Gale Warning 579, NWS Anchorage, AK

845 
FZAK62 PAFC 201217
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
317 AM AKST Mon Nov 20 2017

Offshore Waters Forecast for the Bering Sea

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.

PKZ499-210145-
317 AM AKST Mon Nov 20 2017
.SYNOPSIS FOR CENTRAL BERING SEA...
A front over the western Bering sea will track to the eastern 
Bering Sea and then dissipate as it moves onshore Mon night. A 1000 
mb low Tue night at 48N 168E will move to 57N 180E at 990 mb by Wed 
morning.

$$

PKZ411-210145-
Bering Sea Offshore West of 180 and East of the International
Dateline-
317 AM AKST Mon Nov 20 2017

...GALE WARNING THROUGH TONIGHT...

.TODAY...SW wind 35 kt. Seas 14 to 17 ft. Rain.
.TONIGHT...W wind 25 to 40 kt becoming SW 15 to 30 kt after
midnight. Seas 11 to 19 ft.
.TUE...SW wind 15 to 30 kt becoming S in the afternoon. Seas 11 to 
17 ft.
.TUE NIGHT...SE wind 20 to 35 kt. Seas 8 to 13 ft.
.WED...NW wind 25 to 40 kt. Seas 9 to 16 ft.
.THU...SW wind 20 to 30 kt. Seas 10 to 15 ft.
.FRI...S wind 20 to 30 kt. Seas 9 to 15 ft.

$$

PKZ412-210145-
Bering Sea Offshore 171W to 180 and North of 56N-
317 AM AKST Mon Nov 20 2017

...GALE WARNING THROUGH TONIGHT...

.TODAY...S wind 20 to 35 kt. Seas 9 to 17 ft. Rain.
.TONIGHT...W wind 20 to 35 kt. Seas 11 to 19 ft.
.TUE...SW wind 20 to 30 kt. Seas 13 to 20 ft.
.TUE NIGHT...S wind 25 to 40 kt. Seas 11 to 15 ft.
.WED THROUGH THU...W wind 30 to 45 kt. Seas 15 to 23 ft.
.FRI...SW wind 20 to 30 kt. Seas 10 to 13 ft.

$$

PKZ413-210145-
Bering Sea Offshore 171W to 180 and South of 56N-
317 AM AKST Mon Nov 20 2017

.TODAY...SW wind 15 to 30 kt. Seas 8 to 13 ft.
.TONIGHT...NW wind 15 to 30 kt. Seas 9 to 14 ft.
.TUE...SW wind 10 to 20 kt. Seas 8 to 12 ft.
.TUE NIGHT...S wind 30 to 45 kt. Seas 9 to 15 ft.
.WED THROUGH THU...W wind 30 to 45 kt. Seas 15 to 23 ft.
.FRI...S wind 15 to 30 kt. Seas 8 to 12 ft.

$$

PKZ414-210145-
Bering Sea Offshore East of 171W-
317 AM AKST Mon Nov 20 2017

.TODAY...N wind 15 to 30 kt becoming SE 10 to 25 kt in the
afternoon. Seas 9 to 14 ft.
.TONIGHT...W wind 15 to 30 kt. Seas 7 to 12 ft. Rain.
.TUE...NW wind 20 to 30 kt diminishing to 10 to 25 kt in the
afternoon. Seas 9 to 14 ft.
.TUE NIGHT...SW wind 15 to 30 kt. Seas 9 to 13 ft.
.WED...SW wind 30 to 45 kt. Seas 14 to 22 ft.
.THU...NW wind 30 to 45 kt. Seas 17 to 31 ft.
.FRI...W wind 15 to 30 kt. Seas 9 to 14 ft.

$$

683 
FZAK62 PAFC 210034
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
334 PM AKST Mon Nov 20 2017

Offshore Waters Forecast for the Bering Sea

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.

PKZ499-211430-
334 PM AKST Mon Nov 20 2017
.SYNOPSIS FOR CENTRAL BERING SEA...

A 983 mb Gulf of Anadyr low extends a front over the Bering and 
moves into Western Alaska Tue morning. The low slips into the 
Russian Arctic through Wed afternoon. The trailing front links 
with a 1006 mb North Pacific low that moves over St Matthew Island
with its associated front by Wed afternoon.

$$

PKZ411-211430-
Bering Sea Offshore West of 180 and East of the International
Dateline-
334 PM AKST Mon Nov 20 2017

...GALE WARNING TONIGHT AND TUESDAY NIGHT...

.TONIGHT...W wind 25 to 40 kt becoming SW 15 to 30 kt after
midnight. Seas 11 to 19 ft.
.TUE...SW wind 15 to 30 kt becoming S in the afternoon. Seas 9 to
16 ft.
.TUE NIGHT...SE wind 20 to 35 kt. Seas 9 to 14 ft. Rain.
.WED...NW wind 30 to 45 kt. Seas 13 to 21 ft.
.WED NIGHT...W wind 30 to 45 kt. Seas 14 to 22 ft.
.THU...SW wind 20 to 30 kt. Seas 10 to 17 ft.
.FRI...S wind 20 to 30 kt. Seas 9 to 15 ft.
.SAT...W wind 10 to 25 kt. Seas 9 to 14 ft.

$$

PKZ412-211430-
Bering Sea Offshore 171W to 180 and North of 56N-
334 PM AKST Mon Nov 20 2017

...GALE WARNING TONIGHT AND TUESDAY NIGHT...

.TONIGHT...W wind 20 to 35 kt. Seas 11 to 19 ft.
.TUE...SW wind 20 to 30 kt. Seas 13 to 19 ft.
.TUE NIGHT...SW wind 15 to 25 kt becoming SE 25 to 40 kt after
midnight. Seas 11 to 16 ft. Rain.
.WED...W wind 35 to 50 kt. Seas 15 to 23 ft.
.WED NIGHT...NW wind 35 to 50 kt. Seas 24 to 34 ft.
.THU...W wind 35 to 50 kt. Seas 16 to 31 ft.
.FRI THROUGH SAT...W wind 20 to 30 kt. Seas 10 to 13 ft.

$$

PKZ413-211430-
Bering Sea Offshore 171W to 180 and South of 56N-
334 PM AKST Mon Nov 20 2017

...GALE WARNING TUESDAY NIGHT...

.TONIGHT...NW wind 15 to 30 kt. Seas 9 to 13 ft.
.TUE...SW wind 10 to 20 kt. Seas 8 to 12 ft.
.TUE NIGHT...S wind 20 to 35 kt increasing to 30 to 45 kt after
midnight. Seas 9 to 14 ft. Rain showers.
.WED...W wind 30 to 45 kt. Seas 14 to 22 ft.
.WED NIGHT...NW wind 35 to 50 kt. Seas 19 to 32 ft.
.THU...W wind 30 to 45 kt. Seas 14 to 29 ft.
.FRI...S wind 15 to 30 kt. Seas 8 to 12 ft.
.SAT...W wind 10 to 25 kt. Seas 8 to 13 ft.

$$

PKZ414-211430-
Bering Sea Offshore East of 171W-
334 PM AKST Mon Nov 20 2017

.TONIGHT...W wind 15 to 30 kt. Seas 6 to 11 ft. Rain.
.TUE...NW wind 20 to 30 kt diminishing to 10 to 25 kt in the
afternoon. Seas 10 to 14 ft.
.TUE NIGHT...W wind up to 20 kt becoming S 15 to 30 kt after
midnight. Seas 9 to 12 ft.
.WED...S wind 30 to 45 kt. Seas 10 to 18 ft.
.WED NIGHT...W wind 40 to 55 kt. Seas 17 to 32 ft.
.THU...NW wind 40 to 55 kt. Seas 19 to 34 ft.
.FRI...W wind 15 to 30 kt. Seas 9 to 14 ft.
.SAT...SW wind 10 to 25 kt. Seas 7 to 12 ft.

$$

202 
FZAK62 PAFC 211213
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
313 AM AKST Tue Nov 21 2017

Offshore Waters Forecast for the Bering Sea

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.

PKZ499-220200-
313 AM AKST Tue Nov 21 2017
.SYNOPSIS FOR CENTRAL BERING SEA...
A 1003 mb low at 45N 159E will move to 58N 178E at 977 mb by Wed
morning. The low will continue to deepen rapidly to 964 mb as it 
tracks to 61N 168W by Wed evening. The low then moves to 60N 163W at
968 mb through Thu morning.

$$

PKZ411-220200-
Bering Sea Offshore West of 180 and East of the International
Dateline-
313 AM AKST Tue Nov 21 2017

...STORM WARNING WEDNESDAY...

.TODAY...SW wind 15 to 30 kt becoming S in the afternoon. 
Seas 10 to 16 ft.
.TONIGHT...S wind 20 to 35 kt. Seas 10 to 16 ft. Rain showers.
.WED...NW wind 35 to 50 kt. Seas 15 to 23 ft.
.WED NIGHT...W wind 30 to 45 kt. Seas 15 to 23 ft.
.THU THROUGH FRI...S wind 20 to 35 kt. Seas 10 to 18 ft.
.SAT...W wind 15 to 30 kt. Seas 11 to 18 ft.

$$

PKZ412-220200-
Bering Sea Offshore 171W to 180 and North of 56N-
313 AM AKST Tue Nov 21 2017

...STORM WARNING WEDNESDAY...

.TODAY...SW wind 20 to 30 kt. Seas 13 to 20 ft.
.TONIGHT...S wind 15 to 30 kt increasing to 25 to 40 kt after
midnight. Seas 11 to 17 ft. Rain showers and snow showers.
.WED...W wind 35 to 50 kt. Seas 16 to 24 ft building to 23 to 
30 ft in the afternoon. Rain.
.WED NIGHT...NW wind 40 to 55 kt. Seas 24 to 36 ft.
.THU...W wind 35 to 50 kt. Seas 15 to 30 ft.
.FRI THROUGH SAT...W wind 20 to 35 kt. Seas 12 to 20 ft.

$$

PKZ413-220200-
Bering Sea Offshore 171W to 180 and South of 56N-
313 AM AKST Tue Nov 21 2017

...GALE WARNING TONIGHT AND WEDNESDAY...

.TODAY...SW wind 10 to 20 kt. Seas 9 to 13 ft.
.TONIGHT...S wind 30 to 45 kt. Seas 9 to 12 ft building to 11 to
18 ft after midnight. Rain.
.WED...W wind 35 to 45 kt. Seas 16 to 24 ft.
.WED NIGHT...NW wind 35 to 50 kt. Seas 20 to 33 ft.
.THU...W wind 30 to 45 kt. Seas 14 to 29 ft.
.FRI...S wind 20 to 35 kt. Seas 9 to 12 ft.
.SAT...W wind 15 to 30 kt. Seas 9 to 17 ft.

$$

PKZ414-220200-
Bering Sea Offshore East of 171W-
313 AM AKST Tue Nov 21 2017

...GALE WARNING TONIGHT AND WEDNESDAY...

.TODAY...NW wind 20 to 30 kt becoming W 10 to 25 kt in the
afternoon. Seas 10 to 15 ft.
.TONIGHT...SW wind up to 20 kt becoming S 20 to 35 kt after
midnight. Seas 10 to 13 ft. Rain showers.
.WED...SW wind 30 to 45 kt. Seas 9 to 17 ft building to 15 to 23
ft in the afternoon. Rain and snow.
.WED NIGHT...W wind 45 to 60 kt. Seas 20 to 35 ft.
.THU...NW wind 45 to 60 kt. Seas 18 to 33 ft.
.FRI...W wind 15 to 30 kt. Seas 9 to 14 ft.
.SAT...SW wind 15 to 30 kt. Seas 8 to 13 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
432 AM AKST Sun Nov 19 2017

.ANALYSIS AND UPPER LEVELS...

A powerful digging upper level low centered just west of Norton
Sound and its associated influence on the jet is driving all of
the active weather across Southern Alaska this morning. The
primary jet streak lies to the west of the center of the upper
low, which is further enhancing the negative (northwest to
southeast) tilt of the primary shortwave trough axis. As a result,
a strong low, also taking advantage of excellent baroclinicity is
tracking into Southwest Alaska. By now the cold front has largely
swept across all of Southwest Alaska, and all remaining liquid
precipitation is changing back over to snow. The leading edge of
the precipitation is crossing the Alaska Range now (a feat in and
of itself), and will be overspreading Southcentral over the next
few hours. Much of the heaviest snowfall is ongoing across
Southwest Alaska on the west side of the Alaska Range and the
Kuskokwim Mountains. Meanwhile for the Bering, a transition to
much colder temperatures along with very windy conditions is
occurring.

&&

.MODEL DISCUSSION...

The models remain in excellent agreement through the short-term.
All generally agreeing on the synoptic evolution of the ongoing
winter storm and the timing on the next front that will cross the
Bering and move into Southwest Alaska on Tuesday. Thus, the main
model difference once again reside in the local effects, for which
the high-resolution models like the NAMnest were preferred.
Forecast confidence remains high on the broad pattern and somewhat
lower on the local details.

&&

.AVIATION...
PANC...Snow has begun and will intensify through the morning
bringing visibilities to MVFR to occasional IFR with any stronger
bands. The snow will taper to snow showers late morning and end
completely during the afternoon, resulting in improving conditions
back to VFR through Monday morning.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3)...

Southcentral Mainland...
A weakening occluded front is spreading snow across much of
Southcentral today. Snow should diminish during the afternoon
inland and the evening to overnight hours along the coasts. The
Kenai Peninsula will get a fair amount of snow today with the
western Kenai Peninsula expected to hit advisory levels (4 to 8
inches). Gusty winds developing later today will also reduce
visibilities in blowing snow. Elsewhere across Southcentral snow
amounts should not exceed 2 to 4 inches. Outflow and Gap
conditions are expected to develop across the north Gulf and the
Matanuska Valley beginning overnight. The strongest outflow
conditions will be along the north Gulf coast.

Kodiak and the Gulf waters...
A developing triple-point low near Kodiak will move slowly east
today and then track south Monday. This center will produce
widespread gales and storms over the northern and western Gulf
waters. These conditions will hold through tonight before slowly
diminishing and pushing south Monday afternoon. Snow mixed at
times will rain along with strong winds and blowing snow potential
are expected to continue over Kodiak through tonight. A slight
change in the positions of the triple could make a big difference
in snowfall potential. Stay tuned for updates.

&&

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

Early this morning, a strong cold front is stretched from just
east of Aniak to King Salmon at 4 AM. Ahead of this front,
widespread snow has developed, some of which has been heavy with
visibilities reduced to one quarter of a mile. Behind the front,
the precipitation becomes more showery in nature with mainly snow
showers observed in the Kuskokwim Delta south towards Bristol Bay,
before things change over to liquid form. However, strong
northwest winds (currently pushing 55 mph) have already pushed
inland along the coast from Goodnews Bay north and this will
continue to spread southeast through the remainder of the morning,
changing all precipitation back to snow showers. Additional
accumulations of up to 2 inches remain possible for the Bethel
area and points towards the coast, with less towards King Salmon.
Further inland along the Kuskokwim mountains and Alaska Range,
another 3 to 6 inches looks like a good bet before the storm
giving us the snow exits the region as it heads towards the Gulf
of Alaska. Although the winds will gradually diminish over the
next 36 hours, blowing snow will continue to be a concern through
that time.

&&

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

Winds will continue to increase in strength today for the eastern
half of the Bering Sea and AKPEN. A strong area of low pressure
will continue its trek from Nome towards the eastern Kodiak
Island vicinity. A vigorous 125kt mid level jet already stretches
across the region. However, the leading edge of 850 mb cold
advection and drying aloft is lagging a few hundred miles behind
the surface front. This will continue to dive southeast heading
through the morning and into the afternoon. As this occurs,
vertical mixing will rapidly increase with hurricane force gusts
likely for the region. Western areas of the Alaska Peninsula and
Eastern Bering see will see the longest duration of such winds
compared to points further west. With that in mind, the current
headlines look good and only minor tweaks to the forecast were
made.

Further west, a ridge of high pressure stretched across the
western Aleutians and this ridge will shift eastward through this
evening before de-amplifying overnight. Heading into Monday, A
strong low moving across eastern Siberia will send yet another
cold front eastward across the Bering Sea Monday into Tuesday,
with strong winds developing across the northern half of the
region.

Another low will move into the western Bering by Wednesday
morning, with an attendant warm front sweeping northeast.
Widespread precipitation will develop along this feature and we
were tempted to add in a mention of fog but decided to hold off
for another forecast cycle or two, as some models differ on the
strength of the warm air aloft moving into the area. This low
will rapidly deepen as it heads towards the Kuskokwim Delta by
late Wednesday evening, deepening 26 mb as it does so. As such,
you guessed it, more strong winds are likely, possibly reaching
storm force.

&&

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

After Tuesday's system moves out of Alaska, a shortwave ridge will
once again move in over most of the state. This will bring a
period of clear skies and seasonably cold to below normal
temperatures in some valleys through Wednesday evening. Yet
another system will approach Alaska from the west beginning
Wednesday night, traversing the Bering Sea on a very similar path
to the previous two systems. This will bring a repeat of strong
westerly winds followed by strong northwesterly winds for the
Bering Coast and the AK Pen. Precipitation type looks like it will
be less of a challenge with this system, as it has colder air
aloft than the current systems. Current thinking is that it will
remain all snow for the West Coast on Thursday, but that may
change as the system gets closer.

This system is currently expected to bottom out at 970 mb as it
approaches the West Coast. As it crosses the AK Pen, it develops a
secondary low in the Gulf of Alaska which should help to draw
some colder air down from the Interior. As a result, outflow winds
are expected to pick up on the southern side of the AK Pen and in
the usual channeled areas throughout Southcentral. If the system
remains as strong as forecast, the weather challenge for the end
of next week will be strong northerly winds for both east and
west.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...High Wind Warning: 181 185 195.
Winter Weather Advisory: 121 152 161 171.

MARINE...
Storm Warning: 119 120 131 132 136 137 155 165 170-172 179-181
185 352 412 414.
Gale Warning: 127 130 138 139 150 160 173 174 178 351 411 413.

&&

SYNOPSIS AND MODEL DISCUSSION...JPW
SOUTHCENTRAL ALASKA...RMC
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...PD
LONG TERM...LF

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
921 AM AKST SUN NOV 19 2017

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

0800 AM     FREEZING RAIN    BETHEL                  60.77N 161.77W
11/19/2017  M0.20 INCH                          AK   OFFICIAL NWS OBS

            STORM TOTAL ICE ACCUMULATION - WSO BETHEL

&&

RA