Small Craft Advisory 816, NWS Anchorage, AK

963 
FZAK52 PAFC 282257
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
257 PM AKDT Sat Oct 28 2017

Coastal Waters Forecast for Southwest Alaska+Bristol Bay+The
Alaska Peninsula Waters and the Aleutian Islands up to 100 nm out.

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.

PKZ199-291145-
257 PM AKDT Sat Oct 28 2017
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...
A 1000 mb low 175 nm northwest of Dutch Harbor moves to 100 nm
northwest of Saint Paul at 1002 mb Sat night and dissipates Sun
morning. A 983 mb low 500 nm south of Adak moves to 240 nm 
southwest of Dutch Harbor at 974 mb Sun afternoon and then moves 
to 90 nm northwest of Cape Newenham at 1001 mb Mon afternoon.

$$

PKZ150-291145-
South of the AK Peninsula Sitkinak to Castle Cape-
257 PM AKDT Sat Oct 28 2017

...SMALL CRAFT ADVISORY THROUGH SUNDAY NIGHT...

.TONIGHT...E wind 30 kt. Seas 9 ft. Rain.
.SUN...SE wind 20 kt increasing to 30 kt in the afternoon. Seas
9 ft. Rain.
.SUN NIGHT...S wind 30 kt. Seas 12 ft.
.MON AND MON NIGHT...SW wind 35 kt. Seas 20 ft.
.TUE...W wind 20 kt. Seas 11 ft.
.WED THROUGH THU...Variable wind 10 kt. Seas 4 ft.

$$

PKZ155-291145-
South of the AK Peninsula Castle Cape to Cape Sarichef-
257 PM AKDT Sat Oct 28 2017

...STORM WARNING SUNDAY NIGHT...

.TONIGHT...SE wind 25 kt. Seas 10 ft. Rain.
.SUN...SE wind 35 kt. Seas 14 ft. Rain.
.SUN NIGHT...S wind 50 kt, Seas 18 ft building to 28 ft after
midnight. From the Shumagin Islands E, S wind 30 kt increasing to
40 kt after midnight, Seas 15 ft.
.MON...S wind 45 kt. Seas 28 ft.
.MON NIGHT...SW wind 35 kt. Seas 20 ft.
.TUE...W wind 20 kt. Seas 9 ft.
.WED THROUGH THU...E wind 15 kt. Seas 5 ft.

$$

PKZ160-291145-
Bristol Bay-
257 PM AKDT Sat Oct 28 2017

...SMALL CRAFT ADVISORY THROUGH SUNDAY NIGHT...

.TONIGHT...SE wind 25 kt. Seas 5 ft. Rain.
.SUN...E wind 25 kt. Seas 5 ft. Rain.
.SUN NIGHT...SE wind 30 kt. Seas 6 ft.
.MON...S wind 35 kt. Seas 9 ft.
.MON NIGHT...SW wind 30 kt. Seas 9 ft.
.TUE...N wind 15 kt. Seas 6 ft.
.WED THROUGH THU...NE wind 10 kt. Seas 3 ft.

$$

PKZ165-291145-
Port Heiden to Cape Sarichef-
257 PM AKDT Sat Oct 28 2017

...GALE WARNING SUNDAY AND SUNDAY NIGHT...

.TONIGHT...SE wind 25 kt. Seas 7 ft.
.SUN...E wind 35 kt. From Port Moller E, E wind 20 kt increasing
to 30 kt in the afternoon. Seas 7 ft.
.SUN NIGHT...SE wind 45 kt. From Port Moller E, SE wind 30 kt
becoming S 40 kt after midnight. Seas 11 ft.
.MON...S wind 45 kt. Seas 12 ft.
.MON NIGHT...SW wind 35 kt. Seas 10 ft.
.TUE...W wind 15 kt. Seas 5 ft.
.WED...Variable wind 10 kt. Seas 5 ft.
.THU...E wind 15 kt. Seas 5 ft.

$$

PKZ170-291145-
Cape Sarichef to Nikolski Bering Side-
257 PM AKDT Sat Oct 28 2017

...GALE WARNING SUNDAY AND SUNDAY NIGHT...

.TONIGHT...SE wind 25 kt. Seas 8 ft.
.SUN...E wind 35 kt. Seas 10 ft. Rain.
.SUN NIGHT...SE wind 45 kt. Seas 11 ft. Rain.
.MON...SW wind 40 kt. Seas 10 ft.
.MON NIGHT...W wind 25 kt. Seas 7 ft.
.TUE...SW wind 15 kt. Seas 6 ft.
.WED...E wind 15 kt. Seas 6 ft.
.THU...E wind 20 kt. Seas 6 ft.

$$

PKZ171-291145-
Unalaska Bay-
257 PM AKDT Sat Oct 28 2017

...GALE WARNING SUNDAY NIGHT...

.TONIGHT...SE wind 20 kt. Seas 3 ft. Rain.
.SUN...E wind 25 kt. Seas 4 ft. Rain.
.SUN NIGHT...S wind 35 kt. Seas 5 ft. Rain.
.MON...SW wind 30 kt. Seas 4 ft.
.MON NIGHT...SW wind 10 kt. Seas 2 ft.
.TUE...Variable wind less than 10 kt. Seas 3 ft.
.WED...E wind 10 kt. Seas 2 ft.
.THU...E wind 15 kt. Seas 2 ft.

$$

PKZ172-291145-
Cape Sarichef to Nikolski Pacific Side-
257 PM AKDT Sat Oct 28 2017

...STORM WARNING SUNDAY NIGHT...

.TONIGHT...SE wind 25 kt. Seas 12 ft.
.SUN...E wind 30 kt becoming SE 40 kt in the afternoon. Seas 16
ft. Rain.
.SUN NIGHT...S wind 50 kt. Seas 24 ft building to 31 ft after
midnight.
.MON...SW wind 45 kt. Seas 29 ft.
.MON NIGHT...SW wind 30 kt. Seas 15 ft.
.TUE...W wind 15 kt. Seas 7 ft.
.WED THROUGH THU...E wind 20 kt. Seas 7 ft.

$$

PKZ173-291145-
Nikloski to Seguam Island Bering Side-
257 PM AKDT Sat Oct 28 2017

...GALE WARNING SUNDAY...

.TONIGHT...E wind 20 kt. Seas 8 ft.
.SUN...NE wind 35 kt increasing to 45 kt in the afternoon. Seas
15 ft. Rain.
.SUN NIGHT...N wind 30 kt. Seas 17 ft.
.MON...NW wind 30 kt. Seas 16 ft.
.MON NIGHT...W wind 20 kt. Seas 11 ft.
.TUE...Variable wind 10 kt. Seas 7 ft.
.WED...E wind 15 kt. Seas 6 ft.
.THU...E wind 20 kt. Seas 6 ft.

$$

PKZ174-291145-
Nikolski to Seguam Island Pacific Side-
257 PM AKDT Sat Oct 28 2017

...GALE WARNING SUNDAY...

.TONIGHT...NE wind 20 kt increasing to 30 kt after midnight. Seas
12 ft.
.SUN...NE wind 35 kt becoming E 25 kt in the afternoon. Seas 14
ft. Rain.
.SUN NIGHT...W wind 30 kt. Seas 20 ft.
.MON...W wind 30 kt. Seas 16 ft.
.MON NIGHT...W wind 15 kt. Seas 10 ft.
.TUE...SE wind 15 kt. Seas 7 ft.
.WED THROUGH THU...E wind 20 kt. Seas 9 ft.

$$

PKZ175-291145-
Seguam Island to Adak Bering Side-
257 PM AKDT Sat Oct 28 2017

...STORM WARNING SUNDAY AND SUNDAY NIGHT...

.TONIGHT...N wind 30 kt. Seas 6 ft building to 10 ft after
midnight.
.SUN...N wind 40 kt increasing to 50 kt in the afternoon. Seas 15
ft building to 22 ft in the afternoon. Rain.
.SUN NIGHT...N wind 50 kt diminishing to 40 kt after midnight.
Seas 23 ft.
.MON...NW wind 30 kt. Seas 18 ft.
.MON NIGHT...SW wind 15 kt. Seas 11 ft.
.TUE...SE wind 20 kt. Seas 7 ft.
.WED THROUGH THU...E wind 15 kt. Seas 7 ft.

$$

PKZ176-291145-
Seguam Island to Adak Pacific Side-
257 PM AKDT Sat Oct 28 2017

...STORM WARNING SUNDAY...

.TONIGHT...N wind 30 kt. Seas 12 ft.
.SUN...N wind 50 kt. Seas 19 ft. Rain.
.SUN NIGHT...NW wind 45 kt diminishing to 35 kt after midnight.
Seas 19 ft.
.MON...NW wind 25 kt. Seas 12 ft.
.MON NIGHT...Variable wind 10 kt. Seas 6 ft.
.TUE...SE wind 20 kt. Seas 12 ft.
.WED...E wind 15 kt. Seas 12 ft.
.THU...E wind 20 kt. Seas 9 ft.

$$

PKZ177-291145-
Adak to Kiska-
257 PM AKDT Sat Oct 28 2017

...GALE WARNING THROUGH SUNDAY NIGHT...

.TONIGHT...N wind 35 kt. Seas 11 ft.
.SUN...N wind 45 kt. Seas 18 ft.
.SUN NIGHT...N wind 40 kt. Seas 19 ft.
.MON...NW wind 25 kt. Seas 14 ft.
.MON NIGHT...S wind 30 kt. Seas 9 ft.
.TUE...S wind 35 kt. Seas 19 ft.
.WED...SE wind 20 kt. Seas 13 ft.
.THU...E wind 15 kt. Seas 8 ft.

$$

PKZ178-291145-
Kiska to Attu-
257 PM AKDT Sat Oct 28 2017

...SMALL CRAFT ADVISORY THROUGH SUNDAY NIGHT...

.TONIGHT...N wind 30 kt. Seas 11 ft.
.SUN...N wind 30 kt. Seas 10 ft.
.SUN NIGHT...N wind 30 kt becoming NE 20 kt after midnight. Seas
10 ft.
.MON...SE wind 40 kt. Seas 12 ft.
.MON NIGHT...S wind 45 kt. Seas 26 ft.
.TUE...S wind 40 kt. Seas 26 ft.
.WED...S wind 20 kt. Seas 15 ft.
.THU...SE wind 15 kt. Seas 8 ft.

$$

PKZ179-291145-
Pribilof Islands Near Shore Waters-
257 PM AKDT Sat Oct 28 2017

...STORM WARNING SUNDAY NIGHT...

.TONIGHT...SE wind 25 kt becoming E 15 kt after midnight. Seas 8
ft. Rain.
.SUN...NE wind 25 kt increasing to 45 kt in the afternoon. Seas 7
ft building to 11 ft in the afternoon. Rain.
.SUN NIGHT...NE wind 50 kt diminishing to 25 kt after midnight.
Seas 13 ft. Rain.
.MON...N wind 25 kt. Seas 10 ft.
.MON NIGHT...NW wind 20 kt. Seas 9 ft.
.TUE...Variable wind 10 kt. Seas 6 ft.
.WED THROUGH THU...SE wind 15 kt. Seas 7 ft.

$$

PKZ180-291145-
Kuskokwim Delta and Etolin Strait-
257 PM AKDT Sat Oct 28 2017

...GALE WARNING SUNDAY NIGHT...

.TONIGHT...SE wind 25 kt. Seas 7 ft.
.SUN...E wind 20 kt increasing to 30 kt in the afternoon. Seas 7
ft.
.SUN NIGHT...E wind 40 kt. Seas 10 ft. Rain.
.MON...SE wind 40 kt. Seas 12 ft.
.MON NIGHT...NW wind 30 kt. Seas 10 ft.
.TUE...NE wind 15 kt. Seas 5 ft.
.WED THROUGH THU...E wind 10 kt. Seas 4 ft.

$$

PKZ181-291145-
North and West of Nunivak Island-
257 PM AKDT Sat Oct 28 2017

...GALE WARNING SUNDAY NIGHT...

.TONIGHT...E wind 15 kt. Seas 6 ft. Widespread rain showers.
.SUN...E wind 15 kt becoming NE 25 kt in the afternoon. Seas 6 ft.
.SUN NIGHT...NE wind 40 kt. Seas 10 ft. Rain.
.MON...NE wind 30 kt. Seas 9 ft.
.MON NIGHT...N wind 20 kt. Seas 6 ft.
.TUE...E wind 15 kt. Seas 5 ft.
.WED...SE wind 15 kt. Seas 5 ft.
.THU...Variable wind 10 kt. Seas 5 ft.

$$

PKZ185-291145-
Saint Matthew Island Waters-
257 PM AKDT Sat Oct 28 2017

...GALE WARNING SUNDAY NIGHT...

.TONIGHT...NE wind 30 kt. Seas 7 ft.
.SUN...NE wind 30 kt. Seas 8 ft.
.SUN NIGHT...NE wind 40 kt. Seas 12 ft.
.MON...N wind 35 kt. Seas 12 ft.
.MON NIGHT...NE wind 25 kt. Seas 9 ft.
.TUE...SE wind 25 kt. Seas 12 ft.
.WED...SE wind 20 kt. Seas 12 ft.
.THU...SE wind 15 kt. Seas 8 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
431 PM AKDT Fri Oct 27 2017

.ANALYSIS AND UPPER LEVELS...
A long-wave trough is centered over the Bering Sea, but extends
northeastward across all of Alaska. A short-wave is digging down
the back side of this trough across the northwest Pacific, causing
the upper jet to lift northward toward mainland Alaska. A series
of weak surface lows are embedded within the trough, with a triple
point and trailing cold front tracking eastward across the south-
central Bering and central Aleutians. A couple short-waves
downstream of this are tracking across Southwest and Southcentral
Alaska today bringing some light precip to the region. Most areas
have warmed enough to produce rain. However, the northern reaches
of the Susitna Valley and northeastern Copper River Basin remain
just cold enough to produce snow or mixed precip.

&&

.MODEL DISCUSSION...
Model spread continues to be fairly large with the two lows forming
over the north-central Pacific and moving up to the Bering Sea
this weekend. They do all come together with a single deep low
centered along the central Aleutians Sunday afternoon. Thus,
differences are focused right near the low center with good
agreement over the rest of the forecast area. With increasing
confidence in the depth of the low, we have trended stronger with
the winds.

&&

.AVIATION...
PANC...Conditions appear favorable for localized fog formation
tonight, with low level moisture left from this morning's rain,
mostly clear skies, and upper level high pressure building
overhead. However, a weak Turnagain wind will persist over the
northern Inlet. Thus, if fog does form it may stay away from the
terminal which is why the TAF is showing the VCFG in it.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
Weak high pressure moving into the area from the south will
provide for a break in the active weather that has moved through
the area over the past few days. This high pressure will bring
diminishing winds and clearing skies from west-east over the
course of this evening, leaving only the potential for patchy
fog/stratus to the Cook Inlet region as the primary forecast
concern in its wake. Saturday should be a fairly quiet and
pleasant day in most areas with partly sunny skies and slightly
above normal temperatures. However, this break in the weather is
not expected to persist much longer. Beginning Saturday evening,
gale force winds and rain is expected to move into Kodiak Island,
which will then spread into the North Gulf Coast on Sunday. This
will also bring strong cross barrier flow and gap winds along
Turnagain Arm, which should provide for enough downsloping over
Southcentral to prevent much of the rain from reaching the ground.
An active pattern with persistent southwest flow aloft will then
bring another weak low into the Western Gulf quickly behind the
first. This low is not only expected to bring another round of
rain throughout the Gulf Coast region, but with weaker cross-
barrier flow rainfall is expected to spread throughout most of
Southcentral to end the weekend.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
Showery conditions have tapered off briefly over the southern
Mainland as a shortwave ridge builds in behind the departing low.
However, precipitation is expected to pick back up early this
evening and persist through Saturday, with persistent widespread
southerly flow over the area and an upper level wave tracking
inland from the eastern Bering tonight. Unsettled weather will
continue through the weekend as a series of lows over the Bering
and North Pacific push north into the region bringing more
precipitation and above normal temperatures.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
The longwave pattern features an upper level trough stretching
over much of the Bering and western/central Aleutians, with a
frontal boundary at the surface tracking through the eastern
Aleutians/Bering and Alaska Peninsula tonight. A thermal ridge
will build over the eastern Aleutians/Bering this evening
resulting in temperatures warming above normal for late October. A
second system will enter the domain from the north Pacific
Saturday, not only keeping the warming trend alive and bringing
more rain to the area, but also bringing gusty winds to much of
the Aleutians Chain and Southern Bering through Saturday night.

Our focus then shifts to a much stronger north Pacific system,
deepening as it tracks northward into the central/eastern
Aleutians by Sunday afternoon. Model guidance is beginning to lock
in on a solution regarding this system, with a few differences
that effect the timing and strength of the impactful winds and
increased precipitation. Currently, the strongest core of winds
are expected to push into the coastal waters just south of Dutch
Harbor, and over the eastern/central Bering and Pribilof Islands
starting Sunday afternoon.

&&

.LONG TERM FORECAST (Days 3 through 7)...
The warmer pattern will continue through the weekend as broad
southwest flow remains focused over the southern mainland between
the Bering Sea trough and a stout northeast Pacific ridge. Friday
night into Saturday will also bring a break in precipitation for
Southcentral Alaska as high pressure briefly builds into the
central Gulf behind the departing system. Widespread rain will
then return to the area on Sunday as the next North Pacific low
moves into the eastern Bering accompanied by a front over the
Gulf. This will provide a reinforcing shot of warm air, with the
heaviest rain focused along the north Gulf coast through Monday
morning before that system also departs to the north.

There is lower confidence in how the pattern unfolds going into
the middle of the week as models continue to struggle with the
evolution of high pressure building into the Bering and western
Alaska behind the departing trough. The GFS/GEM both eventually
develop a closed high that drifts well to the north into the
Chukchi Sea. This would allow another trough to undercut the
ridge and move back into southern Alaska, keeping a chance of rain
in the forecast through the middle of the week. Meanwhile,
European guidance depicts a much more coherent blocking ridge
over the western mainland, which would keep most of the area dry
through much of the week in a weak offshore flow regime. Given
the uncertainty, the current forecast attempts to split the
difference in keeping a chance of rain over the southern mainland
into the middle of next week while gradually trending temperatures
down closer to seasonal normal values.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Gale 131 177.

&&

SYNOPSIS AND MODEL DISCUSSION...SEB
SOUTHCENTRAL ALASKA...DEK
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...TP
LONG TERM...JOE