Small Craft Advisory 431, NWS Anchorage, AK

039 
FZAK52 PAFC 312355
CWFALU

COASTAL WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE ALASKA
355 PM AKDT WED MAY 31 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.

PKZ199-011215-
355 PM AKDT WED MAY 31 2017
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA PENINSULA 
WATERS AND THE ALEUTIAN ISLANDS......

BOGOSLOF VOLCANO 53 NM WEST OF DUTCH HARBOR IS ACTIVE.

A 1000 MB LOW NEAR DUTCH HARBOR WILL MOVE INTO THE NORTH PACIFIC 
TONIGHT. A 995 MB LOW 280 NM WEST OF SHEMYA THU AFTERNOON WILL MOVE 
TO 120 NM WEST OF ADAK FRI AFTERNOON AT 1002 MB. 

$$

PKZ150-011215-
SOUTH OF THE AK PENINSULA SITKINAK TO CASTLE CAPE-
355 PM AKDT WED MAY 31 2017

.TONIGHT...NE WIND 20 KT. SEAS 6 FT. RAIN.
.THU...NE WIND 15 KT. SEAS 5 FT. RAIN.
.THU NIGHT...N WIND 15 KT. SEAS 5 FT.
.FRI...NW WIND 15 KT. SEAS 5 FT.
.FRI NIGHT...VARIABLE WIND 10 KT. SEAS 5 FT.
.SAT THROUGH MON...NE WIND 20 KT. SEAS 6 FT.

$$

PKZ155-011215-
SOUTH OF THE AK PENINSULA CASTLE CAPE TO CAPE SARICHEF-
355 PM AKDT WED MAY 31 2017

.TONIGHT...NE WIND 20 KT. SEAS 6 FT. RAIN.
.THU...NE WIND 15 KT. SEAS 6 FT. RAIN.
.THU NIGHT...N WIND 15 KT. SEAS 6 FT.
.FRI AND FRI NIGHT...W WIND 15 KT. SEAS 7 FT.
.SAT...SE WIND 20 KT. SEAS 7 FT.
.SUN...E WIND 25 KT. SEAS 11 FT.
.MON...NE WIND 20 KT. SEAS 11 FT.

$$

PKZ160-011215-
BRISTOL BAY-
355 PM AKDT WED MAY 31 2017

.TONIGHT...VARIABLE WIND 10 KT BECOMING NE AFTER MIDNIGHT. SEAS 2 
FT.
.THU...NE WIND 10 KT. SEAS 2 FT.
.THU NIGHT...NW WIND 15 KT. SEAS 2 FT.
.FRI...W WIND 15 KT. SEAS 2 FT.
.FRI NIGHT...SW WIND 10 KT. SEAS 3 FT.
.SAT...SE WIND 10 KT. SEAS 2 FT.
.SUN...E WIND 15 KT. SEAS 3 FT.
.MON...NE WIND 10 KT. SEAS 3 FT.

$$

PKZ165-011215-
PORT HEIDEN TO CAPE SARICHEF-
355 PM AKDT WED MAY 31 2017

.TONIGHT...NE WIND 15 KT. SEAS 3 FT.
.THU...N WIND 15 KT. SEAS 3 FT.
.THU NIGHT...W WIND 15 KT. SEAS 2 FT.
.FRI...W WIND 20 KT. SEAS 4 FT.
.FRI NIGHT...SW WIND 15 KT. SEAS 4 FT.
.SAT THROUGH SUN...NE WIND 15 KT. SEAS 3 FT.
.MON...VARIABLE WIND 10 KT. SEAS 3 FT.

$$

PKZ170-011215-
CAPE SARICHEF TO NIKOLSKI BERING SIDE-
355 PM AKDT WED MAY 31 2017

.TONIGHT...NE WIND 15 KT. SEAS 4 FT.
.THU...NW WIND 20 KT. SEAS 3 FT.
.THU NIGHT...W WIND 20 KT. SEAS 4 FT.
.FRI...W WIND 20 KT. SEAS 5 FT.
.FRI NIGHT...SW WIND 15 KT. SEAS 4 FT.
.SAT...NE WIND 15 KT. SEAS 7 FT.
.SUN...NE WIND 20 KT. SEAS 5 FT.
.MON...N WIND 15 KT. SEAS 4 FT.

$$

PKZ171-011215-
UNALASKA BAY-
355 PM AKDT WED MAY 31 2017

.TONIGHT...E WIND 20 KT BECOMING N 10 KT AFTER MIDNIGHT. SEAS 2
FT. RAIN.
.THU...NW WIND 20 KT. SEAS 3 FT.
.THU NIGHT...NW WIND 20 KT. SEAS 3 FT.
.FRI...NW WIND 20 KT. SEAS 3 FT.
.FRI NIGHT...S WIND 10 KT. SEAS 2 FT.
.SAT THROUGH SUN...NE WIND 15 KT. SEAS 3 FT.
.MON...N WIND 10 KT. SEAS 3 FT.

$$

PKZ172-011215-
CAPE SARICHEF TO NIKOLSKI PACIFIC SIDE-
355 PM AKDT WED MAY 31 2017

.TONIGHT...W WIND 20 KT EXCEPT E 20 KT FROM UNALASKA E. SEAS 7 FT. 
RAIN.
.THU...N WIND 20 KT. SEAS 7 FT.
.THU NIGHT...NW WIND 20 KT. SEAS 7 FT.
.FRI...W WIND 20 KT. SEAS 7 FT.
.FRI NIGHT...SW WIND 15 KT. SEAS 5 FT.
.SAT...E WIND 25 KT. SEAS 10 FT.
.SUN...NE WIND 25 KT. SEAS 15 FT.
.MON...N WIND 20 KT. SEAS 12 FT.

$$

PKZ173-011215-
NIKLOSKI TO SEGUAM ISLAND BERING SIDE-
355 PM AKDT WED MAY 31 2017

.TONIGHT...NW WIND 20 KT. SEAS 5 FT.
.THU...NW WIND 20 KT. SEAS 5 FT.
.THU NIGHT...W WIND 20 KT. SEAS 5 FT.
.FRI...SW WIND 20 KT. SEAS 4 FT.
.FRI NIGHT...SE WIND 15 KT. SEAS 7 FT.
.SAT...NE WIND 15 KT. SEAS 7 FT.
.SUN...N WIND 20 KT. SEAS 6 FT.
.MON...NE WIND 15 KT. SEAS 6 FT.

$$

PKZ174-011215-
NIKOLSKI TO SEGUAM ISLAND PACIFIC SIDE-
355 PM AKDT WED MAY 31 2017

...SMALL CRAFT ADVISORY THURSDAY AND THURSDAY NIGHT...

.TONIGHT...W WIND 20 KT. SEAS 7 FT.
.THU...NW WIND 25 KT. SEAS 9 FT.
.THU NIGHT...W WIND 20 KT. SEAS 8 FT.
.FRI...SW WIND 25 KT. SEAS 6 FT.
.FRI NIGHT...SE WIND 20 KT. SEAS 9 FT.
.SAT...NE WIND 20 KT. SEAS 9 FT.
.SUN...N WIND 25 KT. SEAS 13 FT.
.MON...N WIND 20 KT. SEAS 10 FT.

$$

PKZ175-011215-
SEGUAM ISLAND TO ADAK BERING SIDE-
355 PM AKDT WED MAY 31 2017

.TONIGHT...NW WIND 20 KT. SEAS 4 FT.
.THU...NW WIND 20 KT. SEAS 5 FT.
.THU NIGHT...W WIND 15 KT. SEAS 4 FT.
.FRI...S WIND 25 KT. SEAS 6 FT.
.FRI NIGHT...E WIND 15 KT. SEAS 6 FT.
.SAT THROUGH SUN...N WIND 15 KT. SEAS 6 FT.
.MON...E WIND 15 KT. SEAS 5 FT.

$$

PKZ176-011215-
SEGUAM ISLAND TO ADAK PACIFIC SIDE-
355 PM AKDT WED MAY 31 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY...

.TONIGHT...W WIND 25 KT. SEAS 8 FT.
.THU...NW WIND 20 KT. SEAS 8 FT.
.THU NIGHT...SW WIND 20 KT. SEAS 6 FT.
.FRI...S WIND 25 KT. SEAS 9 FT.
.FRI NIGHT...SE WIND 20 KT. SEAS 9 FT.
.SAT THROUGH SUN...N WIND 20 KT. SEAS 8 FT.
.MON...E WIND 15 KT. SEAS 8 FT.

$$

PKZ177-011215-
ADAK TO KISKA-
355 PM AKDT WED MAY 31 2017

...SMALL CRAFT ADVISORY TONIGHT AND THURSDAY NIGHT...

.TONIGHT...W WIND 25 KT. SEAS 9 FT.
.THU...NW WIND 20 KT BECOMING S 15 KT IN THE AFTERNOON. SEAS 6 FT.
.THU NIGHT...S WIND 25 KT. SEAS 7 FT. RAIN.
.FRI...SW WIND 25 KT. SEAS 8 FT.
.FRI NIGHT...N WIND 20 KT. SEAS 5 FT.
.SAT...N WIND 20 KT. SEAS 7 FT.
.SUN...N WIND 15 KT. SEAS 5 FT.
.MON...SE WIND 25 KT. SEAS 7 FT.

$$

PKZ178-011215-
KISKA TO ATTU-
355 PM AKDT WED MAY 31 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY...

.TONIGHT...NW WIND 25 KT BECOMING VARIABLE 15 KT AFTER MIDNIGHT. 
SEAS 8 FT.
.THU...SE WIND 25 KT. SEAS 7 FT. RAIN.
.THU NIGHT...SE WIND 20 KT BECOMING NE AFTER MIDNIGHT. SEAS 7 FT.
RAIN.
.FRI...N WIND 25 KT. SEAS 7 FT.
.FRI NIGHT...N WIND 20 KT. SEAS 7 FT.
.SAT...NW WIND 20 KT. SEAS 7 FT.
.SUN...E WIND 20 KT. SEAS 8 FT.
.MON...SE WIND 25 KT. SEAS 12 FT.

$$

PKZ179-011215-
PRIBILOF ISLANDS NEAR SHORE WATERS-
355 PM AKDT WED MAY 31 2017

.TONIGHT...NE WIND 15 KT. SEAS 4 FT. PATCHY FOG.
.THU...N WIND 15 KT. SEAS 4 FT.
.THU NIGHT...N WIND 15 KT. SEAS 4 FT.
.FRI...VARIABLE WIND 10 KT. SEAS 4 FT.
.FRI NIGHT...VARIABLE WIND 10 KT. SEAS 3 FT.
.SAT...VARIABLE WIND 10 KT. SEAS 5 FT.
.SUN...NE WIND 15 KT. SEAS 4 FT.
.MON...VARIABLE WIND 10 KT. SEAS 4 FT.

$$

PKZ180-011215-
KUSKOKWIM DELTA AND ETOLIN STRAIT-
355 PM AKDT WED MAY 31 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY NIGHT...

.TONIGHT...N WIND 15 KT INCREASING TO 25 KT AFTER MIDNIGHT N OF CAPE
NEWENHAM. SEAS 4 FT.
.THU...NE WIND 25 KT EXCEPT 10 KT FROM CAPE NEWENHAM S. SEAS 4 FT.
.THU NIGHT...NW WIND 25 KT EXCEPT 15 KT S OF CAPE NEWENHAM. SEAS 4 
FT.
.FRI...N WIND 15 KT. SEAS 4 FT.
.FRI NIGHT...W WIND 10 KT. SEAS 3 FT.
.SAT...SE WIND 10 KT. SEAS 2 FT.
.SUN THROUGH MON...N WIND 15 KT. SEAS 3 FT.

$$

PKZ181-011215-
NORTH AND WEST OF NUNIVAK ISLAND-
355 PM AKDT WED MAY 31 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY...

.TONIGHT...N WIND 25 KT. SEAS 6 FT.
.THU...N WIND 25 KT. SEAS 6 FT.
.THU NIGHT...N WIND 20 KT. SEAS 5 FT.
.FRI AND FRI NIGHT...NE WIND 15 KT. SEAS 4 FT.
.SAT THROUGH MON...N WIND 15 KT. SEAS 4 FT.

$$

PKZ185-011215-
SAINT MATTHEW ISLAND WATERS-
355 PM AKDT WED MAY 31 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY...

.TONIGHT...NE WIND 25 KT E OF SAINT MATTHEW ISLAND... NE 20 KT W
OF SAINT MATTHEW ISLAND. SEAS 5 FT. AREAS OF FOG.
.THU...NE WIND 25 KT E OF SAINT MATTHEW ISLAND... NE 15 KT W OF
SAINT MATTHEW ISLAND. SEAS 5 FT.
.THU NIGHT...NE WIND 20 KT. SEAS 4 FT.
.FRI AND FRI NIGHT...NE WIND 15 KT. SEAS 4 FT.
.SAT THROUGH MON...NE WIND 15 KT. SEAS 4 FT.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
709 PM AKDT Tue May 30 2017

.ANALYSIS AND UPPER LEVELS...
There is a trough over the Copper River basin moving slowly east,
with some showers ahead of it. High pressure is building into
southern Alaska, with the negatively tilted axis of the ridge over
southwest Alaska. Drying is occurring over most of southern Alaska
as this ridge builds in. There is a large upper low over the
Bering Sea, centered just north of the western Aleutians. A front
associated with this low stretches from the central Bering
southeast across the central and eastern Aleutians. Some moisture
ahead of this front is producing precipitation over the Alaska
peninsula.

&&

.MODEL DISCUSSION...
The numerical models are in good agreement through the short term
portion of the forecast (Thursday afternoon). Forecast confidence
is thus higher than normal.

&&

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

&&

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

Quiet weather has finally returned to Southcentral with abundant
sunshine in most areas. This pattern looks to continue through
Thursday, as warming temperatures aloft means afternoon highs
get warmer with each passing day. Weather concerns in this pattern
are few, but among them are the return of afternoon sea breezes to
most coastal locations. Some cumulus buildup has returned once
again to the Susitna Valley and Copper River Basin, but the very
marginal threat for any of those becoming thunderstorms will be
confined to the mountains of the Alaska Range.

Anchorage International Airport set a record low last night
getting down to 36 degrees. With warming temperatures aloft and
more than 18 hours of daylight, it's unlikely that it will do so
again tonight, though we may come close with low temperatures
potentially dropping under 40 degrees again. The progressively
warming air mass will result in increasing low temperatures for
the next several nights.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
The upper level ridge currently amplifying across southwest Alaska
will continue to strengthen tonight and then shift north
Wednesday to cover nearly all of mainland Alaska. The ridge will
persist in place Wednesday night and Thursday as an upper low from
the Aleutians tracks east to undercut it and become established
in the Gulf Thursday night and Friday. Offshore flow and warm dry
weather will persist through the week with temperatures increasing
into the 60s and low 70s. A thermal trough will become
established across the Kuskokwim Valley on Friday with mid level
moisture coming in from the east bringing the potential for some
isolated thunderstorms.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
The vertically stacked low in the southern Bering will track
slowly east tonight and Wednesday while the front out ahead of it
pivots across the eastern Aleutians and over the Alaska Peninsula.
The upper low will dig southeast across the central Aleutians
Wednesday night and then continue east to the southern Gulf
Thursday and Thursday night. Another low pressure system will
brush by just to the south of the western Aleutians Thursday
evening and continue slowly east through Friday.

&&

.FIRE WEATHER...
While convective indices are looking slightly less impressive and
moisture more limited for Friday, with a well defined thermal
trough stretching from interior Alaska into Southwest Alaska
providing good instability, still think isolated thunderstorms in
the Kuskokwim Valley and along the western Alaska range are a
possibility Friday. Shower and thunderstorm chances will increase
for weekend as easterly waves propagate from the Yukon Territory
across southern Alaska and could be a fire weather concern
depending on how rapidly fuels dry during the warm, dry spell this
week.

&&

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

The long range forecast Saturday through Monday brings increasing
chances for rain showers for the southern mainland and along the
gulf with a Pacific low taking a westward track across the gulf.
It is still unclear how much ridging spreads over the Bering to
the west of this system, as another dominant low over Kamchatka
tries to swing energy south and east. If the ridge centers near
the Kuskokwim Delta, very dry conditions would develop with
seasonally warm temperatures instead of the showery conditions
currently advertised. The last challenge in the forecast deals
with a fast paced low moving up from the Eastern Pacific. This
system races up toward the western Aleutians on Monday.
Conservative edits were made in the extended forecast with the
most significant changes along the gulf where models are in better
agreement with westward moving low. Only minor edits were made
across the southwest mainland and Bering as large models
discrepancies lend little need for adjustments.

&&

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

&&

SYNOPSIS AND MODEL DISCUSSION...BL
SOUTHCENTRAL ALASKA...JW
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...JR
LONG TERM...KH