Gale Warning 127, NWS Anchorage, AK

697 
FZAK62 PAFC 261250
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
350 AM AKST Mon Feb 26 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.

PKZ499-270245-
350 AM AKST Mon Feb 26 2018
.SYNOPSIS FOR CENTRAL BERING SEA...

A 1004 mb low at 51N 171E moves inland near 58N 158W at 999 mb by
Tue morning. A 954 mb low at 47N 169E Tue morning moves to 54N 168E 
at 950 mb by Wed morning.

$$

PKZ411-270245-
Bering Sea Offshore West of 180 and East of the International
Dateline-
350 AM AKST Mon Feb 26 2018

...GALE WARNING TUESDAY...

.TODAY...Variable wind 15 kt. Seas 8 to 13 ft.
.TONIGHT...W wind 10 to 20 kt. Seas 7 to 12 ft.
.TUE...S wind 10 to 25 kt becoming SE 30 to 45 kt in the
afternoon. Seas 7 to 12 ft.
.TUE NIGHT...SE wind 30 to 45 kt. Seas 13 to 21 ft.
.WED...S wind 35 to 50 kt. Seas 18 to 32 ft.
.THU...SW wind 20 to 35 kt. Seas 16 to 24 ft.
.FRI...S wind 30 to 45 kt. Seas 9 to 17 ft.

$$

PKZ412-270245-
Bering Sea Offshore 171W to 180 and North of 56N-
350 AM AKST Mon Feb 26 2018

.TODAY...W wind 10 to 25 kt. Seas 12 to 20 ft.
.TONIGHT...W wind 15 to 30 kt. Seas 8 to 11 ft.
.TUE...W wind 15 to 30 kt becoming SW up to 20 kt in the
afternoon. Seas 8 to 11 ft. Freezing spray N of 58N in the morning.
.TUE NIGHT...SE wind 25 to 40 kt. Seas 9 to 14 ft.
.WED THROUGH THU...SW wind 25 to 40 kt. Seas 13 to 21 ft.
.FRI...SW wind 20 to 35 kt. Seas 9 to 13 ft.

$$

PKZ413-270245-
Bering Sea Offshore 171W to 180 and South of 56N-
350 AM AKST Mon Feb 26 2018

.TODAY...SW wind 15 to 30 kt. Seas 13 to 21 ft. Snow and rain.
.TONIGHT...W wind 15 to 30 kt becoming NW 10 to 20 kt after 
midnight. Seas 10 to 14 ft.
.TUE...NE wind up to 15 kt becoming SE 15 to 30 kt in the
afternoon. Seas 9 ft.
.TUE NIGHT...SE wind 25 to 40 kt. Seas 9 to 14 ft.
.WED THROUGH FRI...SW wind 25 to 40 kt. Seas 10 to 18 ft.

$$

PKZ414-270245-
Bering Sea Offshore East of 171W-
350 AM AKST Mon Feb 26 2018

...STORM WARNING TODAY...

.TODAY...W wind 35 to 50 kt diminishing to 15 to 30 kt in the
afternoon. Seas 20 to 33 ft subsiding to 14 to 22 ft in the
afternoon. Snow.
.TONIGHT...W wind 15 to 30 kt. Seas 9 to 15 ft.
.TUE...NW wind 15 to 30 kt. Seas 9 to 12 ft.
.TUE NIGHT...SW wind 10 to 25 kt. Seas 7 to 10 ft.
.WED...SE wind 20 to 35 kt. Seas 8 to 13 ft.
.THU...SW wind 20 to 35 kt. Seas 8 to 13 ft.
.FRI...W wind up to 15 kt. Seas 6 to 10 ft.

$$

947 
FZAK62 PAFC 270023
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
323 PM AKST Mon Feb 26 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.

PKZ499-271415-
323 PM AKST Mon Feb 26 2018
.SYNOPSIS FOR CENTRAL BERING SEA...

A North Pacific low moves to 52N 168E at 949 mb Tue night and 
continues to 57N 169E at 954 mb Wed afternoon. Its front pushes 
across the Western Aleutians by Wed afternoon. High pressure 
moves into Western Alaska through Wed afternoon.

$$

PKZ411-271415-
Bering Sea Offshore West of 180 and East of the International
Dateline-
323 PM AKST Mon Feb 26 2018

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

.TONIGHT...SW wind 10 to 25 kt. Seas 7 to 12 ft.
.TUE...SE wind 10 to 25 kt increasing to 30 to 45 kt in the
afternoon. Seas 8 to 13 ft. Snow.
.TUE NIGHT...SE wind 30 to 45 kt. Seas 10 to 18 ft building to 16
to 24 ft after midnight. Rain and snow.
.WED...S wind 35 to 50 kt. Seas 18 to 32 ft.
.WED NIGHT...SW wind 30 to 45 kt. Seas 20 to 32 ft.
.THU...SW wind 20 to 35 kt. Seas 16 to 24 ft.
.FRI...S wind 30 to 45 kt. Seas 9 to 17 ft.
.SAT...SW wind 25 to 40 kt. Seas 17 to 22 ft.

$$

PKZ412-271415-
Bering Sea Offshore 171W to 180 and North of 56N-
323 PM AKST Mon Feb 26 2018

...GALE WARNING TUESDAY NIGHT...

.TONIGHT...W wind 15 to 30 kt. Seas 8 to 11 ft.
.TUE...W wind 15 to 30 kt becoming variable up to 20 kt in the 
afternoon. Seas 8 to 12 ft.
.TUE NIGHT...SE wind 25 to 40 kt. Seas 8 to 16 ft. Snow and rain.
.WED...S wind 25 to 40 kt. Seas 12 to 20 ft.
.WED NIGHT...S wind 15 to 30 kt. Seas 14 to 22 ft.
.THU...SW wind 15 to 30 kt. Seas 13 to 21 ft.
.FRI THROUGH SAT...SW wind 20 to 35 kt. Seas 9 to 17 ft.

$$

PKZ413-271415-
Bering Sea Offshore 171W to 180 and South of 56N-
323 PM AKST Mon Feb 26 2018

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

.TONIGHT...W wind 15 to 30 kt becoming NW up to 20 kt after
midnight. Seas 10 to 15 ft. Snow.
.TUE...SE wind up to 15 kt increasing to 20 to 35 kt in the
afternoon. Seas 7 to 10 ft.
.TUE NIGHT...SE wind 25 to 40 kt. Seas 9 to 17 ft. Rain.
.WED...S wind 25 to 40 kt. Seas 14 to 19 ft.
.WED NIGHT...SW wind 15 to 30 kt. Seas 11 to 19 ft.
.THU THROUGH SAT...SW wind 25 to 40 kt. Seas 9 to 17 ft.

$$

PKZ414-271415-
Bering Sea Offshore East of 171W-
323 PM AKST Mon Feb 26 2018

.TONIGHT...W wind 15 to 30 kt. Seas 10 to 15 ft. Snow.
.TUE...W wind 15 to 30 kt. Seas 9 to 12 ft.
.TUE NIGHT...W wind up to 20 kt becoming SE 15 to 30 kt after
midnight. Seas 7 to 10 ft.
.WED...SE wind 20 to 35 kt. Seas 7 to 12 ft.
.WED NIGHT...SE wind 20 to 35 kt. Seas 9 to 14 ft.
.THU...SW wind 20 to 35 kt. Seas 8 to 13 ft.
.FRI...W wind up to 15 kt. Seas 6 to 10 ft.
.SAT...SW wind 10 to 25 kt. Seas 6 to 11 ft.

$$

661 
FZAK62 PAFC 271235
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
335 AM AKST Tue Feb 27 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.

PKZ499-280300-
335 AM AKST Tue Feb 27 2018
.SYNOPSIS FOR CENTRAL BERING SEA...

A front over the western Aleutians will move over the eastern 
Aleutians through Thu morning. The associated North Pacific low 
will move to 53N 167E at 947 mb Wed morning then exit the western 
Bering Thu morning. 

$$

PKZ411-280300-
Bering Sea Offshore West of 180 and East of the International
Dateline-
335 AM AKST Tue Feb 27 2018

...STORM WARNING WEDNESDAY...

.TODAY...S wind 10 to 25 kt becoming SE 30 to 45 kt in the
afternoon. Seas 8 to 13 ft. Snow.
.TONIGHT...SE wind 30 to 45 kt. Seas 10 to 18 ft building to 17 to
20 ft after midnight. Rain and snow.
.WED...S wind 35 to 50 kt. Seas 18 to 32 ft.
.WED NIGHT...S wind 30 to 45 kt. Seas 22 to 34 ft.
.THU...SW wind 20 to 35 kt. Seas 16 to 24 ft.
.FRI...S wind 30 to 45 kt. Seas 9 to 17 ft.
.SAT...SW wind 25 to 40 kt. Seas 17 to 22 ft.

$$

PKZ412-280300-
Bering Sea Offshore 171W to 180 and North of 56N-
335 AM AKST Tue Feb 27 2018

...GALE WARNING TONIGHT AND WEDNESDAY...

.TODAY...W wind 15 to 30 kt becoming SW 10 to 20 kt in the 
afternoon. Seas 8 to 12 ft. Freezing spray N of 58N in the morning.
.TONIGHT...SE wind 30 to 45 kt. Seas 9 ft building to 9 to 16 ft
after midnight. Rain.
.WED...S wind 25 to 40 kt. Seas 13 to 21 ft. Rain and snow.
.WED NIGHT...S wind 15 to 30 kt. Seas 14 to 22 ft.
.THU...SW wind 15 to 30 kt. Seas 15 to 23 ft.
.FRI THROUGH SAT...SW wind 20 to 35 kt. Seas 9 to 17 ft.

$$

PKZ413-280300-
Bering Sea Offshore 171W to 180 and South of 56N-
335 AM AKST Tue Feb 27 2018

...GALE WARNING TONIGHT AND WEDNESDAY...

.TODAY...Variable wind 15 kt becoming SE 15 to 30 kt in the 
afternoon. Seas 9 ft.
.TONIGHT...SE wind 25 to 40 kt. Seas 9 to 17 ft. Rain.
.WED...S wind 25 to 40 kt. Seas 13 to 18 ft. Rain.
.WED NIGHT...SW wind 15 to 30 kt. Seas 12 to 20 ft.
.THU THROUGH SAT...SW wind 25 to 40 kt. Seas 10 to 18 ft.

$$

PKZ414-280300-
Bering Sea Offshore East of 171W-
335 AM AKST Tue Feb 27 2018

...GALE WARNING WEDNESDAY...

.TODAY...NW wind 15 to 30 kt. Seas 9 to 13 ft.
.TONIGHT...W wind up to 20 kt becoming SE 15 to 30 kt after
midnight. Seas 8 ft.
.WED...SE wind 20 to 35 kt. Seas 7 to 12 ft.
.WED NIGHT...SE wind 20 to 35 kt. Seas 9 to 14 ft.
.THU...SW wind 15 to 30 kt. Seas 8 to 13 ft.
.FRI...W wind up to 15 kt. Seas 7 to 12 ft.
.SAT...SW wind 10 to 25 kt. Seas 6 to 11 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
514 AM AKST Sun Feb 25 2018

.ANALYSIS AND UPPER LEVELS...
Skies are in the process of clearing out across much of
Southcentral Alaska this morning as dry northwest flow and weak
cold air advection are established behind a departing trough over
the panhandle. Patchy fog has formed over Upper Cook Inlet and
into the Copper River Basin as a result of the clearing skies and
falling temperatures. The northwest flow pattern is also supporting
widespread gale force winds across the western Gulf including
Kodiak Island. A transient upper level ridge is moving over the
southwest mainland, promoting widespread stratus development with
some areas of fog across Bristol Bay supported by onshore flow at
the surface. Meanwhile, the next trough poised to impact the
mainland is moving into the western Bering Sea. A strong warm
front extends across the central and eastern Bering from a surface
low north of Attu, bringing widespread rain and southeast winds
to the Pribilofs and Eastern Aleutians as well as the Alaska
Peninsula. A wide swath of storm force winds is moving into the
western Bering aided by strong cold advection on the back side of
the low.

&&

.MODEL DISCUSSION...
Models continue to show good synoptic agreement in the short term
as a progressive pattern remains in place over the region through
the early part of next week. The current weak outflow pattern
over Southcentral will quickly be replaced by the Bering system as
it occludes and then tracks eastward across the mainland Sunday
night into Monday, bringing another round of snow to much of the
region. This then looks to be followed by another round of outflow
winds by Tuesday as that system departs to the east.

&&

.AVIATION...
PANC...Patchy fog over the Upper Cook Inlet region will keep the
potential for IFR/LIFR conditions at the terminal through the
morning hours, with VFR conditions and light winds expected for
the rest of the day once the fog lifts. Snow will then spread into
the terminal beginning around 08z tonight, bringing a return of
IFR conditions to coincide with the most intense snowfall through
early Monday morning. Conditions may improve to MVFR towards the
end of the TAF period as snow begins to diminish in intensity.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
Outflow winds along the North Gulf Coast and some patchy fog
around Northern Cook Inlet will be the primary forecast concerns
today as a ridge of high pressure slides over the South Mainland.
The most significant winds will continue to blow from the Barren
Islands southward into Kodiak Island, however a brief uptick in
the outflow winds in Seward, Whittier, and Valdez will continue
until late this morning. As far as the fog/stratus around Cook
Inlet, there is enough mixing from the offshore flow to prevent it
from becoming too widespread, however a few patchy areas will
continue drifting around the area until late this morning.

The focus then shifts to the incoming front that will bring a
quick shot of snow to Kodiak Island this evening, and then spread
northward into the Gulf Coast and Southcentral for late tonight
into Monday. With no downsloping and temperatures remaining well
cold enough to support snow for the entire event, confidence has
increased enough in the potential significant accumulations in
Anchorage and the Matanuska Valley for Winter Weather Advisories
to be issued this morning. The biggest concern from this event
will with the heaviest snowfall that is expected to fall during
the Monday morning commute, with additional snowfall that should
persist into the afternoon commute. The Matanuska Valley and
Hatcher Pass will likely see the highest accumulations from this
event due to its southwest-west flow that tends to allow snowfall
to linger longer than other areas. This event will also likely
not have the distinct back edge than the last 2 recent snow events
had due to broad cyclonic westerly flow that will persist into
Tuesday. As a result scattered snow shower activity will likely
linger through Monday night, though most of the accumulating
snowfall should end in most areas of Southcentral by early Monday
evening.

&&

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

A short lived period of quiet weather will grace Southwest Alaska
this morning before the next system comes charging across the
Bering Sea towards the western coast. A frontal system will make
landfall this afternoon bringing another round of snow to most
locations, with 2-4" accumulating by the end of the day on Monday.
Over a foot of snow is expected for upslope locations on the
western side of the Kuskokwim and Alaska Ranges as strong westerly
flow will help promote good orographic lifting. Farther south
over the AKPEN, a nose of warmer air will push up with the system
Sunday afternoon leading to precipitation falling mostly as rain
over the southern AKPEN while rain will mix with snow further
north towards King Salmon before changing over to all snow in the
evening.

Colder air moves in behind the front causing temperatures to fall
through the day on Monday, with high temps expected in the
early morning. The cold air advection will also lead to strong
west/northwesterly winds Sunday night into Monday across Bristol
Bay and into the lower Kuskokwim River Valley. Winds could gust
as high as 50-60 mph along the Bristol Bay coast with even higher
gusts possible through channeled terrain over the AKPEN. Because
of the strong northwest flow, snow showers will continue in the
mountains through much of the day, potentially continuing through
much of Monday night.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2: Sunday
and Monday)...
An upper level trough will reassert itself over the Bering Sea
today replacing a transient upper level ridge, continuing the
progressive pattern seen across the area this week. A strong
surface low will move west across the central Bering today with an
associated frontal system sweeping across the Bering and
Aleutians bringing rain which will change to snow showers on the
backside of the front. A 140 kt jet max on the bottom of the upper
level trough will support the development of this system bringing
a swath of storm force surface winds (50 kt) and building seas to
the Bering Sea between the Aleutians and Pribilofs Sunday
afternoon through Monday morning. The long fetch of the westerly
winds will build seas to over 35 ft by Sunday night.

Once the low moves into Southwest Alaska, conditions will calm
down somewhat, with a much weaker low moving into the western
Aleutians late Sunday night into Monday morning. This weak low
will slowly track eastward through the central Bering through
Monday night, but no hazardous weather is expected from it.

&&

.LONG TERM FORECAST (Days 3 through 7)...
The progressive pattern with zonal westerly flow will continue
Monday night into Tuesday with a couple more cold troughs tracking
across southern Alaska. West to northwesterly outflow will
increase across Southcentral Alaska and the western Gulf Monday
night following the passage of one trough. The next trough,
bringing additional cold air aloft with it, will swing into
Southwest Alaska Monday night and continue into Southcentral and
the Gulf Tuesday with another small shortwave following through
the northwesterly flow aloft late Tuesday night through Wednesday
morning.

Further out to the west, a rapidly deepening north Pacific low
will track north towards the western Aleutians on Tuesday and
then cross into the western Bering Tuesday night and Wednesday.
With the low still strengthening as it passes not far to the west
of Shemya, storm force or stronger winds are likely. In response
to the deepening storm, a strong upper level ridge will build over
the central Bering Tuesday and then continue to amplify as it
shifts east over the eastern Bering Tuesday Night and west coast
of Alaska Wednesday.

Forecast confidence decreases rapidly Friday through the weekend
due to uncertainty in how fast the large ridge will push east and
in what manner it will break down. Models, however, do agree on
general trend back towards active zonal flow for the first half of
next week.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Weather Advisory 101, 111.
MARINE...Storm 132, 138, 165, 170, 175, 177, 178, 179, 352, 411, 413, 414.
Gale 119, 120, 130, 131, 136, 137, 139, 141, 150, 155, 160, 171, 172, 173,
     174, 176, 180, 185, 351, 412.
Heavy Freezing Spray 130, 181, 185.

&&

SYNOPSIS AND MODEL DISCUSSION...CB
SOUTHCENTRAL ALASKA...DEK
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...KVP
LONG TERM...JR