Small Craft Advisory 149, NWS Anchorage, AK

586 
FZAK52 PAFC 161236
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
336 AM AKST Fri Feb 16 2018

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.

PKZ199-170115-
336 AM AKST Fri Feb 16 2018
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...
A front over the western Bering moves to the central Bering
tonight and reaches the eastern Bering Sat night. A complex 1003 
mb low develops 170 nm southeast of Adak tonight and moves 300 nm
north of Adak Sat afternoon at 997 mb and then moves into the 
Gulf of Anadyr Sat night. A front approaches the western Aleutians
Sat night.

$$

PKZ150-170115-
South of the AK Peninsula Sitkinak to Castle Cape-
336 AM AKST Fri Feb 16 2018

...GALE WARNING TODAY...

.TODAY...NW wind 35 kt. Seas 10 ft.
.TONIGHT...NW wind 20 kt. Seas 10 ft.
.SAT...E wind 20 kt becoming SE 30 kt in the afternoon. Seas 8 ft.
.SAT NIGHT...SE wind 35 kt. Seas 17 ft.
.SUN...W wind 30 kt. Seas 15 ft.
.MON THROUGH TUE...SW wind 25 kt. Seas 10 ft.

$$

PKZ155-170115-
South of the AK Peninsula Castle Cape to Cape Sarichef-
336 AM AKST Fri Feb 16 2018

...GALE WARNING SATURDAY...

.TODAY...NW wind 25 kt diminishing to 15 kt in the afternoon. Seas
12 ft.
.TONIGHT...E wind 30 kt. From the Shumagin Islands E, NE wind 15
kt becoming E 25 kt after midnight. Seas 10 ft.
.SAT...E wind 40 kt except SE 35 kt from the Shumagin Islands E.
Seas 20 ft. From the Shumagin Islands E, seas 9 ft building to 14
ft in the afternoon. Rain.
.SAT NIGHT...S wind 35 kt. Seas 19 ft.
.SUN THROUGH MON...S wind 30 kt. Seas 15 ft.
.TUE...SW wind 25 kt. Seas 14 ft.

$$

PKZ160-170115-
Bristol Bay-
336 AM AKST Fri Feb 16 2018

...SMALL CRAFT ADVISORY TODAY AND SATURDAY...

.TODAY...NW wind 30 kt diminishing to 15 kt in the afternoon. Seas
in ice free waters 6 ft.
.TONIGHT...N wind 10 kt becoming E after midnight. Seas in ice
free waters 5 ft.
.SAT...E wind 30 kt. Seas in ice free waters 5 ft. Freezing spray.
.SAT NIGHT...SE wind 35 kt. Seas in ice free waters 8 ft.
.SUN...SW wind 30 kt. Seas in ice free waters 6 ft.
.MON THROUGH TUE...SW wind 25 kt. Seas in ice free waters 7 ft.

$$

PKZ165-170115-
Port Heiden to Cape Sarichef-
336 AM AKST Fri Feb 16 2018

...GALE WARNING SATURDAY...

.TODAY...S wind 20 kt. From Port Moller E, NW wind 20 kt in the
morning becoming variable 10 kt. Seas 11 ft.
.TONIGHT...E wind 25 kt. Seas 8 ft.
.SAT...SE wind 45 kt. From Port Moller E, E wind 30 kt becoming SE
40 kt in the afternoon. Seas 12 ft. Rain.
.SAT NIGHT...S wind 35 kt. Seas 11 ft.
.SUN THROUGH MON...S wind 35 kt. Seas 10 ft.
.TUE...S wind 30 kt. Seas 9 ft.

$$

PKZ170-170115-
Cape Sarichef to Nikolski Bering Side-
336 AM AKST Fri Feb 16 2018

...GALE WARNING TONIGHT AND SATURDAY...

.TODAY...S wind 30 kt. Seas 13 ft.
.TONIGHT...SE wind 35 kt. Seas 10 ft. Rain.
.SAT...SE wind 45 kt. Seas 16 ft. Rain and snow.
.SAT NIGHT...SW wind 25 kt. Seas 11 ft.
.SUN THROUGH MON...S wind 40 kt. Seas 14 ft.
.TUE...S wind 25 kt. Seas 10 ft.

$$

PKZ171-170115-
Unalaska Bay-
336 AM AKST Fri Feb 16 2018

...GALE WARNING SATURDAY...

.TODAY...S wind 20 kt. Seas 3 ft.
.TONIGHT...SE wind 30 kt. Seas 3 ft building to 5 ft after
midnight.
.SAT...SE wind 40 kt becoming S 25 kt in the afternoon. Seas 6 ft.
Rain.
.SAT NIGHT...SW wind 15 kt. Seas 2 ft.
.SUN THROUGH MON...S wind 30 kt. Seas 4 ft.
.TUE...S wind 20 kt. Seas 3 ft.

$$

PKZ172-170115-
Cape Sarichef to Nikolski Pacific Side-
336 AM AKST Fri Feb 16 2018

...GALE WARNING TONIGHT AND SATURDAY...

.TODAY...S wind 15 kt becoming SE 25 kt in the afternoon. Seas
12 ft.
.TONIGHT...E wind 30 kt increasing to 40 kt after midnight. Seas
10 ft building to 20 ft after midnight. Rain.
.SAT...SE wind 45 kt becoming S 35 kt in the afternoon. Seas 24
ft. Rain.
.SAT NIGHT...SW wind 25 kt. Seas 16 ft.
.SUN THROUGH MON...S wind 40 kt. Seas 20 ft.
.TUE...S wind 25 kt. Seas 17 ft.

$$

PKZ173-170115-
Nikloski to Seguam Island Bering Side-
336 AM AKST Fri Feb 16 2018

...GALE WARNING THROUGH TONIGHT...

.TODAY...S wind 40 kt. Seas 14 ft.
.TONIGHT...SE wind 35 kt. Seas 13 ft. Snow.
.SAT...SE wind 20 kt becoming SW in the afternoon. Seas 11 ft.
.SAT NIGHT...SW wind 20 kt. Seas 10 ft.
.SUN THROUGH MON...S wind 40 kt. Seas 20 ft.
.TUE...S wind 20 kt. Seas 12 ft.

$$

PKZ174-170115-
Nikolski to Seguam Island Pacific Side-
336 AM AKST Fri Feb 16 2018

...GALE WARNING TODAY...

.TODAY...SE wind 35 kt. Seas 15 ft.
.TONIGHT...SE wind 30 kt. Seas 18 ft. Snow.
.SAT...S wind 20 kt. Seas 19 ft.
.SAT NIGHT...SW wind 25 kt. Seas 17 ft.
.SUN...S wind 45 kt. Seas 23 ft.
.MON...S wind 40 kt. Seas 23 ft.
.TUE...S wind 25 kt. Seas 18 ft.

$$

PKZ175-170115-
Seguam Island to Adak Bering Side-
336 AM AKST Fri Feb 16 2018

...GALE WARNING THROUGH TONIGHT...

.TODAY...S wind 45 kt. Seas 19 ft.
.TONIGHT...S wind 35 kt becoming SE 25 kt after midnight. Seas
15 ft. Snow and rain.
.SAT...S wind 15 kt. Seas 9 ft.
.SAT NIGHT...SW wind 20 kt. Seas 9 ft.
.SUN...S wind 40 kt. Seas 16 ft.
.MON...SW wind 40 kt. Seas 14 ft.
.TUE...S wind 15 kt. Seas 9 ft.

$$

PKZ176-170115-
Seguam Island to Adak Pacific Side-
336 AM AKST Fri Feb 16 2018

...GALE WARNING THROUGH TONIGHT...

.TODAY...S wind 45 kt. Seas 26 ft.
.TONIGHT...S wind 35 kt becoming SE 25 kt after midnight. Seas
24 ft.
.SAT...Variable wind 10 kt becoming SW 20 kt in the afternoon.
Seas 18 ft.
.SAT NIGHT...SW wind 25 kt. Seas 16 ft.
.SUN...S wind 40 kt. Seas 23 ft.
.MON...S wind 35 kt. Seas 23 ft.
.TUE...S wind 20 kt. Seas 18 ft.

$$

PKZ177-170115-
Adak to Kiska-
336 AM AKST Fri Feb 16 2018

...STORM WARNING TODAY...

.TODAY...S wind 50 kt diminishing to 40 kt in the afternoon. Seas
23 ft Bering side...28 ft Pacific side. Rain.
.TONIGHT...S wind 25 kt. Seas 18 ft Bering side...26 ft Pacific 
side. Rain.
.SAT...SW wind 20 kt. Seas 17 ft.
.SAT NIGHT...SW wind 25 kt. Seas 13 ft.
.SUN...S wind 40 kt. Seas 22 ft.
.MON...W wind 40 kt. Seas 22 ft.
.TUE...W wind 15 kt. Seas 12 ft.

$$

PKZ178-170115-
Kiska to Attu-
336 AM AKST Fri Feb 16 2018

...GALE WARNING THROUGH TONIGHT...

.TODAY...S wind 40 kt. Seas 30 ft.
.TONIGHT...S wind 40 kt. Seas 27 ft.
.SAT...W wind 30 kt diminishing to 20 kt in the afternoon. Seas
18 ft.
.SAT NIGHT...S wind 20 kt. Seas 12 ft.
.SUN...SE wind 40 kt. Seas 19 ft.
.MON...W wind 40 kt. Seas 19 ft.
.TUE...SW wind 20 kt. Seas 13 ft.

$$

PKZ179-170115-
Pribilof Islands Near Shore Waters-
336 AM AKST Fri Feb 16 2018

...GALE WARNING THROUGH SATURDAY...

.TODAY...S wind 40 kt. Seas 17 ft.
.TONIGHT...S wind 35 kt becoming SE 25 kt after midnight. Seas
17 ft.
.SAT...SE wind 40 kt. Seas 17 ft. Snow with rain.
.SAT NIGHT...SW wind 20 kt. Seas 16 ft.
.SUN THROUGH MON...S wind 35 kt. Seas 18 ft.
.TUE...SW wind 15 kt. Seas 13 ft.

$$

PKZ180-170115-
Kuskokwim Delta and Etolin Strait-
336 AM AKST Fri Feb 16 2018

...GALE WARNING SATURDAY...

.TODAY...SW wind 20 kt becoming S 30 kt in the afternoon. Seas 9
ft. Patchy freezing fog.
.TONIGHT...S wind 30 kt. Seas 8 ft.
.SAT...E wind 30 kt becoming SE 40 kt in the afternoon. Seas 13
ft.
.SAT NIGHT...SE wind 40 kt. Seas 14 ft.
.SUN THROUGH MON...S wind 30 kt. Seas 10 ft.
.TUE...SW wind 25 kt. Seas 9 ft.

$$

PKZ181-170115-
North and West of Nunivak Island-
336 AM AKST Fri Feb 16 2018

...GALE WARNING SATURDAY...

.TODAY...S wind 30 kt. Seas in ice free waters 9 ft. Patchy
freezing fog.
.TONIGHT...S wind 30 kt. Seas in ice free waters 10 ft. Freezing
spray.
.SAT...SE wind 25 kt becoming E 40 kt in the afternoon. Seas in
ice free waters 12 ft.
.SAT NIGHT...SE wind 40 kt. Seas in ice free waters 13 ft.
.SUN THROUGH MON...S wind 35 kt. Seas in ice free waters 9 ft.
.TUE...SW wind 20 kt. Seas in ice free waters 8 ft.

$$

PKZ185-170115-
Saint Matthew Island Waters-
336 AM AKST Fri Feb 16 2018

...GALE WARNING THROUGH SATURDAY...

.TODAY...S wind 40 kt. Seas 20 ft. Widespread snow showers and
rain.
.TONIGHT...S wind 40 kt diminishing to 30 kt after midnight. Seas
21 ft.
.SAT...E of Saint Matthew Island, SE wind 25 kt increasing to 40
kt in the afternoon. W of Saint Matthew Island, SE wind 30 kt. Seas 
20 ft. Snow.
.SAT NIGHT...S wind 35 kt. Seas 17 ft.
.SUN...S wind 40 kt. Seas 16 ft.
.MON...S wind 40 kt. Seas 25 ft.
.TUE...SW wind 25 kt. Seas 22 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
435 AM AKST Thu Feb 15 2018

.ANALYSIS AND UPPER LEVELS...
An upper level trough over eastern mainland Alaska continues to
push off to the east towards the ALCAN border this morning. Snow
has tapered off over Southcentral while light snow continues over
the Copper River Basin. An upper level ridge is building in
behind the departing trough leading to clearing skies with
widespread areas of fog developing over southwest Alaska and more
recently over the Cook Inlet and the Kenai Peninsula. Further
west, an upper level trough is digging NE across the Western
Aleutians with an associated surface low and frontal system
sweeping across the Central Bering towards the southwest mainland,
bringing gale force winds and rain to the area.

&&

.MODEL DISCUSSION...
Models have come into decent agreement with the evolution and
progression of the longwave pattern over the next couple of days,
with high pressure building in over the central and eastern
portions of the mainland and a more progressive and stormy
pattern out west. Recent model runs have steered away from a more
northward storm track as systems move from the Bering into the
Gulf, which would deflect storms to the south keeping
southcentral in a high and dry pattern heading into next week.

&&

.AVIATION...
PANC...Snow has tapered off overnight as the longwave trough
pushes east, though a rapidly building ridge behind it will trap
low level moisture leading to IFR/LIFR Cigs and the likely
development of fog by 15Z. With fog already developing over Kenai,
conditions are obviously ripe for widespread development over the
Cook Inlet area and into the Anchorage bowl. The densest fog may
take some time to develop this morning as left over low stratus
will slow cooling at the surface, but the building ridge combined
with recent precipitation will eventually take over and should
lead to widespread fog development this morning before lifting in
the afternoon.

&&

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

An upper trough and associated surface front will clear the Copper
River Basin this afternoon. Snow and snow showers will likely
continue with these features as it pushes east. Low stratus and
fog will likely hang around upper Cook Inlet, Anchorage Bowl, and
MAT-SU Valleys this morning with improvement this afternoon. Areas
of stratus and fog could redevelop again tonight across the
Anchorage Bowl and perhaps as far as Palmer in the Mat Valley as
light winds and upper ridging strengthen surface inversions.
Brisk/strong outflow winds will develop over the eastern Kenai
Peninsula/Western Prince William Sound and the North Gulf Coast
this morning and should peak this afternoon before weakening
overnight.

A surface front spreads rain to the western Gulf tonight. The
north progression of the front should stall Friday as a strong
triple point low develops and pulls the front southeast. So
precipitation, mostly snow, will likely only make it as far north
as the Kenai Peninsula before the surface low carries it
southeast. Pressure gradients will once again build along the
Gulf coast and give rise to another round of outflow winds Friday
night.

 &&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
Some areas of lingering cloudy conditions and fog will persist
through this morning, as the residual moisture from the previous
system remains over some areas which cleared out overnight prior
to fog developing. Our focus quickly shifts to an approaching
front pushing into the southwest Mainland starting this afternoon.
This system will weaken as it progresses eastward through Friday,
bringing widespread precipitation to much of the area and mainly
in the form of snow. However, frontal speed will temporally limit
any snowfall accumulation potential, with just light amounts
expected. By Friday evening a weak area of high pressure will
build in over the mainland, and bring another round of clearing
skies and drier conditions through Saturday morning.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
A 979mb low will continue to track northward through the central
Bering through tonight bringing widespread gusty winds and
precipitation to much of the Bering and Aleutians through this
evening. The associated front currently stretching from the
Pribilof Islands through the eastern Aleutians will continue to
spread gusty winds and precipitation over the eastern Bering/
Aleutians and Alaska Peninsula into Friday morning. Right on its
heels is another gale force system working its way into the
western Aleutians by this afternoon, and spreading strong gusty
winds and precipitation eastward into the central Bering/Aleutians
overnight tonight into Friday morning.

&&

.LONG TERM FORECAST (Days 3 through 7)...
As a decaying front across the Anchorage area slides East on
Friday afternoon, only a slight decrease to temperatures and
increase of clouds are to be expected. Temperatures aloft will
cool through that time but begin to rebound into the weekend and
beyond. Skies are expected to clear out by the early weekend. Now
that we are back into the season of the sun helping to aid in
warmth, daytime temperatures will quickly rise. Diurnal swings of
20 degrees, or more, are not out of the question. Interior and
river valley areas of the Copper River Basin should see night
temperatures drop well below zero as any warmth radiates out
overnight. Clouds will increase Sunday afternoon with an
approaching front from the West. However, guidance has a harder
time figuring out how far the front will move to the east. If it
has enough oomph to overtake the ridging over the area, we may see
snow Monday afternoon into the evening hours. The GFS is showing
the strongest of these signals. The EC is indicating a much weaker
front with light snow, and the Canadian is showing nothing.
Regardless, the nature of ridging and troughing will continue
progressively through this weekend and into next.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Heavy Freezing Spray Warning 181.
         Storm Warning 175-177 413.
 Gale Warning 165 170 173 174 178-181 185 352 411 412 414.&&

SYNOPSIS AND MODEL DISCUSSION...KVP
SOUTHCENTRAL ALASKA...RC
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...TP
LONG TERM...SS

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
1016 AM AKST THU FEB 15 2018

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

1012 AM     SNOW             5 ESE WASILLA           61.56N 149.32W
02/15/2018  M2.5 INCH                           AK   CO-OP OBSERVER

1012 AM     SNOW             SUTTON                  61.72N 148.88W
02/15/2018  M2.0 INCH                           AK   TRAINED SPOTTER

            SNOW BEGAN AT 345 PM. DURATION WAS 6+ HRS.

&&

LF

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
152 PM AKST THU FEB 15 2018

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

0151 PM     SNOW             POTTER VALLEY           61.05N 149.79W
02/15/2018  M2.3 INCH        ANCHORAGE          AK   PUBLIC

&&

KH