Small Craft Advisory 608, NWS Anchorage, AK

906 
FZAK51 PAFC 131153
CWFAER

Coastal Waters Forecast
National Weather Service Anchorage Alaska
353 AM AKDT Thu Aug 13 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.

PKZ197-140100-
353 AM AKDT Thu Aug 13 2020
.SYNOPSIS FOR THE NORTH GULF COAST+KODIAK ISLAND WATERS+
COOK INLET...

High pressure lingers over the North Gulf Coast through Thu
afternoon. A front with a series of weak lows moves across the 
Southern Gulf Thu afternoon through Fri afternoon. A 1006 mb low 130 
nm south of Sand Point Thu night moves into the North Pacific Fri 
afternoon.

$$

PKZ119-140100-
Cape Suckling to Cape Cleare-
353 AM AKDT Thu Aug 13 2020

.TODAY...Variable wind 10 kt. Seas 4 ft.
.TONIGHT...Variable wind 10 kt. Seas 3 ft.
.FRI...Variable wind 10 kt. Seas 4 ft.
.FRI NIGHT...NW wind 15 kt. Seas 5 ft.
.SAT...N wind 15 kt. Seas 6 ft.
.SUN THROUGH MON...E wind 15 kt. Seas 5 ft.

$$

PKZ120-140100-
Cape Cleare to Gore Point-
353 AM AKDT Thu Aug 13 2020

.TODAY...Variable wind 10 kt. Seas 4 ft.
.TONIGHT...Variable wind 10 kt. Seas subsiding to 2 ft.
.FRI...Variable wind 10 kt. Seas 4 ft.
.FRI NIGHT...N wind 15 kt. Seas 5 ft.
.SAT...N wind 15 kt. Seas 5 ft.
.SUN THROUGH MON...E wind 15 kt. Seas 5 ft.

$$

PKZ121-140100-
Resurrection Bay-
353 AM AKDT Thu Aug 13 2020

.TODAY...N wind 10 kt becoming S in the afternoon. Seas 2 ft.
.TONIGHT...S wind 10 kt becoming N after midnight. Seas 2 ft.
.FRI...N wind 10 kt becoming variable in the afternoon. Seas 2 ft.
.FRI NIGHT...N wind 20 kt. Seas 4 ft.
.SAT...N wind 20 kt. Seas 4 ft.
.SUN...Variable wind less than 10 kt. Seas 2 ft.
.MON...S wind 10 kt. Seas 2 ft.

$$

PKZ125-140100-
Prince William Sound-
353 AM AKDT Thu Aug 13 2020

.TODAY...Variable wind less than 10 kt. Seas 2 ft.
.TONIGHT...Variable wind less than 10 kt. Seas 2 ft.
.FRI...Variable wind less than 10 kt becoming W 10 kt in the
afternoon. Seas 2 ft.
.FRI NIGHT...NW wind 15 kt. Seas 2 ft.
.SAT...N wind 15 kt. Seas 3 ft.
.SUN THROUGH MON...E wind 10 kt. Seas 2 ft.

$$

PKZ126-140100-
Port Valdez-
353 AM AKDT Thu Aug 13 2020

.TODAY...Variable wind less than 10 kt. Seas 2 ft.
.TONIGHT...Variable wind less than 10 kt becoming NE 10 kt after
midnight. Seas 2 ft.
.FRI...NE wind 15 kt. Seas 3 ft.
.FRI NIGHT...NE wind 20 kt. Seas 4 ft.
.SAT...NE wind 25 kt. Seas 5 ft.
.SUN...NE wind 10 kt. Seas 2 ft.
.MON...E wind 10 kt. Seas 2 ft.

$$

PKZ127-140100-
Valdez Narrows-
353 AM AKDT Thu Aug 13 2020

.TODAY...Variable wind less than 10 kt. Seas 2 ft.
.TONIGHT...Variable wind less than 10 kt. Seas 2 ft.
.FRI...NE wind 15 kt. Seas 3 ft.
.FRI NIGHT...NE wind 30 kt. Seas 3 ft.
.SAT...NE wind 30 kt. Seas 3 ft.
.SUN...NE wind 15 kt. Seas 3 ft.
.MON...Variable wind 10 kt. Seas 2 ft.

$$

PKZ128-140100-
Valdez Arm-
353 AM AKDT Thu Aug 13 2020

.TODAY...Variable wind less than 10 kt. Seas 2 ft.
.TONIGHT...Variable wind less than 10 kt. Seas 2 ft.
.FRI...Variable wind less than 10 kt. Seas 2 ft.
.FRI NIGHT...NE wind 25 kt. Seas 5 ft.
.SAT...NE wind 25 kt. Seas 5 ft.
.SUN...NE wind 10 kt. Seas 2 ft.
.MON...Variable wind 10 kt. Seas 2 ft.

$$

PKZ129-140100-
Passage Canal-
353 AM AKDT Thu Aug 13 2020

.TODAY...W wind 10 kt. Seas 2 ft.
.TONIGHT...E wind 10 kt becoming S after midnight. Seas 2 ft.
.FRI...W wind 10 kt. Seas 2 ft.
.FRI NIGHT...W wind 15 kt. Seas 2 ft.
.SAT...W wind 20 kt. Seas 3 ft.
.SUN...Variable wind less than 10 kt. Seas 2 ft.
.MON...E wind 10 kt. Seas 2 ft.

$$

PKZ130-140100-
West of Barren Islands including Kamishak Bay-
353 AM AKDT Thu Aug 13 2020

.TODAY...Variable wind 10 kt. Seas 2 ft.
.TONIGHT...Variable wind 10 kt. Seas 2 ft.
.FRI...Variable wind 10 kt becoming NW 15 kt in the afternoon.
Seas 5 ft.
.FRI NIGHT...NW wind 25 kt. Seas 7 ft.
.SAT...NW wind 20 kt. Seas 7 ft.
.SUN...N wind 15 kt. Seas 3 ft.
.MON...SE wind 15 kt. Seas 3 ft.

$$

PKZ131-140100-
Barren Islands East-
353 AM AKDT Thu Aug 13 2020

.TODAY...Variable wind 10 kt. Seas 3 ft.
.TONIGHT...Variable wind 10 kt. Seas 3 ft.
.FRI...Variable wind 10 kt becoming NW 20 kt in the afternoon.
Seas 4 ft.
.FRI NIGHT...NW wind 20 kt. Seas 6 ft.
.SAT...N wind 20 kt. Seas 7 ft.
.SUN...NE wind 15 kt. Seas 6 ft.
.MON...E wind 15 kt. Seas 6 ft.

$$

PKZ132-140100-
Marmot Island to Sitkinak-
353 AM AKDT Thu Aug 13 2020

.TODAY...E wind 20 kt. Seas 5 ft.
.TONIGHT...E wind 20 kt. Seas 7 ft.
.FRI...NE wind 20 kt. Seas 7 ft. Rain.
.FRI NIGHT...NW wind 20 kt. Seas 6 ft.
.SAT...N wind 20 kt. Seas 7 ft.
.SUN...N wind 15 kt. Seas 7 ft.
.MON...E wind 15 kt. Seas 6 ft.

$$

PKZ136-140100-
Chiniak Bay-
353 AM AKDT Thu Aug 13 2020

.TODAY...Variable wind less than 10 kt. Seas 3 ft. Patchy fog.
.TONIGHT...Variable wind less than 10 kt. Seas 3 ft.
.FRI...Variable wind less than 10 kt. Seas 2 ft.
.FRI NIGHT...W wind 20 kt. Seas 2 ft.
.SAT...NW wind 15 kt. Seas 2 ft.
.SUN...Variable wind less than 10 kt. Seas 3 ft.
.MON...E wind 10 kt. Seas 3 ft.

$$

PKZ137-140100-
Marmot Bay-
353 AM AKDT Thu Aug 13 2020

.TODAY...Variable wind less than 10 kt becoming E 10 kt in the
afternoon. Seas 3 ft. Patchy fog.
.TONIGHT...E wind 10 kt in the evening becoming variable less than
10 kt. Seas 3 ft.
.FRI...Variable wind less than 10 kt becoming NW 10 kt in the
afternoon. Seas 1 ft.
.FRI NIGHT...W wind 15 kt. Seas 3 ft.
.SAT...NW wind 15 kt. Seas 3 ft.
.SUN...Variable wind less than 10 kt. Seas 3 ft.
.MON...E wind 15 kt. Seas 4 ft.

$$

PKZ138-140100-
Shelikof Strait-
353 AM AKDT Thu Aug 13 2020

.TODAY...Variable wind 10 kt becoming NE 20 kt in the afternoon.
Seas 2 ft building to 6 ft in the afternoon.
.TONIGHT...NE wind 20 kt diminishing to 10 kt. Seas 7 ft subsiding 
to 3 ft after midnight.
.FRI...Variable wind 10 kt becoming SW 15 kt in the afternoon.
Seas 3 ft.
.FRI NIGHT...W wind 15 kt. Seas 4 ft.
.SAT...NW wind 20 kt. Seas 4 ft.
.SUN...Variable wind 10 kt. Seas 3 ft.
.MON...E wind 15 kt. Seas 2 ft.

$$

PKZ139-140100-
Cook Inlet Kalgin Island to Point Bede-
353 AM AKDT Thu Aug 13 2020

.TODAY...NE wind 10 kt. Seas 2 ft.
.TONIGHT...SW wind 10 kt. Seas 3 ft.
.FRI...Variable wind less than 10 kt becoming NE 10 kt in the
afternoon. Seas 2 ft.
.FRI NIGHT...NW wind 15 kt. Seas 4 ft.
.SAT...N wind 25 kt. Seas 5 ft.
.SUN...N wind 15 kt. Seas 2 ft.
.MON...S wind 10 kt. Seas 3 ft.

$$

PKZ140-140100-
Cook Inlet North of Kalgin Island-
353 AM AKDT Thu Aug 13 2020

.TODAY...Variable wind less than 10 kt. Seas 2 ft. Patchy fog.
.TONIGHT...Variable wind less than 10 kt becoming SW 10 kt after
midnight. Seas 3 ft.
.FRI...Variable wind less than 10 kt. Seas 2 ft.
.FRI NIGHT...W wind 20 kt. Seas 6 ft.
.SAT...N wind 20 kt. Seas 6 ft.
.SUN...NW wind 15 kt. Seas 2 ft.
.MON...S wind 10 kt. Seas 3 ft.

$$

PKZ141-140100-
Kachemak Bay-
353 AM AKDT Thu Aug 13 2020

.TODAY...Variable wind less than 10 kt becoming SW 10 kt in the
afternoon. Seas 2 ft.
.TONIGHT...SW wind 10 kt in the evening becoming variable less than
10 kt. Seas 2 ft.
.FRI...Variable wind less than 10 kt becoming W 10 kt in the
afternoon. Seas 2 ft.
.FRI NIGHT...N wind 10 kt. Seas 2 ft.
.SAT...N wind 15 kt. Seas 2 ft.
.SUN...Variable wind less than 10 kt. Seas 2 ft.
.MON...Variable wind less than 10 kt. Seas 2 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
437 AM AKDT Wed Aug 12 2020

.ANALYSIS AND UPPER LEVELS...

The upper low from yesterday remains just north of the Alaska
Range early this morning, and it will continue to influence local
conditions by generating thunderstorms and showers over much of
Southcentral Alaska today and tonight. A strong shortwave extends
southward from the aforementioned upper low through Southcentral,
then runs westward through Kusko Bay then turns northward past
Yukon Delta. Increased moisture and rainfall have shifted further
east of Wrangell Mountains and further north of Alaska Range. West
of this low, an upper level high will maintain low level
clouds/stratus over much of Kusko Bay and Bristol Bay early this
morning, then gradually weakening with daytime heating. A
vertically stacked low near the Aleutian Islands is centered
northwest of Atka, and weather reports indicated an extensive area
of patchy fog and low clouds over Bering Sea and Aleutians. South
of the Aleutians, an elongated area of tropical moisture or
baroclinic zone runs through eastern Aleutians and south Alaska
Peninsula (AKPEN), and this will bring increased moisture and
clouds over western Gulf throughout today.

&&

.MODEL DISCUSSION...

Computer model resolutions are in accord for most of the large
scale features except on the motion and location of the emerging
low south of AKPEN in the coming days. Although the synoptic low
over the Aleutians will strengthen the next circulation overlaid
by the baroclinic zone, solutions begin to split starting Friday
morning as this emerging low enters western Gulf through the
weekend. Overall, solutions are doing a good job handling the
latest weather pattern.

&&

.AVIATION...

PANC...The main forecast challenge would be forecasting
thunderstorms today and tonight, especially whether thunderstorms
will occur nearby or right over Anchorage Bowl. Shower bands
continue to move from south to north, with the anticipation of
increased showers later in the day. Otherwise, light winds and
VFR conditions will prevail.

&&

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

A broad upper trough over Southcentral will continue showery
weather across the region. Cold air aloft and a strengthening
thermal trough will increase afternoon and evening thunderstorm
potential over inland areas from the Kenai Peninsula to MAT-SU
Valleys (including Anchorage Bowl) and Copper River Basin through
Thursday. Southcentral overall will experience a slow warming and
drying trend. Weak offshore flow with localized outflow winds
tonight will diminish on Thursday and give way to afternoon
seabreezes. Patchy fog will diminish in inland by the mid morning
hours.

&&

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

Expecting a pattern change to occur late on Wednesday as the upper
level low that has provided lift for afternoon and evening
showers moves off to the southeast. There is a slight chance for
an isolated thunderstorm or two over the Western Alaska Range
today due to the shortwave and some mild instability building over
the region throughout the day. Otherwise, the weather is looking
hot and increasingly dry through Fri as a ridge builds over the
central Bering Sea. This ridge location puts Southwest in the
zone of subsidence, with offshore surface flow from the interior
also helping to dry things out.

The southern AKPEN should be the only area to receive rainfall
starting early Thu morning. Models indicate a slight perturbation
in an area of baroclinicity embedded within the jet to the south
of the Aleutian Chain. This perturbation is expected to form into
a surface low that will move off of the southern AKPEN coast Thu
morning. As the system moves north, it's expected to absorb the
remnants of an upper level low over the Central Aleutian Chain.
This will bring persistent rain over the southern AKPEN through
Fri as the two systems interact.

&&

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

An occluded low over the Central Aleutians Wed is expected to
continue to weaken as it moves slowly east through Thu. The
weather impacts from this storm will continue to be rain and light
winds. To the north, surface high pressure currently centered
over St. Lawrence island is expected to expand and occupy the
northern and central Bering by Fri. This should keep the winds on
the light side and also create some fog and low stratus. The
pattern will then again to change over the Western Aleutians Thu
night as the next frontal system comes in. Models are in good
agreement in regards to small craft advisory winds and rain from
Shemya to Amchitka by Friday. Some solutions indicate Gales over
the Western Aleutians by Friday night but there is still
uncertainty in this forecast.

&&

.MARINE (Days 3 through 5: Friday through Sunday)...

Aleutians/Bering: Light winds with high pressure moves into the
Eastern Bering for Sun. A North Pacific low and its front moves
into the Western Bering through Sun. While the track and
development of the low vary through the forecast, confidence is
good for the front to spread showers and Southeasterly small craft
winds and waves with local gales developing over the Western
Aleutians Eastward for Fri afternoon. As the low tracks into the
Western Bering, winds and waves will wrap the low and spread into
the Eastern Bering by Sun. Southerly winds move with the front,
Easterly then Northerly follow behind the low.

Gulf of AK: High pressure over the Gulf dissipates for Sat. A
North Pacific low and its front moves along the Southern Gulf
through Sun. Confidence is good for showers and Easterly small
craft winds and waves across the Southern Gulf to spread Northward
mostly in the Eastern Gulf through Sun. High pressure enters the
Western Gulf Sun.

&&

.LONG TERM FORECAST (Days 4 through 7: Sat through Tue)...
Model agreement has began to improve a bit with the track a
developing North Pacific low moving into the Western Aleutians
this weekend. While there are small differences with regards to
timing, there is general consensus that this system will bring
gale force winds and rain to the Western-Central Aleutians for
Saturday. This agreement then quickly breaks down Sunday into
early next week, especially when looking at the last 2 runs from
the GFS. The GFS has begun to trend with a much deeper low
tracking into the Bering Strait, while the EC/CMC and other
ensembles continue to track this system much weaker through the
AKPen. After coordinating with WPC, the long term forecast will
treat these GFS solutions will be treated as an outlier for now,
but this will need to be continue to be monitored. If other models
begin to trend this direction, significant changes to the
forecast will be needed for the Southwest Mainland early next
week.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...CB
SOUTHCENTRAL ALASKA...BC
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...CJ
MARINE/LONG TERM...MK/DK