Gale Warning 1, NWS Anchorage, AK

962 
FZAK62 PAFC 011252
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
352 AM AKST Mon Jan 1 2018

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.

PKZ499-020145-
352 AM AKST Mon Jan 1 2018
.SYNOPSIS FOR CENTRAL BERING SEA...

A 975 mb low at 57N 175W remains nearly stationary through tonight, 
weakening to 982 mb. The low then dissipates Tue afternoon. A 960 mb 
low at 50N 161W moves to 58N 159W at 972 mb tonight and then moves 
inland. A front approaches the western Aleutians Tue night.

$$

PKZ411-020145-
Bering Sea Offshore West of 180 and East of the International
Dateline-
352 AM AKST Mon Jan 1 2018

...GALE WARNING TODAY...

.TODAY...N wind 25 to 35 kt. Seas 16 to 23 ft. Freezing spray 
through the morning. Snow showers.
.TONIGHT...NW wind 15 to 30 kt. Seas 12 to 17 ft.
.TUE...NW wind 10 to 20 kt. Seas 8 to 13 ft.
.TUE NIGHT...W wind up to 15 kt. Seas 5 to 9 ft.
.WED THROUGH THU...E wind 15 to 30 kt. Seas 9 to 17 ft.
.FRI...S wind 15 to 30 kt. Seas 12 to 20 ft.

$$

PKZ412-020145-
Bering Sea Offshore 171W to 180 and North of 56N-
352 AM AKST Mon Jan 1 2018

.TODAY...E wind 10 to 25 kt. Seas 9 to 18 ft.
.TONIGHT...E wind 10 to 15 kt. Seas 7 to 12 ft.
.TUE...N wind 10 to 15 kt. Seas 5 to 9 ft.
.TUE NIGHT...NW wind up to 15 kt. Seas 4 to 7 ft.
.WED THROUGH THU...E wind 25 to 40 kt. Seas 6 to 11 ft.
.FRI...SE wind 20 to 30 kt. Seas 12 to 20 ft.

$$

PKZ413-020145-
Bering Sea Offshore 171W to 180 and South of 56N-
352 AM AKST Mon Jan 1 2018

.TODAY...W wind 10 to 25 kt. Seas 8 to 17 ft.
.TONIGHT...W wind 15 to 30 kt. Seas 9 to 14 ft.
.TUE...W wind 10 to 25 kt. Seas 9 to 14 ft.
.TUE NIGHT...W wind 10 to 20 kt. Seas 6 to 11 ft.
.WED THROUGH THU...SE wind 25 to 40 kt. Seas 9 to 17 ft.
.FRI...S wind 20 to 30 kt. Seas 9 to 17 ft.

$$

PKZ414-020145-
Bering Sea Offshore East of 171W-
352 AM AKST Mon Jan 1 2018

.TODAY...NE wind 10 to 25 kt. Seas 5 to 8 ft.
.TONIGHT...NW wind 10 to 25 kt. Seas 5 to 8 ft.
.TUE...W wind 10 to 20 kt. Seas 5 to 9 ft.
.TUE NIGHT...W wind 10 to 20 kt. Seas 5 to 10 ft.
.WED...S wind 20 to 35 kt. Seas 5 to 10 ft.
.THU...SE wind 25 to 40 kt. Seas 6 to 11 ft.
.FRI...S wind 25 to 40 kt. Seas 15 ft.

$$

730 
FZAK62 PAFC 020033
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
333 PM AKST Mon Jan 1 2018

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.

PKZ499-021430-
333 PM AKST Mon Jan 1 2018
.SYNOPSIS FOR CENTRAL BERING SEA...
A 963 mb low at 55N 158W will move to 61N 162W Tue afternoon and 
continue to weaken as it moves northward. A 977 mb low near 57N 176W
will remain nearly stationary and dissipate Tue evening. A front 
will move over the western Aleutians Wed morning.

$$

PKZ411-021430-
Bering Sea Offshore West of 180 and East of the International
Dateline-
333 PM AKST Mon Jan 1 2018

.TONIGHT...NW wind 15 to 30 kt. Seas 12 to 17 ft.
.TUE...NW wind 10 to 20 kt. Seas 8 to 13 ft.
.TUE NIGHT...W wind 10 to 15 kt. Seas 5 to 9 ft.
.WED...SE wind 15 to 30 kt. Seas 4 to 8 ft.
.WED NIGHT...E wind 20 to 35 kt. Seas 8 to 13 ft.
.THU...E wind 20 to 35 kt. Seas 11 to 19 ft.
.FRI THROUGH SAT...SW wind 15 to 30 kt. Seas 12 to 20 ft.

$$

PKZ412-021430-
Bering Sea Offshore 171W to 180 and North of 56N-
333 PM AKST Mon Jan 1 2018

.TONIGHT...E wind 10 to 15 kt. Seas 6 to 11 ft.
.TUE...N wind 10 to 15 kt. Seas 5 to 9 ft.
.TUE NIGHT...NW wind 10 to 15 kt. Seas 6 ft.
.WED...S wind up to 15 kt. Seas 5 ft.
.WED NIGHT...E wind 25 to 40 kt. Seas 6 to 11 ft.
.THU THROUGH FRI...SE wind 25 to 40 kt. Seas 11 to 19 ft.
.SAT...S wind 25 kt. Seas 12 to 15 ft.

$$

PKZ413-021430-
Bering Sea Offshore 171W to 180 and South of 56N-
333 PM AKST Mon Jan 1 2018

.TONIGHT...W wind 15 to 30 kt. Seas 9 to 15 ft.
.TUE...W wind 10 to 25 kt. Seas 8 to 13 ft.
.TUE NIGHT...W wind 10 to 20 kt. Seas 6 to 11 ft.
.WED...SE wind 20 to 35 kt. Seas 5 to 9 ft.
.WED NIGHT...E wind 25 to 40 kt. Seas 9 to 14 ft.
.THU...SE wind 25 to 40 kt. Seas 11 to 17 ft.
.FRI THROUGH SAT...SW wind 20 to 30 kt. Seas 9 to 17 ft.

$$

PKZ414-021430-
Bering Sea Offshore East of 171W-
333 PM AKST Mon Jan 1 2018

.TONIGHT...N wind 10 to 20 kt. Seas 5 to 8 ft.
.TUE...W wind 10 to 20 kt. Seas 4 to 8 ft.
.TUE NIGHT...W wind 10 to 20 kt. Seas 5 to 10 ft.
.WED...SW wind up to 15 kt. Seas 4 to 8 ft.
.WED NIGHT...SE wind 25 to 40 kt. Seas 5 to 10 ft.
.THU THROUGH FRI...S wind 25 to 40 kt. Seas 9 to 14 ft.
.SAT...S wind 15 to 25 kt. Seas 9 to 14 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
511 AM AKST Sun Dec 31 2017

.ANALYSIS AND UPPER LEVELS...

A vertically-stacked low centered south of St. George this morning
remains the main driver for the ongoing active weather across
Southern Alaska this morning. Around the southern periphery of
the low is a zonal Pacific jet advancing eastward. The jet then
turns northward around the east side of the upper low. Thus, much
warmer Pacific air is moving northward through the Gulf of Alaska
and Southcentral, effectively ending the seasonable cold and
returning the area to well above-normal temperatures. Lobes of
energy progressing around the low are spinning off surface lows
that then track into Southern Alaska. The upper level low still
has a good amount of cold air with it, so not every system moving
into Southern Alaska from the south will mean well above-freezing
temperatures. Thus, the location of the rain/snow line will be a
constant forecast problem.

Currently, general east to southeast flow across the area is the
primary factor leading to above freezing temperatures. The winds
are downsloping off each of Southern Alaska's mountain ranges,
causing areas of drying with the warmer conditions. On the
windward (east) side of those same mountains, moderate to heavy
precipitation continues. East-west oriented gaps through the
mountains, including Portage Pass, Turnagain Pass, and the
Kamishak Gap are all expected to pick up strong winds, and with
snow falling in Portage and Turnagain Passes, blizzard conditions
will continue this morning.

&&

.MODEL DISCUSSION...

The models remain in good agreement over the next couple days
tracking a series of lows across the Aleutians, Bering, and Alaska
Peninsula. Despite the good model agreement, the smaller details
of the forecast remain a big challenge. This is especially true of
the location of the rain/snow line, how strong downsloping is to
the lee of the mountains, and the strength of the winds associated
with the lows. Thus, confidence is about average.

&&

.AVIATION...
PANC...VFR conditions and light winds will persist. The ongoing
wind shear will persist into the afternoon, then diminish.

&&

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

A strong low near the eastern AK Pen is moving rapidly north and
will move to the eastern Bering Sea this afternoon. Its associated
weather front is moving north toward the Kenai Peninsula/North
Gulf Coast. The coasts, especially the eastern Kenai Peninsula,
and the upslope portion of the Alaska/Aleutian Ranges will receive
the brunt of the precipitation. Precipitation west of the Chugach
Mountains, mainly snow, will be limited by the strong cross-
barrier flow. Cold air in place will slowly erode along the
coasts, with snow giving way to rain or mix today. Temperatures
may warm enough in some inland areas over the Kenai Peninsula to
shift from snow to a mix this afternoon. The snow over the eastern
Kenai will be heaviest today with the front and will coincide
with the strongest winds. Blizzard conditions still look
reasonable for portions of the eastern Kenai inland/higher
elevations. The precipitation and winds diminish later today as
the front weakens along the coast.

The next in a series of lows/fronts will head toward the eastern
AK Pen and Gulf on Monday and bring another round of warming,
winds, and precipitation. These next systems will actually bring
much warmer air and allow for mixed precipitation types to intrude
further inland. Of special note for the marine community is the
dynamic fetch with this next system. Sea states are expected to
increase to near 35 ft over the southwestern Gulf Monday night.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2...Sun and Mon)...
The pattern will remain quite active into the New Year with
several potent low pressure systems moving up from the N Pacific.
The first low is currently punching through the Aleutian Range
towards Bristol Bay. It is in the mid-970 mb range and should
continue to weaken. It produced widespread blowing snow across the
YK-Delta Saturday. Even though the strong winds will persist this
morning as the front slides through, the blowing snow will be
limited as temperatures are on the rise (above freezing in many
spots). This is making for wetter snow along the YK-Delta
coastline and precipitation is even turning to rain further south.
Showers will start to dissipate behind the front. As this system
drives quickly north today, strong south- southeast winds will
persist. Some of the gusts could even flirt briefly with warning
level (75 mph), especially over higher elevations. We expect these
to be isolated and very short-lived, so a warning is not planned.

Early Mon will represent a relative "lull" between the 2 systems.
Winds will come down, most places will be dry, and temperatures
should be several degrees warmer than they have been the past
several days.

By Mon afternoon, the next storm will start to push into the area
from the south. The first impact will be yet another increase in
east-southeast winds. This will favor the usual gaps through the
Aleutian and Alaska Ranges. At this time, winds are not expected
to be as strong as the current system. Precipitation will hold
together as a solid shield as it pushes into the Bristol Bay area
Mon evening. After that, it will start to fragment becoming more
showery in nature. This system will bring another round of warm
air, so most of the precipitation that does fall will be rain.

&&

.MARINE...
Increasing wind waves and large swell will lead to rapidly
building waves late Mon-Tue southeast of Chirikof Island. A strong
low-pressure system will bring south to southwest winds to the
area. It will also bring heavy swell as the low itself moves from
southwest to northeast. This will allow waves to build from 15-20
feet Mon afternoon to 35-40 ft overnight into Tue. Mariners should
exercise caution in this area.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2...Sun and
Mon)...
The Bering and Aleutians will be dominated by a broad trough and
the lack of any real strong system. The broad trough will be
centered at roughly 180 degrees with cyclonic (counter-clockwise)
flow around it. On the eastern periphery, that is where the
widespread moderate precipitation and warm air will be moving up
from the N Pacific. To the west of the trough axis, expect much
colder air. This means gusty winds and moderate to heavy snow
showers. The most intense showers look to stay over the Aleutian
Chain west of Dutch Harbor on Monday.

&&

.LONG TERM FORECAST (Days 3 through 7)...
The front associated with a 960 mb low crossing the Alaska
Peninsula and moving into Bristol Bay, will lift north from the
Gulf of Alaska over southcentral Alaska Monday evening. Strong
southeasterly flow will bring abundant precipitation to the Gulf
Coastal regions and adjacent mountains particularly along east to
southeast facing slopes with both heavy rain near sea level and
snow higher up and in colder sheltered valleys. Additionally, the
tight pressure gradient will bring strong east to southeast winds
to the typical favorably oriented gaps and valleys as well as
into the Anchorage Bowl late Monday night through Tuesday morning,
while downslope warming increases temperatures in these windy
areas into the upper 30s to low 40s.

The strong southeasterly flow will diminish through the day on
Tuesday as the surface low fills and tracks north towards to the
Kuskokwim Delta coast. An upper level trough rotating around the
south side of this low will spread cold air aloft across the
Alaska Peninsula Tuesday and into Southwest and Southcentral
Alaska Tuesday night and Wednesday. Ridging will begin building
over mainland Alaska Thursday and Friday in response to a deep low
north Pacific low crossing the central Aleutians and tracking
into the Bering. Uncertainty remains high regarding this system
but current model runs are forecasting the minimum depth of the
surface low to be around 940 mb. The associated front will reach
Southwest Alaska Friday night or Saturday then stall as it hits
the large upper level ridge. Cold westerly flow and snow showers
will prevail over the Bering in the broad upper level trough that
forms once the low lifts north, while in southcentral Alaska under
the large ridge, fog and low stratus will be the main forecast
challenge for the end of the week.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Blizzard Warning 125.
MARINE...Gales 119 125 129 132 136 137 139 140 141 150 155 160 165
         180 185 351 352 411 412. Heavy freezing spray 181.

&&

SYNOPSIS AND MODEL DISCUSSION...JW
SOUTHCENTRAL ALASKA...RMC
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MO
LONG TERM...JR