Gale Warning 387, NWS Anchorage, AK

013 
FZAK52 PAFC 212340
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
340 PM AKDT Mon Aug 21 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.

PKZ199-221300-
340 PM AKDT Mon Aug 21 2017
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 1002 mb low 420 nm southwest of Shemya will move to 110 nm 
northwest of Shemya at 990 mb Tue afternoon...then weaken to 998 
mb 150 nm northwest of Adak Wed afternoon. Another low will form
70 nm east of Saint Paul Island at 999 mb Wed afternoon.

$$

PKZ150-221300-
South of the AK Peninsula Sitkinak to Castle Cape-
340 PM AKDT Mon Aug 21 2017

...GALE WARNING TONIGHT...

.TONIGHT...NW wind 35 kt. Gusts to 45 kt in the evening out of bays
and passes. Seas 11 ft.
.TUE...NW wind 30 kt. Seas 9 ft.
.TUE NIGHT...W wind 20 kt. Seas 6 ft.
.WED...SW wind 20 kt. Seas 5 ft.
.WED NIGHT...SW wind 25 kt. Seas 9 ft.
.THU...W wind 25 kt. Seas 10 ft.
.FRI...NW wind 25 kt. Seas 9 ft.
.SAT...NW wind 20 kt. Seas 8 ft.

$$

PKZ155-221300-
South of the AK Peninsula Castle Cape to Cape Sarichef-
340 PM AKDT Mon Aug 21 2017

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...NW wind 30 kt except NW 20 kt W of the Shumagin Islands. 
Seas 7 ft.
.TUE...NW wind 20 kt. Seas 5 ft.
.TUE NIGHT...S wind 20 kt. Seas 4 ft. Rain.
.WED...SW wind 25 kt. Seas 9 ft.
.WED NIGHT...W wind 30 kt. Seas 11 ft.
.THU THROUGH FRI...NW wind 30 kt. Seas 10 ft.
.SAT...NW wind 25 kt. Seas 8 ft.

$$

PKZ160-221300-
Bristol Bay-
340 PM AKDT Mon Aug 21 2017

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...NW wind 30 kt diminishing to 20 kt after midnight. Seas 7
ft. Patchy fog.
.TUE...NW wind 20 kt. Seas 5 ft. Patchy fog.
.TUE NIGHT...W wind 20 kt. Seas 4 ft. Rain.
.WED...S wind 10 kt. Seas 2 ft.
.WED NIGHT...S wind 20 kt. Seas 4 ft.
.THU THROUGH SAT...NW wind 20 kt. Seas 7 ft.

$$

PKZ165-221300-
Port Heiden to Cape Sarichef-
340 PM AKDT Mon Aug 21 2017

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...NW wind 25 kt except NW 20 kt W of Port Moller. Seas 6 
ft.
.TUE...W wind 20 kt. Seas 5 ft.
.TUE NIGHT...S wind 20 kt except S 15 kt from Port Moller E. Seas
3 ft. Rain.
.WED...S wind 25 kt. Seas 6 ft.
.WED NIGHT...SW wind 25 kt. Seas 8 ft.
.THU THROUGH FRI...NW wind 30 kt. Seas 10 ft.
.SAT...NW wind 25 kt. Seas 7 ft.

$$

PKZ170-221300-
Cape Sarichef to Nikolski Bering Side-
340 PM AKDT Mon Aug 21 2017

...SMALL CRAFT ADVISORY TUESDAY AND TUESDAY NIGHT...

.TONIGHT...W wind 15 kt becoming variable 10 kt after midnight. Seas
3 ft.
.TUE...S wind 15 kt becoming SE 25 kt in the afternoon. Seas 4 ft.
Rain.
.TUE NIGHT...SE wind 25 kt. Seas 5 ft. Rain.
.WED AND WED NIGHT...SW wind 25 kt. Seas 9 ft.
.THU THROUGH FRI...NW wind 25 kt. Seas 10 ft.
.SAT...W wind 20 kt. Seas 7 ft.

$$

PKZ171-221300-
Unalaska Bay-
340 PM AKDT Mon Aug 21 2017

.TONIGHT...NW wind 10 kt in the evening becoming variable less
than 10 kt. Seas 3 ft.
.TUE...S wind 10 kt becoming SE 15 kt in the afternoon. Seas 2 ft. 
Rain.
.TUE NIGHT...SE wind 20 kt becoming SW 10 kt after midnight. Seas
3 ft. Rain.
.WED AND WED NIGHT...SW wind 20 kt. Seas 3 ft.
.THU THROUGH FRI...NW wind 20 kt. Seas 6 ft.
.SAT...W wind 15 kt. Seas 3 ft.

$$

PKZ172-221300-
Cape Sarichef to Nikolski Pacific Side-
340 PM AKDT Mon Aug 21 2017

...SMALL CRAFT ADVISORY TUESDAY AND TUESDAY NIGHT...

.TONIGHT...NW wind 15 kt. Seas 3 ft.
.TUE...S wind 15 kt increasing to 25 kt in the afternoon. Seas 4
ft. Rain.
.TUE NIGHT...SW wind 25 kt. Seas 7 ft.
.WED AND WED NIGHT...W wind 30 kt. Seas 11 ft.
.THU...NW wind 30 kt. Seas 12 ft.
.FRI...NW wind 30 kt. Seas 8 ft.
.SAT...W wind 20 kt. Seas 6 ft.

$$

PKZ173-221300-
Nikloski to Seguam Island Bering Side-
340 PM AKDT Mon Aug 21 2017

...SMALL CRAFT ADVISORY TUESDAY AND TUESDAY NIGHT...

.TONIGHT...SE wind increasing to 20 kt. Seas 4 ft.
.TUE...SE wind 30 kt. Seas 7 ft. Rain.
.TUE NIGHT...SW wind 25 kt. Seas 7 ft.
.WED AND WED NIGHT...W wind 25 kt. Seas 10 ft.
.THU THROUGH FRI...NW wind 20 kt. Seas 8 ft.
.SAT...SW wind 15 kt. Seas 5 ft.

$$

PKZ174-221300-
Nikolski to Seguam Island Pacific Side-
340 PM AKDT Mon Aug 21 2017

...SMALL CRAFT ADVISORY TUESDAY AND TUESDAY NIGHT...

.TONIGHT...SE wind increasing to 20 kt. Seas 4 ft.
.TUE...SE wind 25 kt. Seas 7 ft. Rain.
.TUE NIGHT...SW wind 25 kt. Seas 9 ft.
.WED...SW wind 30 kt. Seas 11 ft.
.WED NIGHT...W wind 25 kt. Seas 11 ft.
.THU...NW wind 25 kt. Seas 10 ft.
.FRI...NW wind 20 kt. Seas 7 ft.
.SAT...SW wind 15 kt. Seas 5 ft.

$$

PKZ175-221300-
Seguam Island to Adak Bering Side-
340 PM AKDT Mon Aug 21 2017

...SMALL CRAFT ADVISORY THROUGH TUESDAY NIGHT...

.TONIGHT...SE wind increasing to 30 kt. Seas 7 ft. Rain.
.TUE...SE wind 30 kt becoming S 20 kt in the afternoon. Seas 7 ft.
.TUE NIGHT...SW wind 25 kt. Seas 7 ft.
.WED...SW wind 30 kt. Seas 11 ft.
.WED NIGHT...W wind 25 kt. Seas 10 ft.
.THU...NW wind 15 kt. Seas 6 ft.
.FRI...W wind 20 kt. Seas 6 ft.
.SAT...S wind 20 kt. Seas 4 ft.

$$

PKZ176-221300-
Seguam Island to Adak Pacific Side-
340 PM AKDT Mon Aug 21 2017

...SMALL CRAFT ADVISORY THROUGH TUESDAY NIGHT...

.TONIGHT...SE wind increasing to 30 kt. Seas 7 ft. Rain.
.TUE...S wind 25 kt. Seas 8 ft.
.TUE NIGHT...SW wind 30 kt. Seas 11 ft.
.WED...SW wind 30 kt. Seas 12 ft.
.WED NIGHT...W wind 25 kt. Seas 11 ft.
.THU...NW wind 20 kt. Seas 9 ft.
.FRI...W wind 15 kt. Seas 5 ft.
.SAT...SW wind 20 kt. Seas 5 ft.

$$

PKZ177-221300-
Adak to Kiska-
340 PM AKDT Mon Aug 21 2017

...SMALL CRAFT ADVISORY THROUGH TUESDAY NIGHT...

.TONIGHT...SE wind 30 kt. Seas 8 ft. Rain.
.TUE...S wind 25 kt. Seas 9 ft.
.TUE NIGHT...SW wind 30 kt. Seas 12 ft.
.WED...SW wind 30 kt. Seas 12 ft.
.WED NIGHT...W wind 25 kt. Seas 11 ft.
.THU...W wind 15 kt. Seas 7 ft.
.FRI THROUGH SAT...S wind 25 kt. Seas 7 ft.

$$

PKZ178-221300-
Kiska to Attu-
340 PM AKDT Mon Aug 21 2017

...SMALL CRAFT ADVISORY THROUGH TUESDAY NIGHT...

.TONIGHT...E wind 30 kt. Seas 8 ft. Rain.
.TUE...S wind 25 kt. Seas 7 ft.
.TUE NIGHT...SW wind 30 kt. Seas 13 ft.
.WED...W wind 30 kt. Seas 13 ft.
.WED NIGHT...NW wind 25 kt. Seas 9 ft.
.THU...SE wind 20 kt. Seas 6 ft.
.FRI THROUGH SAT...SW wind 25 kt. Seas 7 ft.

$$

PKZ179-221300-
Pribilof Islands Near Shore Waters-
340 PM AKDT Mon Aug 21 2017

...SMALL CRAFT ADVISORY TUESDAY NIGHT...

.TONIGHT...SW wind 15 kt. Seas 4 ft. Patchy fog.
.TUE...S wind 15 kt. Seas 3 ft. Rain.
.TUE NIGHT...SE wind 25 kt. Seas 6 ft. Rain.
.WED...S wind 15 kt. Seas 5 ft.
.WED NIGHT...N wind 20 kt. Seas 7 ft.
.THU THROUGH FRI...NW wind 25 kt. Seas 8 ft.
.SAT...Variable wind 10 kt. Seas 5 ft.

$$

PKZ180-221300-
Kuskokwim Delta and Etolin Strait-
340 PM AKDT Mon Aug 21 2017

...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...W wind 25 kt except W 15 kt N of Cape Newenham. Seas 5 
ft. Areas of fog.
.TUE...W wind 15 kt. Seas 4 ft. Patchy fog.
.TUE NIGHT...W wind 15 kt becoming SW after midnight. Seas 3 ft.
.WED...SE wind 15 kt. Seas 2 ft.
.WED NIGHT...N wind 20 kt. Seas 4 ft.
.THU THROUGH FRI...NW wind 25 kt. Seas 8 ft.
.SAT...NW wind 20 kt. Seas 6 ft.

$$

PKZ181-221300-
North and West of Nunivak Island-
340 PM AKDT Mon Aug 21 2017

.TONIGHT...W wind 20 kt. Seas 5 ft. Areas of fog.
.TUE...W wind 15 kt. Seas 4 ft. Patchy fog.
.TUE NIGHT...E wind 15 kt. Seas 3 ft.
.WED...NE wind 20 kt. Seas 5 ft.
.WED NIGHT...N wind 25 kt. Seas 7 ft.
.THU...N wind 30 kt. Seas 8 ft.
.FRI...N wind 25 kt. Seas 7 ft.
.SAT...NW wind 20 kt. Seas 5 ft.

$$

PKZ185-221300-
Saint Matthew Island Waters-
340 PM AKDT Mon Aug 21 2017

.TONIGHT...W wind 15 kt. Seas 4 ft. Patchy fog.
.TUE...E of Saint Matthew Island, variable wind 10 kt. W of Saint
Matthew Island, variable wind 10 kt becoming E 15 kt in the
afternoon. Seas 3 ft.
.TUE NIGHT...E wind 15 kt. Seas 5 ft.
.WED...NE wind 20 kt. Seas 6 ft.
.WED NIGHT...N wind 25 kt. Seas 6 ft.
.THU...NW wind 25 kt. Seas 7 ft.
.FRI...NW wind 20 kt. Seas 6 ft.
.SAT...SE wind 20 kt. Seas 5 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
503 PM AKDT Sun Aug 20 2017

.ANALYSIS AND UPPER LEVELS...
Another cold upper level trough that originated over the Arctic is
currently located over the Interior and digging toward the Southwest
mainland of the state. A fairly strong ridge over the central
Bering Sea is pushing into the trough causing gusty north to
northwest winds over the eastern Bering Sea and Southwest Alaska.
The surface low is in the Gulf of Alaska and is strong enough to
bring northerly winds to much of Southcentral Alaska as well.
One interesting note with the pattern over Southcentral is that,
if it was wintertime, it is a pattern that would bring in a lot
of snow to the main population centers of Southcentral Alaska. All
the precipitation will be rain with this system, but the overall
pattern would be a snowy one if it was winter.

&&

.MODEL DISCUSSION...
Models remain in good agreement both in regards to one-another
and with run-to-run consistency. All show this latest Arctic
trough dropping out of the interior of the state, through the
Bristol Bay region overnight and into the Gulf of Alaska for
Monday and Tuesday. By Wednesday models are also all indicating
moist southwest flow returning to Southwest and Southcentral
Alaska and therefore more rain. Confidence is increasing for this
mid-week pattern to develop.

&&

.AVIATION...
PANC...Rain will persist but the low level flow is from the north
instead of the southwest with this system which is different from
most of the recent rainfalls. What is pertinent about this is
ceiling heights generally are higher with northerly flow than
southwest flow.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3/Tonight
through Wednesday)...

Widespread steady rain will persist across most of Southcentral
Alaska tonight as a surface low tracks northward across the Gulf
out ahead of a strong upper level trough/low dropping south across
Southwest Alaska and into the southwest Gulf. The upper level low
will track south of Kodiak Island late tonight then continue
east-southeast across the southern Gulf on Monday. The surface low
will be pulled southward toward the upper low leading to a
gradual tapering off of rain over Southcentral on Monday,
lingering longest along the Gulf coast. The northern half of the
Copper River Basin, from Glennallen northward, will remain on the
northern periphery of the rain shield, so expect little or no rain
from this system.

Aside from the rain, also expect robust winds with this storm
system. Expect widespread Small Craft to Gale Force winds across
the Gulf coastal waters tonight through Monday. The strongest
winds will be along the south side of the Alaska Peninsula,
including Shelikof Strait. The passage of the upper low and
accompanying jet streak will combine with tightening low level
pressure gradients to really accelerate winds through bays and
passes.

Look for a warmer, drier day across Southcentral on Tuesday as the
Gulf storm exits and weak ridging slides in from the west. Expect
increasing sunshine from the western Gulf to Cook Inlet (including
Anchorage and the Matanuska Valley) with favorable north to west
flow. It looks like clouds may hold in farther north and east on
the periphery of the exiting low and a trough crossing interior
Alaska.

There is high confidence in another widespread rain event beginning
Wednesday afternoon as a broad trough moves in from the Bering
Sea, setting up deep southwest flow. The rain will likely linger
through late in the week.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
A highly amplified pattern is on tap with an upper low over
southwest AK and the ridge axis to the west. The models continue
to drop this low south-southeastward. In the wake of the low
passage, high pressure will build in and expect a tight pressure
gradient from Bristol Bay to the AK Pen where gusty winds are
anticipated. Additionally, as the ridge moves inland expect the
skies to become partly cloudy and clear in several locations on
Monday. Tuesday will be mild and pleasant.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
High pressure will continue to build over the Bering Sea,
resulting in widespread stable conditions over much of the area.
The caveat being the eastern Bering/Aleutians and Alaska
Peninsula...where a tight pressure gradient will set up.
Anticipating gap winds south of the Alaska Peninsula to ramp up
tonight and reaching Gale force by tomorrow morning. As time
elapses a new low will approach the archipelago from the
southwest bringing rain to the western Aleutians.

&&

.LONG TERM FORECAST (Days 4 through 7)...

Beginning the extended period forecast Wednesday night, there will
be a deepening upper level trough over the state of Alaska with a
subtropical warm front at the base of this trough over the North
Pacific. Some of this moisture will be moving north toward the
Gulf, so this system will have some enhanced moisture aiding it.
Rather widespread rain in southwesterly flow aloft will be
impacting most of Southern Alaska through Thursday night. However,
by Friday, the main upper low and associated trough position will
dig into the Gulf of Alaska, so the steadiest rainfall will begin
to shift towards the coastal areas and Bristol Bay while more
showery conditions (instead of steady rain) develop over interior
locations. All the global numerical models depict a similar fate
to the upper trough as it weakens in place over the North Gulf
Coast through the weekend, likely keeping some clouds and shower
threats through the weekend.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Gales...119 120 130 131 139 150.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...EZ
SOUTHCENTRAL ALASKA...SEB
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...PS
LONG TERM...JA