Gale Warning 412, NWS Anchorage, AK

154 
FZAK61 PAFC 152358
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
358 PM AKDT Sun Sep 15 2019

Offshore waters forecast for the Gulf of Alaska West of 144W

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.

PKZ399-161315-
358 PM AKDT Sun Sep 15 2019
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 996 mb low at 59N 150W moves to 56N 143W at 990 mb by Mon 
afternoon as high pressure builds back into the Western Gulf.

$$

PKZ351-161315-
Gulf of Alaska Offshore North of 57N and West of 144W-
358 PM AKDT Sun Sep 15 2019

...GALE WARNING THROUGH MONDAY...

.TONIGHT...S wind 20 to 35 kt in the evening shifting to W. Seas 8 
to 13 ft. Rain.
.MON...N to W wind 20 to 35 kt. Seas 9 to 14 ft.
.MON NIGHT...N wind 15 to 30 kt becoming W up to 20 kt after
midnight. Seas 8 to 13 ft.
.TUE...W wind 10 to 20 kt. Seas 7 ft.
.TUE NIGHT...SW wind 15 to 30 kt. Seas 5 to 9 ft.
.WED THROUGH THU...W wind 15 to 30 kt. Seas 7 to 12 ft.
.FRI...SW wind 15 kt. Seas 4 to 7 ft.

$$

PKZ352-161315-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
358 PM AKDT Sun Sep 15 2019

...GALE WARNING THROUGH MONDAY NIGHT...

.TONIGHT...S wind 25 to 40 kt in the evening shifting to W. Seas 10 
to 15 ft. Rain.
.MON...NW wind 30 to 45 kt. Seas 12 to 19 ft. Rain.
.MON NIGHT...NW wind 25 to 40 kt diminishing to 15 to 25 kt after
midnight. Seas 9 to 17 ft.
.TUE...W wind 10 to 25 kt. Seas 8 ft.
.TUE NIGHT...SW wind 15 to 30 kt. Seas 7 to 11 ft.
.WED THROUGH FRI...SW wind 15 to 30 kt. Seas 7 to 12 ft.

$$

371 
FZAK61 PAFC 161143
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
343 AM AKDT Mon Sep 16 2019

Offshore waters forecast for the Gulf of Alaska West of 144W

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.

PKZ399-170100-
343 AM AKDT Mon Sep 16 2019
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 983 mb low near 58N 145W will exit across the southeastern Gulf 
Mon afternoon through Mon night. A front will enter the enter the 
southwestern Gulf Tue afternoon and track to the northern Gulf 
Tue night.

$$

PKZ351-170100-
Gulf of Alaska Offshore North of 57N and West of 144W-
343 AM AKDT Mon Sep 16 2019

...GALE WARNING TODAY...

.TODAY...N to NW wind 20 to 35 kt. Seas 8 to 13 ft.
.TONIGHT...N to W wind 10 to 25 kt. Seas 7 to 11 ft.
.TUE...W wind 10 to 20 kt. Seas 8 ft.
.TUE NIGHT...SW wind 15 to 30 kt. Seas 6 to 9 ft.
.WED THROUGH THU...SW wind 15 to 30 kt. Seas 8 to 13 ft.
.FRI...S wind 10 to 20 kt. Seas 4 to 8 ft.

$$

PKZ352-170100-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
343 AM AKDT Mon Sep 16 2019

...GALE WARNING TODAY...

.TODAY...NW wind 25 to 35 kt. Seas 11 to 16 ft.
.TONIGHT...NW wind 15 to 30 kt. Seas 9 to 14 ft.
.TUE...W wind 20 kt. Seas 6 to 9 ft.
.TUE NIGHT...SW wind 15 to 30 kt. Seas 7 to 10 ft.
.WED...SW wind 30 kt. Seas 9 to 14 ft.
.THU...SW wind 10 to 25 kt. Seas 9 to 13 ft.
.FRI...SW wind 20 kt. Seas 5 to 8 ft.

$$

908 
FZAK61 PAFC 162355
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
355 PM AKDT Mon Sep 16 2019

Offshore waters forecast for the Gulf of Alaska West of 144W

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.

PKZ399-171345-
355 PM AKDT Mon Sep 16 2019
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...
A 987 mb low over the eastern Gulf will move into the northeastern 
Pacific through Tue afternoon. A front associated with a 987 mb 
Bering Sea low will enter the far southwestern Gulf Tue evening and 
moves into the northeastern Gulf early Wed then remains stationary 
through Wednesday afternoon before diminishing.

$$

PKZ351-171345-
Gulf of Alaska Offshore North of 57N and West of 144W-
355 PM AKDT Mon Sep 16 2019

...GALE WARNING TONIGHT...

.TONIGHT...NW wind 25 to 35 kt becoming W 10 to 25 kt after midnight.
Seas 7 to 13 ft.
.TUE...W wind 10 to 20 kt. Seas 8 ft.
.TUE NIGHT...SW wind 10 to 25 kt becoming S 20 to 30 kt after
midnight. Seas 8 ft. Rain.
.WED...SW wind 30 kt. Seas 8 to 11 ft.
.WED NIGHT...SW wind 20 to 30 kt. Seas 10 to 13 ft.
.THU THROUGH SAT...SW wind 10 to 20 kt. Seas 6 to 11 ft.

$$

PKZ352-171345-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
355 PM AKDT Mon Sep 16 2019

...GALE WARNING TONIGHT...

.TONIGHT...NW wind 25 to 35 kt becoming W 10 to 20 kt after midnight.
Seas 12 to 17 ft.
.TUE...W wind 20 kt. Seas 6 to 9 ft.
.TUE NIGHT...SW wind 15 to 30 kt. Seas 9 ft.
.WED...SW wind 30 kt. Seas 9 to 14 ft.
.WED NIGHT...SW wind 30 kt. Seas 11 to 15 ft.
.THU...SW wind 10 to 25 kt. Seas 9 to 13 ft.
.FRI...SW wind 20 kt. Seas 5 to 8 ft.
.SAT...W wind 25 kt. Seas 9 to 14 ft.

$$

513 
FZAK61 PAFC 171156
OFFAER

Offshore Waters Forecast
National Weather Service Anchorage AK
356 AM AKDT Tue Sep 17 2019

Offshore waters forecast for the Gulf of Alaska West of 144W

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.

PKZ399-180200-
356 AM AKDT Tue Sep 17 2019
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...
Weak high pressure exits the Southeastern Gulf for Wed afternoon. A 
front stretches across the North Gulf Coast and Gulf through Thu 
morning.

$$

PKZ351-180200-
Gulf of Alaska Offshore North of 57N and West of 144W-
356 AM AKDT Tue Sep 17 2019

.TODAY...W wind 10 to 20 kt. Seas 8 ft.
.TONIGHT...SW wind 10 to 25 kt becoming S 20 to 30 kt after
midnight. Seas 7 to 10 ft. Rain.
.WED...SW wind 30 kt. Seas 11 ft.
.WED NIGHT...SW wind 20 to 30 kt. Seas 10 to 13 ft.
.THU THROUGH FRI...S wind 15 to 30 kt. Seas 6 to 11 ft.
.SAT...W wind 20 to 30 kt. Seas 11 to 14 ft.

$$

PKZ352-180200-
Gulf of Alaska Offshore South of 57N North of 55N and West of
144W-
356 AM AKDT Tue Sep 17 2019

.TODAY...W wind 20 kt. Seas 8 ft.
.TONIGHT...SW wind 15 to 30 kt. Seas 9 ft.
.WED...SW wind 30 kt. Seas 10 to 14 ft.
.WED NIGHT...SW wind 30 kt. Seas 11 to 15 ft.
.THU THROUGH FRI...SW wind 10 to 25 kt. Seas 8 to 13 ft.
.SAT...W wind 20 to 30 kt. Seas 12 to 15 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
505 PM AKDT Sat Sep 14 2019

.ANALYSIS AND UPPER LEVELS...
Today is the break in between systems as an upper level ridge
builds over the mainland part of the state. The low that has been
in the Bering Sea for days has now kicked southeast and is now in
the far southeast Gulf of Alaska. The next low is in the Western
Bering Sea and moving eastward rather quickly. The jet stream is
helping to move things along as the 250 mb jet is over 150 kt as
it moves through the Bering Sea, southwest mainland Alaska and
through the Gulf of Alaska.

&&

.MODEL DISCUSSION...
Overall there is good agreement with the models into early next
week. There are some subtle differences in the expected amount of
downsloping on the models. That are impacting the amount of QPF on
the lee side of the mountain ranges, but it does look overall like
the downsloping will be minimal in part due to the amount of
moisture in the system.

&&

.AVIATION...
PANC...VFR conditions and light winds will persist through
tonight. Turnagain Arm winds will be present on Sunday morning
into the afternoon. This could bring some gusty southeast conditions
into the terminal for a few hours, but confidence in the exact
timing is low. Rain will move in to the area around noon on Sunday
and may bring ceilings down to the MVFR level.

&&

.FIRE WEATHER...

Most of Southcentral will see wetting rains with the system moving
in on Sunday. Gusty southeast winds will also develop through the
typical gaps, to include Turnagain and Knik Arms and the Copper
River Valley.

&&

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

Offshore flow and diminishing cloud cover will prevail tonight as
a low in the Gulf exits to the southeast. Sunday will bring a
return to wet weather, as a low in the Bering pushes eastward.
Expect a triple point low to form south of the parent low.
Enhanced southeast gap winds are likely along Turnagain Arm and
the Knik River Valley Sunday morning, then in the Copper River
Valley Sunday afternoon as the east to west pressure gradient
increases. Despite southeast flow at the surface, the upper low
should maintain steady south/southwest winds aloft. Thus,
confidence is high that precipitation will be widespread, and even
areas that are frequently shadowed, including Anchorage and the
eastern Kenai Peninsula, will see up to a half inch of rain
by Sunday night.

The parent low will shift eastward through the Gulf Monday, and
the main area of showers will pull east as well. Shortwaves
rotating around the backside of the low could bring some showers
to the Copper River Basin, but in general a drying trend will be
underway Monday as a ridge begins to build over Southwest AK.

As for marine weather, widespread small craft advisory level
winds and seas are expected in the Gulf Sunday into Monday.
Highest winds and seas will initially be in the western Gulf, then
spread to the eastern Gulf by Sunday evening as the surface low
tracks eastward. In addition, a gale force barrier jet is
expected along the north Gulf coast, east of Prince William
Sound. Areas of gales are likely as early as Sunday night, as
cold northwest flow wraps around the backside of the low and
enhances the pressure gradient.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1-2: Sat-Mon)...

The stacked low pressure system over the central Bering pushes
eastward overnight with the associated front moving inland across
the Southwest this evening. This system slows down as is moves
across land which will result in rain accumulations between one
half to one inch, with locally higher amounts. Light onshore flow
this evening will be variable on Sunday. In the wake of this
system the general flow will be from the north. The next front is
quick to follow with the boundary expected to push to the
Southwest coast early Tuesday morning...spreading inland through
the afternoon. This system will bring another round of appreciable
rainfall...especially for Bristol Bay and the Kuskokwim Valley
late Tuesday into Wednesday as the subtropical jet noses across
from the eastern Bering.

&&

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

An active weather pattern is in store through Tuesday as one
storm system currently over the Bering is followed by the next
system Sunday night. The low currently over the Bering tracks
eastward tonight, passing over Saint Matthew Island by early
Sunday morning. The associated front will bring southerly small
craft winds and widespread rain across the central and eastern
waters through early Sunday morning before tapering off.

The next low pushes a front to the Central and Western Aleutians
Sunday night. Winds and precipitation chances were increased for
much of the the Bering locations as models trend toward better
agreement on the strength and track of this system through
Tuesday. The 997 mb low driving the front crosses over the
Central Aleutians by Monday afternoon and tracks to the Pribilof
Islands at 991 mb Tuesday afternoon.

&&

.MARINE (Days 3 through 5)...
There is high confidence of a low moving through the Central
Bering on Tuesday that will bring gale force winds to the area. As
the low tracks to the east and weakens, winds will diminish for
the Bering and Gulf. There is good confidence that another low
will approach the Aleutians Wednesday into Thursday and that it
will bring small craft winds to the islands.

&&

.LONG TERM FORECAST (Days 3 through 7)...
Models are starting to fall in line with the system tracking
across the Bering Tuesday and there is now good agreement of
widespread rain for southern Alaska Tuesday and Wednesday. On
Wednesday another low approaches the western Aleutians from the
North Pacific with it expected to stay south of the Aleutians
through Thursday while it tracks to the east. Thursday night the
models struggle with what to do with this system, lowering
confidence heading towards the weekend. Because of this the
ensembles were preferred by the end of the week.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Gale Warning 150-160, 172, 177, 352, 132.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...EZ/MSO
SOUTHCENTRAL ALASKA...MM
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...KH
MARINE/LONG TERM...DK