Small Craft Advisory 901, NWS Anchorage, AK

808 
FZAK52 PAFC 271308
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
408 AM AKST Mon Nov 27 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.

PKZ199-280200-
408 AM AKST Mon Nov 27 2017
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...
A 959 mb low 110 nm northwest of Cold Bay will move into the 
western Gulf by Mon afternoon at 971 mb. A second 979 mb North 
Pacific low 70 nm southeast of Shemya will move to 160 nm
northeast of Adak at 959 mb by this afternoon, then move to 160 
nm east of St. George Island at 950 mb by Wed morning. A third low
at 947 mb will move to 95 nm southeast of Sand Point by Tue 
afternoon, before getting absorbed into the second low at 160 nm 
northeast of Adak. 

$$

PKZ150-280200-
South of the AK Peninsula Sitkinak to Castle Cape-
408 AM AKST Mon Nov 27 2017

...STORM WARNING TUESDAY...

.TODAY...S wind 35 kt becoming SW 45 kt in the afternoon. Seas
30 ft. Rain showers.
.TONIGHT...W wind 35 kt. Seas 29 ft subsiding to 20 ft after
midnight.
.TUE...SE wind 50 kt. Seas 18 ft building to 26 ft in the
afternoon. Rain showers.
.TUE NIGHT...S wind 40 kt. Seas 30 ft.
.WED...S wind 35 kt. Seas 28 ft.
.THU...NW wind 30 kt. Seas 25 ft.
.FRI...SW wind 25 kt. Seas 16 ft.

$$

PKZ155-280200-
South of the AK Peninsula Castle Cape to Cape Sarichef-
408 AM AKST Mon Nov 27 2017

...STORM WARNING TODAY...

.TODAY...W wind 60 kt diminishing to 50 kt in the afternoon. From
the Shumagin Islands E, W wind 55 kt. Seas 40 ft.
.TONIGHT...S wind 40 kt. From the Shumagin Islands E, SW wind 
30 kt becoming S 40 kt after midnight. Seas 23 ft. Rain showers.
.TUE...SW wind 45 kt. Seas 21 ft building to 33 ft in the
afternoon. Rain showers.
.TUE NIGHT...SW wind 45 kt. Seas 36 ft.
.WED...SW wind 40 kt. Seas 32 ft.
.THU...W wind 35 kt. Seas 21 ft.
.FRI...SW wind 30 kt. Seas 18 ft.

$$

PKZ160-280200-
Bristol Bay-
408 AM AKST Mon Nov 27 2017

...GALE WARNING TUESDAY...

.TODAY...E wind 30 kt. Seas 9 ft.
.TONIGHT...SE wind 15 kt increasing to 30 kt after midnight. 
Seas 7 ft.
.TUE...SE wind 35 kt becoming E 45 kt in the afternoon. 
Seas 10 ft.
.TUE NIGHT...SE wind 45 kt. Seas 10 ft.
.WED...E wind 25 kt. Seas 6 ft.
.THU...NW wind 20 kt. Seas 5 ft.
.FRI...S wind 20 kt. Seas 7 ft.

$$

PKZ165-280200-
Port Heiden to Cape Sarichef-
408 AM AKST Mon Nov 27 2017

...GALE WARNING TODAY AND TUESDAY...

.TODAY...W wind 45 kt diminishing to 35 kt in the afternoon. From
Port Moller E, S wind 15 kt becoming W 25 kt in the afternoon.
Seas 24 ft except 14 ft from Port Moller E.
.TONIGHT...SE wind 30 kt. From Port Moller E, S wind 20 kt
becoming SE 30 kt after midnight. Seas 14 ft. Rain.
.TUE...S wind 30 kt diminishing to 20 kt in the afternoon. From
Port Moller E, SE wind 35 kt. Seas 10 ft. Rain showers.
.TUE NIGHT...S wind 25 kt. Seas 11 ft.
.WED...NE wind 30 kt. Seas 11 ft.
.THU...W wind 30 kt. Seas 12 ft.
.FRI...S wind 25 kt. Seas 12 ft.

$$

PKZ170-280200-
Cape Sarichef to Nikolski Bering Side-
408 AM AKST Mon Nov 27 2017

...STORM WARNING TODAY...

.TODAY...W wind 55 kt becoming S 30 kt in the afternoon. 
Seas 37 ft subsiding to 21 ft in the afternoon. Rain.
.TONIGHT...S wind 35 kt. Seas 17 ft. Rain.
.TUE...SW wind 40 kt. Seas 21 ft. Rain showers.
.TUE NIGHT...W wind 40 kt. Seas 21 ft.
.WED...NW wind 45 kt. Seas 22 ft.
.THU THROUGH FRI...SW wind 30 kt. Seas 17 ft.

$$

PKZ171-280200-
Unalaska Bay-
408 AM AKST Mon Nov 27 2017

...STORM WARNING TODAY...

.TODAY...W wind 55 kt becoming SW 15 kt in the afternoon. 
Seas 9 ft subsiding to 2 ft in the afternoon. Rain.
.TONIGHT...S wind 30 kt. Seas 4 ft. Rain.
.TUE...SW wind 30 kt. Seas 5 ft. Rain showers.
.TUE NIGHT...W wind 30 kt. Seas 5 ft.
.WED...NW wind 30 kt. Seas 13 ft.
.THU...SW wind 30 kt. Seas 10 ft.
.FRI...SW wind 25 kt. Seas 3 ft.

$$

PKZ172-280200-
Cape Sarichef to Nikolski Pacific Side-
408 AM AKST Mon Nov 27 2017

...STORM WARNING TODAY AND TUESDAY...

.TODAY...W wind 60 kt becoming SW 40 kt in the afternoon. 
Seas 37 ft subsiding to 25 ft in the afternoon. Rain showers.
.TONIGHT...SW wind 45 kt. Seas 24 ft. Rain.
.TUE...W wind 60 kt diminishing to 50 kt in the afternoon. 
Seas 31 ft building to 39 ft in the afternoon. Rain showers.
.TUE NIGHT...W wind 50 kt. Seas 36 ft.
.WED...W wind 50 kt. Seas 33 ft.
.THU...SW wind 35 kt. Seas 18 ft.
.FRI...SW wind 30 kt. Seas 20 ft.

$$

PKZ173-280200-
Nikloski to Seguam Island Bering Side-
408 AM AKST Mon Nov 27 2017

...HURRICANE FORCE WIND WARNING TONIGHT AND TUESDAY...

.TODAY...SW wind 40 kt. Seas 29 ft subsiding to 18 ft in the
afternoon. Rain showers.
.TONIGHT...SW wind 30 kt becoming NW 65 kt after midnight. Seas 16 
ft building to 28 ft after midnight. Rain showers.
.TUE...NW wind 65 kt becoming W 50 kt in the afternoon. Seas 30 ft. 
Rain showers.
.TUE NIGHT...W wind 50 kt. Seas 31 ft.
.WED...NW wind 50 kt. Seas 32 ft.
.THU...SW wind 35 kt. Seas 19 ft.
.FRI...SW wind 30 kt. Seas 17 ft.

$$

PKZ174-280200-
Nikolski to Seguam Island Pacific Side-
408 AM AKST Mon Nov 27 2017

...HURRICANE FORCE WIND WARNING TONIGHT AND TUESDAY...

.TODAY...SW wind 45 kt. Seas 30 ft. Rain showers.
.TONIGHT...SW wind 55 kt becoming N 65 kt after midnight. Gusts to 80
kt out of bays and passes after midnight. Seas 24 ft building to 
33 ft after midnight. Rain showers.
.TUE...N wind 65 kt becoming W 50 kt in the afternoon. Gusts to 80 kt
out of bays and passes through the morning. Seas 38 ft. 
Rain showers.
.TUE NIGHT...W wind 50 kt. Seas 35 ft.
.WED...W wind 55 kt. Seas 36 ft.
.THU...SW wind 35 kt. Seas 20 ft.
.FRI...SW wind 30 kt. Seas 22 ft.

$$

PKZ175-280200-
Seguam Island to Adak Bering Side-
408 AM AKST Mon Nov 27 2017

...HURRICANE FORCE WIND WARNING TONIGHT AND TUESDAY...

.TODAY...S wind 30 kt becoming SW 60 kt in the afternoon. 
Seas 20 ft. Rain showers.
.TONIGHT...N wind 65 kt. Seas 29 ft. Rain showers and snow
showers.
.TUE...NW wind 65 kt diminishing to 45 kt in the afternoon. 
Seas 29 ft. Rain showers and snow showers.
.TUE NIGHT...NW wind 50 kt. Seas 29 ft.
.WED...W wind 50 kt. Seas 30 ft.
.THU...SW wind 30 kt. Seas 15 ft.
.FRI...SW wind 35 kt. Seas 17 ft.

$$

PKZ176-280200-
Seguam Island to Adak Pacific Side-
408 AM AKST Mon Nov 27 2017

...HURRICANE FORCE WIND WARNING TONIGHT AND TUESDAY...

.TODAY...SW wind 45 kt. Seas 24 ft. Rain showers.
.TONIGHT...NW wind 65 kt. Gusts to 80 kt out of bays and passes.
Seas 27 ft building to 33 ft after midnight. Rain showers with snow 
showers.
.TUE...NW wind 65 kt becoming W 50 kt in the afternoon. Gusts to 80
kt out of bays and passes through late morning. Seas 35 ft. Rain 
showers and snow showers.
.TUE NIGHT...W wind 50 kt. Seas 29 ft.
.WED...W wind 50 kt. Seas 27 ft.
.THU...SW wind 35 kt. Seas 21 ft.
.FRI...SW wind 30 kt. Seas 22 ft.

$$

PKZ177-280200-
Adak to Kiska-
408 AM AKST Mon Nov 27 2017

...STORM WARNING THROUGH TONIGHT...

.TODAY...W wind 35 kt becoming NW 60 kt in the afternoon. 
Seas 21 ft. Rain showers with snow showers.
.TONIGHT...NW wind 60 kt. Seas 26 ft. Snow showers.
.TUE...NW wind 45 kt. Seas 26 ft. Snow showers.
.TUE NIGHT...NW wind 45 kt. Seas 25 ft.
.WED THROUGH FRI...SW wind 40 kt. Seas 22 ft.

$$

PKZ178-280200-
Kiska to Attu-
408 AM AKST Mon Nov 27 2017

...GALE WARNING THROUGH TUESDAY...

.TODAY...N wind 40 kt. Seas 22 ft.
.TONIGHT...NW wind 40 kt. Seas 21 ft. Snow showers.
.TUE...NW wind 40 kt. Seas 23 ft. Snow showers.
.TUE NIGHT...NW wind 35 kt. Seas 21 ft.
.WED...SW wind 35 kt. Seas 16 ft.
.THU THROUGH FRI...SW wind 40 kt. Seas 28 ft.

$$

PKZ179-280200-
Pribilof Islands Near Shore Waters-
408 AM AKST Mon Nov 27 2017

...GALE WARNING TONIGHT...

.TODAY...NW wind 20 kt in the morning becoming variable 10 kt.
Seas 14 ft. Rain showers.
.TONIGHT...SE wind 35 kt. Seas 12 ft. Rain.
.TUE...NE wind 25 kt. Seas 12 ft.
.TUE NIGHT...N wind 35 kt. Seas 13 ft.
.WED...N wind 35 kt. Seas 15 ft.
.THU...SW wind 30 kt. Seas 13 ft.
.FRI...SW wind 25 kt. Seas 15 ft.

$$

PKZ180-280200-
Kuskokwim Delta and Etolin Strait-
408 AM AKST Mon Nov 27 2017

...GALE WARNING TONIGHT AND TUESDAY...

.TODAY...NE wind 25 kt diminishing to 10 kt in the afternoon. 
Seas 10 ft.
.TONIGHT...SE wind 20 kt increasing to 35 kt after midnight. 
Seas 10 ft.
.TUE...E wind 40 kt. Seas 13 ft. Snow with rain.
.TUE NIGHT...E wind 40 kt. Seas 13 ft.
.WED...NE wind 25 kt. Seas 9 ft.
.THU...W wind 30 kt. Seas 7 ft.
.FRI...S wind 30 kt. Seas 12 ft.

$$

PKZ181-280200-
North and West of Nunivak Island-
408 AM AKST Mon Nov 27 2017

...GALE WARNING TUESDAY...
...HEAVY FREEZING SPRAY WARNING TUESDAY...

.TODAY...NE wind 25 kt. Seas 9 ft.
.TONIGHT...E wind 15 kt increasing to 30 kt after midnight. 
Seas 7 ft. Freezing spray.
.TUE...E wind 35 kt. Seas 11 ft. Heavy freezing spray. Snow and
rain.
.TUE NIGHT...NE wind 30 kt. Seas 10 ft.
.WED...N wind 25 kt. Seas 9 ft.
.THU THROUGH FRI...S wind 35 kt. Seas 10 ft.

$$

PKZ185-280200-
Saint Matthew Island Waters-
408 AM AKST Mon Nov 27 2017

...GALE WARNING TUESDAY...

.TODAY...NE wind 25 kt. Seas 13 ft. Freezing spray. Snow showers.
.TONIGHT...NE wind 25 kt. Seas 11 ft. Freezing spray.
.TUE...NE wind 35 kt. Seas 12 ft. Freezing spray.  and rain.
.TUE NIGHT...NE wind 30 kt. Seas 12 ft.
.WED...N wind 25 kt. Seas 10 ft.
.THU THROUGH FRI...S wind 30 kt. Seas 13 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
507 AM AKST Sun Nov 26 2017

.ANALYSIS AND UPPER LEVELS...
The most significant feature over the forecast area is a
deepening low pressure system spreading across much of the Bering
Sea and Aleutian chain. This low has intensified significantly and
is causing northerly hurricane force winds throughout the Central
Bering and Aleutians. Hurricane force winds are already being
observed over Adak at 89 mph and continue to increase. Current
scatterometer data has also been observed, showing 70 mph winds
throughout the Western Bering and shifting eastward while
intensifying. The winds are being supported by an upper level jet
streak with wind speeds near 150 mph with the low sitting in the
upper-left exit region. Showery precipitation has also been
reported on the backside of the low in the Western/Central
Aleutians and is mostly falling as rain. The associated front is
moving toward the Kuskokwim Delta Coast and Bristol Bay bringing
snowfall and increasing winds to the coastline.

While not as strong as the storm in the Bering, there is a
weakening low in the Northern Gulf which brought 4 inches of snow
to Cordova yesterday. The weak wave on the northern periphery of
the system that produced the above mentioned snowfall, continues
to track westward through Prince William Sound while weakening.

&&

.MODEL DISCUSSION...
The biggest model question for the past few days is the behavior
of the intense Bering Sea low after it moves into Bristol Bay
tonight into Monday. The ECMWF and Canadian models began to shift
the low farther south and across the Alaska Peninsula with
another strengthening low in the vicinity of Adak on Monday.
Whereas the American models continue to trend toward the
EC/Canadian solution with each passing model run. This agreement
continues to raise confidence that there will be little, if any,
coastal flooding in the Kuskokwim Delta and Bristol Bay as the
track of the low and subsequent weakening of it are not conducive
for flooding.

The north Gulf coast also has a bit of a change that the models
are currently working out. The weak low tracking westward over the
northern Gulf from the east is moving faster and progressing
farther west than the models have been showing. This system is
expected to bringing some snow over the eastern Kenai this today,
with a very small chance of bringing some snow flurries as far
west as Anchorage.

&&

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

&&
.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
The low over the northern Gulf (and associated snow showers) will
continue a slow westward track today. The low level flow is in
opposition to the upper level flow, so have slowed down the
arrival of snow showers in western Prince William Sound. With
weaker advection, it looks less and less likely that any snow will
make it over the Chugach and Kenai Mountains. Cold and dry air in
place would likely lead to evaporation of snow before it reaches
the ground anyway. Contrary to this, have upped the likelihood of
snow over the Susitna Valley this afternoon and evening as an
upper low over Fairbanks area tracks westward, with potential for
some weak lift on the south side of the low to interact with mid
level moisture moving in from the northern Gulf. In any case, any
snow that does fall in the Susitna Valley will be very light.

The focus for upcoming days is on the deep Bering Sea low, which
is setting up a change in pattern from the cold dry and windy
weather we've seen of late to warmer and "wetter" weather. The
first sign of this change will be a trough and surface front
headed to Kodiak Island today. This is on track to bring light
snow accumulation to the island before transitioning to rain this
afternoon and evening. The upper trough becomes fairly diffuse as
it continues northward toward Southcentral, so expect the bulk of
precip to be confined to the coastal zone. More specifically, low
level southeasterly flow will enhance snow amounts over western
Prince William Sound and the west side of Cook Inlet on Monday.
Precipitation type will remain mostly snow, with the possibility
of mixed precip along the immediate coast by Monday afternoon.
Meanwhile, inland areas will stay mostly dry, but cloud cover and
weak warm air advection will lead to moderation of temperatures.

&&

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

Snow continues to push inland early this morning, accompanied by
gusty winds. Some observations have approached blizzard criteria
at times, but this threat looks to be limited both temporally and
spatially enough to preclude any upgrade to the current
headlines. Otherwise, as a strong ~941 mb low continues to slow
its progression as it nears the Pribilof Islands, and the
associated surface front occludes west of a Bethel to King Salmon
line. Areas of light to moderate snow are developing along and
immediately behind the front.

As the low begins to fill (become vertically stacked and weaken)
this evening and overnight, precipitation will become lighter and
more showery in nature. This low will emerge into the Gulf of
Alaska by Monday evening, another rapidly strengthening low will
undergo bombogenesis (strengthening at least 20 mb in 24 hours),
as it moves from near Shemya at 980 mb around midnight tonight to
~941 mb once again in a similar location to the current storm. It
too will send another front inland across southwest Alaska.
However, this time around though temperatures in the lowest few
thousand feet will have warmed enough for any precipitation to be
of the liquid variety.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...

The much advertised storm is well underway, with gusts having
topped 90 mph early this morning. Some gusts will likely top 100
mph, with perhaps a few gusts getting near 120mph. This is quite
a storm with waves forecast near 55 mph, and even a secondary
vort diving southeast on the backside of the low having produced a
squall lien with abundant lightning south of the chain.

A prolonged period of windy conditions will continue through
Monday morning, as several vort maxes rotate around the low and
help mix down the winds aloft given the low PV (potential
vorticity) heights and the degree of cold advection associated
with this system. Snow levels will be low enough for some
accumulating snow to occur along western and central portions of
the Aleutians. This storm will weaken overnight tonight into
Monday as it slides off to the southeast. However, another rapidly
deepening low will approach the region as described above, with
more hurricane force winds likely somewhere in the Monday night
through Tuesday time frame.

&&

.LONG TERM FORECAST (Days 3 through 7)...
Forecast confidence in the long-term is fairly low at this point,
due to the run to run variation in the models over the past few
days. The overall change in the pattern from a clear. dry pattern
for the mainland to a warmer, stormier pattern still stands, but
the exact timing and effects of the low pressure systems seems to
change from model to model on a run to run basis.

Current thinking is that a low will rapidly develop into a storm-
force system in the Bering Sea on Tuesday, bringing high winds
once again to the Aleutians. This low is expected to develop a
secondary low south of the AK Pen, pushing a strong front into
South Central Tuesday night into Wednesday. A lot of warm air is
associated with this front, which will cause some challenges with
forecasting precipitation type, in particular in the Bristol Bay
and Kenai Peninsula regions. High winds with the front may move
through Southcentral -- although current model runs are slightly
weaker than yesterday.

After Wednesday, another front moves into the Western Bering on
Thursday and begins to cross the Bering Sea. Although this
indicates a continued stormy pattern, the timing and strength of
this system is highly variable between model solutions, so
confidence in current specifics of the forecast remains low.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...High Wind Warning 185 187.
         Winter Weather Advisory 155 161.
MARINE...Hurricane Force Wind Warning 170 172-176 413.
         Storm Warning 155 160 171 177 180 181 185.
         Gale Warning 119 127 130 150 165 178 179.
         Heavy Freezing Spray Warning 160 181.

&&

SYNOPSIS AND MODEL DISCUSSION...TP/RA
SOUTHCENTRAL ALASKA...SEB
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...PD
LONG TERM...LF

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
122 PM AKST SUN NOV 26 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1058 AM     NON-TSTM WND GST UNALASKA                53.93N 166.51W
11/26/2017  M91 MPH                             AK   AWOS

            HIGHEST PEAK WIND RECORDED. WIND GUSTS ABOVE 71 MPH FROM
            934 AM THROUGH 1256 PM.

&&

AHILL