Small Craft Advisory 554, NWS Anchorage, AK

377 
FZAK52 PAFC 182300
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
300 PM AKDT Wed Jul 18 2018

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.

PKZ199-191145-
300 PM AKDT Wed Jul 18 2018
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 1012 mb low over Dutch Harbor moves 200 nm southeast of Dutch
Harbor at 1014 mb Thu afternoon and then dissipates by Fri 
afternoon. A 1008 mb Kamchatka low enters the western Bering Thu 
afternoon and moves 230 nm north of Shemya Fri afternoon at 1005 
mb.

$$

PKZ150-191145-
South of the AK Peninsula Sitkinak to Castle Cape-
300 PM AKDT Wed Jul 18 2018

.TONIGHT...SE wind increasing to 20 kt by midnight. Seas 5 ft.
.THU...SE wind 20 kt. Seas 7 ft.
.THU NIGHT...E wind 20 kt. Seas 7 ft.
.FRI AND FRI NIGHT...SE wind 20 kt. Seas 7 ft.
.SAT...SE wind 20 kt. Seas 8 ft.
.SUN THROUGH MON...S wind 15 kt. Seas 7 ft.

$$

PKZ155-191145-
South of the AK Peninsula Castle Cape to Cape Sarichef-
300 PM AKDT Wed Jul 18 2018

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...SE wind 25 kt. Seas 8 ft. Rain.
.THU...E wind 20 kt. Seas 7 ft.
.THU NIGHT...E wind 15 kt. Seas 6 ft.
.FRI...E wind 15 kt. Seas 5 ft.
.FRI NIGHT...E wind 20 kt. Seas 6 ft.
.SAT...SE wind 20 kt. Seas 6 ft.
.SUN THROUGH MON...S wind 15 kt. Seas 6 ft.

$$

PKZ160-191145-
Bristol Bay-
300 PM AKDT Wed Jul 18 2018

.TONIGHT...SE wind 10 kt. Seas 2 ft.
.THU...SE wind 15 kt. Seas 3 ft.
.THU NIGHT...E wind 20 kt. Seas 3 ft.
.FRI AND FRI NIGHT...SE wind 20 kt. Seas 4 ft.
.SAT...SE wind 20 kt. Seas 4 ft.
.SUN THROUGH MON...SE wind 15 kt. Seas 3 ft.

$$

PKZ165-191145-
Port Heiden to Cape Sarichef-
300 PM AKDT Wed Jul 18 2018

.TONIGHT...SE wind 20 kt. Seas 4 ft.
.THU...E wind 20 kt. Seas 4 ft.
.THU NIGHT...E wind 20 kt. Seas 4 ft.
.FRI AND FRI NIGHT...SE wind 20 kt. Seas 3 ft.
.SAT...SE wind 20 kt. Seas 4 ft.
.SUN...SE wind 15 kt. Seas 4 ft.
.MON...Variable wind 10 kt. Seas 3 ft.

$$

PKZ170-191145-
Cape Sarichef to Nikolski Bering Side-
300 PM AKDT Wed Jul 18 2018

.TONIGHT...NE wind 15 kt. Seas 4 ft. Patchy fog.
.THU...NE wind 15 kt. Seas 4 ft. Patchy fog.
.THU NIGHT...NE wind 15 kt. Seas 3 ft.
.FRI...Variable wind 10 kt. Seas 2 ft.
.FRI NIGHT...SE wind 15 kt. Seas 3 ft.
.SAT...SE wind 15 kt. Seas 3 ft.
.SUN...Variable wind 10 kt. Seas 4 ft.
.MON...Variable wind 10 kt. Seas 3 ft.

$$

PKZ171-191145-
Unalaska Bay-
300 PM AKDT Wed Jul 18 2018

.TONIGHT...E wind 10 kt. Seas 2 ft. Patchy fog.
.THU...NE wind 10 kt. Seas 2 ft. Patchy fog.
.THU NIGHT...E wind 10 kt in the evening becoming variable less
than 10 kt. Seas 2 ft.
.FRI AND FRI NIGHT...SE wind 10 kt. Seas 2 ft.
.SAT...SE wind 10 kt. Seas 2 ft.
.SUN...Variable wind less than 10 kt. Seas 2 ft.
.MON...Variable wind less than 10 kt. Seas 2 ft.

$$

PKZ172-191145-
Cape Sarichef to Nikolski Pacific Side-
300 PM AKDT Wed Jul 18 2018

.TONIGHT...Variable wind 10 kt. Seas 5 ft. Patchy fog.
.THU...NE wind 15 kt. Seas 6 ft. Patchy fog.
.THU NIGHT...NE wind 10 kt. Seas 5 ft.
.FRI...Variable wind 10 kt. Seas 4 ft.
.FRI NIGHT...SE wind 15 kt. Seas 5 ft.
.SAT THROUGH SUN...Variable wind 10 kt. Seas 6 ft.
.MON...SW wind 15 kt. Seas 5 ft.

$$

PKZ173-191145-
Nikolski to Seguam Island Bering Side-
300 PM AKDT Wed Jul 18 2018

.TONIGHT...N wind 10 kt. Seas 3 ft. Patchy fog.
.THU...N wind 10 kt. Seas 4 ft. Patchy fog.
.THU NIGHT...Variable wind 10 kt. Seas 3 ft. Patchy fog.
.FRI AND FRI NIGHT...S wind 15 kt. Seas 4 ft.
.SAT THROUGH SUN...Variable wind 10 kt. Seas 3 ft.
.MON...Variable wind 10 kt. Seas 3 ft.

$$

PKZ174-191145-
Nikolski to Seguam Island Pacific Side-
300 PM AKDT Wed Jul 18 2018

.TONIGHT...NW wind 15 kt. Seas 6 ft. Patchy fog.
.THU...NW wind 15 kt. Seas 5 ft. Patchy fog.
.THU NIGHT...Variable wind 10 kt. Seas 5 ft. Patchy fog.
.FRI...Variable wind 10 kt. Seas 5 ft.
.FRI NIGHT...S wind 15 kt. Seas 5 ft.
.SAT THROUGH SUN...Variable wind 10 kt. Seas 5 ft.
.MON...SW wind 15 kt. Seas 5 ft.

$$

PKZ175-191145-
Seguam Island to Adak Bering Side-
300 PM AKDT Wed Jul 18 2018

.TONIGHT...NW wind 10 kt. Seas 3 ft.
.THU...Variable wind 10 kt. Seas 2 ft. Patchy fog.
.THU NIGHT...SE wind 15 kt. Seas 4 ft. Patchy fog. Rain.
.FRI...S wind 15 kt. Seas 4 ft.
.FRI NIGHT...Variable wind 10 kt. Seas 3 ft.
.SAT...Variable wind 10 kt. Seas 3 ft.
.SUN THROUGH MON...Variable wind 10 kt. Seas 3 ft.

$$

PKZ176-191145-
Seguam Island to Adak Pacific Side-
300 PM AKDT Wed Jul 18 2018

.TONIGHT...NW wind 15 kt. Seas 6 ft.
.THU...NW wind 10 kt. Seas 5 ft. Patchy fog.
.THU NIGHT...Variable wind 10 kt becoming SW 20 kt after midnight.
Seas 5 ft. Patchy fog. Rain.
.FRI...SW wind 20 kt. Seas 7 ft.
.FRI NIGHT...SW wind 15 kt. Seas 7 ft.
.SAT THROUGH MON...SW wind 15 kt. Seas 6 ft.

$$

PKZ177-191145-
Adak to Kiska-
300 PM AKDT Wed Jul 18 2018

...SMALL CRAFT ADVISORY THURSDAY NIGHT...

.TONIGHT...SW wind 15 kt. Seas 6 ft.
.THU...SW wind 20 kt. Seas 7 ft. Rain.
.THU NIGHT...SW wind 25 kt. Seas 8 ft. Rain.
.FRI...SW wind 20 kt. Seas 8 ft.
.FRI NIGHT...W wind 15 kt. Seas 7 ft.
.SAT THROUGH MON...SW wind 15 kt. Seas 6 ft.

$$

PKZ178-191145-
Kiska to Attu-
300 PM AKDT Wed Jul 18 2018

...SMALL CRAFT ADVISORY THROUGH THURSDAY NIGHT...

.TONIGHT...S wind 25 kt. Seas 7 ft.
.THU...SW wind 25 kt. Seas 9 ft.
.THU NIGHT...SW wind 25 kt decreasing to 15 kt by midnight. Seas 9 
ft.
.FRI AND FRI NIGHT...W wind 15 kt. Seas 8 ft.
.SAT...SW wind 15 kt. Seas 6 ft.
.SUN THROUGH MON...S wind 15 kt. Seas 5 ft.

$$

PKZ179-191145-
Pribilof Islands Near Shore Waters-
300 PM AKDT Wed Jul 18 2018

.TONIGHT...E wind 10 kt. Seas 4 ft. Patchy fog.
.THU...E wind 10 kt. Seas 4 ft. Patchy fog.
.THU NIGHT...E wind 10 kt. Seas 3 ft. Patchy fog.
.FRI AND FRI NIGHT...SE wind 15 kt. Seas 3 ft.
.SAT...SE wind 15 kt. Seas 4 ft.
.SUN THROUGH MON...Variable wind 10 kt. Seas 4 ft.

$$

PKZ180-191145-
Kuskokwim Delta and Etolin Strait-
300 PM AKDT Wed Jul 18 2018

.TONIGHT...SE wind 10 kt. Seas 3 ft. Patchy fog.
.THU...E wind 20 kt. Seas 3 ft. Patchy fog.
.THU NIGHT...E wind 20 kt. Seas 4 ft.
.FRI AND FRI NIGHT...SE wind 20 kt. Seas 4 ft.
.SAT...SE wind 20 kt. Seas 5 ft.
.SUN THROUGH MON...SE wind 15 kt. Seas 4 ft.

$$

PKZ181-191145-
North and West of Nunivak Island-
300 PM AKDT Wed Jul 18 2018

.TONIGHT...SE wind 15 kt. Seas 3 ft. Patchy fog.
.THU...SE wind 10 kt. Seas 3 ft. Patchy fog.
.THU NIGHT...Variable wind less than 10 kt. Seas 2 ft.
.FRI AND FRI NIGHT...E wind 20 kt. Seas 4 ft.
.SAT THROUGH SUN...SE wind 15 kt. Seas 3 ft.
.MON...Variable wind 10 kt. Seas 3 ft.

$$

PKZ185-191145-
Saint Matthew Island Waters-
300 PM AKDT Wed Jul 18 2018

.TONIGHT...S wind 15 kt. Seas 5 ft. Patchy fog.
.THU...S wind 15 kt. Seas 5 ft. Patchy fog.
.THU NIGHT...SE wind 15 kt. Seas 3 ft.
.FRI...SE wind 15 kt. Seas 4 ft.
.FRI NIGHT...E wind 20 kt. Seas 5 ft.
.SAT...SE wind 20 kt. Seas 5 ft.
.SUN THROUGH MON...Variable wind 10 kt. Seas 4 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
422 PM AKDT Tue Jul 17 2018

.ANALYSIS AND UPPER LEVELS...
An upper long wave trough evident on water vapor is moving
southeast across Southcentral Alaska this afternoon. Showers have
started to develop over the Susitna Valley, Talkeetna Mountains,
and Copper River Basin. These areas will see some isolated
thunderstorms. Subsidence under a building upper ridge over the
eastern/northern Bering Sea is producing widespread stratus and
patchy fog across much of the Bering Sea and portions of the
Kuskokwim Dela and Bristol Bay. A weakening low center over the
southern Bering Sea and leading front, extending to the eastern
Aleutians is producing light rain, stratus, and fog across the
Aleutians.

&&

.MODEL DISCUSSION...
Models in the east are in generally good synoptic agreement.
However, there are some significant model differences which
develop with a front and weak low which moves to the western
Aleutians Wednesday and Thursday. Otherwise, fog and stratus will
be the main challenges out west and warming temps and drying
conditions in the east.

&&

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

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3)...
(Tonight through Friday)
Showers and isolated thunderstorms have once again developed this
afternoon, as daytime heating has allowed some weak instability
to develop per the latest RAP analysis showing lifted indices in
the -1 to -4 range, with 100 to 400 J/kg of SBCAPE across the
Mat-Su Valleys, Copper River Basin, and Kenai Peninsula. The most
prominent storm was located west of the lower portions of the
Little Susitna River, with this storm having remained fairly
organized and likely producing some small hail. However, that's
been about it thus far concerning any convection.

This convection has been aided by a second short-wave trough that
followed yesterday's disturbance, with it brushing mainly the
northern and eastern portion of the area. This increased
cooling/ascent may allow for some uptick in precipitation coverage
over the next few hours, before precipitation diminishes
overnight as subsidence behind the departing wave takes hold.

Otherwise, the main weather feature will be a short-wave ridge of
high pressure building across Southcentral, with some difference
in the models regarding how strong of a ridge develops. The GFS
current forecasts 500 mb heights topping out near 576 dkm, where
as the ECMWF is more robust with these heights approaching 580
dkm. The subsequent difference shows up in the 850mb thermal
fields with temps in the 10 to 14 deg. C range. What this means
for us is our current forecast highs of the upper 60s to upper 70s
may need to be increased somewhat if the higher heights/warmer
850 mb temps verify in later model runs.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 3)...
Ridging will remain over southwest Alaska into Friday as its axis
slowly shifts east. This setup should keep rain away from the area
and allow for some breaks in the clouds. Tonight, fog will form
along the coast and advect into southwest Alaska from weak onshore
flow spreading through many coastal locations and some areas
further inland. The fog will then dissipate Wednesday morning.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 through 3)...
The low in the southern Bering will drift slowly to the southeast
moving across the eastern Aleutians tonight. It will bring more
rain to the islands in the area through much of Wednesday until it
tracks further into the North Pacific. However, southerly flow
for the Alaska Peninsula will bring continued rain for much of the
week. Further out west another system is moving towards the
western Aleutians. Its front will move in Wednesday and then
slowly push east through the rest of the week making it to the
central Aleutians Thursday night.

&&

.LONG TERM FORECAST (Days 3 through 7: Friday through Tuesday)...
The entirety of southern mainland Alaska will be under the
influence of broad upper level ridging on Friday, which will
support sunny skies and very warm temperatures, especially across
Southcentral. Near the coast, fog and low stratus will be a
concern during the overnight hours. With Southwest Alaska being on
the western side of the ridge, the southerly flow and troughing
out over the Bering will support more cloud cover, especially for
coastal locations.

On Saturday, the ridge axis slides eastward over the Copper River
Basin, allowing for more cloud cover and cooler temperatures to
move into nearly all of Southwest Alaska, while most of
Southcentral continues baking with very summer-like temperatures.
The exceptions will be Kodiak Island and the coastal areas
impacted by clouds and fog.

Sunday will be the transition day for Southcentral west of the
Talkeetna and Chugach Mountains. The ridge will continue moving
eastward into Canada, allowing for wet weather associated with an
advancing area of low pressure to move into all of Southwest
Alaska, Kodiak, and the southern Kenai Peninsula. For now it looks
like most areas from Kenai northward will remain dry, but
significant cloud cover should temper afternoon highs as compared
with previous days. The Copper Basin will remain very warm.

Monday and Tuesday now look to be significantly wetter as compared
with previous model runs for much of Southcentral, though rainfall
coverage will diminish as one goes eastward. The upper level low
responsible for the southerly push causing the wet weather will
move into the eastern Bering.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...None.

&&

SYNOPSIS AND MODEL DISCUSSION...RC
SOUTHCENTRAL ALASKA...PD
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...DK
LONG TERM...JW