Small Craft Advisory 674, NWS Anchorage, AK

190 
FZAK51 PAFC 270005
CWFAER

Coastal Waters Forecast
National Weather Service Anchorage Alaska
405 PM AKDT Thu Aug 26 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.

PKZ197-271330-
405 PM AKDT Thu Aug 26 2021
.SYNOPSIS FOR THE NORTH GULF COAST+KODIAK ISLAND WATERS+
COOK INLET...

A 1009 mb low 170 nm south of Chignik merges with a trough 225 nm
south of Homer Fri morning. Its front swings across the Gulf 
through Sat afternoon. A 1000 mb low forms 50 nm south of Seward 
Fri afternoon and moves to 80 nm south of Yakutat at 996 mb Sat 
morning.

$$

PKZ119-271330-
Cape Suckling to Cape Cleare-
405 PM AKDT Thu Aug 26 2021

...SMALL CRAFT ADVISORY FRIDAY AND FRIDAY NIGHT...

.TONIGHT...S wind 15 kt. Seas 4 ft.
.FRI...S wind 15 kt becoming SE 30 kt in the afternoon. Seas 6 ft.
Rain.
.FRI NIGHT...E wind 30 kt. Seas 12 ft. Rain.
.SAT...N wind 20 kt. Seas 7 ft.
.SAT NIGHT...Variable wind 10 kt. Seas 6 ft.
.SUN...Variable wind 10 kt. Seas 5 ft.
.MON...Variable wind 10 kt. Seas 3 ft.
.TUE...S wind 15 kt. Seas 4 ft.

$$

PKZ120-271330-
Cape Cleare to Gore Point-
405 PM AKDT Thu Aug 26 2021

...SMALL CRAFT ADVISORY FRIDAY NIGHT...

.TONIGHT...SW wind 15 kt. Seas 4 ft.
.FRI...S wind 15 kt becoming N in the afternoon. Seas 5 ft.
.FRI NIGHT...N wind 30 kt. Seas 7 ft.
.SAT...NW wind 20 kt. Seas 7 ft.
.SAT NIGHT...NW wind 15 kt. Seas 5 ft.
.SUN THROUGH MON...Variable wind 10 kt. Seas 4 ft.
.TUE...SE wind 15 kt. Seas 4 ft.

$$

PKZ121-271330-
Resurrection Bay-
405 PM AKDT Thu Aug 26 2021

...SMALL CRAFT ADVISORY FRIDAY NIGHT...

.TONIGHT...S wind 15 kt diminishing to 10 kt after midnight. Seas
3 ft. Rain.
.FRI...Variable wind less than 10 kt becoming N 15 kt in the
afternoon. Seas 3 ft. Rain.
.FRI NIGHT...N wind 25 kt. Seas 5 ft.
.SAT...N wind 25 kt. Seas 5 ft.
.SAT NIGHT...N wind 20 kt. Seas 4 ft.
.SUN...N wind 20 kt. Seas 4 ft.
.MON THROUGH TUE...N wind 10 kt. Seas 2 ft.

$$

PKZ125-271330-
Prince William Sound-
405 PM AKDT Thu Aug 26 2021

.TONIGHT...SE wind 10 kt becoming S 15 kt after midnight. 
Seas 3 ft.
.FRI...SE wind 15 kt. Seas 3 ft. Rain.
.FRI NIGHT...NE wind 20 kt. Seas 4 ft. Rain.
.SAT...NW wind 15 kt. Seas 3 ft.
.SAT NIGHT...NW wind 10 kt. Seas 2 ft.
.SUN...NW wind 10 kt. Seas 2 ft.
.MON...Variable wind less than 10 kt. Seas 2 ft.
.TUE...E wind 10 kt. Seas 2 ft.

$$

PKZ126-271330-
Port Valdez-
405 PM AKDT Thu Aug 26 2021

.TONIGHT...Variable wind less than 10 kt. Seas 2 ft. Rain.
.FRI...Variable wind less than 10 kt. Seas 2 ft. Rain.
.FRI NIGHT...NE wind 10 kt. Seas 2 ft. Rain.
.SAT AND SAT NIGHT...E wind 15 kt. Seas 3 ft.
.SUN...NE wind 10 kt. Seas 2 ft.
.MON...Variable wind 10 kt. Seas 2 ft.
.TUE...E wind 10 kt. Seas 2 ft.

$$

PKZ127-271330-
Valdez Narrows-
405 PM AKDT Thu Aug 26 2021

.TONIGHT...SW wind 15 kt. Seas 3 ft. Rain.
.FRI...SW wind 10 kt. Seas 2 ft. Rain.
.FRI NIGHT...N wind 10 kt increasing to 20 kt after midnight. Seas
3 ft. Rain.
.SAT AND SAT NIGHT...N wind 20 kt. Seas 3 ft.
.SUN...N wind 15 kt. Seas 3 ft.
.MON...N wind 10 kt. Seas 2 ft.
.TUE...Variable wind 10 kt. Seas 2 ft.

$$

PKZ128-271330-
Valdez Arm-
405 PM AKDT Thu Aug 26 2021

.TONIGHT...SW wind 15 kt. Seas 3 ft. Rain.
.FRI...Variable wind 10 kt. Seas 2 ft. Rain.
.FRI NIGHT...NE wind 10 kt increasing to 15 kt after midnight.
Seas 3 ft. Rain.
.SAT...NE wind 15 kt. Seas 3 ft.
.SAT NIGHT...N wind 10 kt. Seas 2 ft.
.SUN THROUGH TUE...NE wind 10 kt. Seas 2 ft.

$$

PKZ129-271330-
Passage Canal-
405 PM AKDT Thu Aug 26 2021

.TONIGHT...Variable wind less than 10 kt. Seas 2 ft. Rain.
.FRI...Variable wind less than 10 kt. Seas 2 ft. Rain.
.FRI NIGHT...W wind 10 kt increasing to 20 kt after midnight. 
Seas 3 ft.
.SAT AND SAT NIGHT...W wind 20 kt. Seas 3 ft.
.SUN...W wind 20 kt. Seas 3 ft.
.MON THROUGH TUE...E wind 10 kt. Seas 2 ft.

$$

PKZ130-271330-
West of Barren Islands including Kamishak Bay-
405 PM AKDT Thu Aug 26 2021

...GALE WARNING FRIDAY NIGHT...

.TONIGHT...W wind 20 kt. Seas 6 ft.
.FRI...W wind 20 kt becoming NW 30 kt in the afternoon. 
Seas 12 ft.
.FRI NIGHT...NW wind 35 kt. Seas 11 ft.
.SAT AND SAT NIGHT...W wind 30 kt. Seas 12 ft.
.SUN...W wind 25 kt. Seas 9 ft.
.MON...SW wind 15 kt. Seas 3 ft.
.TUE...E wind 15 kt. Seas 4 ft.

$$

PKZ131-271330-
Barren Islands East-
405 PM AKDT Thu Aug 26 2021

...GALE WARNING FRIDAY NIGHT...

.TONIGHT...SW wind 15 kt. Seas 4 ft.
.FRI...W wind 15 kt becoming NW 30 kt in the afternoon. Seas 4 ft
building to 9 ft in the afternoon.
.FRI NIGHT...NW wind 40 kt. Seas 10 ft.
.SAT...NW wind 35 kt. Seas 10 ft.
.SAT NIGHT...NW wind 30 kt. Seas 9 ft.
.SUN...W wind 25 kt. Seas 7 ft.
.MON...W wind 15 kt. Seas 4 ft.
.TUE...SE wind 20 kt. Seas 4 ft.

$$

PKZ132-271330-
Marmot Island to Sitkinak-
405 PM AKDT Thu Aug 26 2021

...GALE WARNING FRIDAY NIGHT...

.TONIGHT...SW wind 20 kt. Seas 4 ft.
.FRI...NW wind 20 kt increasing to 30 kt in the afternoon. 
Seas 7 ft.
.FRI NIGHT...NW wind 35 kt. Seas 10 ft.
.SAT...NW wind 30 kt. Seas 8 ft.
.SAT NIGHT...W wind 25 kt. Seas 7 ft.
.SUN...W wind 25 kt. Seas 5 ft.
.MON...SW wind 15 kt. Seas 5 ft.
.TUE...S wind 15 kt. Seas 7 ft.

$$

PKZ136-271330-
Chiniak Bay-
405 PM AKDT Thu Aug 26 2021

...SMALL CRAFT ADVISORY FRIDAY NIGHT...

.TONIGHT...Variable wind less than 10 kt. Seas 2 ft.
.FRI...NW wind 10 kt increasing to 20 kt in the afternoon. 
Seas 3 ft.
.FRI NIGHT...NW wind 25 kt. Seas 4 ft.
.SAT AND SAT NIGHT...W wind 15 kt. Seas 2 ft.
.SUN...W wind 15 kt. Seas 2 ft.
.MON...SW wind 10 kt. Seas 2 ft.
.TUE...S wind 10 kt. Seas 3 ft.

$$

PKZ137-271330-
Marmot Bay-
405 PM AKDT Thu Aug 26 2021

...SMALL CRAFT ADVISORY FRIDAY NIGHT...

.TONIGHT...Variable wind less than 10 kt becoming W 10 kt after
midnight. Seas 2 ft.
.FRI...W wind 10 kt becoming NW 20 kt in the afternoon. Seas 3 ft.
.FRI NIGHT...NW wind 25 kt. Seas 3 ft.
.SAT...NW wind 20 kt. Seas 2 ft.
.SAT NIGHT...W wind 15 kt. Seas 3 ft.
.SUN...W wind 15 kt. Seas 3 ft.
.MON...SW wind 10 kt. Seas 2 ft.
.TUE...SE wind 10 kt. Seas 3 ft.

$$

PKZ138-271330-
Shelikof Strait-
405 PM AKDT Thu Aug 26 2021

...SMALL CRAFT ADVISORY THROUGH FRIDAY NIGHT...

.TONIGHT...SW wind 25 kt. Seas 7 ft.
.FRI...W wind 15 kt becoming NW 25 kt in the afternoon. Seas 5 ft
building to 8 ft in the afternoon.
.FRI NIGHT...NW wind 25 kt. Seas 9 ft.
.SAT AND SAT NIGHT...W wind 20 kt. Seas 5 ft.
.SUN...W wind 20 kt. Seas 4 ft.
.MON...SW wind 15 kt. Seas 4 ft.
.TUE...Variable wind 10 kt. Seas 4 ft.

$$

PKZ139-271330-
Cook Inlet Kalgin Island to Point Bede-
405 PM AKDT Thu Aug 26 2021

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...SW wind 25 kt. Seas 8 ft.
.FRI...W wind 20 kt becoming N in the afternoon. Seas 7 ft.
.FRI NIGHT...N wind 20 kt. Seas 6 ft subsiding to 4 ft after
midnight.
.SAT...N wind 10 kt. Seas 3 ft.
.SAT NIGHT...W wind 10 kt. Seas 3 ft.
.SUN THROUGH MON...W wind 10 kt. Seas 2 ft.
.TUE...NE wind 10 kt. Seas 3 ft.

$$

PKZ140-271330-
Cook Inlet North of Kalgin Island-
405 PM AKDT Thu Aug 26 2021

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...S wind 25 kt. Seas 8 ft.
.FRI...SW wind 20 kt becoming NE in the afternoon. Seas 6 ft.
.FRI NIGHT...N wind 20 kt. Seas 6 ft.
.SAT...N wind 10 kt. Seas 2 ft.
.SAT NIGHT...W wind 10 kt. Seas 2 ft.
.SUN...N wind 10 kt. Seas 2 ft.
.MON...W wind 10 kt. Seas 2 ft.
.TUE...NE wind 10 kt. Seas 3 ft.

$$

PKZ141-271330-
Kachemak Bay-
405 PM AKDT Thu Aug 26 2021

.TONIGHT...SW wind 15 kt. Seas 4 ft.
.FRI...SW wind 15 kt. Seas 4 ft.
.FRI NIGHT...N wind 15 kt. Seas 2 ft.
.SAT AND SAT NIGHT...NW wind 10 kt. Seas 2 ft.
.SUN...NW wind 10 kt. Seas 2 ft.
.MON...Variable wind less than 10 kt. Seas 2 ft.
.TUE...E wind 10 kt. Seas 2 ft.

$$

765 
FZAK51 PAFC 271157
CWFAER

Coastal Waters Forecast
National Weather Service Anchorage Alaska
357 AM AKDT Fri Aug 27 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.

PKZ197-280100-
357 AM AKDT Fri Aug 27 2021
.SYNOPSIS FOR THE NORTH GULF COAST+KODIAK ISLAND WATERS+
COOK INLET...

A 1006 mb low 130 nm southeast of Kodiak City moves 90 nm southeast 
of Cordova Fri afternoon then dissipates. A 1000 mb low forms 50 nm 
south of Seward on Fri afternoon, then moves into Southeast Alaska 
at 1005 mb Sat afternoon. A 1010 mb low forms 50 nm northeast of 
Middleton Island Sat night and moves 80 nm west of Middleton Island 
at 1012 mb by Sun morning.


$$

PKZ119-280100-
Cape Suckling to Cape Cleare-
357 AM AKDT Fri Aug 27 2021

.TODAY...S wind 20 kt. Seas 5 ft. Rain.
.TONIGHT...Variable wind 15 kt becoming N 20 kt after midnight. 
Seas 6 ft.
.SAT...NW wind 20 kt. Seas 6 ft.
.SAT NIGHT...NW wind 20 kt. Seas 5 ft.
.SUN...Variable wind 10 kt. Seas 5 ft.
.MON...Variable wind 10 kt. Seas 3 ft.
.TUE...S wind 15 kt. Seas 4 ft.

$$

PKZ120-280100-
Cape Cleare to Gore Point-
357 AM AKDT Fri Aug 27 2021

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TODAY...W wind 25 kt. Seas 4 ft building to 8 ft in the afternoon.
.TONIGHT AND SAT...NW wind 30 kt. Seas 7 ft.
.SAT NIGHT...NW wind 25 kt. Seas 5 ft.
.SUN...W wind 15 kt. Seas 4 ft.
.MON...Variable wind 10 kt. Seas 3 ft.
.TUE...SE wind 20 kt. Seas 6 ft.

$$

PKZ121-280100-
Resurrection Bay-
357 AM AKDT Fri Aug 27 2021

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

.TODAY...S wind 15 kt becoming N in the afternoon. 
Seas 3 ft. Rain.
.TONIGHT...N wind increasing to 30 kt. Seas building to 6 ft.
.SAT...N wind 25 kt. Seas 5 ft.
.SAT NIGHT...N wind 20 kt. Seas 4 ft.
.SUN...N wind 15 kt. Seas 3 ft.
.MON...N wind 10 kt. Seas 2 ft.
.TUE...Variable wind 10 kt. Seas 2 ft.

$$

PKZ125-280100-
Prince William Sound-
357 AM AKDT Fri Aug 27 2021

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

.TODAY...S wind 20 kt becoming Variable 15 kt in the afternoon. 
Seas 4 ft. Rain.
.TONIGHT...NW wind increasing to 25 kt. Seas building to 5 ft. 
Rain.
.SAT...NW wind 30 kt. Seas 7 ft.
.SAT NIGHT...NW wind 25 kt. Seas 5 ft.
.SUN...NW wind 10 kt. Seas 2 ft.
.MON...Variable wind less than 10 kt. Seas 2 ft.
.TUE...E wind 10 kt. Seas 2 ft.

$$

PKZ126-280100-
Port Valdez-
357 AM AKDT Fri Aug 27 2021

.TODAY...Variable wind less than 10 kt. Seas 2 ft. Rain.
.TONIGHT...NE wind 10 kt. Seas 2 ft. Rain.
.SAT...NE wind 15 kt. Gusts to 25 kt. Seas 3 ft.
.SAT NIGHT...E wind 15 kt. Seas 3 ft.
.SUN THROUGH MON...NE wind 10 kt. Seas 2 ft.
.TUE...Variable wind less than 10 kt. Seas 2 ft.

$$

PKZ127-280100-
Valdez Narrows-
357 AM AKDT Fri Aug 27 2021

...SMALL CRAFT ADVISORY SATURDAY...

.TODAY...Variable wind 10 kt. Seas 2 ft. Rain.
.TONIGHT...N wind 10 kt increasing to 20 kt after midnight. 
Seas 3 ft. Rain.
.SAT...N wind 25 kt. Seas 3 ft.
.SAT NIGHT...N wind 20 kt. Seas 3 ft.
.SUN...N wind 15 kt. Seas 3 ft.
.MON...N wind 10 kt. Seas 2 ft.
.TUE...Variable wind 10 kt. Seas 2 ft.

$$

PKZ128-280100-
Valdez Arm-
357 AM AKDT Fri Aug 27 2021

.TODAY...SE wind 15 kt becoming NE 10 kt in the afternoon. 
Seas 3 ft. Rain.
.TONIGHT...NE wind 10 kt increasing to 15 kt after midnight. 
Seas 3 ft.
.SAT...NE wind 20 kt. Seas 4 ft.
.SAT NIGHT AND SUN...N wind 15 kt. Seas 3 ft.
.MON THROUGH TUE...NE wind 10 kt. Seas 2 ft.

$$

PKZ129-280100-
Passage Canal-
357 AM AKDT Fri Aug 27 2021

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

.TODAY...NE wind 10 kt becoming W in the afternoon. 
Seas 2 ft. Rain.
.TONIGHT...W wind 15 kt increasing to 25 kt after midnight. 
Gusts to 25 kt near Whittier increasing to 35 kt after midnight.
Seas 2 ft building to 4 ft after midnight.
.SAT...W wind 25 kt. Gusts to 35 kt near Whittier. Seas 4 ft.
.SAT NIGHT...W wind 20 kt. Seas 3 ft.
.SUN...W wind 15 kt. Seas 2 ft.
.MON THROUGH TUE...E wind 10 kt. Seas 2 ft.

$$

PKZ130-280100-
West of Barren Islands including Kamishak Bay-
357 AM AKDT Fri Aug 27 2021

...GALE WARNING THROUGH SATURDAY...

.TODAY...W wind 25 kt becoming NW 40 kt in the afternoon. 
Seas 5 ft building to 12 ft in the afternoon.
.TONIGHT...NW wind 40 kt. Seas 14 ft.
.SAT...W wind 35 kt. Seas 12 ft.
.SAT NIGHT...W wind 35 kt. Seas 11 ft.
.SUN...W wind 25 kt. Seas 7 ft.
.MON...SW wind 15 kt. Seas 3 ft.
.TUE...E wind 30 kt. Seas 8 ft.

$$

PKZ131-280100-
Barren Islands East-
357 AM AKDT Fri Aug 27 2021

...GALE WARNING THROUGH SATURDAY...

.TODAY...W wind 15 kt becoming NW 35 kt in the afternoon. 
Seas 4 ft building to 10 ft in the afternoon.
.TONIGHT AND SAT...NW wind 35 kt. Seas 12 ft.
.SAT NIGHT...NW wind 35 kt. Seas 12 ft.
.SUN...W wind 25 kt. Seas 7 ft.
.MON...Variable wind 10 kt. Seas 4 ft.
.TUE...SE wind 30 kt. Seas 8 ft.

$$

PKZ132-280100-
Marmot Island to Sitkinak-
357 AM AKDT Fri Aug 27 2021

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TODAY...W wind 20 kt becoming NW 30 kt in the afternoon. 
Seas building to 6 ft.
.TONIGHT AND SAT...NW wind 30 kt. Seas 9 ft.
.SAT NIGHT...W wind 25 kt. Seas 7 ft.
.SUN...W wind 20 kt. Seas 5 ft.
.MON...SW wind 15 kt. Seas 4 ft.
.TUE...SE wind 20 kt. Seas 7 ft.

$$

PKZ136-280100-
Chiniak Bay-
357 AM AKDT Fri Aug 27 2021

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TODAY...W wind 10 kt becoming NW 25 kt in the afternoon. 
Gusts to 35 kt in the afternoon. Seas 2 ft building to 4 ft 
in the afternoon.
.TONIGHT...NW wind 25 kt. Gusts to 35 kt. Seas 4 ft.
.SAT...NW wind 25 kt diminishing to 15 kt in the afternoon. 
Seas 4 ft subsiding to 2 ft in the afternoon.
.SAT NIGHT AND SUN...W wind 15 kt. Seas 2 ft.
.MON...SW wind 10 kt. Seas 2 ft.
.TUE...SE wind 15 kt. Seas 4 ft.

$$

PKZ137-280100-
Marmot Bay-
357 AM AKDT Fri Aug 27 2021

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TODAY...W wind 20 kt becoming NW 30 kt in the afternoon. 
Gusts to 40 kt in the afternoon. Seas 4 ft.
.TONIGHT...NW wind 30 kt. Gusts to 40 kt. Seas 5 ft.
.SAT...NW wind 30 kt diminishing to 20 kt in the afternoon. 
Seas 5 ft subsiding to 3 ft in the afternoon.
.SAT NIGHT...W wind 20 kt. Seas 3 ft.
.SUN...W wind 15 kt. Seas 3 ft.
.MON...SW wind 10 kt. Seas 3 ft.
.TUE...SE wind 20 kt. Seas 4 ft.

$$

PKZ138-280100-
Shelikof Strait-
357 AM AKDT Fri Aug 27 2021

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TODAY...W wind 20 kt becoming NW 30 kt in the afternoon. 
Gusts to 40 kt out of bays and passes in the afternoon. 
Seas building to 6 ft.
.TONIGHT...NW wind 30 kt. Gusts to 45 kt out of bays and passes. 
Seas 7 ft.
.SAT...W wind 25 kt. Seas 6 ft.
.SAT NIGHT...W wind 25 kt. Seas 5 ft.
.SUN...W wind 15 kt. Seas 3 ft.
.MON...Variable wind 10 kt. Seas 3 ft.
.TUE...E wind 20 kt. Seas 5 ft.

$$

PKZ139-280100-
Cook Inlet Kalgin Island to Point Bede-
357 AM AKDT Fri Aug 27 2021

...SMALL CRAFT ADVISORY TODAY...

.TODAY...SW wind 25 kt becoming N 15 kt in the afternoon. 
Seas 7 ft subsiding to 4 ft in the afternoon.
.TONIGHT...NW wind 20 kt. Seas 4 ft.
.SAT...Variable wind 10 kt. Seas 2 ft.
.SAT NIGHT...W wind 15 kt. Seas 2 ft.
.SUN THROUGH MON...NW wind 10 kt. Seas 2 ft.
.TUE...NE wind 15 kt. Seas 3 ft.

$$

PKZ140-280100-
Cook Inlet North of Kalgin Island-
357 AM AKDT Fri Aug 27 2021

...SMALL CRAFT ADVISORY TONIGHT...

.TODAY...SW wind 20 kt becoming N in the afternoon. 
Seas 5 ft. Rain.
.TONIGHT...NW wind 25 kt. Seas 5 ft.
.SAT...N wind 15 kt becoming SW 10 kt in the afternoon. 
Seas 3 ft.
.SAT NIGHT...W wind 15 kt. Seas 3 ft.
.SUN...Variable wind less than 10 kt. Seas 1 ft.
.MON...NW wind 10 kt. Seas 2 ft.
.TUE...NE wind 10 kt. Seas 2 ft.

$$

PKZ141-280100-
Kachemak Bay-
357 AM AKDT Fri Aug 27 2021

.TODAY...Outer Bay, SW wind 25 kt becoming NW 15 kt in the 
afternoon. Seas building to 6 ft during the morning. Inner Bay, 
SW wind 15 kt becoming NW 10 kt in the afternoon. Seas 2 ft.
.TONIGHT...N wind 15 kt. Seas 2 ft.
.SAT...NE wind 10 kt becoming W 15 kt in the afternoon. 
Seas 2 ft building to 4 ft in the afternoon.
.SAT NIGHT AND SUN...NW wind 10 kt. Seas 2 ft.
.MON...SW wind 10 kt. Seas 2 ft.
.TUE...E wind 15 kt. Seas 3 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
449 PM AKDT Wed Aug 25 2021

.ANALYSIS AND UPPER LEVELS...

A front moving across Southcentral is causing the rain around
Cook Inlet and the Susitna Valley. The front is producing
occasionally heavy rain, especially along west facing slopes of
the Chugach and Talkeetna Mountains. A few breaks in the clouds
are noted over the Copper River Basin, though the front is rapidly
approaching. Also some breaks in the stratus are evident over the
Kuskokwim Delta and to the lee of the Kuskokwim Mountains.

Elsewhere there are a few breaks in the clouds near Dutch Harbor,
south of Nunivak Island, and south of the AKPEN. Temperatures
remain near seasonal normals in the 50s to lower 60s across all of
southern Alaska.

In the upper levels, the longwave trough remains in nearly the
same place as yesterday. Two upper level lows, one headed for the
Panhandle, and the other near Adak, continue to move east around
the base of the trough. An embedded third shortwave trough is near
McGrath, helping force the rain over Southcentral in a small
southwesterly jet streak.

&&

.MODEL DISCUSSION...

The models are in decent agreement on the large scale systems
impacting Southern Alaska through Friday afternoon. There are some
discrepancies by Friday afternoon as to where the Gulf low forms
and how close to the coast a secondary low forms. This will impact
how strong the gap winds, particularly through Seward/Resurrection
Bay and Whittier/Passage Canal are by Friday. There are the
typical discrepancies in the models on how heavy the rain gets
both today and again Thursday night through Friday. However,
those differences are likely the result of differences in model
resolution (particularly how the mountains are resolved).
Otherwise, the general pattern is in very good agreement, and
forecast confidence is high. By Friday night/Saturday morning,
the speed at which the clouds clear out will make a large
difference on how cold the low temperatures get. Thus, small
differences in the models could result in large changes to the
forecast.

&&

.AVIATION...
PANC...MVFR conditions may developed as rain moves in from the
west. The rain is expected to end late tonight. VFR conditions
will return by Thursday morning, and persist through the day.
Winds out of Turnagain Arm, while not particularly strong, will
periodically impact the airport through tonight. The winds may
break for a bit Thursday morning then return Thursday afternoon.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3:
tonight through Saturday)...

A front out of the Southwest has crossed into Southcentral this
afternoon, bringing rounds of widespread rainfall to much of the
mainland. Rain has already started across Anchorage and the Mat-Su
Valleys and will spread eastwards towards the Copper Basin through
tomorrow. Rain tapers off through the day tomorrow as the trough
exits off to the east by tomorrow evening. A second trough
follows immediately behind the previous tomorrow night. Anticipate
persistent rain showers through Friday as these troughs pass
through. There will likely be a downslope component along the
eastern side of the Alaska Range with the second front, which may
aid in keeping parts of western Kenai drier than elsewhere across
Southcentral. A good amount of cold air flows in behind the second
front. 850mb temperatures are showing anywhere from -4C to -7C by
Friday night. This is a good temperature in early fall to see some
termination dust along the mountain tops. This would be the most
likely along the Talkeetna Mountains where the coldest air pocket
seems to be. Expect overnight temperatures to drop into the mid-
to-upper 30's across the Susitna Valley and Copper Basin Friday
night. Cloud cover may linger long enough across Anchorage and the
Mat-Valley to keep temperatures from dropping as far.

In addition to cold air inflow, lee side troughing and a
developing low in the Gulf creates an ideal set up for increased
gap winds through Resurrection Bay and Passage Canal.

A developing low enters the southern Gulf late Friday afternoon,
then pushes eastward towards the eastern Gulf. Colder air gets
pulled along the backside of the low, increasing winds
substantially through the Barren Islands and Shelikof Strait. This
low cycles around itself briefly in the eastern Gulf through
Saturday afternoon before pushing towards the Southeast Panhandle.
During the slight stall, periods of moderate-to-heavy rainfall
will bombard the North Gulf Coast, specifically Valdez and areas
east, Friday night. Elsewhere across Southcentral should begin
clearing up and drying out by Saturday morning

&&

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

The pattern over the next 3 days will begin unsettled and then turn
colder towards the weekend. Northwesterly winds behind today's
exiting front is bringing cooler temperatures to the region. A
second cold front will bring rain to the area on Thursday. The
higher elevations of the Kuskokwim and western Alaska Ranges
experience may experience a period of snow on the back edge of the
precipitation. Friday will be the coldest day of the period with
daytime high temperatures struggling to reach the low 50sF across
the lower Kuskokwim Valley as 850 mb temperatures are expected to
range between -5C and -8C. Friday night is likely to be the first
freeze of the season with overnight lows expected to fall slightly
below the freezing mark. Saturday will see temperatures rebound
slightly as winds gradually shift to southwesterly.

&&

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

An unsettled but benign weather pattern will continue across the
Bering/Aleutians over the next 3 days. A cold front will move across
the central and eastern Bering/Aleutians on Thursday, bringing
showers across the area. High pressure will then build in from the
west behind the front. Winds will remain below gale force and no
high seas expected.

&&

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

Expect winds less than 35 kts and seas less than 20 ft for the
Day 3 through 5 period. The one exception will be Gale force gap
winds are expected to develop over the Barren Islands and
Sitkinak gaps by late Saturday, diminishing to less than gale
force winds by Monday.

&&

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

A weak shortwave trough moving across interior Alaska may bring
some cloud cover to portions of the area for the day on Sunday.
Otherwise a longwave ridge is expected to continue building into
southern Mainland Alaska, setting up a period of dry weather for
much of southern Alaska. Any cold air from Saturday will be long
gone by Sunday, so depending on the amount of sunshine,
temperatures will be at or above seasonal normals.

The upper level ridge will shift east over Southcentral on Monday,
as the next low and associated fronts and precipitation move into
Southwest Alaska. Thus, the drier weather will end late in the day
Monday for areas of Southwest Alaska near the coast...and high
level cloud cover should advect over Southcentral, resulting in at
least some filtered sunshine.

By Tuesday there are some differences in timing as to how quickly
the precipitation with the aforementioned front moves into
Southcentral. Since usually the models are too quick to move
ridges away, a slower solution proposed by the Canadian looks most
reasonable, bringing rain across Southcentral late Wednesday
afternoon through the evening.

By Wednesday the differences in the models as to how fast the
precipitation moves across Southcentral into the Copper Basin and
the Gulf increase further. There is very low forecast confidence
by Wednesday.

It should be noted that the GFS strays significantly from the EC
and the Canadian as early as Sunday. Thus, the above discussion is
based on an EC/Canadian blend. However, despite the GFS being the
outlier, it's very stubborn persistence of the longwave ridge
persisting at least through Wednesday (and likely longer) should
not be ignored entirely due again to the tendency of the models to
break down longwave ridges too quickly. A perfect prog with the
GFS would mean most of Southcentral doesn't see a drop of rain for
much of next week, and that trend is only briefly interrupted by a
dissipating front moving over Southwest Alaska on Wednesday.

&&

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

&&

SYNOPSIS AND MODEL DISCUSSION...JPW
SOUTHCENTRAL ALASKA...KM
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...ED
MARINE/LONG TERM...MK/JPW