Small Craft Advisory 917, NWS Anchorage, AK

Issued

Dec 1, 2017, 3:13 PM AKST (00:13 UTC)

Expired

Dec 2, 2017, 3:45 AM AKST

In force

13 hr

Issued by

NWS Anchorage, AK

605 
FZAK52 PAFC 020013
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
313 PM AKST Fri Dec 1 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.

PKZ199-021245-
313 PM AKST Fri Dec 1 2017
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...
A front over the eastern Bering will dissipate through Sat 
morning. A 979 mb North Pacific low will move to 300 nm southeast 
of Dutch Harbor by Sun morning then it will move to 120 nm 
southeast of Sand Point at 965 mb by Sun afternoon.

$$

PKZ150-021245-
South of the AK Peninsula Sitkinak to Castle Cape-
313 PM AKST Fri Dec 1 2017

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

.TONIGHT...S wind 30 kt. Seas 12 ft. Rain.
.SAT...SW wind 20 kt in the morning becoming variable 10 kt. Seas
11 ft.
.SAT NIGHT...E wind 20 kt increasing to 30 kt after midnight. Seas
10 ft. Rain.
.SUN...SE wind 35 kt. Seas 19 ft.
.SUN NIGHT...SW wind 45 kt. Seas 24 ft.
.MON...SW wind 40 kt. Seas 23 ft.
.TUE...S wind 15 kt. Seas 12 ft.
.WED...SE wind 15 kt. Seas 7 ft.

$$

PKZ155-021245-
South of the AK Peninsula Castle Cape to Cape Sarichef-
313 PM AKST Fri Dec 1 2017

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

.TONIGHT...SW wind 30 kt. Seas 15 ft.
.SAT...SW wind 20 kt in the morning becoming variable 10 kt. Seas
12 ft.
.SAT NIGHT...NE wind 30 kt. Seas 11 ft. Rain.
.SUN...N wind 45 kt. Seas 18 ft.
.SUN NIGHT...W wind 45 kt. Seas 17 ft.
.MON...SW wind 30 kt. Seas 17 ft.
.TUE...SW wind 15 kt. Seas 10 ft.
.WED...Variable wind 10 kt. Seas 7 ft.

$$

PKZ160-021245-
Bristol Bay-
313 PM AKST Fri Dec 1 2017

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

.TONIGHT...S wind 30 kt becoming SW 20 kt after midnight. Seas 9
ft. Patchy fog. Rain.
.SAT...SW wind 20 kt. Seas 7 ft.
.SAT NIGHT...SE wind 15 kt becoming NE 30 kt after midnight. Seas
7 ft. Patchy fog.
.SUN...NE wind 35 kt. Seas 9 ft.
.SUN NIGHT...SE wind 40 kt. Seas 16 ft.
.MON...S wind 40 kt. Seas 13 ft.
.TUE THROUGH WED...E wind 15 kt. Seas 7 ft.

$$

PKZ165-021245-
Port Heiden to Cape Sarichef-
313 PM AKST Fri Dec 1 2017

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

.TONIGHT...SW wind 25 kt. Seas 12 ft.
.SAT...SW wind 25 kt. Seas 14 ft.
.SAT NIGHT...E wind 15 kt becoming NE 30 kt after midnight. Seas
12 ft. Snow showers.
.SUN...N wind 45 kt. Seas 17 ft.
.SUN NIGHT...W wind 40 kt. Seas 17 ft.
.MON...SW wind 35 kt. Seas 16 ft.
.TUE...SW wind 15 kt. Seas 11 ft.
.WED...Variable wind 10 kt. Seas 6 ft.

$$

PKZ170-021245-
Cape Sarichef to Nikolski Bering Side-
313 PM AKST Fri Dec 1 2017

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

.TONIGHT...SW wind 30 kt. Seas 17 ft.
.SAT...SW wind 25 kt. Seas 17 ft.
.SAT NIGHT...Variable wind 10 kt becoming N 20 kt after midnight.
Seas 13 ft.
.SUN AND SUN NIGHT...W wind 30 kt. Seas 12 ft.
.MON...W wind 30 kt. Seas 14 ft.
.TUE...W wind 20 kt. Seas 13 ft.
.WED...Variable wind 10 kt. Seas 7 ft.

$$

PKZ171-021245-
Unalaska Bay-
313 PM AKST Fri Dec 1 2017

.TONIGHT...SW wind 20 kt. Seas 3 ft.
.SAT...SW wind 15 kt becoming S in the afternoon. Seas 2 ft.
.SAT NIGHT...NE wind 10 kt becoming N 20 kt after midnight. Seas
3 ft building to 5 ft after midnight. Rain showers and snow showers.
.SUN...NW wind 25 kt. Seas 9 ft.
.SUN NIGHT...W wind 30 kt. Seas 9 ft.
.MON...W wind 25 kt. Seas 3 ft.
.TUE...W wind 10 kt. Seas 3 ft.
.WED...Variable wind less than 10 kt. Seas 3 ft.

$$

PKZ172-021245-
Cape Sarichef to Nikolski Pacific Side-
313 PM AKST Fri Dec 1 2017

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

.TONIGHT...SW wind 30 kt. Seas 15 ft.
.SAT...SW wind 20 kt in the morning becoming variable 10 kt. Seas
14 ft.
.SAT NIGHT...NE wind 20 kt becoming N 30 kt after midnight. Seas
10 ft. Rain showers.
.SUN...NW wind 40 kt. Seas 14 ft.
.SUN NIGHT...W wind 35 kt. Seas 12 ft.
.MON...W wind 25 kt. Seas 11 ft.
.TUE...NW wind 20 kt. Seas 11 ft.
.WED...Variable wind 10 kt. Seas 7 ft.

$$

PKZ173-021245-
Nikloski to Seguam Island Bering Side-
313 PM AKST Fri Dec 1 2017

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

.TONIGHT...SW wind 30 kt. Seas 19 ft.
.SAT...SW wind 25 kt. Seas 17 ft.
.SAT NIGHT...W wind 20 kt. Seas 13 ft.
.SUN AND SUN NIGHT...W wind 20 kt. Seas 10 ft.
.MON...W wind 25 kt. Seas 13 ft.
.TUE...NW wind 20 kt. Seas 12 ft.
.WED...W wind 15 kt. Seas 8 ft.

$$

PKZ174-021245-
Nikolski to Seguam Island Pacific Side-
313 PM AKST Fri Dec 1 2017

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

.TONIGHT...SW wind 30 kt. Seas 19 ft.
.SAT...SW wind 25 kt becoming W 15 kt in the afternoon. Seas 18
ft.
.SAT NIGHT...NW wind 20 kt. Seas 13 ft.
.SUN AND SUN NIGHT...W wind 25 kt. Seas 12 ft.
.MON...W wind 25 kt. Seas 15 ft.
.TUE...NW wind 20 kt. Seas 14 ft.
.WED...W wind 15 kt. Seas 9 ft.

$$

PKZ175-021245-
Seguam Island to Adak Bering Side-
313 PM AKST Fri Dec 1 2017

...GALE WARNING TONIGHT...

.TONIGHT...SW wind 35 kt. Seas 20 ft.
.SAT...SW wind 30 kt. Seas 18 ft.
.SAT NIGHT...W wind 20 kt. Seas 13 ft.
.SUN AND SUN NIGHT...W wind 20 kt. Seas 11 ft.
.MON THROUGH TUE...NW wind 25 kt. Seas 12 ft.
.WED...W wind 15 kt. Seas 9 ft.

$$

PKZ176-021245-
Seguam Island to Adak Pacific Side-
313 PM AKST Fri Dec 1 2017

...GALE WARNING TONIGHT...

.TONIGHT...SW wind 35 kt. Seas 24 ft. Rain showers and snow
showers.
.SAT...SW wind 25 kt. Seas 20 ft.
.SAT NIGHT...W wind 20 kt. Seas 16 ft.
.SUN...W wind 25 kt. Seas 12 ft.
.SUN NIGHT...W wind 25 kt. Seas 16 ft.
.MON THROUGH TUE...NW wind 25 kt. Seas 15 ft.
.WED...W wind 15 kt. Seas 8 ft.

$$

PKZ177-021245-
Adak to Kiska-
313 PM AKST Fri Dec 1 2017

...GALE WARNING TONIGHT...

.TONIGHT...SW wind 40 kt. Seas 27 ft. Rain showers with snow
showers.
.SAT...SW wind 30 kt. Seas 23 ft. Snow showers and rain showers.
.SAT NIGHT...W wind 25 kt. Seas 19 ft. Snow showers.
.SUN...W wind 30 kt. Seas 16 ft.
.SUN NIGHT...W wind 25 kt. Seas 18 ft.
.MON...W wind 25 kt. Seas 16 ft.
.TUE...W wind 25 kt. Seas 12 ft.
.WED...SW wind 15 kt. Seas 8 ft.

$$

PKZ178-021245-
Kiska to Attu-
313 PM AKST Fri Dec 1 2017

...GALE WARNING THROUGH SATURDAY...

.TONIGHT...W wind 40 kt. Seas 30 ft. Snow showers and rain
showers.
.SAT...W wind 35 kt. Seas 25 ft. Snow showers.
.SAT NIGHT...W wind 30 kt. Seas 20 ft. Snow showers.
.SUN...W wind 30 kt. Seas 19 ft.
.SUN NIGHT...W wind 25 kt. Seas 18 ft.
.MON THROUGH TUE...W wind 25 kt. Seas 14 ft.
.WED...SW wind 15 kt. Seas 8 ft.

$$

PKZ179-021245-
Pribilof Islands Near Shore Waters-
313 PM AKST Fri Dec 1 2017

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

.TONIGHT...SW wind 30 kt. Seas 18 ft. Rain showers with snow
showers.
.SAT...SW wind 25 kt. Seas 17 ft.
.SAT NIGHT...SW wind 20 kt in the evening becoming variable 10 kt.
Seas 15 ft.
.SUN...N wind 15 kt. Seas 10 ft.
.SUN NIGHT...NW wind 25 kt. Seas 11 ft.
.MON...W wind 25 kt. Seas 14 ft.
.TUE...W wind 15 kt. Seas 13 ft.
.WED...Variable wind 10 kt. Seas 7 ft.

$$

PKZ180-021245-
Kuskokwim Delta and Etolin Strait-
313 PM AKST Fri Dec 1 2017

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

.TONIGHT...SW wind 25 kt. Seas 10 ft.
.SAT...SW wind 25 kt. Seas 10 ft.
.SAT NIGHT...S wind 15 kt becoming SE 25 kt after midnight. Seas
9 ft.
.SUN...NE wind 30 kt. Seas 10 ft.
.SUN NIGHT...N wind 35 kt. Seas 14 ft.
.MON...SW wind 40 kt. Seas 13 ft.
.TUE...S wind 15 kt. Seas 9 ft.
.WED...SE wind 10 kt. Seas 6 ft.

$$

PKZ181-021245-
North and West of Nunivak Island-
313 PM AKST Fri Dec 1 2017

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

.TONIGHT...S wind 25 kt. Seas 10 ft.
.SAT...S wind 20 kt. Seas 10 ft.
.SAT NIGHT...S wind 20 kt. Seas 10 ft.
.SUN...E wind 20 kt. Seas 8 ft.
.SUN NIGHT...NE wind 25 kt. Seas 8 ft.
.MON...E wind 30 kt. Seas 9 ft.
.TUE THROUGH WED...SE wind 15 kt. Seas 6 ft.

$$

PKZ185-021245-
Saint Matthew Island Waters-
313 PM AKST Fri Dec 1 2017

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

.TONIGHT...S wind 25 kt. Seas 17 ft. Rain showers and snow
showers.
.SAT...S wind 25 kt. Seas 17 ft.
.SAT NIGHT...S wind 20 kt. Seas 16 ft.
.SUN...SE wind 15 kt. Seas 12 ft.
.SUN NIGHT...NE wind 25 kt. Seas 10 ft.
.MON...N wind 25 kt. Seas 11 ft.
.TUE...N wind 15 kt. Seas 10 ft.
.WED...E wind 15 kt. Seas 7 ft.

$$

NWS Anchorage, AK wrote its last area forecast discussion before this small craft advisory went out at Dec 1, 4:37 AM AKST, 10 hours 36 minutes earlier.

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
437 AM AKST Fri Dec 1 2017

.ANALYSIS AND UPPER LEVELS...
A transient upper level ridge is building over western Alaska this
morning as a low south of the Gulf continues to weaken and pull to
the southeast, with a broad longwave trough extending from the
Alcan border region into the eastern Gulf. This pattern is
promoting fairly benign conditions across most of the southern
mainland as showers continue to taper off over the Gulf, with
areas of low stratus and some patchy fog developing in various
locations from the Copper River Basin to Southwest AK. Meanwhile,
a gale force front extending from a deep Kamchatka low is moving
through the eastern Bering accompanied by widespread rain, and is
just beginning to impact the Kuskokwim Delta coast with mixed
precipitation as it tracks eastward towards the mainland.

&&

.MODEL DISCUSSION...
Models show good agreement into the weekend as the ridge quickly
traverses the mainland from west to east, allowing the front and a
trailing shortwave trough to move through the Cook Inlet region
and the Susitna Valley and bring another shot of precipitation to
Southcentral AK on Saturday. Forecast confidence then begins to
decrease once again by Saturday night as a deep North Pacific low
approaches the Alaska Peninsula from the south. Models have
actually backtracked somewhat on their previous agreement with the
arrival of the 00z suite, with the GFS solution now faster and
much farther north than the other guidance whereas the NAM depicts
an overall weaker system than the others. Despite this, was still
able to utilize the NAM for the low position as it represents a
middle ground approach among the guidance and maintains good
continuity from the previous forecast.

&&

.AVIATION...
PANC...Patchy fog over upper Cook Inlet will keep a threat for
IFR/LIFR conditions at the terminal through late morning. VFR
conditions and light winds will then persist through Friday night
before a front moves into the region Saturday morning and drops
ceilings below 5000 ft. Strong downslope flow is expected to keep
showers away from the terminal, though some may still develop in
the vicinity. Southeast winds will develop off of Turnagain Arm
after 16z as the down inlet pressure gradient weakens.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
Today is the break between systems across Southcentral as the next
front will begin to move into the area tonight. There is a lot of
warm air with this system which will switch the precipitation type
to rain across most of the coastal areas. Inland there is still
enough cold air to remain snow especially in the Susitna Valley
where there is a Winter Weather Advisory for Saturday. There is
some uncertainty as to how early the snow will start tomorrow
morning but the 6 AM start time looks reasonable at this time but
may need some adjusting as it gets nearer.
Anchorage and the Matanuska Valley may get a quick snow early
tomorrow morning, but the Southeast winds and associated
downsloping will probably cut it off quickly. However, there is
still a chance that the upper level southerly flow will tilt
enough southwestward to help diminish the low level southeast flow
which could then bring in a few inches to Anchorage. This scenario
looks less likely right now so stuck with the chance of snow for
Saturday for the Anchorage and Palmer-Wasilla areas.
On the western Kenai Peninsula, any snowfall Homer experiences
will quickly change to rain Saturday morning. Kenai is the area
that has a trickier precipitation-type forecast as is it close to
the rain-snow line. At this time, it is looking like Kenai and
Soldotna will remain all snow with the transition to rain being
south of there.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
A front continues to slowly push eastward into the Southwest
coast this morning through Saturday, bringing precipitation across
the region along with some warmer southerly flow. The main
challenge regarding this system is precipitation type along the
coastal regions of the western coast, as the warm air mass nudges
inland. Overall the precipitation type should remain snow over
much of the southwest Mainland. However, the western coast is
expected to start off as snow and change over to rain or a
rain/snow mix as early as late Friday morning for the Kuskokwim
Delta, and Friday afternoon for the Bristol Bay area. By Saturday
morning the lingering showers over the area is expected to
transition back to snow, with the exception of mixed precipitation
continuing through Saturday night south of King Salmon as the
next system approaches from the North Pacific.

Models continue to struggle with the placement and timing details
of this upcoming system, but have started to come into some
agreement with the 06Z model runs. They are honing in on a
deepening low tracking across the Alaska Peninsula Sunday, with a
strong front ahead of it bringing another round of gusty winds and
precipitation to the southwest Mainland on Sunday.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
Low pressure over the far western Bering pushes a front into the
western coast this morning, with a mix of rain and snow showers
expected in its wake. Gusty winds will continue to shift to the
southwest behind the front and will remain the predominant flow
over much of the Bering through Saturday, as the low anchors
itself over the far western Bering. However, the strong flow
diminishes as the western Bering low fills on Saturday and the
next low begins to track into the Alaska Peninsula from the North
Pacific Saturday night. Snow showers are expected to prevail over
the western half of the Bering and Aleutians through Sunday as the
western Bering low slowly weakens and continues to feed in colder
air from the west. Whereas the eastern half of the Bering and
Aleutians will start off as rain with the current system over
them. Precipitation will slowly transition to a rain/snow mix
(from northwest to southeast) overnight tonight, then start
transitioning to mostly snow by Sunday morning as the colder air
from the west begins to push further eastward over the area.

&&

.LONG TERM FORECAST (Saturday through Wednesday)...
Sunday will see the exit of a weak system from Southcentral
Alaska. On it's heels is another storm system that most of the
models have really locked in on. A strong 170+ kt jet across the
northern Pacific will eject a rather potent shortwave about 500
miles South of Dutch. This storm system will be the primary focus
through the end of the weekend and into the early week. This low
will quickly deepen and track to the north, crossing the western
periphery of Kodiak Island. Guidance has been consistent with
bringing a strong front across the the Pacific and into the Gulf
of Alaska. As the front moves across the coast it will bring quite
the river of moisture and warmth with it. Guidance is also
hinting at the fact that Turnagain Arm and high elevations will
see a strong wind event into Monday. It's looking to not be an
event impacting much of the Anchorage Bowl, as winds exiting the
Arm should turn and head south down the inlet. With the strong
front will come strong cross barrier flow over much of
Southcentral. The winds will warm and dry the lower
atmosphere...leading to warmer than freezing temperatures and the
lack of precipitation across much of the usual downslope regions.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Weather Advisory 145
MARINE...Gale Warning 155 165 170 172 173 175 176 177 178 180 181
					  411 413 414

&&

SYNOPSIS AND MODEL DISCUSSION...CB
SOUTHCENTRAL ALASKA...EZ
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...TP
LONG TERM...SS

Small Craft Advisories in Alaska, 2017Every small craft advisory in 2017

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text.