Small Craft Advisory 237, NWS Anchorage, AK

012 
FZAK51 PAFC 201140
CWFAER

COASTAL WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE ALASKA
340 AM AKDT MON MAR 20 2017

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.

PKZ197-210045-
340 AM AKDT MON MAR 20 2017
.SYNOPSIS FOR THE NORTH GULF COAST+KODIAK ISLAND WATERS+
COOK INLET...
A 1010 MB LOW 40 NM SOUTH OF SEWARD WILL DISSIPATES MON NIGHT. A 
1006 MB LOW FORMS 225 NM SOUTH OF MIDDLETON ISLAND MON NIGHT AND 
MOVES TO 135 NM SOUTHEAST OF MIDDLETON ISLAND AT 1000 MB WED 
MORNING.

$$

PKZ119-210045-
CAPE SUCKLING TO CAPE CLEARE-
340 AM AKDT MON MAR 20 2017

.TODAY...S WIND 20 KT. SEAS 5 FT. SNOW SHOWERS.
.TONIGHT...VARIABLE WIND 10 KT BECOMING N 20 KT AFTER MIDNIGHT.
SEAS 5 FT.
.TUE THROUGH WED...N WIND 20 KT. SEAS 6 FT.
.THU THROUGH FRI...NE WIND 15 KT. SEAS 4 FT.

$$

PKZ120-210045-
CAPE CLEARE TO GORE POINT-
340 AM AKDT MON MAR 20 2017

.TODAY...N WIND 20 KT. SEAS 5 FT.
.TONIGHT...N WIND 15 KT. SEAS 4 FT.
.TUE...N WIND 15 KT. SEAS 4 FT.
.TUE NIGHT...N WIND 20 KT. SEAS 6 FT.
.WED...N WIND 15 KT. SEAS 5 FT.
.THU THROUGH FRI...N WIND 20 KT. SEAS 5 FT.

$$

PKZ121-210045-
RESURRECTION BAY-
340 AM AKDT MON MAR 20 2017

...HEAVY FREEZING SPRAY WARNING TONIGHT AND TUESDAY...
...SMALL CRAFT ADVISORY TUESDAY...

.TODAY...N WIND 15 KT DIMINISHING TO 10 KT IN THE AFTERNOON. SEAS
3 FT. FREEZING SPRAY.
.TONIGHT...N WIND 10 KT INCREASING TO 15 KT AFTER MIDNIGHT. SEAS
3 FT. HEAVY FREEZING SPRAY AFTER MIDNIGHT.
.TUE...N WIND 25 KT. SEAS 5 FT. HEAVY FREEZING SPRAY DURING THE
MORNING.
.TUE NIGHT...N WIND 25 KT. SEAS 5 FT.
.WED...N WIND 30 KT. SEAS 6 FT.
.THU THROUGH FRI...N WIND 25 KT. SEAS 5 FT.

$$

PKZ125-210045-
PRINCE WILLIAM SOUND-
340 AM AKDT MON MAR 20 2017

.TODAY...E WIND 15 KT. SEAS 3 FT.
.TONIGHT...N WIND 10 KT INCREASING TO 15 KT AFTER MIDNIGHT. SEAS
3 FT.
.TUE...N WIND 20 KT. SEAS 4 FT. FREEZING SPRAY.
.TUE NIGHT...N WIND 20 KT. SEAS 4 FT.
.WED...N WIND 15 KT. SEAS 3 FT.
.THU THROUGH FRI...NE WIND 20 KT. SEAS 4 FT.

$$

PKZ126-210045-
PORT VALDEZ-
340 AM AKDT MON MAR 20 2017

...SMALL CRAFT ADVISORY TUESDAY...

.TODAY...NE WIND 10 KT INCREASING TO 15 KT IN THE AFTERNOON. SEAS
3 FT.
.TONIGHT...NE WIND 15 KT. SEAS 3 FT. FREEZING SPRAY.
.TUE...NE WIND 25 KT. SEAS 5 FT. FREEZING SPRAY.
.TUE NIGHT...NE WIND 25 KT. SEAS 5 FT.
.WED...NE WIND 25 KT. SEAS 5 FT.
.THU THROUGH FRI...NE WIND 20 KT. SEAS 4 FT.

$$

PKZ127-210045-
VALDEZ NARROWS-
340 AM AKDT MON MAR 20 2017

...HEAVY FREEZING SPRAY WARNING TONIGHT AND TUESDAY...
...SMALL CRAFT ADVISORY TONIGHT AND TUESDAY...

.TODAY...NE WIND 20 KT. SEAS 3 FT.
.TONIGHT...NE WIND 30 KT. SEAS 3 FT. HEAVY FREEZING SPRAY.
.TUE...NE WIND 30 KT. SEAS 3 FT. HEAVY FREEZING SPRAY.
.TUE NIGHT...NE WIND 30 KT. SEAS 3 FT.
.WED THROUGH FRI...NE WIND 30 KT. SEAS 3 FT.

$$

PKZ128-210045-
VALDEZ ARM-
340 AM AKDT MON MAR 20 2017

...SMALL CRAFT ADVISORY TUESDAY...

.TODAY...NE WIND 10 KT. SEAS 2 FT.
.TONIGHT...NE WIND 20 KT. SEAS 4 FT.
.TUE...NE WIND 25 KT. SEAS 5 FT. FREEZING SPRAY.
.TUE NIGHT...NE WIND 25 KT. SEAS 5 FT.
.WED THROUGH FRI...NE WIND 25 KT. SEAS 5 FT.

$$

PKZ129-210045-
PASSAGE CANAL-
340 AM AKDT MON MAR 20 2017

.TODAY...VARIABLE WIND LESS THAN 10 KT. SEAS 2 FT. SNOW SHOWERS.
.TONIGHT...E WIND 10 KT BECOMING W 15 KT AFTER MIDNIGHT. SEAS 2
FT.
.TUE...W WIND 20 KT. SEAS 3 FT. FREEZING SPRAY.
.TUE NIGHT...W WIND 20 KT. SEAS 3 FT.
.WED...W WIND 25 KT. SEAS 4 FT.
.THU THROUGH FRI...W WIND 15 KT. SEAS 2 FT.

$$

PKZ130-210045-
WEST OF BARREN ISLANDS INCLUDING KAMISHAK BAY-
340 AM AKDT MON MAR 20 2017

...SMALL CRAFT ADVISORY THROUGH TUESDAY...

.TODAY...NW WIND 25 KT DIMINISHING TO 15 KT IN THE AFTERNOON. SEAS
7 FT. FREEZING SPRAY.
.TONIGHT...NW WIND 25 KT. SEAS 8 FT. FREEZING SPRAY.
.TUE...NW WIND 30 KT. SEAS 9 FT. FREEZING SPRAY.
.TUE NIGHT...NW WIND 30 KT. SEAS 7 FT.
.WED THROUGH THU...NW WIND 30 KT. SEAS 9 FT.
.FRI...NW WIND 25 KT. SEAS 5 FT.

$$

PKZ131-210045-
BARREN ISLANDS EAST-
340 AM AKDT MON MAR 20 2017

...SMALL CRAFT ADVISORY THROUGH TUESDAY...

.TODAY...NW WIND 25 KT BECOMING N 15 KT IN THE AFTERNOON. SEAS 6
FT. FREEZING SPRAY.
.TONIGHT...NW WIND 25 KT. SEAS 6 FT. FREEZING SPRAY.
.TUE...N WIND 30 KT. SEAS 8 FT.
.TUE NIGHT...N WIND 35 KT. SEAS 8 FT.
.WED...NW WIND 35 KT. SEAS 8 FT.
.THU...NW WIND 30 KT. SEAS 6 FT.
.FRI...N WIND 20 KT. SEAS 5 FT.

$$

PKZ132-210045-
MARMOT ISLAND TO SITKINAK-
340 AM AKDT MON MAR 20 2017

...SMALL CRAFT ADVISORY TUESDAY...

.TODAY...N WIND 20 KT. SEAS 5 FT.
.TONIGHT...N WIND 20 KT. SEAS 6 FT.
.TUE...N WIND 20 KT EXCEPT NW 30 KT N OF DANGEROUS CAPE. SEAS 9
FT.
.TUE NIGHT...N WIND 30 KT. SEAS 9 FT.
.WED THROUGH THU...NW WIND 30 KT. SEAS 7 FT.
.FRI...N WIND 20 KT. SEAS 5 FT.

$$

PKZ136-210045-
CHINIAK BAY-
340 AM AKDT MON MAR 20 2017

...SMALL CRAFT ADVISORY TUESDAY...

.TODAY...W WIND 10 KT IN THE MORNING BECOMING VARIABLE LESS THAN
10 KT. SEAS 2 FT.
.TONIGHT...N WIND 10 KT BECOMING NW 15 KT AFTER MIDNIGHT. SEAS 2
FT. FREEZING SPRAY AFTER MIDNIGHT.
.TUE...NW WIND 25 KT. SEAS 4 FT. FREEZING SPRAY DURING THE MORNING.
.TUE NIGHT...NW WIND 20 KT. SEAS 4 FT.
.WED...NW WIND 25 KT. SEAS 3 FT.
.THU THROUGH FRI...NW WIND 15 KT. SEAS 2 FT.

$$

PKZ137-210045-
MARMOT BAY-
340 AM AKDT MON MAR 20 2017

...SMALL CRAFT ADVISORY TUESDAY...

.TODAY...W WIND 10 KT. SEAS 2 FT.
.TONIGHT...N WIND 15 KT. SEAS 2 FT. FREEZING SPRAY.
.TUE...NW WIND 25 KT. SEAS 4 FT. FREEZING SPRAY DURING THE MORNING.
.TUE NIGHT...NW WIND 25 KT. SEAS 3 FT.
.WED...NW WIND 25 KT. SEAS 3 FT.
.THU THROUGH FRI...NW WIND 15 KT. SEAS 2 FT.

$$

PKZ138-210045-
SHELIKOF STRAIT-
340 AM AKDT MON MAR 20 2017

.TODAY...W WIND 15 KT. SEAS 4 FT.
.TONIGHT...NW WIND 15 KT. SEAS 4 FT. FREEZING SPRAY.
.TUE...N WIND 20 KT. SEAS 4 FT. FREEZING SPRAY.
.TUE NIGHT...NW WIND 15 KT. SEAS 4 FT.
.WED...NW WIND 20 KT. SEAS 5 FT.
.THU...NW WIND 25 KT. SEAS 5 FT.
.FRI...N WIND 20 KT. SEAS 4 FT.

$$

PKZ139-210045-
COOK INLET KALGIN ISLAND TO POINT BEDE-
340 AM AKDT MON MAR 20 2017

...SMALL CRAFT ADVISORY TUESDAY...

.TODAY...VARIABLE WIND LESS THAN 10 KT BECOMING NE 10 KT IN THE
AFTERNOON. SEAS IN ICE FREE WATERS 3 FT.
.TONIGHT...N WIND 20 KT. SEAS IN ICE FREE WATERS 4 FT BUILDING TO
6 FT AFTER MIDNIGHT. FREEZING SPRAY.
.TUE...N WIND 25 KT. SEAS IN ICE FREE WATERS 6 FT. FREEZING SPRAY.
.TUE NIGHT...N WIND 20 KT. SEAS IN ICE FREE WATERS 4 FT.
.WED THROUGH FRI...N WIND 20 KT. SEAS IN ICE FREE WATERS 5 FT.

$$

PKZ140-210045-
COOK INLET NORTH OF KALGIN ISLAND-
340 AM AKDT MON MAR 20 2017

.TODAY...VARIABLE WIND LESS THAN 10 KT BECOMING NE 10 KT IN THE
AFTERNOON.
.TONIGHT...N WIND 10 KT.
.TUE...N WIND 10 KT BECOMING NE 15 KT IN THE AFTERNOON.
.TUE NIGHT...N WIND 20 KT.
.WED...N WIND 20 KT.
.THU THROUGH FRI...N WIND 10 KT.

$$

PKZ141-210045-
KACHEMAK BAY-
340 AM AKDT MON MAR 20 2017

.TODAY...VARIABLE WIND LESS THAN 10 KT BECOMING NW 10 KT IN THE
AFTERNOON. SEAS 2 FT.
.TONIGHT...N WIND 20 KT. SEAS 3 FT. FREEZING SPRAY.
.TUE...N WIND 20 KT. SEAS 2 FT. FREEZING SPRAY.
.TUE NIGHT...N WIND 20 KT. SEAS 2 FT.
.WED...N WIND 20 KT. SEAS 2 FT.
.THU THROUGH FRI...N WIND 15 KT. SEAS 2 FT.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
421 AM AKDT Sun Mar 19 2017

.ANALYSIS AND UPPER LEVELS...
A blocking upper level ridge remains in place over much of the
Bering. East of the ridge is a upper level low over the Southern
Mainland and Gulf, and to the west is another upper level low
southwest of the Western Aleutians. At the surface, low pressure
over the Northern Gulf continues to spread snow showers and gusty
winds around the Northern Gulf and Prince William Sound areas.
Otherwise, weak offshore flow and mostly clear and dry conditions
are being observed around the remainder of the Southern Mainland.
Out west, a strong surface low is evident southwest of the
Aleutians. The associated front stalled over the Eastern
Aleutians and western/central Bering has started to dissipate
over the area, resulting in showery and gusty conditions tapering
off.

&&

.MODEL DISCUSSION...
Models remain in good agreement through much of the short term
forecast. Some minor model differences appear in the Monday night
time frame regarding the timing of an upper level wave dropping
southward over the Susitna Valley and Cook inlet region. This
creates some uncertainty with the timing of when the stronger
winds will mix down from aloft, and where the core of strongest
winds will set up. Current guidance is showing the winds picking
up over these areas sometime Monday night. The NAM is showing the
strongest winds setting up mainly over Cook Inlet and Susitna
Valley. However, the GFS and EC are both showing the stronger
winds stretching southward from the Susitna Valley and further
eastward over Cook Inlet and the Western Kenai Coast. The NAM and
GFS were the preferred models for this forecast package, and a
middle ground blend was used for the above mentioned differences.

&&

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

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
The main weather concern today revolves around the low that has
moved into Western Prince William SOund overnight. This low is
farther north and west than models have been indication and that
is impacting the forecasts. Snow will likely persist in the
eastern portion of the Kenai Peninsula through today. There will
also be some snow showers bands making it into Kachemak Bay this
morning and a chance north of there in the western Kenai Peninsula
and northward toward Anchorage. It is still unlikely for Anchorage
to see any snowfall though a passing snow showers especially in
the morning cannot be rules out. North of Anchorage into the
Matanuska and Susitna Valleys there is not expected to be any
snowfall making it to the ground (though there could be a little
virga).

After today the snow should mostly pull out of the area into the
Gulf of Alaska except for the Cordova area. From Cordova eastward
there will be persistent southwest upper level flow into Monday or
Monday night and that will keep snow in the area through that
time.

Valdez is right on the edge of where there will be a bit of
snowfall with models generally trending for Cordova to have
greater amounts. However, with the more westerly progression of
the low overnight is could bring more persistent snowfall to
Valdez as well.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
Dry northerly flow between the Bering ridge and the mainland trough
will continue to yield cold, dry, and mostly clear conditions
across the southwest mainland through Tuesday morning.
Temperatures will begin to slowly trend upward (although still
remaining below seasonal normals) during the beginning of the week
as the ridge axis nudges eastward and the trough shifts farther
to the east over Southcentral AK.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
The front over the central Bering will continue to weaken in place
today and eventually dissipate as it encounters the ridge to the
east. This will bring improving conditions to the Pribilofs and
Eastern Aleutians as intermittent light snow showers come to an
end by the afternoon. Another front will move over the Western
and Central Aleutians this evening and bring rain and Small Craft
Advisory conditions to those parts of the chain through Monday
night. Meanwhile, the strong ridge over the eastern half of the
Bering will continue to support pleasant conditions marked by an
extended period of mostly sunny skies across the eastern half of
the Bering including the Alaska Peninsula.

&&

.LONG TERM FORECAST (Days 3 through 7)...
The southern mainland will continue with dry conditions
throughout the extended forecast as ridging dominates over the
central and eastern Bering. A slow warming trend can be expected
throughout next week as the polar jet weakens along the western
coast. The most active weather will focus in the western Bering
and Aleutians as a parent low near the Kamchatka Peninsula moves
several fronts up from the Pacific. Snow showers are also expected
to continue over the gulf as a weaker surface low becomes better
organized mid week due to a strong upper level wave progged to
dive from the arctic and re-invigorate the weakening low. The
biggest challenge for the next week is the anticipation of the
ridge breaking down as the subtropical jet migrates north. There
is still a bit of uncertainty on this evolution since model
consistency lacks from run to run. A blend of the ECMWF and GFS
ensembles were used for the extended range.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Gales...150 411.
         Heavy Freezing Spray...121 138 150 185.

&&

SYNOPSIS AND MODEL DISCUSSION...TP
SOUTHCENTRAL ALASKA...EZ
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...CB
LONG TERM...KH