Small Craft Advisory 997, NWS Anchorage, AK

777 
FZAK52 PAFC 161248
CWFALU

COASTAL WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE ALASKA
348 AM AKST FRI DEC 16 2016

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.

PKZ199-170130-
348 AM AKST FRI DEC 16 2016
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 953 MB LOW 300 NM SOUTHWEST OF SAINT MATTHEW ISLAND MOVES INTO
EASTERN RUSSIA BY LATE TONIGHT. ANOTHER 958 MB LOW 325 NM
SOUTHWEST OF ADAK MOVES TO 75 NM NORTHEAST OF ATKA AT 935 MB SAT
NIGHT.

$$

PKZ150-170130-
SOUTH OF THE AK PENINSULA SITKINAK TO CASTLE CAPE-
348 AM AKST FRI DEC 16 2016

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TODAY...S WIND 30 KT. SEAS 14 FT. RAIN.
.TONIGHT...SW WIND 30 KT. SEAS 16 FT. RAIN SHOWERS.
.SAT...W WIND 25 KT. SEAS 16 FT.
.SAT NIGHT...SE WIND 40 KT. SEAS 17 FT.
.SUN...SW WIND 40 KT. SEAS 25 FT.
.MON...SW WIND 35 KT. SEAS 27 FT.
.TUE...W WIND 25 KT. SEAS 24 FT.

$$

PKZ155-170130-
SOUTH OF THE AK PENINSULA CASTLE CAPE TO CAPE SARICHEF-
348 AM AKST FRI DEC 16 2016

...GALE WARNING SATURDAY...

.TODAY...SW WIND 30 KT. SEAS 18 FT. RAIN SHOWERS.
.TONIGHT...SW WIND 30 KT. SEAS 21 FT. RAIN SHOWERS.
.SAT...S WIND 25 KT BECOMING SE 45 KT IN THE AFTERNOON. FROM THE
SHUMAGIN ISLANDS E...SW WIND 25 KT BECOMING SE IN THE AFTERNOON.
SEAS 18 FT. RAIN.
.SAT NIGHT...S WIND 40 KT. SEAS 23 FT.
.SUN...SW WIND 45 KT. SEAS 33 FT.
.MON...SW WIND 40 KT. SEAS 34 FT.
.TUE...W WIND 25 KT. SEAS 24 FT.

$$

PKZ160-170130-
BRISTOL BAY-
348 AM AKST FRI DEC 16 2016

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TODAY...S WIND 25 KT. SEAS IN ICE FREE WATERS BUILDING TO 7 FT.
.TONIGHT...SW WIND 25 KT. SEAS IN ICE FREE WATERS 9 FT.
.SAT...SW WIND 20 KT. SEAS IN ICE FREE WATERS 7 FT. PATCHY FOG.
.SAT NIGHT...E WIND 40 KT. SEAS IN ICE FREE WATERS 9 FT.
.SUN...SE WIND 30 KT. SEAS IN ICE FREE WATERS 10 FT.
.MON...S WIND 20 KT. SEAS IN ICE FREE WATERS 8 FT.
.TUE...W WIND 15 KT. SEAS IN ICE FREE WATERS 6 FT.

$$

PKZ165-170130-
PORT HEIDEN TO CAPE SARICHEF-
348 AM AKST FRI DEC 16 2016

...GALE WARNING SATURDAY...

.TODAY...S WIND 30 KT. SEAS 13 FT BUILDING TO 19 FT IN THE
AFTERNOON. FROM PORT MOLLER E...SEAS 11 FT.
.TONIGHT...SW WIND 30 KT. SEAS 21 FT. RAIN SHOWERS.
.SAT...S WIND 20 KT BECOMING SE 35 KT IN THE AFTERNOON. FROM PORT
MOLLER E...SW WIND 20 KT BECOMING SE IN THE AFTERNOON. SEAS 19 FT.
.SAT NIGHT...SE WIND 40 KT. SEAS 14 FT.
.SUN...S WIND 30 KT. SEAS 19 FT.
.MON...S WIND 30 KT. SEAS 13 FT.
.TUE...W WIND 20 KT. SEAS 10 FT.

$$

PKZ170-170130-
CAPE SARICHEF TO NIKOLSKI BERING SIDE-
348 AM AKST FRI DEC 16 2016

...GALE WARNING THROUGH SATURDAY...

.TODAY...SW WIND 35 KT. SEAS 26 FT. RAIN SHOWERS.
.TONIGHT...SW WIND 35 KT. SEAS 26 FT.
.SAT...SE WIND 30 KT BECOMING E 45 KT IN THE AFTERNOON. SEAS 21
FT. WIDESPREAD RAIN SHOWERS.
.SAT NIGHT...S WIND 45 KT. SEAS 23 FT.
.SUN...SW WIND 45 KT. SEAS 26 FT.
.MON...SW WIND 35 KT. SEAS 14 FT.
.TUE...W WIND 25 KT. SEAS 13 FT.

$$

PKZ171-170130-
UNALASKA BAY-
348 AM AKST FRI DEC 16 2016

...GALE WARNING SATURDAY...

.TODAY...SW WIND 25 KT. SEAS 4 FT. RAIN SHOWERS.
.TONIGHT...SW WIND 25 KT. SEAS 4 FT.
.SAT...SE WIND 20 KT BECOMING E 40 KT IN THE AFTERNOON. SEAS 3 FT
BUILDING TO 6 FT IN THE AFTERNOON. RAIN.
.SAT NIGHT...S WIND 35 KT. SEAS 5 FT.
.SUN...SW WIND 35 KT. SEAS 5 FT.
.MON...SW WIND 25 KT. SEAS 4 FT.
.TUE...W WIND 20 KT. SEAS 2 FT.

$$

PKZ172-170130-
CAPE SARICHEF TO NIKOLSKI PACIFIC SIDE-
348 AM AKST FRI DEC 16 2016

...GALE WARNING THROUGH SATURDAY...

.TODAY...SW WIND 35 KT. SEAS 26 FT. RAIN SHOWERS.
.TONIGHT...W WIND 35 KT. SEAS 26 FT.
.SAT...SE WIND 45 KT. SEAS 19 FT. WIDESPREAD RAIN SHOWERS.
.SAT NIGHT...SW WIND 50 KT. SEAS 44 FT.
.SUN...SW WIND 55 KT. SEAS 40 FT.
.MON...SW WIND 40 KT. SEAS 35 FT.
.TUE...W WIND 25 KT. SEAS 20 FT.

$$

PKZ173-170130-
NIKOLSKI TO SEGUAM ISLAND BERING SIDE-
348 AM AKST FRI DEC 16 2016

...STORM WARNING SATURDAY...

.TODAY...SW WIND 40 KT. SEAS 28 FT. RAIN SHOWERS.
.TONIGHT...W WIND 35 KT BECOMING S 25 KT AFTER MIDNIGHT. SEAS 27
FT.
.SAT...SE WIND 50 KT. SEAS 20 FT. RAIN.
.SAT NIGHT...S WIND 50 KT. SEAS 30 FT.
.SUN...W WIND 50 KT. SEAS 34 FT.
.MON...W WIND 35 KT. SEAS 16 FT.
.TUE...W WIND 25 KT. SEAS 14 FT.

$$

PKZ174-170130-
NIKOLSKI TO SEGUAM ISLAND PACIFIC SIDE-
348 AM AKST FRI DEC 16 2016

...STORM WARNING SATURDAY...

.TODAY...SW WIND 40 KT. SEAS 36 FT. WIDESPREAD RAIN SHOWERS.
.TONIGHT...SW WIND 35 KT BECOMING S 25 KT AFTER MIDNIGHT. SEAS 28
FT SUBSIDING TO 22 FT AFTER MIDNIGHT.
.SAT...SE WIND 50 KT. SEAS 23 FT. RAIN.
.SAT NIGHT...SW WIND 60 KT. SEAS 51 FT.
.SUN...SW WIND 60 KT. SEAS 46 FT.
.MON...W WIND 40 KT. SEAS 32 FT.
.TUE...W WIND 30 KT. SEAS 19 FT.

$$

PKZ175-170130-
SEGUAM ISLAND TO ADAK BERING SIDE-
348 AM AKST FRI DEC 16 2016

...STORM WARNING SATURDAY...

.TODAY...SW WIND 45 KT. SEAS 32 FT. RAIN SHOWERS.
.TONIGHT...SW WIND 40 KT BECOMING S 30 KT AFTER MIDNIGHT. SEAS 27
FT SUBSIDING TO 21 FT AFTER MIDNIGHT. RAIN.
.SAT...SE WIND 55 KT. SEAS 20 FT. WIDESPREAD RAIN SHOWERS.
.SAT NIGHT...W WIND 55 KT. SEAS 19 FT.
.SUN...W WIND 55 KT. SEAS 26 FT.
.MON...W WIND 30 KT. SEAS 14 FT.
.TUE...W WIND 25 KT. SEAS 13 FT.

$$

PKZ176-170130-
SEGUAM ISLAND TO ADAK PACIFIC SIDE-
348 AM AKST FRI DEC 16 2016

...HURRICANE FORCE WIND WARNING SATURDAY...

.TODAY...W WIND 45 KT. SEAS 37 FT.
.TONIGHT...SW WIND 30 KT BECOMING SE 40 KT AFTER MIDNIGHT. SEAS
26 FT SUBSIDING TO 18 FT AFTER MIDNIGHT. RAIN.
.SAT...SE WIND 50 KT BECOMING SW 70 KT IN THE AFTERNOON. SEAS 23
FT BUILDING TO 41 FT IN THE AFTERNOON. WIDESPREAD RAIN SHOWERS.
.SAT NIGHT...W WIND 70 KT. SEAS 52 FT.
.SUN...W WIND 60 KT. SEAS 46 FT.
.MON...W WIND 35 KT. SEAS 24 FT.
.TUE...W WIND 30 KT. SEAS 18 FT.

$$

PKZ177-170130-
ADAK TO KISKA-
348 AM AKST FRI DEC 16 2016

...HURRICANE FORCE WIND WARNING SATURDAY...

.TODAY...W WIND 50 KT. SEAS 37 FT. WIDESPREAD RAIN SHOWERS.
.TONIGHT...SW WIND 35 KT BECOMING SE 45 KT AFTER MIDNIGHT. SEAS
24 FT SUBSIDING TO 18 FT AFTER MIDNIGHT. RAIN.
.SAT...BERING SIDE...NE WIND 50 KT. SEAS 17 FT. PAC SIDE...SE WIND
50 KT BECOMING W 70 KT IN THE AFTERNOON...SEAS 21 FT BUILDING TO
38 FT IN THE AFTERNOON. WIDESPREAD RAIN SHOWERS.
.SAT NIGHT...W WIND 65 KT. SEAS 37 FT.
.SUN...W WIND 50 KT. SEAS 34 FT.
.MON THROUGH TUE...W WIND 30 KT. SEAS 17 FT.

$$

PKZ178-170130-
KISKA TO ATTU-
348 AM AKST FRI DEC 16 2016

...STORM WARNING TODAY AND SATURDAY...

.TODAY...W WIND 50 KT. SEAS 35 FT.
.TONIGHT...SW WIND 35 KT BECOMING S 25 KT AFTER MIDNIGHT. SEAS 23
FT SUBSIDING TO 16 FT AFTER MIDNIGHT. RAIN SHOWERS.
.SAT...BERING SIDE...N WIND 30 KT BECOMING NW 45 KT IN THE
AFTERNOON...SEAS 15 FT. PAC SIDE...W WIND 55 KT...SEAS 17 FT
BUILDING TO 25 FT IN THE AFTERNOON. RAIN SHOWERS.
.SAT NIGHT...NW WIND 50 KT. SEAS 22 FT.
.SUN...NW WIND 35 KT. SEAS 21 FT.
.MON...NW WIND 25 KT. SEAS 16 FT.
.TUE...W WIND 30 KT. SEAS 14 FT.

$$

PKZ179-170130-
PRIBILOF ISLANDS NEAR SHORE WATERS-
348 AM AKST FRI DEC 16 2016

...GALE WARNING THROUGH TONIGHT...

.TODAY...SW WIND 40 KT. SEAS 27 FT. WIDESPREAD RAIN SHOWERS.
.TONIGHT...SW WIND 35 KT. SEAS 27 FT. RAIN SHOWERS AND SNOW
SHOWERS.
.SAT...SE WIND 30 KT. SEAS 22 FT. PATCHY FOG.
.SAT NIGHT...E WIND 45 KT. SEAS 18 FT.
.SUN...E WIND 35 KT. SEAS 20 FT.
.MON...N WIND 20 KT. SEAS 11 FT.
.TUE...W WIND 15 KT. SEAS 8 FT.

$$

PKZ180-170130-
KUSKOKWIM DELTA AND ETOLIN STRAIT-
348 AM AKST FRI DEC 16 2016

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TODAY...S WIND 30 KT. SEAS IN ICE FREE WATERS 13 FT.
.TONIGHT...S WIND 25 KT. SEAS IN ICE FREE WATERS 14 FT.
.SAT...SW WIND 20 KT. SEAS IN ICE FREE WATERS 14 FT.
.SAT NIGHT...E WIND 40 KT. SEAS IN ICE FREE WATERS 12 FT.
.SUN...E WIND 35 KT. SEAS IN ICE FREE WATERS 14 FT.
.MON...SE WIND 25 KT. SEAS IN ICE FREE WATERS 11 FT.
.TUE...NW WIND 20 KT. SEAS IN ICE FREE WATERS 6 FT.

$$

PKZ181-170130-
NORTH AND WEST OF NUNIVAK ISLAND-
348 AM AKST FRI DEC 16 2016

...GALE WARNING TODAY...

.TODAY...SE WIND 35 KT. SEAS IN ICE FREE WATERS 16 FT. PATCHY FOG.
.TONIGHT...S WIND 30 KT. SEAS IN ICE FREE WATERS 16 FT. PATCHY FOG.
.SAT...SW WIND 25 KT. SEAS IN ICE FREE WATERS 15 FT. PATCHY
FOG.
.SAT NIGHT...E WIND 30 KT. SEAS IN ICE FREE WATERS 10 FT.
.SUN...NE WIND 30 KT. SEAS IN ICE FREE WATERS 9 FT.
.MON...NE WIND 20 KT. SEAS IN ICE FREE WATERS 6 FT.
.TUE...N WIND 15 KT. SEAS IN ICE FREE WATERS 5 FT.

$$

PKZ185-170130-
SAINT MATTHEW ISLAND WATERS-
348 AM AKST FRI DEC 16 2016

...GALE WARNING THROUGH TONIGHT...

.TODAY...SE WIND 40 KT. SEAS 24 FT. WIDESPREAD RAIN SHOWERS.
.TONIGHT...S WIND 35 KT E OF SAINT MATTHEW ISLAND...SW 40 KT W OF
SAINT MATTHEW ISLAND. SEAS 25 FT.
.SAT...SW WIND 30 KT. SEAS 24 FT.
.SAT NIGHT...E WIND 30 KT. SEAS 15 FT.
.SUN...NE WIND 35 KT. SEAS 15 FT.
.MON...N WIND 25 KT. SEAS 9 FT.
.TUE...N WIND 20 KT. SEAS 9 FT.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
501 AM AKST Thu Dec 15 2016

.ANALYSIS AND UPPER LEVELS...
The main feature anchoring the flow pattern aloft is a complex low
center over Kamchatka this morning. An active 160 kt jet is
entering the base of the trough toward the western Aleutians. A
high amplitude/narrow ridge extends from the mid-latitude
northward over the mainland, and up into the arctic. Between these
two features is a washed-out front over the southwest mainland and
a trough to the west of the front, left over from the previous
upper low pressure. A vigorous shortwave trough is entering the
Kamchatka upper low, underneath the east Asian jet, and looks to
be the driver of active weather in the next couple days.

Sensible weather-wise, ridging over southcentral Alaska continues
to promote high pressure, clear sky, and frigid temperatures in
the Copper River Basin. The Cook Inlet region is mostly clear as
well, but some low stratus and patchy fog has formed around Knik
Arm and the Anchorage Bowl. The weakening front is bringing spotty
rain to the southwest mainland, while the next front out west is
beginning to impact the central Aleutians with rain and a solid
gale-force front.

&&

.MODEL DISCUSSION...
Once again, synoptics are well agreed upon, but the devil is in
the details. The first problem is a shortwave trough that will
progress from the southwest to the southcentral today. Orientation
and timing are pretty close, but strength and QPF are not well
agreed upon. The common theme to focus on is a quick shot of snow
this afternoon and evening with minor accumulation in most areas
around the Cook Inlet region.

Over the weekend, there is decent agreement on the aforementioned
trough, now entering the western Aleutians, bringing another shot
of snow to the region. The key with that storm will be upper
trough and surface low position, but right now moderate
accumulations look possible.

.AVIATION...
PANC...low stratus could persist longer than forecast as there is
no mechanism to mix it out. Upper ridging moving off to the east
should prevent the bank from growing too much larger, but light
winds and clear sky above, and low/late rising sun above could
promote a longer-lived deck.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
Fog formed over the Anchorage bowl last evening, but expect it
to dissipate this morning as the upper ridge slides eastward and
clouds move in from the southwest. Weak isentropic lift will
develop in the mid to late afternoon hours, leading to lowering
clouds and flurries or light snow in the Cook Inlet region. Snow
will then become steadier and increase in intensity as an upper
level short-wave arrives during the evening hours. The wave does
sharpen slightly as it arrives, so have upped snow amounts from
previous forecast by about an inch. Overall, still only expecting
2 or 3 inches for most places in the Cook Inlet region. As the air
mass continues to warm expect snow to change to rain along the
southwest Kenai Peninsula by this evening. Meanwhile, snow will
continue to overspread most of the rest of Southcentral during
the overnight hours.

Another system will be fast on the heels of this first one, so
expect very little break. In fact, models are all keying on
another area of isentropic lift right behind the first short-
wave. This will bring some additional light precip to the Cook
Inlet to Susitna Valley corridor late tonight through Friday. Flow
will begin to back toward the southeast and strengthen ahead of
the next upper trough and surface front, so areas in the lee of
the Kenai and Chugach will dry out. A steady supply of warm air
advection, combined with downslope warming, will lead to a mix
of precip types Friday through Friday Night. Although there may
initially be some freezing rain as air above the surface warms,
do not expect it to last very long or cause any significant
problems. Looks like above freezing temps will make it is far
north as Anchorage and possibly all the way to southern portions
of the Mat-Su valleys by late Friday night. Downsloping will keep
much of this area dry, but do expect rain to fall across portions
of the Kenai Peninsula.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
Warmer air has already begun to displace the cold air mass that
has been entrenched across the region for the past couple of
weeks. Most locations have warmed up to the freezing mark with
just some locations in the Kuskokwim Valley holding onto colder
temperatures. These warmer temperatures should remain nearly
constant through Friday under cloudy conditions, then begin to
cool off again as colder air aloft advects from the west on Friday
afternoon. Snow and rain will begin to taper off into more of a
widespread showery regime this morning as the upper level wave
continues to weaken and push further eastward. There is some
potential for fog to develop this morning over low lying areas, as
the surface inversion strengthens from the warm air advection and
a push of moisture across the region.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
The active weather pattern across the Bering Sea will continue
into the weekend. A strong area of low pressure over the far
western Aleutians will quickly track northward into the Western
Bering this evening, wrapping around a good amount of colder air
over the western Aleutians. The strongest winds from this system
will be observed along this area of colder air advecting over the
Western Aleutians later this morning through early Friday morning.
Ahead of the low, the initial front will quickly spread eastward
across the Central and Eastern Aleutians/Bering, and produce gale
to storm force winds with periods of moderate to heavy rainfall.
In addition, very impressive sea heights of 45 to 50 ft are
expected as a very favorable fetch and low level jet will provide
favorable conditions for seas to build. The highest seas are
expected over thew Western Aleutians and then the Pacific side of
the Aleutian Chain. Sea of 30 to 40 ft will be likely over the
eastern half of the Bering Sea on Friday.

&&

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

A pattern change remains on track beginning this weekend. An
approaching zonal jet will slam into the the ridge over mainland
AK on Sat, causing the ridge to weaken and move rapidly east. A
developing low pressure system in the Gulf will swing a front up
against the coast on Saturday bringing accumulating snow to most
of Southcentral Alaska. The Prince William Sound low looks to be
in a good position along with the upper trough to our west, with
cold advection up the Inlet. All signs of a classic accumulating
snow for the Anchorage area. However details can change between
now and then, stay tuned. While this is happening, a stacked low
pressure system dissipates over the northwest Bering. This low
will transfer energy to a new north Pacific low that moves with
the jet along the Alaska Peninsula to the Gulf of AK Sun into Mon.
The collapse of the blocking ridge will allow several systems
associated with the zonal jet to rapidly move along the AKpen and
into the Gulf of Alaska through mid week.

This will bring a moderating trend to temperatures to all of our
area of responsibility, as well as increased precipitation
chances, especially along the coastlines. Trends suggest there may
be ample snow opportunities inland by early next week as well.

For the Bering specifically, the main impacts will be strong
winds given the decent jet energy with the low pressure systems
and their associated fronts.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Hurricane 178.
         Storm 170 172 173 174 175 176 177 179 185.
         Gale 132 150 155 165 171 180 181.

&&

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