Small Craft Advisory 476, NWS Anchorage, AK

128 
FZAK52 PAFC 201200
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
400 AM AKDT Tue Jun 20 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.

PKZ199-210045-
400 AM AKDT Tue Jun 20 2017
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

Bogoslof Volcano 53 NM West of Dutch Harbor remains active.

A 998 mb low in the northwestern Pacific will move to 390 nm
southwest of Shemya at 999 mb tonight...then move to 270 nm
southwest of Shemya at 998 mb Wed night. The associated front 
will enter the western Aleutians Wed morning and approach the 
central Aleutians Wed night. High pressure will build over the 
eastern Bering through Wed night. 


$$

PKZ150-210045-
South of the AK Peninsula Sitkinak to Castle Cape-
400 AM AKDT Tue Jun 20 2017

...SMALL CRAFT ADVISORY TODAY...

.TODAY...NW wind 30 kt diminishing to 20 kt in the afternoon. Seas
8 ft.
.TONIGHT...W wind 20 kt. Seas 5 ft.
.WED...NW wind 15 kt. Seas 4 ft.
.WED NIGHT...Variable wind 10 kt. Seas 4 ft.
.THU...Variable wind 10 kt. Seas 3 ft.
.FRI...Variable wind 10 kt. Seas 5 ft.
.SAT...W wind 15 kt. Seas 6 ft.

$$

PKZ155-210045-
South of the AK Peninsula Castle Cape to Cape Sarichef-
400 AM AKDT Tue Jun 20 2017

.TODAY...NW wind 20 kt. Seas 7 ft.
.TONIGHT...W wind 15 kt. Seas 5 ft.
.WED...W wind 15 kt. Seas 4 ft.
.WED NIGHT...Variable wind 10 kt. Seas 4 ft.
.THU THROUGH FRI...Variable wind 10 kt. Seas 4 ft.
.SAT...SW wind 15 kt. Seas 6 ft.

$$

PKZ160-210045-
Bristol Bay-
400 AM AKDT Tue Jun 20 2017

...SMALL CRAFT ADVISORY TODAY...

.TODAY...NW wind 25 kt becoming 20 kt in the afternoon. Seas 7 ft.
.TONIGHT...W wind 20 kt. Seas 5 ft. Patchy fog.
.WED...W wind 15 kt. Seas 4 ft. Patchy fog.
.WED NIGHT...W wind 15 kt. Seas 3 ft.
.THU THROUGH FRI...W wind 10 kt. Seas 3 ft.
.SAT...W wind 15 kt. Seas 3 ft.

$$

PKZ165-210045-
Port Heiden to Cape Sarichef-
400 AM AKDT Tue Jun 20 2017

.TODAY...W wind 20 kt. Seas 6 ft. Patchy fog.
.TONIGHT...W wind 15 kt. Seas 3 ft. Patchy fog.
.WED...Variable wind 10 kt. Seas 3 ft. Patchy fog.
.WED NIGHT...Variable wind 10 kt. Seas 2 ft.
.THU THROUGH FRI...Variable wind 10 kt. Seas 3 ft.
.SAT...S wind 20 kt. Seas 3 ft.

$$

PKZ170-210045-
Cape Sarichef to Nikolski Bering Side-
400 AM AKDT Tue Jun 20 2017

.TODAY...W wind 20 kt. Seas 4 ft. Patchy fog.
.TONIGHT...W wind 15 kt. Seas 3 ft.
.WED...Variable wind 10 kt. Seas 3 ft.
.WED NIGHT...Variable wind 10 kt. Seas 2 ft.
.THU...Variable wind 10 kt. Seas 3 ft.
.FRI...S wind 20 kt. Seas 5 ft.
.SAT...S wind 25 kt. Seas 8 ft.

$$

PKZ171-210045-
Unalaska Bay-
400 AM AKDT Tue Jun 20 2017

.TODAY...W wind 15 kt. Seas 2 ft.
.TONIGHT...NW wind 15 kt becoming W after midnight. Seas 2 ft.
.WED...NW wind 10 kt in the morning becoming variable less than
10 kt. Seas 2 ft.
.WED NIGHT...Variable wind less than 10 kt. Seas 2 ft.
.THU...Variable wind less than 10 kt. Seas 2 ft.
.FRI...S wind 10 kt. Seas 1 foot.
.SAT...S wind 15 kt. Seas 2 ft.

$$

PKZ172-210045-
Cape Sarichef to Nikolski Pacific Side-
400 AM AKDT Tue Jun 20 2017

.TODAY...W wind 15 kt. Seas 5 ft.
.TONIGHT...W wind 15 kt. Seas 5 ft.
.WED...Variable wind 10 kt. Seas 4 ft.
.WED NIGHT...Variable wind 10 kt. Seas 4 ft.
.THU...Variable wind 10 kt. Seas 3 ft.
.FRI...SW wind 20 kt. Seas 7 ft.
.SAT...S wind 25 kt. Seas 13 ft.

$$

PKZ173-210045-
Nikloski to Seguam Island Bering Side-
400 AM AKDT Tue Jun 20 2017

.TODAY...Variable wind 10 kt. Seas 4 ft.
.TONIGHT...Variable wind 10 kt. Seas 3 ft.
.WED...Variable wind 10 kt. Seas 3 ft.
.WED NIGHT...Variable wind 10 kt. Seas 3 ft.
.THU...SE wind 20 kt. Seas 5 ft.
.FRI...S wind 25 kt. Seas 7 ft.
.SAT...S wind 25 kt. Seas 11 ft.

$$

PKZ174-210045-
Nikolski to Seguam Island Pacific Side-
400 AM AKDT Tue Jun 20 2017

.TODAY...SW wind 15 kt. Seas 5 ft.
.TONIGHT...Variable wind 10 kt. Seas 5 ft.
.WED...Variable wind 10 kt. Seas 5 ft.
.WED NIGHT...Variable wind 10 kt. Seas 4 ft.
.THU...S wind 20 kt. Seas 7 ft.
.FRI...S wind 25 kt. Seas 9 ft.
.SAT...S wind 30 kt. Seas 14 ft.

$$

PKZ175-210045-
Seguam Island to Adak Bering Side-
400 AM AKDT Tue Jun 20 2017

.TODAY...W wind 15 kt. Seas 3 ft.
.TONIGHT...Variable wind 10 kt. Seas 3 ft.
.WED...S wind 15 kt. Seas 3 ft.
.WED NIGHT...SE wind 20 kt. Seas 4 ft.
.THU THROUGH FRI...S wind 30 kt. Seas 8 ft.
.SAT...SE wind 25 kt. Seas 8 ft.

$$

PKZ176-210045-
Seguam Island to Adak Pacific Side-
400 AM AKDT Tue Jun 20 2017

.TODAY...W wind 15 kt. Seas 4 ft.
.TONIGHT...Variable wind 10 kt. Seas 5 ft.
.WED...S wind 15 kt. Seas 5 ft.
.WED NIGHT...SE wind 25 kt. Seas 6 ft.
.THU...SE wind 35 kt. Seas 13 ft.
.FRI THROUGH SAT...S wind 30 kt. Seas 13 ft.

$$

PKZ177-210045-
Adak to Kiska-
400 AM AKDT Tue Jun 20 2017

...SMALL CRAFT ADVISORY WEDNESDAY...

.TODAY...SW wind 15 kt. Seas 4 ft.
.TONIGHT...S wind 20 kt. Seas 4 ft.
.WED...SE wind 30 kt. Seas 7 ft.
.WED NIGHT...SE wind 35 kt. Seas 12 ft.
.THU...SE wind 35 kt. Seas 16 ft.
.FRI...S wind 25 kt. Seas 11 ft.
.SAT...E wind 25 kt. Seas 9 ft.

$$

PKZ178-210045-
Kiska to Attu-
400 AM AKDT Tue Jun 20 2017

...GALE WARNING WEDNESDAY...

.TODAY...SW wind 20 kt. Seas 6 ft.
.TONIGHT...S wind 25 kt. Seas 6 ft.
.WED...SE wind 35 kt. Seas 8 ft building to 13 ft in the
afternoon.
.WED NIGHT...SE wind 35 kt. Seas 17 ft.
.THU...SE wind 35 kt. Seas 17 ft.
.FRI...S wind 20 kt. Seas 11 ft.
.SAT...NW wind 15 kt. Seas 7 ft.

$$

PKZ179-210045-
Pribilof Islands Near Shore Waters-
400 AM AKDT Tue Jun 20 2017

.TODAY...W wind 15 kt. Seas 4 ft. Patchy fog.
.TONIGHT...Variable wind 10 kt. Seas 3 ft. Patchy fog.
.WED...Variable wind 10 kt. Seas 3 ft. Patchy fog.
.WED NIGHT...Variable wind 10 kt. Seas 3 ft.
.THU...SE wind 15 kt. Seas 3 ft.
.FRI...S wind 20 kt. Seas 6 ft.
.SAT...S wind 25 kt. Seas 11 ft.

$$

PKZ180-210045-
Kuskokwim Delta and Etolin Strait-
400 AM AKDT Tue Jun 20 2017

.TODAY...W wind 15 kt. Seas 3 ft...except 7 ft in the morning south 
of Cape Newenham. Patchy fog.
.TONIGHT...W wind 15 kt. Seas 2 ft. Patchy fog.
.WED...NW wind 10 kt increasing to 15 kt in the afternoon. Seas
3 ft. Patchy fog.
.WED NIGHT...NW wind 15 kt. Seas 3 ft.
.THU...NW wind 15 kt. Seas 3 ft.
.FRI...W wind 15 kt. Seas 3 ft.
.SAT...SW wind 15 kt. Seas 4 ft.

$$

PKZ181-210045-
North and West of Nunivak Island-
400 AM AKDT Tue Jun 20 2017

.TODAY...W wind 15 kt. Seas 3 ft. Patchy fog.
.TONIGHT...W wind 15 kt. Seas 3 ft. Patchy fog.
.WED...Variable wind 10 kt. Seas 3 ft. Patchy fog.
.WED NIGHT...SW wind 15 kt. Seas 3 ft.
.THU THROUGH FRI...S wind 15 kt. Seas 4 ft.
.SAT...S wind 20 kt. Seas 6 ft.

$$

PKZ185-210045-
Saint Matthew Island Waters-
400 AM AKDT Tue Jun 20 2017

.TODAY...W wind 20 kt. Seas 6 ft. Patchy fog.
.TONIGHT...SW wind 20 kt. Seas 6 ft. Patchy fog.
.WED...S wind 20 kt. Seas 6 ft. Patchy fog.
.WED NIGHT...S wind 20 kt. Seas 6 ft.
.THU...S wind 15 kt. Seas 6 ft.
.FRI THROUGH SAT...SE wind 20 kt. Seas 9 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
451 AM AKDT Mon Jun 19 2017

.ANALYSIS AND UPPER LEVELS...
A low south of the Gulf of Alaska is tracking north towards the
Gulf with its front already pushing through the southern Gulf. To
the north, another low sits over the northwest mainland and it is
bringing more moisture to southwest Alaska. There is also ridging
that is extending over the eastern mainland from the east.

&&

.MODEL DISCUSSION...
The models are in good synoptic agreement until Tuesday when they
struggle to handle the Gulf low as it exits to the east. This will
not only have an impact on winds over the marine zones around the
Gulf but also with shortwaves being pushed over Southcentral
Alaska. The differences the various guidances show for these waves
brings uncertainty to how much rain Southcentral Alaska will see
after the Monday night trough pushes through.

&&

.AVIATION...
PANC...VFR conditions and light winds will persist until the
evening when southerly winds will pick up. Overnight Monday, rain
will begin to accompany the strengthening southerly winds.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
Expect deteriorating conditions across Southcentral today through
tonight as a large upper level low moves into the Gulf of Alaska.
A leading upper level short-wave out ahead of this low will track
westward across Southcentral this afternoon and evening, advecting
warmer and more unstable air across inland areas. This will lead
to development of showers and thunderstorms along interior mountains
early this afternoon. A fairly stout storm motion will take
convection westward across the Copper River Basin and southwestward
across the Mat-Su down toward northern Cook Inlet. With forcing
from the upper wave expect convection to increase in areal
coverage through the afternoon and just about anywhere could see
a shower. Thunderstorms will be most likely from the Talkeetna
Mountains westward into the Susitna Valley. With warming low
level temperatures and some component of offshore flow, surface
temperatures will be notably warmer today than on Sunday.

Meanwhile, a surface front and strong upper wave will rotate
northward across the eastern Gulf today, then westward across
Southcentral tonight. Steady rain will push onshore of the
northeast Gulf coast and inland to the southeast Copper River
Basin by late this afternoon. All of this rain will spread north
and west tonight, then head back southward along the west side of
the low on Tuesday. The details of the precipitation forecast for
tonight are quite the challenge as showers out ahead of the main
trough merge with the steady rain moving in. The bottom line
though is that rain will become widespread across the region.
Tuesday will be a soaking rain from the Mat-Su southward to
Anchorage and the western Kenai. Rain will then exit to Kodiak
Island Tuesday night. Cloud cover and stable conditions will
dominate in the wake of the rain, so expect Tuesday to be a very
cool day, with temperatures maxing out in the mid to upper 50s
for most areas. By the time all is said and done expect widespread
rain totals of one third to one half inch with isolated higher
amounts of up to an inch.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2...Mon and Tue)...
Southwest AK will have to endure a few more days of showers and
thunderstorms before a drying trend ensues. For today, the area
will be pinched between a large vertically stacked low in the Gulf
of AK and a smaller, cold-core low dropping south through the
Bering Strait. So after the low stratus and patchy fog over the
Delta burns off later this morning, weak flow aloft will leave the
area vulnerable to shower development. The best chance for
thunderstorms will be along the Kuskokwim Mountains and Alaska
Range.

By late tonight into early Tue, a shortwave ridge will start to
build from the Bering. This will serve to tighten the gradient
working with the low in the Gulf. As a result, expect an increase
in north to northeast winds across interior portions of Bristol
Bay, especially over higher terrain. As the ridge pushes inland on
Tue, it will help to stabilize much of the area bringing mostly
dry conditions with continued mild temperatures. The lone
exception to this will be the very western portion of the AK Range
where some afternoon thunderstorms will still be possible. The dry
trend looks to last through at least Wed.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2...Mon and
Tue)...
There is no dominant system across the area. Many weak features
are playing a role in the forecast, but outside of light winds and
some rain, they aren't really having too much impact. High
pressure will build over the Central Bering today helping to keep
abundant marine stratus and patchy fog in the area. These
conditions will shift east with the ridge as it works towards the
west coast this week. As it approaches the Alaska Peninsula late
tonight into early Tue, north to northwest winds will make for
gusty conditions there with heavier showers on the Bering side of
the peninsula.

Meanwhile, weak systems will continue to bring light rain and
sub- small craft south to west winds to the Western Aleutians. A
stronger system will develop south of Shemya on Wed.

&&

.LONG TERM FORECAST (Days 3 through 7)...

Upper level high over the mainland will remain steadfast through
Thursday, keeping the upper level low over the gulf. This upper
high will eventually recede to the east briefly to make way for
an upper level trough to track into the southwest Mainland on
Friday. By Saturday morning, upper level ridging over the Bering
will begin to push into the southern Mainland. Further west, an
upper low over the Kamchatka Peninsula will shift eastward over
the western Aleutians by Thursday morning, then bank northward
over the far western Bering along the western periphery of the
building Bering sea ridge. What this means for the sensible
weather at the surface is the return of the thermal low forming
over the interior through much of the week, with warming
temperatures and convective afternoon/evening showers. To the
west, high pressure over the Bering may result in widespread foggy
conditions through Thursday, and rainy and windy conditions
pushing into the western Aleutians mid week with the approach of a
frontal system entering the area. The front will continue to
slowly push eastward over the central Aleutians through the
beginning of the weekend.

Models have come into better agreement overall with the synoptic
scale systems in both the upper and lower levels, especially with
regards to the timing and strength of the Bering Sea ridge.
National guidance was again heavily weighted towards the
operational EC and GFS through days 3 through 5, with a more
ensemble approach to the forecast from days 5 through 8. There
still remains some uncertainty with regards to the upper level
high over the interior and its interaction with the closed low
that is progged to be in the Gulf.

&&

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

&&

SYNOPSIS AND MODEL DISCUSSION...DK
SOUTHCENTRAL ALASKA...SEB
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MO
LONG TERM...TP