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...NW wind 15 kt becoming S 10 kt after midnight. Seas 3
ft. Rain.
.TUE...Variable wind 10 kt. Seas 3 ft.
.TUE NIGHT...SW wind 10 kt increasing to 20 kt after midnight.
Seas 5 ft.
.WED...S wind 20 kt. Seas 4 ft.
.WED NIGHT...S wind 10 kt. Seas 3 ft.
.THU...Variable wind less than 10 kt. Seas 2 ft.
.FRI THROUGH SAT...SW wind 10 kt. Seas 3 ft.

$$

PKZ140-131300-
Cook Inlet North of Kalgin Island-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...Variable wind less than 10 kt becoming NE 10 kt after
midnight. Seas 2 ft. Rain.
.TUE...NE wind 10 kt increasing to 15 kt in the afternoon. Seas
3 ft. Rain.
.TUE NIGHT...NE wind 10 kt in the evening becoming SE 15 kt. Seas 4 
ft.
.WED...SW wind 15 kt. Seas 4 ft.
.WED NIGHT...SW wind 10 kt. Seas 3 ft.
.THU...Variable wind less than 10 kt. Seas 2 ft.
.FRI THROUGH SAT...SW wind 10 kt. Seas 3 ft.

$$

PKZ141-131300-
Kachemak Bay-
343 PM AKDT Mon Jul 12 2021

.TONIGHT...SW wind 10 kt in the evening becoming variable less
than 10 kt. Seas 2 ft. Rain.
.TUE...Variable wind less than 10 kt becoming W 10 kt in the
afternoon. Seas 2 ft. Rain.
.TUE NIGHT...SW wind 10 kt in the evening becoming variable less
than 10 kt. Seas 2 ft.
.WED...Variable wind less than 10 kt. Seas 2 ft.
.WED NIGHT...Variable wind less than 10 kt. Seas 2 ft.
.THU THROUGH FRI...Variable wind less than 10 kt. Seas 2 ft.
.SAT...SW wind 10 kt. Seas 2 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
609 PM AKDT Sun Jul 11 2021

.ANALYSIS AND UPPER LEVELS...

The longwave pattern is dominated by an upper-level low situated
just east of Kodiak Island and an upper-level ridge upstream over
eastern Siberia and extending across the central Bering. At the
surface, a 1003 mb low is currently spinning over the central
Gulf with a southerly flow ahead of it continuing to push clouds
and rain along the Southcentral coast. Easterly gales persist
across the northern Gulf, with peak gusts of 45 kt at Middleton
Island and Hinchinbrook Island. One weak shortwave embedded in the
easterly flow has moved from Cook Inlet to the Alaska Range with
showers from Homer to Anchorage. A second wave is pushing across
Prince William Sound this afternoon. Farther inland, mid-level
clouds have moved over the Copper River Basin and Susitna Valley.

Scattered showers are moving over the Kuskokwim Delta from the
north as a shortwave trough and surface cold front drop south
from northern Alaska. Farther west, low stratus and areas of fog
persist from the Pribilof Islands and eastern Aleutians west
across the Bering. A weak vertically stacked low sits north of
Shemya.

&&

.MODEL DISCUSSION...

Model agreement continues to improve in the near term, especially
with the timing of various easterly shortwaves pinwheeling around
the main upper-level low centered over the central Gulf. The 12z
GFS has now trended to the other 12z models with regard to the
wave lifting across Southcentral Tuesday evening through
Wednesday. All models, including hi-res guidance, are indicating a
band of precipitation developing over the Copper River Basin by
Monday evening, moving to the Susitna Valley by Tuesday morning as
another area of rain develops from Cook Inlet to Kodiak Island.
The GFS does diverge from the other models Wednesday, keeping the
aforementioned low lingering over the central Gulf while other
guidance moves this feature east. However, given that the low is
rapidly weakening, there are no significant differences in the
sensible weather.

&&

.AVIATION...

PANC...VFR ceilings will persist. A stray shower or two are
likely late afternoon through this evening in association with a
weak upper-level wave moving overhead. Winds are expected to
remain light through Monday morning. A light southeasterly
Turnagain Arm wind may bend over the terminal this afternoon. An
occasional higher gust is also possible; however, confidence in
this is low and is not included in the TAF.

&&

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

The main weather player for the start of the week will continue to
be the increasingly stacked and occluded low centered over the
Gulf. The gale force barrier jet following the contour of the
low's front will slowly diminish through tomorrow as the front
gradually weakens in place along the north Gulf Coast. This same
front will continue to bring steady rainfall to most coastal
locations through at least Tuesday morning. Farther inland, the
first of a series of easterly waves may bring enough forcing to
generate a brief round of showers along the western Kenai
Peninsula and perhaps into the Anchorage vicinity this evening.
Rainfall chances have been increased here for this forecast
update to account for this potential, but any showers will be
light and short-lived with the supporting impulse racing quickly
southeast into Kodiak Island by tomorrow morning.

A much more robust threat for inland rainfall will move across
with a deeper easterly wave pinwheeling around the low in the Gulf
by tomorrow evening into early Tuesday. A band of rain will move
inland from east to west as the wave axis moves across, bringing a
decent surge of moisture that could result in wetting rains well
away from the coast, including much of the Mat-Su Valleys and
Copper River Basin. Rain will similarly end from east to west on
Tuesday as the wave pivots into Kodiak Island by Tuesday
afternoon.

The beginnings of what could become some of the first "real"
summer weather this season will start to come together with a
pattern shift on Wednesday. An upper level ridge will build into
the western mainland by midweek as the filling and weakening low
in the Gulf finally accelerates into the AK Panhandle. This will
bring a shift to northerly flow from the interior, with much
warmer and drier air beginning to spill in across the Alaska Range
by Wednesday afternoon. The one exception to the drying trend may
be the Copper River Basin, where another shortwave tracking around
the ridge from the north could bring lingering cloud cover and
showers for one more day before more significant warming takes
hold across the whole region later this week.

&&

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

A quiet weather pattern will continue across Southwest Alaska over
the next few days. Overall, skies will have more clouds than
sun and the chance of stray showers still exists. Otherwise, the
main concern is patchy fog in areas of the Kuskokwim Delta and
Alaska Peninsula due to light onshore flow. The chance of fog is
greatest during the second half of the nocturnal hours.

&&

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

A fairly benign weather pattern will continue across the
Bering/Aleutians. A weak area of low pressure will move into the
central Aleutians on Monday, then move southeastward back into the
North Pacific late Monday night into early Tuesday. This low will
bring rain and showers to the central Aleutians. Winds will remain
below gale force with no high seas expected. The biggest concern
is areas of fog and low stratus over the Bering Sea.

&&

.MARINE (Days 3 through 5 - Wednesday through Friday)...

High pressure moves into the eastern Bering with light winds
through Friday. A new low approaches the Western Aleutians on
Friday, with gusty winds less than gale force spreading into the
central Bering. Forecast confidence is good. A central Gulf low
exits through the southeastern Gulf Thursday.

&&

.LONG TERM FORECAST (Days 4 through 7: Thursday through
Sunday)...

The long term begins on Thursday with the upper-level low over
the central Gulf today (Sunday) continuing to track southeast
toward British Columbia. Upstream, an upper-level ridge amplifies
along the west coast of Alaska. This pattern will set up a drier
northerly flow across the southern mainland, with temperatures
likely climbing back above normal, especially for areas away from
the coast. While Thursday does look warmer, there may still be a
chance for clouds and showers from the Talkeetna Mountains east
across the Copper River Basin as a shortwave drops south, ejecting
from an upper-level low moving east along the Canadian Arctic.

On Friday, the ridge axis looks to shift slightly east, extending
across the interior of the state. This shift will likely help
strengthen the thermal trough, leading to even warmer
temperatures. The caveat to this will be whether or not there is
any influence from a potential second eastward propagating
shortwave. Right now, the GFS is more bullish with the EC
deepening the ridge. Either way, most of the energy with this
potential feature looks to remain along and north of the Alaska
Range, with any showers confined to the higher elevations of
Southcentral.

Model divergence grows by the weekend, but all keep some
semblance of the ridge over the region. The question centers on the
progression of a third shortwave from the west. The GFS and GEM
are again showing this feature mainly traversing the Alaska Range,
with an eventual push into the Copper River Basin by Sunday
morning. The EC depicts a stronger closed low dropping from the
Kuskokwim Delta to Kodiak Island by Sunday morning. In terms of
precipitation, the GFS and GEM hint at another round of showers
from the Talkeetna Mountains east by late Saturday. The EC,
though, extends the shower activity over Southwest Alaska. Bottom
line, the shift in the orientation of the longwave ridge/trough
pattern will yield conditions more typical of mid-July.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Gale Warning: 119 120.
FIRE WEATHER...NONE.

&&

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