Gale Warning 284, NWS Anchorage, AK

Issued

Mar 20, 2020, 3:01 PM AKDT (23:01 UTC)

Expired

Mar 21, 2020, 3:45 AM AKDT

In force

13 hr

Issued by

NWS Anchorage, AK

239 
FZAK52 PAFC 202301
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
301 PM AKDT Fri Mar 20 2020

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.

PKZ199-211145-
301 PM AKDT Fri Mar 20 2020
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A front moves into Southwest Alaska tonight. A large, 
strengthening area of high pressure over the western and central 
Aleutians builds into the eastern Bering through Sat through Sun.

$$

PKZ150-211145-
South of the AK Peninsula Sitkinak to Castle Cape-
301 PM AKDT Fri Mar 20 2020

...GALE WARNING SATURDAY AND SATURDAY NIGHT...

.TONIGHT...S wind 15 kt increasing to 25 kt after midnight. Seas 7 
ft. Rain.
.SAT...SW wind 25 kt becoming NW 35 kt in the afternoon. Seas 10
ft.
.SAT NIGHT...NW wind 35 kt. Seas 11 ft.
.SUN...NW wind 30 kt. Seas 10 ft.
.SUN NIGHT...NW wind 25 kt. Seas 8 ft.
.MON THROUGH TUE...SW wind 20 kt. Seas 6 ft.
.WED...NW wind 20 kt. Seas 8 ft.

$$

PKZ155-211145-
South of the AK Peninsula Castle Cape to Cape Sarichef-
301 PM AKDT Fri Mar 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY NIGHT...

.TONIGHT...SW wind 25 kt. Seas 8 ft. Rain.
.SAT...W wind 20 kt except NW 30 kt from E of the Shumagin Islands. Seas
8 ft.
.SAT NIGHT...N wind 25 kt. Seas 9 ft.
.SUN...N wind 15 kt. Seas 8 ft.
.SUN NIGHT...Variable wind 10 kt. Seas 6 ft.
.MON THROUGH TUE...SW wind 20 kt. Seas 8 ft.
.WED...W wind 20 kt. Seas 8 ft.

$$

PKZ160-211145-
Bristol Bay-
301 PM AKDT Fri Mar 20 2020

...SMALL CRAFT ADVISORY SATURDAY AND SATURDAY NIGHT...

.TONIGHT...S wind 15 kt. Seas in ice free waters 2 ft. Snow and 
rain.
.SAT...NW wind 30 kt. Seas in ice free waters 4 ft.
.SAT NIGHT...NW wind 25 kt diminishing to 15 kt after midnight. Seas
in ice free waters 3 ft.
.SUN...NW wind 15 kt. Seas in ice free waters 1 foot.
.SUN NIGHT...W wind 10 kt. Seas in ice free waters 1 foot.
.MON...SE wind 10 kt. Seas in ice free waters 1 foot.
.TUE...SW wind 10 kt. Seas in ice free waters 1 foot.
.WED...W wind 15 kt. Seas in ice free waters 2 ft.

$$

PKZ165-211145-
Port Heiden to Cape Sarichef-
301 PM AKDT Fri Mar 20 2020

...SMALL CRAFT ADVISORY SATURDAY AND SATURDAY NIGHT...

.TONIGHT...S wind 20 kt. Seas 7 ft. Rain.
.SAT...NW wind 25 kt. Seas 7 ft.
.SAT NIGHT...NW wind 25 kt diminishing to 15 kt after midnight. Seas
7 ft.
.SUN...N wind 15 kt. Seas 4 ft.
.SUN NIGHT...E wind 15 kt. Seas 3 ft.
.MON...SE wind 20 kt. Seas 4 ft.
.TUE...S wind 20 kt. Seas 4 ft.
.WED...W wind 15 kt. Seas 5 ft.

$$

PKZ170-211145-
Cape Sarichef to Nikolski Bering Side-
301 PM AKDT Fri Mar 20 2020

.TONIGHT...SW wind 15 kt becoming NW after midnight. Seas 7 ft.
.SAT...NW wind 20 kt. Seas 7 ft.
.SAT NIGHT...NE wind 20 kt. Seas 6 ft.
.SUN...E wind 20 kt. Seas 5 ft.
.SUN NIGHT...SE wind 25 kt. Seas 5 ft.
.MON...SE wind 30 kt. Seas 7 ft.
.TUE...S wind 20 kt. Seas 6 ft.
.WED...W wind 15 kt. Seas 5 ft.

$$

PKZ171-211145-
Unalaska Bay-
301 PM AKDT Fri Mar 20 2020

.TONIGHT...S wind 10 kt becoming NW after midnight. Seas 2 ft
building to 5 ft after midnight. Rain.
.SAT...N wind 20 kt. Seas 5 ft.
.SAT NIGHT...NE wind 15 kt. Seas 5 ft.
.SUN...E wind 15 kt. Seas 2 ft.
.SUN NIGHT...SE wind 20 kt. Seas 3 ft.
.MON...SE wind 25 kt. Seas 4 ft.
.TUE...S wind 15 kt. Seas 2 ft.
.WED...W wind 10 kt. Seas 2 ft.

$$

PKZ172-211145-
Cape Sarichef to Nikolski Pacific Side-
301 PM AKDT Fri Mar 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY NIGHT...

.TONIGHT...S wind 15 kt becoming NW after midnight. Seas 8 ft. Rain.
.SAT...N wind 20 kt. Seas 9 ft.
.SAT NIGHT...NE wind 25 kt, except 15 kt E of Seguam Island. Seas 10
ft.
.SUN AND SUN NIGHT...E wind 25 kt. Seas 10 ft.
.MON...SE wind 30 kt. Seas 12 ft.
.TUE...S wind 20 kt. Seas 10 ft.
.WED...W wind 20 kt. Seas 8 ft.

$$

PKZ173-211145-
Nikolski to Seguam Island Bering Side-
301 PM AKDT Fri Mar 20 2020

.TONIGHT...NW wind 15 kt. Seas 7 ft.
.SAT...NW wind 15 kt. Seas 7 ft.
.SAT NIGHT...E wind 20 kt. Seas 7 ft.
.SUN AND SUN NIGHT...E wind 30 kt. Seas 11 ft.
.MON...SE wind 30 kt. Seas 12 ft.
.TUE...SW wind 20 kt. Seas 8 ft.
.WED...SW wind 15 kt. Seas 6 ft.

$$

PKZ174-211145-
Nikolski to Seguam Island Pacific Side-
301 PM AKDT Fri Mar 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY NIGHT...

.TONIGHT...N wind increasing to 20 kt. Seas 8 ft.
.SAT...NE wind 20 kt. Seas 10 ft.
.SAT NIGHT...E wind increasing to 30 kt. Seas 11 ft.
.SUN AND SUN NIGHT...E wind 30 kt. Seas 14 ft.
.MON...SE wind 30 kt. Seas 13 ft.
.TUE...SW wind 20 kt. Seas 12 ft.
.WED...SW wind 15 kt. Seas 8 ft.

$$

PKZ175-211145-
Seguam Island to Adak Bering Side-
301 PM AKDT Fri Mar 20 2020

.TONIGHT...NW wind 10 kt. Seas 6 ft.
.SAT...Variable wind 10 kt. Seas 5 ft.
.SAT NIGHT...E wind increasing to 20 kt. Seas 6 ft.
.SUN AND SUN NIGHT...E wind 30 kt. Seas 10 ft.
.MON...SE wind 25 kt. Seas 10 ft.
.TUE THROUGH WED...S wind 15 kt. Seas 5 ft.

$$

PKZ176-211145-
Seguam Island to Adak Pacific Side-
301 PM AKDT Fri Mar 20 2020

...SMALL CRAFT ADVISORY SATURDAY AND SATURDAY NIGHT...

.TONIGHT...N wind 15 kt. Seas 7 ft.
.SAT...NE wind 20 kt. Seas 9 ft.
.SAT NIGHT...E wind increasing to 30 kt. Seas 11 ft.
.SUN AND SUN NIGHT...E wind 30 kt. Seas 15 ft.
.MON...SE wind 25 kt. Seas 13 ft.
.TUE...SW wind 20 kt. Seas 11 ft.
.WED...S wind 15 kt. Seas 6 ft.

$$

PKZ177-211145-
Adak to Kiska-
301 PM AKDT Fri Mar 20 2020

...SMALL CRAFT ADVISORY SATURDAY NIGHT...

.TONIGHT...Variable wind 10 kt. Seas 7 ft.
.SAT...SE wind 15 kt. Seas 7 ft.
.SAT NIGHT...E wind increasing to 25 kt. Seas 9 ft.
.SUN AND SUN NIGHT...E wind 30 kt. Seas 14 ft.
.MON...SE wind 20 kt. Seas 12 ft.
.TUE...S wind 15 kt. Seas 8 ft.
.WED...SE wind 20 kt. Seas 7 ft.

$$

PKZ178-211145-
Kiska to Attu-
301 PM AKDT Fri Mar 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY NIGHT...

.TONIGHT...S wind increasing to 30 kt. Seas 8 ft.
.SAT...S wind 30 kt. Seas 12 ft.
.SAT NIGHT...S wind 30 kt. Seas 12 ft.
.SUN AND SUN NIGHT...E wind 20 kt. Seas 10 ft.
.MON...NE wind 15 kt. Seas 10 ft.
.TUE THROUGH WED...SE wind 20 kt. Seas 9 ft.

$$

PKZ179-211145-
Pribilof Islands Near Shore Waters-
301 PM AKDT Fri Mar 20 2020

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TONIGHT...W wind increasing to 20 kt. Seas 9 ft.
.SAT...NW wind 20 kt in the morning becoming variable 10 kt. Seas
8 ft.
.SAT NIGHT...Variable wind 10 kt. Seas 6 ft.
.SUN...S wind 15 kt. Seas 4 ft.
.SUN NIGHT...SE wind 20 kt. Seas 6 ft.
.MON...SE wind 20 kt. Seas 6 ft.
.TUE...S wind 15 kt. Seas 5 ft.
.WED...Variable wind 10 kt. Seas 4 ft.

$$

PKZ180-211145-
Kuskokwim Delta and Etolin Strait-
301 PM AKDT Fri Mar 20 2020

...SMALL CRAFT ADVISORY SATURDAY...

.TONIGHT...S wind 20 kt. Seas in ice free waters 2 ft.
.SAT...NW wind 25 kt. Seas in ice free waters 3 ft. Freezing
spray.
.SAT NIGHT...NW wind 20 kt. Seas in ice free waters 3 ft.
.SUN AND SUN NIGHT...W wind 15 kt. Seas in ice free waters 1 foot.
.MON...SE wind 20 kt. Seas in ice free waters 2 ft.
.TUE...SW wind 20 kt. Seas in ice free waters 2 ft.
.WED...W wind 15 kt. Seas in ice free waters 1 foot.

$$

PKZ181-211145-
North and West of Nunivak Island-
301 PM AKDT Fri Mar 20 2020

...BRISK WIND ADVISORY TONIGHT...

.TONIGHT...S wind 25 kt becoming W 15 kt after midnight.
.SAT...W wind 20 kt.
.SAT NIGHT...Variable wind 10 kt becoming S 20 kt after midnight.
.SUN...SW wind 25 kt.
.SUN NIGHT...SW wind 20 kt.
.MON...S wind 20 kt.
.TUE THROUGH WED...W wind 15 kt.

$$

PKZ185-211145-
Saint Matthew Island Waters-
301 PM AKDT Fri Mar 20 2020

...HEAVY FREEZING SPRAY WARNING TONIGHT...
...SMALL CRAFT ADVISORY THROUGH SATURDAY NIGHT...

.TONIGHT...W wind 20 kt. Seas in ice free waters 10 ft. Heavy
freezing spray.
.SAT...E of Saint Matthew Island, NW wind 15 kt. W of Saint
Matthew Island, W wind 15 kt becoming SW 25 kt in the afternoon. 
Seas in ice free waters 6 ft.
.SAT NIGHT...E of Saint Matthew Island, SW wind 15 kt becoming S
25 kt after midnight. W of Saint Matthew Island, S wind 25 kt.
Seas in ice free waters 9 ft.
.SUN...SW wind 25 kt. Seas in ice free waters 11 ft.
.SUN NIGHT...S wind 20 kt. Seas in ice free waters 10 ft.
.MON...S wind 20 kt. Seas in ice free waters 8 ft.
.TUE...W wind 15 kt. Seas in ice free waters 6 ft.
.WED...SW wind 15 kt. Seas in ice free waters 6 ft.

$$

NWS Anchorage, AK wrote its last area forecast discussion before this gale warning went out at Mar 20, 4:52 AM AKDT, 10 hours 9 minutes earlier.

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
452 AM AKDT Fri Mar 20 2020

.ANALYSIS AND UPPER LEVELS...

An upper level shortwave trough is exiting the Copper River Basin
to the east this morning. A flat ridge with embedded 115 kt jet
streak extends over the Kuskokwim Valley. A much stronger
shortwave trough is moving over the western Bering. The fast
progressive flow associated with that jet streak is keeping the
weather highly changeable from day to day.

Much of Southcentral and Southwest are under mostly cloudy skies.
Clearing is mostly prevalent over the Kenai Peninsula and western
Susitna Valley. Fog and low stratus are prevalent over much of
Bristol Bay and the Susitna Valley. Remnant low stratus persists
over portions of the Copper River Basin and Prince William Sound
as a result of yesterday's frontal passage. Temperatures are
hovering at to a couple degrees above freezing in many areas with
south to southwesterly winds helping keep temperatures up this
morning.

&&

.MODEL DISCUSSION...

Model agreement remains very good through late Saturday night, as
a large area of high pressure south of the Alaska Peninsula, a
front tracking over the northern Bering and into mainland Alaska,
and a new high building in over the Bering are the primary players
in the forecast. Many areas are starting out the day at their
warmest levels, so temperatures are going to be a challenge today,
especially as they relate to the movement, formation, or
dissipation of the low stratus that has enveloped much of the
area. Nevertheless, overall forecast confidence is high.

&&

.AVIATION...
PANC...VFR conditions and light winds will persist today through
tonight. The next round of snow will begin Saturday morning, and
will persist through much of the afternoon. MVFR conditions are
expected early in the morning, but IFR conditions are likely for
much of the day. Winds will remain light during Saturday's snow.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
The upper level wave that brought rain and snow to the Cook Inlet
region yesterday is in the eastern Copper River Basin as of early
this morning and will be well into the Yukon Territory by late
morning. This will bring in zonal flow aloft over Southcentral
Alaska today. This translates into fair skies and a break in the
precipitation before the next system arrives tomorrow.

For Saturday, a moist airmass will move into the region from the
southwest as a cold upper level trough digs into the area from
the northwest. Flow aloft will be southwesterly and temperatures
aloft will be cold enough to support snow for most of the region.
However, precipitation-type will be the biggest challenge for
tomorrow. It looks as if Kenai and northward (including the Copper
River Basin) will see snow. Temperatures will be in the mid 30s
across much of the area and that will mitigate the snow
accumulation. Homer should warm enough to make 40 degrees, but
temperatures aloft will be cold enough for snow and dewpoints look
to remain in the upper 20s.

This system will also move through rather quickly leaving Sunday
as a clear and dry day with the potential for gusty northerly
winds to develop through the typical areas of channeled terrain.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
(Today through Saturday evening)

The main feature of interest will be an approaching shortwave
trough from the west. Warmer air and increasing moisture just
above the surface will precede this feature, with perhaps a weak
area of surface low pressure developing near Bristol Bay ahead of
these features. The net effect will be with the increased ascent
(lift) associated with the incoming trough, and the theta
advection (amount of warm air and moisture moving into a region),
widespread precipitation development is anticipated by Friday
night while continuing into your Saturday. Most of this will be in
the form of snow, but a few areas closer to the coast may see a
brief mix or change over to rain as you get an added heat flux of
the ocean. As for snowfall, accumulations will be light, with most
areas likely seeing 2 to 4 inches of accumulation.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
(Today through Saturday evening)

A shortwave trough crossing the central Bering today will allow
for showery type precipitation to develop here. Further south, an
approaching disturbance in the southwesterly flow ahead of the
trough will cross the eastern Aleutians by this evening.
Increasing amounts of lift (ascent), warmth, and moisture (both
just above the surface) will interact to foster an increased
coverage and intensity of rain and snow, especially for eastern
portions of the Bering, the eastern Aleutians, and the Alaska
Peninsula (AKPEN). Mixed precipitation is possible for all of
these areas, with a higher likelihood that rain will be the more
predominant type as you get closer to the AKPEN and Aleutian
chain.

Further west, high pressure will build across the region behind
the departing trough, with decreasing cloud cover and dry
conditions expected.

&&

.MARINE (Days 3 through 5)...
A ridge of high pressure in place of the eastern Bering will keep
things generally quiet through the early part of next week. A
weakening North Pacific low moves northward over the central
Aleutians Sunday on Monday. This will create some elevated
southeasterly winds through gaps and passes along the central and
eastern Aleutians through Monday. As this system weakens
significantly and the high moves eastward, generally quiet
conditions area expected across the Bering for Tuesday.

Meanwhile for the Gulf, a building high over the eastern Bering
and a departing low centered over the southeastern Gulf will
generate elevated winds through Sunday in usual gaps and passes,
including Kamishak Bay and the Barren Islands. Winds will
diminish throughout the day on Monday as high pressure moves in,
leading to generally quiet conditions over the Gulf for Tuesday.

&&

.LONG TERM FORECAST (Days 3 through 7)...
There is moderate confidence that a strong upper level ridge will
be in place over the southern half of the state early next week.
A series of progressive upper level shortwaves will eventually
force the ridge to weaken and move southward by midweek, opening
up a zonal flow pattern aloft. By the end of the week, models
suggest a strong low will approach from the Bering from the west,
through there is little confidence in track at this time. Due to
uncertainty with models in the long term, we have low to moderate
confidence in the forecast. With them continuing to depict a ridge
to start next week, we are gaining confidence in that feature.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Heavy Freezing Spray Warning: 185.

&&

SYNOPSIS AND MODEL DISCUSSION...JPW
SOUTHCENTRAL ALASKA...EZ
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...PD
MARINE/LONG TERM...KO

Gale Warnings in Alaska, 2020Every gale warning in 2020

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text.