Small Craft Advisory 672, NWS Anchorage, AK

929 
FZAK52 PAFC 112340
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
340 PM AKDT Mon Sep 11 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.

PKZ199-121230-
340 PM AKDT Mon Sep 11 2017
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...
A 989 mb low 200 nm north of Attu will move to 125 nm west of St
Paul at 989 mb Tue afternoon and then move to 175 nm southwest of
Nome at 996 mb Wed afternoon. A weather front in the eastern 
Bering Sea will move into the western Gulf of Alaska Tue night.

$$

PKZ150-121230-
South of the AK Peninsula Sitkinak to Castle Cape-
340 PM AKDT Mon Sep 11 2017

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

.TONIGHT...SW wind 15 kt becoming S 25 kt after midnight. Seas 5 ft.
.TUE...S wind 30 kt. Seas 8 ft.
.TUE NIGHT...S wind 30 kt. Seas 12 ft. Rain.
.WED AND WED NIGHT...S wind 30 kt. Seas 13 ft.
.THU...W wind 15 kt. Seas 8 ft.
.FRI...S wind 25 kt. Seas 12 ft.
.SAT...NW wind 25 kt. Seas 14 ft.

$$

PKZ155-121230-
South of the AK Peninsula Castle Cape to Cape Sarichef-
340 PM AKDT Mon Sep 11 2017

...GALE WARNING TUESDAY AND TUESDAY NIGHT...

.TONIGHT...S wind 30 kt except S 25 kt from the Shumagin Islands E. 
Seas 9 ft. Rain.
.TUE...S wind 35 kt. Seas 13 ft. Rain.
.TUE NIGHT...S wind 35 kt. Seas 14 ft. Rain.
.WED...SW wind 30 kt. Seas 12 ft.
.WED NIGHT...W wind 20 kt. Seas 9 ft.
.THU...SW wind 30 kt. Seas 8 ft.
.FRI...SW wind 40 kt. Seas 18 ft.
.SAT...W wind 40 kt. Seas 18 ft.

$$

PKZ160-121230-
Bristol Bay-
340 PM AKDT Mon Sep 11 2017

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

.TONIGHT...S wind 20 kt increasing to 30 kt after midnight. Seas
5 ft.
.TUE...S wind 30 kt. Seas 7 ft. Rain.
.TUE NIGHT...S wind 30 kt. Seas 8 ft. Rain.
.WED...S wind 25 kt. Seas 6 ft.
.WED NIGHT...S wind 15 kt. Seas 5 ft.
.THU...SW wind 20 kt. Seas 5 ft.
.FRI...SE wind 30 kt. Seas 6 ft.
.SAT...NE wind 15 kt. Seas 6 ft.

$$

PKZ165-121230-
Port Heiden to Cape Sarichef-
340 PM AKDT Mon Sep 11 2017

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

.TONIGHT...S wind 30 kt. Seas 7 ft.
.TUE...S wind 30 kt. Seas 8 ft. Rain.
.TUE NIGHT...S wind 30 kt. Seas 8 ft. Rain.
.WED...S wind 25 kt. Seas 8 ft.
.WED NIGHT...W wind 15 kt. Seas 7 ft.
.THU...S wind 30 kt. Seas 7 ft.
.FRI...S wind 30 kt. Seas 14 ft.
.SAT...NW wind 30 kt. Seas 16 ft.

$$

PKZ170-121230-
Cape Sarichef to Nikolski Bering Side-
340 PM AKDT Mon Sep 11 2017

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

.TONIGHT...SW wind 30 kt. Seas 7 ft.
.TUE...SW wind 30 kt. Seas 8 ft.
.TUE NIGHT...SW wind 30 kt. Seas 10 ft.
.WED...W wind 20 kt. Seas 9 ft.
.WED NIGHT...W wind 15 kt. Seas 7 ft.
.THU...S wind 35 kt. Seas 9 ft.
.FRI...W wind 45 kt. Seas 17 ft.
.SAT...NW wind 45 kt. Seas 14 ft.

$$

PKZ171-121230-
Unalaska Bay-
340 PM AKDT Mon Sep 11 2017

.TONIGHT...SW wind 20 kt. Seas 3 ft.
.TUE...S wind 15 kt. Seas 2 ft.
.TUE NIGHT...SW wind 20 kt. Seas 3 ft. Rain showers.
.WED AND WED NIGHT...W wind 15 kt. Seas 2 ft.
.THU...S wind 25 kt. Seas 4 ft.
.FRI...SW wind 35 kt. Seas 5 ft.
.SAT...NW wind 35 kt. Seas 12 ft.

$$

PKZ172-121230-
Cape Sarichef to Nikolski Pacific Side-
340 PM AKDT Mon Sep 11 2017

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

.TONIGHT...S wind 30 kt. Seas 10 ft. Rain.
.TUE...S wind 30 kt. Seas 11 ft. Rain.
.TUE NIGHT...SW wind 25 kt. Seas 10 ft.
.WED...W wind 25 kt. Seas 9 ft.
.WED NIGHT...W wind 15 kt. Seas 8 ft.
.THU...S wind 30 kt. Seas 11 ft.
.FRI THROUGH SAT...W wind 45 kt. Seas 15 ft.

$$

PKZ173-121230-
Nikloski to Seguam Island Bering Side-
340 PM AKDT Mon Sep 11 2017

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

.TONIGHT...SW wind 25 kt. Seas 7 ft.
.TUE...SW wind 30 kt. Seas 11 ft.
.TUE NIGHT...SW wind 30 kt. Seas 12 ft.
.WED...W wind 25 kt. Seas 9 ft.
.WED NIGHT...SW wind 20 kt. Seas 8 ft.
.THU...S wind 30 kt. Seas 9 ft.
.FRI THROUGH SAT...W wind 45 kt. Seas 13 ft.

$$

PKZ174-121230-
Nikolski to Seguam Island Pacific Side-
340 PM AKDT Mon Sep 11 2017

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

.TONIGHT...SW wind 25 kt. Seas 9 ft.
.TUE...SW wind 30 kt. Seas 10 ft.
.TUE NIGHT...SW wind 30 kt. Seas 11 ft.
.WED...W wind 20 kt. Seas 10 ft.
.WED NIGHT...SW wind 15 kt. Seas 8 ft.
.THU...S wind 35 kt. Seas 10 ft.
.FRI THROUGH SAT...W wind 45 kt. Seas 13 ft.

$$

PKZ175-121230-
Seguam Island to Adak Bering Side-
340 PM AKDT Mon Sep 11 2017

...GALE WARNING TUESDAY...

.TONIGHT...SW wind 30 kt. Seas 9 ft. Rain.
.TUE...SW wind 35 kt. Seas 14 ft.
.TUE NIGHT...W wind 25 kt. Seas 12 ft.
.WED...W wind 20 kt. Seas 10 ft.
.WED NIGHT...S wind 20 kt. Seas 7 ft.
.THU...S wind 35 kt. Seas 8 ft.
.FRI THROUGH SAT...W wind 40 kt. Seas 11 ft.

$$

PKZ176-121230-
Seguam Island to Adak Pacific Side-
340 PM AKDT Mon Sep 11 2017

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

.TONIGHT...SW wind 25 kt. Seas 10 ft.
.TUE...SW wind 30 kt. Seas 13 ft.
.TUE NIGHT...W wind 30 kt diminishing to 20 kt after midnight.
Seas 12 ft.
.WED...W wind 15 kt. Seas 9 ft.
.WED NIGHT...SW wind 20 kt. Seas 6 ft.
.THU...S wind 35 kt. Seas 12 ft.
.FRI THROUGH SAT...W wind 40 kt. Seas 12 ft.

$$

PKZ177-121230-
Adak to Kiska-
340 PM AKDT Mon Sep 11 2017

...GALE WARNING THROUGH TUESDAY...

.TONIGHT...SW wind 35 kt. Seas 13 ft.
.TUE...W wind 35 kt. Seas 14 ft.
.TUE NIGHT...NW wind 25 kt becoming W 15 kt after midnight. Seas
12 ft.
.WED AND WED NIGHT...SW wind 15 kt. Seas 7 ft.
.THU THROUGH FRI...NW wind 35 kt. Seas 10 ft.
.SAT...W wind 30 kt. Seas 10 ft.

$$

PKZ178-121230-
Kiska to Attu-
340 PM AKDT Mon Sep 11 2017

...GALE WARNING TONIGHT...

.TONIGHT...W wind 35 kt. Seas 13 ft.
.TUE...NW wind 30 kt diminishing to 20 kt in the afternoon. Seas
12 ft.
.TUE NIGHT...NW wind 15 kt. Seas 11 ft.
.WED AND WED NIGHT...NW wind 15 kt. Seas 7 ft.
.THU THROUGH FRI...W wind 30 kt. Seas 10 ft.
.SAT...SW wind 25 kt. Seas 7 ft.

$$

PKZ179-121230-
Pribilof Islands Near Shore Waters-
340 PM AKDT Mon Sep 11 2017

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

.TONIGHT...SW wind 25 kt. Seas 9 ft. Rain.
.TUE...S wind 25 kt. Seas 9 ft. Rain.
.TUE NIGHT...S wind 25 kt. Seas 10 ft.
.WED...W wind 20 kt. Seas 9 ft.
.WED NIGHT...W wind 15 kt. Seas 7 ft.
.THU...S wind 30 kt. Seas 9 ft.
.FRI THROUGH SAT...NW wind 30 kt. Seas 9 ft.

$$

PKZ180-121230-
Kuskokwim Delta and Etolin Strait-
340 PM AKDT Mon Sep 11 2017

...GALE WARNING TONIGHT...

.TONIGHT...S wind 35 kt. Seas 8 ft. Periods of rain.
.TUE...S wind 30 kt. Seas 9 ft. Rain.
.TUE NIGHT...S wind 30 kt. Seas 9 ft. Rain.
.WED...S wind 25 kt. Seas 8 ft.
.WED NIGHT...SW wind 20 kt. Seas 7 ft.
.THU...SW wind 30 kt. Seas 8 ft.
.FRI...SE wind 35 kt. Seas 9 ft.
.SAT...N wind 20 kt. Seas 8 ft.

$$

PKZ181-121230-
North and West of Nunivak Island-
340 PM AKDT Mon Sep 11 2017

...SMALL CRAFT ADVISORY THROUGH TUESDAY...

.TONIGHT...S wind 30 kt. Seas 9 ft. Periods of rain.
.TUE...S wind 30 kt diminishing to 20 kt in the afternoon. Seas
8 ft. Rain.
.TUE NIGHT...S wind 20 kt. Seas 7 ft. Rain.
.WED...SW wind 20 kt. Seas 6 ft.
.WED NIGHT...W wind 20 kt. Seas 7 ft.
.THU...SW wind 30 kt. Seas 8 ft.
.FRI...E wind 30 kt. Seas 8 ft.
.SAT...N wind 25 kt. Seas 7 ft.

$$

PKZ185-121230-
Saint Matthew Island Waters-
340 PM AKDT Mon Sep 11 2017

...GALE WARNING TONIGHT...

.TONIGHT...SE wind 30 kt E of Saint Matthew Island... NE 35 kt W
of Saint Matthew Island. Seas 10 ft. Rain.
.TUE...E of Saint Matthew Island, S wind 30 kt diminishing to 20
kt in the afternoon. W of Saint Matthew Island, NE wind 30 kt. Seas 
11 ft. Rain.
.TUE NIGHT...E of Saint Matthew Island, S wind 15 kt becoming W
25 kt after midnight. W of Saint Matthew Island, N wind 25 kt.
Seas 10 ft. Rain.
.WED...NW wind 25 kt. Seas 9 ft.
.WED NIGHT...NW wind 15 kt. Seas 6 ft.
.THU...SE wind 25 kt. Seas 9 ft.
.FRI...NE wind 30 kt. Seas 10 ft.
.SAT...N wind 25 kt. Seas 10 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
509 PM AKDT Sun Sep 10 2017

.ANALYSIS AND UPPER LEVELS...

An upper level trough still covers much of the Alaska mainland,
with an associated upper level low slowly weakening and drifting
eastward in the Gulf of Alaska. While forcing with this system
remains weak, the sounding this morning shows that lapse rates
are steep enough and moisture is sufficient for widespread
showers. However, the sounding this morning also indicates
downslope cross barrier flow, along with drying below the
mountains and dry adiabatic lapse rates, which indicates
downsloping is certainly limiting precipitation amounts.
Meanwhile, a weak upper level wave moving across the southwest
mainland is producing showers that are even more sparse across the
Kuskokwim Delta and Bristol Bay areas. An impressive upper level
ridge still maintains hold across much of the Bering supporting a
wide swath of stratus, but a low is beginning to nudge in from the
west near Kamchatka.

&&

.MODEL DISCUSSION...

Models remain in great agreement and continue to have above
average run to run consistency, resulting in greater confidence
than average. Generally the higher resolution NAM-nest was
favored. There is still some uncertainty in the location and
intensity of showers over the next several days across
Southcentral, but generally areas of steeper terrain are favored.

&&

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

&&

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

Two weak upper lows over Southern Alaska and the Gulf of Alaska
this afternoon will merge then move eastward Monday afternoon.
Afternoon showers are prevalent, but given the weak upper level
steering flow, they are mainly impacting the mountains with the
exception of the Susitna Valley where weak southerly flow is
locally enhancing showers. The shortwave trough over the Lower
Kuskokwim Valley will move east early Monday morning with a threat
for isolated showers/drizzle along and near the Chugach and
Talkeetna Mountains, otherwise, Monday will be rather dry over
most of the region as ridging builds in behind the trough.

On Tuesday, clouds will move back into Southcentral ahead of a
Bering trough. The pressure gradient will also increase across the
Chugach Mountains, bringing in gusty afternoon southeast winds to
favored locations like Turnagain Arm (including parts of
Anchorage) and the Copper Basin. Rain will favor the Susitna
Valley and Alaska Range, and the Kenai coastline. However, rain
will not be heavy through Tuesday as the main upper level forcing
will remain well west of Southcentral. Expect strong downslope
drying for interior locations through Tuesday afternoon.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 3)...
High pressure will bring a brief round of benign weather to the
region before conditions begin to deteriorate late Monday. In the
early term the main forecast concern will be for the development
of fog/stratus around the Kuskokwim Delta and lower elevations of
Bristol Bay tonight with onshore flow and clearing skies. This is
most likely to occur in the King Salmon area which has been
consistently receiving fog over the past 2 nights, and is
expected to develop again tonight with stronger stability and
clearing skies. Onshore flow will continue throughout the coast
for most of the day tomorrow as well, so anything that does
develop will likely linger longer into the day. By Monday evening
the focus will quickly shift to the incoming frontal system over
the Bering. There remains good confidence that this system will
bring widespread rains to the area by Tuesday morning that will
persist through mid-week. The heaviest of this rain will generally
hold off until deep southerly flow develops late Tuesday-
Wednesday when many areas of Bristol Bay are expected to receive
an inch or more of rain in addition to Tuesday's rain.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 through 3)...
The forecast focus has clearly shifted to the approaching gale
force low over the Bering that will bring rain and gusty winds
throughout the region into mid-week. Overall there has been little
change in the forecast with this system with continued good
agreement and high confidence. The biggest change was to bring
increased winds into the Western-Central Bering as cold air
advection develops behind the low, which is now expected to bring
another round of gales to the area on Tuesday.

&&

.LONG TERM FORECAST (Days 3 through 7)...
The upper level pattern during the mid to late week will be
dominated by a longwave trough digging across the Bering and a
high amplitude ridge centered over the ALCAN border moving off to
the east. Southwest flow out ahead of an associated surface low
will spread precipitation across much of the region on Wednesday
and Thursday. The active pattern continues as a low pressure
system coming off of the northern tip of Japan will transit NE
towards the Western Aleutians and rapidly strengthen as it reaches
the Bering Sea. There is a fair amount of model spread this far
out with disagreements on the low track, though there seems to be
some consensus with the most recent Euro/Canadian runs showing the
low center moving into the southern Bering then SE across the
AKPEN into the southern Gulf of Alaska by the weekend.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Gale 177 178 185.

&&

SYNOPSIS AND MODEL DISCUSSION...EN
SOUTHCENTRAL ALASKA...JA
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...DEK
LONG TERM...KV