Gale Warning 400, NWS Anchorage, AK

734 
FZAK52 PAFC 012255
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
255 PM AKDT Fri Jun 1 2018

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.

PKZ199-021130-
255 PM AKDT Fri Jun 1 2018
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 972 MB low 150 NM west southwest of Shemya will intensify to 
965 MB 100 NM north of Shemya Friday night then weaken to 981 MB 
360 NM north of Shemya Sunday afternoon. A low will move off the 
southern Kamchatka Peninsula Saturday night and be a 987 mb low 60
NM north of Shemya Sunday afternoon. 

$$

PKZ150-021130-
South of the AK Peninsula Sitkinak to Castle Cape-
255 PM AKDT Fri Jun 1 2018

.TONIGHT...W wind 10 kt. Seas 5 ft.
.SAT...W wind 15 kt. Seas 4 ft.
.SAT NIGHT...SW wind 15 kt. Seas 5 ft.
.SUN AND SUN NIGHT...SE wind 15 kt. Seas 7 ft.
.MON...SE wind 20 kt. Seas 7 ft.
.TUE THROUGH WED...SE wind 15 kt. Seas 7 ft.

$$

PKZ155-021130-
South of the AK Peninsula Castle Cape to Cape Sarichef-
255 PM AKDT Fri Jun 1 2018

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

.TONIGHT...W wind 10 kt. Seas 5 ft.
.SAT...S wind increasing to 30 kt except S 20 kt from the Shumagin 
Islands E. Seas 8 ft. Rain.
.SAT NIGHT...S wind 25 kt becoming SW 15 kt by midnight. Seas 9 ft. 
Rain.
.SUN...Variable wind 10 kt. Seas 8 ft.
.SUN NIGHT...Variable wind 10 kt. Seas 8 ft.
.MON...S wind 20 kt. Seas 10 ft.
.TUE THROUGH WED...SW wind 15 kt. Seas 8 ft.

$$

PKZ160-021130-
Bristol Bay-
255 PM AKDT Fri Jun 1 2018

.TONIGHT...W wind 15 kt. Seas 3 ft.
.SAT...SW wind 10 kt. Seas 2 ft. Patchy morning fog.
.SAT NIGHT...SE wind 15 kt. Seas 3 ft.
.SUN AND SUN NIGHT...SE wind 15 kt. Seas 5 ft.
.MON...E wind 20 kt. Seas 5 ft.
.TUE THROUGH WED...SE wind 15 kt. Seas 4 ft.

$$

PKZ165-021130-
Port Heiden to Cape Sarichef-
255 PM AKDT Fri Jun 1 2018

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

.TONIGHT...Variable wind 10 kt becoming SE 20 kt after midnight. 
From Port Moller E, variable 10 kt. Seas 4 ft.
.SAT...SE wind 30 kt except S 20 kt from Port Moller E. Seas 7 ft. 
Rain.
.SAT NIGHT...S wind 25 kt decreasing to 15 kt after midnight. Seas 7
ft.
.SUN...Variable wind 10 kt. Seas 9 ft.
.SUN NIGHT...E wind 15 kt. Seas 9 ft.
.MON THROUGH WED...E wind 15 kt. Seas 6 ft.

$$

PKZ170-021130-
Cape Sarichef to Nikolski Bering Side-
255 PM AKDT Fri Jun 1 2018

...GALE WARNING SATURDAY...

.TONIGHT...SE wind 15 kt increasing to 30 kt after midnight. Seas 7 
ft. Rain.
.SAT...SE wind 35 kt. Seas 10 ft. Rain.
.SAT NIGHT...SW wind 25 kt. Seas 13 ft.
.SUN AND SUN NIGHT...S wind 20 kt. Seas 11 ft.
.MON...S wind 20 kt. Seas 8 ft.
.TUE...SW wind 15 kt. Seas 7 ft.
.WED...NW wind 15 kt. Seas 5 ft.

$$

PKZ171-021130-
Unalaska Bay-
255 PM AKDT Fri Jun 1 2018

...SMALL CRAFT ADVISORY THROUGH SATURDAY...

.TONIGHT...SE wind 15 kt increasing to 25 kt after midnight. Seas
3 ft. Rain.
.SAT...SE wind 25 kt. Gusts to 40 kt. Seas 4 ft. Rain.
.SAT NIGHT...SW wind 10 kt. Seas 2 ft.
.SUN AND SUN NIGHT...S wind 10 kt. Seas 2 ft.
.MON THROUGH TUE...SW wind 10 kt. Seas 2 ft.
.WED...W wind 10 kt. Seas 2 ft.

$$

PKZ172-021130-
Cape Sarichef to Nikolski Pacific Side-
255 PM AKDT Fri Jun 1 2018

...GALE WARNING SATURDAY...

.TONIGHT...S wind 15 kt increasing to 25 kt after midnight. Seas 7 
ft.
.SAT...S wind 35 kt becoming SW 25 kt in the afternoon. Seas 11 ft. 
Rain.
.SAT NIGHT...SW wind 25 kt decreasing to 15 kt after midnight. Seas 
12 ft.
.SUN...S wind 15 kt. Seas 12 ft.
.SUN NIGHT...S wind 20 kt. Seas 8 ft.
.MON THROUGH WED...W wind 20 kt. Seas 10 ft.

$$

PKZ173-021130-
Nikolski to Seguam Island Bering Side-
255 PM AKDT Fri Jun 1 2018

...GALE WARNING THROUGH SATURDAY...

.TONIGHT...S wind 30 kt increasing to 40 kt after midnight. Seas
7 ft building to 12 ft after midnight. Rain.
.SAT...S wind 40 kt becoming SW 30 kt in the afternoon. Seas 13
ft. Rain.
.SAT NIGHT...SW wind 30 kt. Seas 15 ft.
.SUN...S wind 20 kt. Seas 13 ft.
.SUN NIGHT...S wind 25 kt. Seas 9 ft.
.MON...W wind 20 kt. Seas 8 ft.
.TUE THROUGH WED...NW wind 15 kt. Seas 7 ft.

$$

PKZ174-021130-
Nikolski to Seguam Island Pacific Side-
255 PM AKDT Fri Jun 1 2018

...GALE WARNING THROUGH SATURDAY...

.TONIGHT...S wind 30 kt increasing to 40 kt after midnight. Seas
7 ft building to 12 ft after midnight. Rain.
.SAT...S wind 35 kt becoming SW 30 kt in the afternoon. Seas 17 ft. 
Rain.
.SAT NIGHT...SW wind 25 kt. Seas 17 ft.
.SUN...SW wind 15 kt. Seas 13 ft.
.SUN NIGHT...SW wind 25 kt. Seas 10 ft.
.MON THROUGH TUE...W wind 25 kt. Seas 12 ft.
.WED...W wind 20 kt. Seas 8 ft.

$$

PKZ175-021130-
Seguam Island to Adak Bering Side-
255 PM AKDT Fri Jun 1 2018

...GALE WARNING THROUGH SATURDAY...

.TONIGHT...SE wind 30 kt increasing to 45 kt by midnight. Seas 13 
ft. Rain.
.SAT...SW wind 35 kt. Seas 20 ft.
.SAT NIGHT...SW wind 30 kt. Seas 19 ft.
.SUN...SW wind 25 kt. Seas 13 ft.
.SUN NIGHT...SW wind 25 kt. Seas 9 ft.
.MON...W wind 25 kt. Seas 10 ft.
.TUE THROUGH WED...NW wind 20 kt. Seas 9 ft.

$$

PKZ176-021130-
Seguam Island to Adak Pacific Side-
255 PM AKDT Fri Jun 1 2018

...GALE WARNING THROUGH SATURDAY...

.TONIGHT...SE wind 30 kt increasing to 45 kt by midnight. Seas 16 
ft. Rain.
.SAT...SW wind 40 kt. Seas 24 ft.
.SAT NIGHT...SW wind 30 kt. Seas 20 ft.
.SUN...SW wind 25 kt. Seas 13 ft.
.SUN NIGHT...SW wind 30 kt. Seas 13 ft.
.MON THROUGH TUE...W wind 25 kt. Seas 13 ft.
.WED...W wind 20 kt. Seas 8 ft.

$$

PKZ177-021130-
Adak to Kiska-
255 PM AKDT Fri Jun 1 2018

...STORM WARNING TONIGHT...

.TONIGHT...S wind 50 kt becoming SW 45 kt by midnight. Bering side, 
seas 21 ft. Pacific side, seas 22 ft building to 29 ft after 
midnight. Widespread rain showers.
.SAT...SW wind 45 kt. Seas 24 ft Bering side... 30 ft Pacific side.
.SAT NIGHT...SW wind 35 kt decreasing to 25 kt by midnight. Seas 20 
ft.
.SUN AND SUN NIGHT...W wind 30 kt. Seas 14 ft.
.MON...W wind 30 kt. Seas 14 ft.
.TUE...NW wind 25 kt. Seas 11 ft.
.WED...NW wind 20 kt. Seas 8 ft.

$$

PKZ178-021130-
Kiska to Attu-
255 PM AKDT Fri Jun 1 2018

...STORM WARNING TONIGHT...

.TONIGHT...S wind 40 kt becoming W 50 kt by midnight. Seas 21 ft 
Bering side...29 ft Pacific side. Widespread rain showers.
.SAT...W wind 45 kt. Seas 27 ft.
.SAT NIGHT...SW wind 35 kt decreasing to 25 kt after midnight. Seas 
19 ft.
.SUN AND SUN NIGHT...W wind 30 kt. Seas 14 ft.
.MON...W wind 25 kt. Seas 13 ft.
.TUE THROUGH WED...NW wind 20 kt. Seas 9 ft.

$$

PKZ179-021130-
Pribilof Islands Near Shore Waters-
255 PM AKDT Fri Jun 1 2018

...GALE WARNING SATURDAY...

.TONIGHT...SE wind 20 kt increasing to 30 kt after midnight. Seas 9 
ft. Rain.
.SAT...SE wind 35 kt. Seas 14 ft. Rain.
.SAT NIGHT...SW wind 25 kt. Seas 16 ft. Rain showers.
.SUN...S wind 20 kt. Seas 16 ft.
.SUN NIGHT...SE wind 20 kt. Seas 11 ft.
.MON THROUGH TUE...NE wind 15 kt. Seas 8 ft.
.WED...N wind 15 kt. Seas 4 ft.

$$

PKZ180-021130-
Kuskokwim Delta and Etolin Strait-
255 PM AKDT Fri Jun 1 2018

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

.TONIGHT...S wind 20 kt. Seas 3 ft.
.SAT...SE wind 30 kt. Seas 7 ft.
.SAT NIGHT...SE wind 30 kt. Seas 9 ft. Rain.
.SUN...S wind 20 kt. Seas 8 ft.
.SUN NIGHT...SE wind 15 kt. Seas 8 ft.
.MON...E wind 20 kt. Seas 6 ft.
.TUE THROUGH WED...E wind 15 kt. Seas 5 ft.

$$

PKZ181-021130-
North and West of Nunivak Island-
255 PM AKDT Fri Jun 1 2018

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

.TONIGHT...SE wind 15 kt increasing to 25 kt after midnight. Seas 5 
ft.
.SAT...SE wind 30 kt. Seas 10 ft.
.SAT NIGHT...SE wind 30 kt. Seas 12 ft.
.SUN...SE wind 25 kt. Seas 10 ft.
.SUN NIGHT...SE wind 15 kt. Seas 9 ft.
.MON THROUGH WED...NE wind 15 kt. Seas 6 ft.

$$

PKZ185-021130-
Saint Matthew Island Waters-
255 PM AKDT Fri Jun 1 2018

...GALE WARNING THROUGH SATURDAY NIGHT...

.TONIGHT...E of Saint Matthew Island, SE wind 15 kt increasing to 30
kt after midnight. W of Saint Matthew Island, SE wind 30 kt 
increasing to 40 kt after midnight. Seas 13 ft. Rain.
.SAT...SE wind 40 kt. Seas 18 ft.
.SAT NIGHT...SE wind 35 kt. Seas 19 ft. Rain showers.
.SUN...SE wind 30 kt. Seas 17 ft.
.SUN NIGHT...SE wind 25 kt. Seas 13 ft.
.MON THROUGH WED...NE wind 20 kt. Seas 7 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
440 PM AKDT Thu May 31 2018

.ANALYSIS AND UPPER LEVELS...
The large scale synoptic pattern features an elongating upper
level low over the eastern Bering Sea with a couplet of weak upper
lows over interior Alaska. A developing low over the Gulf of
Alaska is forming along the base of a 110 knot jet stream in the
vicinity of 45N. farther west, a well defined high cirrus shield
on satellite imagery is nosing south of Kamchatka. This is
associated with a strong subtropical jet and associated
subtropical warm front. Over Southern Alaska, with weak
forcing/flow, diurnal heating has helped spark some inland
showers.

&&

.MODEL DISCUSSION...
The numerical models have settled into good agreement with both
the large scale pattern and the low tracks. The most significant
low is the powerful 963-965 hpa bomb cyclone expected to move into
the western Bering Sea Friday and Friday night. The models are
now clustered tightly and all depict a brief period of storm force
winds as the low rapidly deepens. The GFS was favored for this
storm. The one area of inconsistency in the models is where the
best thunderstorm potential is Friday and Saturday as temperatures
warm inland across all of Southern Alaska. This is common in the
models when convective forcing is present, so for this forecast a
blend of the higher resolution models will be favored since most
of the convective forcing will be related to the mountainous
terrain.

&&

.AVIATION...
PANC...VFR conditions and light diurnal winds are expected to
persist through the TAF period.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2: Friday and
Saturday)...
A pattern change is underway across Southcentral for the short
term period as light easterly flow develops in the upper levels,
which for a time will shut off the influx of clouds and moisture
into the area in favor of warmer and drier conditions. This
evening, we are in the transition period where some areas have
persisted with some leftover stratus, while many other areas that
have picked up some sunshine are getting showers. An isolated
thunderstorm or two have occurred along the east side of the
Talkeetna Mountains. The shower and thunderstorm activity will
diminish late this evening as solar heating diminishes and can no
longer support the convective activity.

On Friday, offshore flow developing with northeasterly flow
throughout the atmosphere over much of Southcentral will promote
drier conditions. As a result, much of the area should start the
day with plentiful sunshine into mid-morning, after which point
showers and thunderstorms will redevelop. Again, the greatest
density of storm activity will be focused north of Anchorage
across the Susitna Valley and Copper River Basin. What will make
Friday unique is that the northeast flow will allow the showers
and storms that originate over the mountains to move southwestward
off the mountains, which could allow Anchorage and the Matanuska
Valley to get in on a thunderstorm or two. However, nearly all of
mainland Southcentral should at least see some convective showers
around for a time Friday afternoon and evening. While more storms
are expected on Friday, a lack of any well defined upper level
features should keep the storms disorganized, so no impacts
resulting in damage are expected. Once again Friday night, the
convective activity will diminish.

Saturday should be a similar day to Friday as regards shower and
storm development and timing. The upper level wind flow should
turn back to broad easterly, and warming upper level temperatures
may help to diminish the intensity of the showers and storms
somewhat as compared with Friday. The best chance of storms again
will be in the Talkeetnas, but mountains further east including
the Wrangells should see more storms Saturday in association with
a weak upper wave. The coverage of storms will be greater on
Saturday than Friday due to the strengthening thermal trough over
the interior.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
A weakening low pressure system in the eastern Bering will
continue to slide southeast overnight. As it does, showers along
the west coast will come to an end. As the upper-level pattern
progresses east tomorrow, an offshore flow will develop and the
thermal trough will reestablish itself. This will allow diurnal
convection in the form of scattered showers and isolated
thunderstorms to initiate across the interior regions of southwest
Alaska Friday afternoon and evening. Convective development is
also possible again Saturday afternoon, but it should remain
limited to the higher terrain as the thermal trough is shunted
east as a moist onshore develops ahead of the next front late
Saturday.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
A weakening low will continue to support scattered showers across
the eastern half of the Bering through the early morning hours
Friday. Also on Friday, an unseasonably strong 965 mb surface low
will move into the western Bering. A warm front extending ahead of
the low will bring periods of moderate rain to the western and
central Aleutians. This front will also be strong enough to
produce a wide swath of gale-force winds, and perhaps a narrow
band of storm-force winds as it treks across the western Aleutians
tomorrow. Another round of strong gale force winds will develop
over the western Aleutians Friday night into early Saturday as
colder air wraps in around the back side of the low. As the low
continues into the northern Bering, its associated front will
occlude and weaken as it approaches the Alaska Peninsula Saturday
evening.

&&

.LONG TERM FORECAST (Days 3 through 7)...
At the beginning of next week the longwave trough over the Bering
broadens its coverage across much of Alaska and the Gulf as the
parent low currently across the eastern gulf shears apart. The
main low center within the trough centers near the eastern
Aleutians for the duration of the week. The main concern is
thunderstorm potential along a thermal ridge which sets up across
the interior and southern Alaska. Otherwise, cloudy and wet
conditions are expected across the Gulf and Bering with seasonally
warm conditions and afternoon/ evening showers inland.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Storm Warning 177.
 Gale Warning 173>176 178 185.

&&

SYNOPSIS AND MODEL DISCUSSION...JA
SOUTHCENTRAL ALASKA...JW
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...TM
LONG TERM...KH