Storm Warning 102, NWS Anchorage, AK

198 
FZAK62 PAFC 052337
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
337 PM AKDT Mon Oct 5 2020

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.

PKZ499-061330-
337 PM AKDT Mon Oct 5 2020
.SYNOPSIS FOR CENTRAL BERING SEA...

A front over the eastern Bering moves inland Tue morning. Another
front over the western Aleutians moves into the eastern Bering Tue
afternoon. The low center moves to 59N 174W at 968 mb Wed 
afternoon.

$$

PKZ411-061330-
Bering Sea Offshore West of 180 and East of the International
Dateline-
337 PM AKDT Mon Oct 5 2020

...GALE WARNING THROUGH TUESDAY NIGHT...

.TONIGHT...S wind 30 to 45 kt. Seas 7 to 12 ft building to 10 to
18 ft after midnight. Rain.
.TUE...S wind 30 to 45 kt becoming SW 20 to 35 kt in the
afternoon.
Seas 17 to 21 ft. Rain.
.TUE NIGHT...SW wind 25 to 40 kt. Seas 17 to 22 ft. Rain showers.
.WED...W wind 25 to 40 kt. Seas 17 to 24 ft.
.WED NIGHT...W wind 25 to 40 kt. Seas 15 to 22 ft.
.THU THROUGH SAT...W wind 20 to 35 kt. Seas 10 to 18 ft.

$$

PKZ412-061330-
Bering Sea Offshore 171W to 180 and North of 56N-
337 PM AKDT Mon Oct 5 2020

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

.TONIGHT...SW wind up to 20 kt becoming S 15 to 30 kt after
midnight. Seas 4 to 8 ft. Rain.
.TUE...S wind 30 to 45 kt. Seas 8 to 13 ft building to 11 to 19 ft
in the afternoon. Rain.
.TUE NIGHT...S wind 25 to 40 kt becoming SW 20 to 30 kt after
midnight. Seas 19 ft. Rain showers.
.WED...SW wind 15 to 30 kt. Seas 14 to 22 ft.
.WED NIGHT...SW wind 15 to 30 kt. Seas 15 to 21 ft.
.THU THROUGH SAT...NW wind 15 to 30 kt. Seas 8 to 16 ft.

$$

PKZ413-061330-
Bering Sea Offshore 171W to 180 and South of 56N-
337 PM AKDT Mon Oct 5 2020

...STORM WARNING TUESDAY...

.TONIGHT...SW wind 10 to 20 kt becoming S 20 to 35 kt after
midnight. Seas 5 to 10 ft.
.TUE...S wind 35 to 50 kt. Seas 11 to 19 ft. Rain.
.TUE NIGHT...SW wind 25 to 40 kt. Seas 17 to 20 ft. Rain showers.
.WED...SW wind 25 to 40 kt. Seas 16 to 23 ft.
.WED NIGHT...W wind 30 to 40 kt. Seas 18 to 22 ft.
.THU THROUGH SAT...W wind 25 to 40 kt. Seas 10 to 18 ft.

$$

PKZ414-061330-
Bering Sea Offshore East of 171W-
337 PM AKDT Mon Oct 5 2020

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

.TONIGHT...W wind 10 to 25 kt. Seas 4 to 7 ft.
.TUE...SW wind up to 20 kt becoming S 20 to 35 kt in the
afternoon. Seas 4 to 9 ft. Rain.
.TUE NIGHT...S wind 25 to 40 kt. Seas 10 to 18 ft. Rain.
.WED...SW wind 15 to 30 kt. Seas 11 to 16 ft.
.WED NIGHT...SW wind 15 to 30 kt. Seas 11 to 16 ft.
.THU THROUGH SAT...SW wind 15 to 30 kt. Seas 9 to 14 ft.

$$

543 
FZAK62 PAFC 061144
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
344 AM AKDT Tue Oct 6 2020

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.

PKZ499-070030-
344 AM AKDT Tue Oct 6 2020
.SYNOPSIS FOR CENTRAL BERING SEA...

A front over the western Aleutians moves into the eastern Bering 
by Wednesday morning then inland by Wednesday afternoon. The
associated 974 mb Kamchatka Low moves to near 61N 175W at 968 mb 
by Thursday morning.

$$

PKZ411-070030-
Bering Sea Offshore West of 180 and East of the International
Dateline-
344 AM AKDT Tue Oct 6 2020

...GALE WARNING THROUGH WEDNESDAY...

.TODAY...S to SW wind 30 to 45 kt. Seas 17 to 22 ft. Rain.
.TONIGHT...SW wind 25 to 40 kt. Seas 16 to 23 ft. Rain.
.WED...W wind 25 to 40 kt. Seas 16 to 24 ft. Rain.
.WED NIGHT...W wind 25 to 40 kt. Seas 14 to 22 ft.
.THU THROUGH SAT...NW wind 20 to 30 kt. Seas 10 to 18 ft.

$$

PKZ412-070030-
Bering Sea Offshore 171W to 180 and North of 56N-
344 AM AKDT Tue Oct 6 2020

...STORM WARNING TODAY...

.TODAY...S wind 35 to 50 kt. Seas 11 to 19 ft. Rain.
.TONIGHT...S wind 30 to 45 kt diminishing to 15 to 30 kt 
after midnight. Seas 16 to 22 ft. Rain.
.WED...SW wind 20 to 35 kt. Seas 16 to 22 ft. Rain.
.WED NIGHT...W wind 15 to 30 kt. Seas 13 to 20 ft.
.THU THROUGH FRI...W wind 15 to 30 kt. Seas 10 to 18 ft.
.SAT...N wind 15 to 25 kt. Seas 6 to 10 ft.

$$

PKZ413-070030-
Bering Sea Offshore 171W to 180 and South of 56N-
344 AM AKDT Tue Oct 6 2020

...STORM WARNING TODAY...

.TODAY...S wind 35 to 50 kt. Seas 12 to 20 ft. Rain.
.TONIGHT...SW wind 30 to 45 kt. Seas 17 to 22 ft. Rain.
.WED...SW wind 30 to 40 kt. Seas 17 to 23 ft. Rain.
.WED NIGHT...W wind 30 to 40 kt. Seas 20 to 24 ft.
.THU THROUGH FRI...W wind 25 to 40 kt. Seas 13 to 21 ft.
.SAT...W wind 20 to 30 kt. Seas 9 to 12 ft.

$$

PKZ414-070030-
Bering Sea Offshore East of 171W-
344 AM AKDT Tue Oct 6 2020

...GALE WARNING THROUGH TONIGHT...

.TODAY...S to W wind 10 to 25 kt becoming S 25 to 40 kt 
in the afternoon. Seas 5 to 10 ft. Rain.
.TONIGHT...S wind 30 to 45 kt. Seas 11 to 19 ft. Rain.
.WED...SW wind 30 kt. Seas 13 to 18 ft.
.WED NIGHT...SW wind 15 to 30 kt. Seas 12 to 19 ft.
.THU THROUGH FRI...SW wind 15 to 30 kt. Seas 10 to 18 ft.
.SAT...E wind up to 15 kt. Seas 6 to 11 ft.

$$

273 
FZAK62 PAFC 062332
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
332 PM AKDT Tue Oct 6 2020

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.

PKZ499-071300-
332 PM AKDT Tue Oct 6 2020
.SYNOPSIS FOR CENTRAL BERING SEA...

A 975 mb low near 56N 165E will move to 61N 176W at 966 mb Wed
afternoon and then remain nearly stationary and weaken to 972 mb
Thu afternoon. The front associated with this low will move from
the central Bering Sea Tue evening to the Southwest Alaska coast
Wed.

$$

PKZ411-071300-
Bering Sea Offshore West of 180 and East of the International
Dateline-
332 PM AKDT Tue Oct 6 2020

...GALE WARNING THROUGH WEDNESDAY NIGHT...

.TONIGHT...SW wind 25 to 40 kt. Seas 16 to 23 ft. Rain.
.WED...W wind 25 to 40 kt. Seas 16 to 24 ft. Rain.
.WED NIGHT...W wind 25 to 40 kt. Seas 14 to 22 ft. Rain.
.THU...NW wind 30 kt. Seas 15 to 19 ft.
.THU NIGHT...NW wind 20 to 30 kt. Seas 12 to 16 ft.
.FRI THROUGH SUN...NW wind 20 to 30 kt. Seas 9 to 15 ft.

$$

PKZ412-071300-
Bering Sea Offshore 171W to 180 and North of 56N-
332 PM AKDT Tue Oct 6 2020

...GALE WARNING THROUGH WEDNESDAY...

.TONIGHT...S wind 30 to 45 kt diminishing to 15 to 30 kt after
midnight. Seas 16 to 22 ft. Rain.
.WED...SW wind 20 to 35 kt. Seas 16 to 22 ft. Rain.
.WED NIGHT...W wind 15 to 30 kt. Seas 13 to 20 ft. Rain showers.
.THU...W wind 15 to 30 kt. Seas 13 to 18 ft.
.THU NIGHT...W wind 15 to 30 kt. Seas 10 to 18 ft.
.FRI...W wind 15 to 30 kt. Seas 9 to 14 ft.
.SAT THROUGH SUN...NW wind 15 to 25 kt. Seas 6 to 11 ft.

$$

PKZ413-071300-
Bering Sea Offshore 171W to 180 and South of 56N-
332 PM AKDT Tue Oct 6 2020

...GALE WARNING THROUGH WEDNESDAY NIGHT...

.TONIGHT...SW wind 30 to 45 kt. Seas 17 to 22 ft. Rain.
.WED...SW wind 30 to 40 kt. Seas 17 to 23 ft. Rain.
.WED NIGHT...W wind 30 to 40 kt. Seas 20 to 24 ft. Rain.
.THU...W wind 30 to 40 kt. Seas 17 to 22 ft.
.THU NIGHT...W wind 30 kt. Seas 17 ft.
.FRI THROUGH SUN...NW wind 15 to 30 kt. Seas 9 to 17 ft.

$$

PKZ414-071300-
Bering Sea Offshore East of 171W-
332 PM AKDT Tue Oct 6 2020

...GALE WARNING TONIGHT...

.TONIGHT...S wind 30 to 45 kt. Seas 11 to 19 ft. Rain.
.WED...SW wind 30 kt. Seas 13 to 18 ft.
.WED NIGHT...SW wind 15 to 30 kt. Seas 12 to 19 ft.
.THU...SW wind 15 to 30 kt. Seas 11 to 19 ft.
.THU NIGHT...SW wind 10 to 25 kt. Seas 10 to 17 ft.
.FRI...SW wind 15 to 30 kt. Seas 8 to 13 ft.
.SAT...E wind up to 15 kt. Seas 6 to 11 ft.
.SUN...NW wind 10 to 20 kt. Seas 4 to 8 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
425 PM AKDT Sun Oct 4 2020

.ANALYSIS AND UPPER LEVELS...
The pattern change is beginning with the upper level trough axis
shifting eastward over Southwest Alaska. This is in conjunction
with the 250 mb jet stream moving eastward as well. The surface
low is perfectly positioned in the upper left exit region of the
jet streak putting it near Middleton Island this afternoon.
Moisture form this low is edging back into the Cook Inlet region
after a period of mostly clear skies that brought numerous below-
freezing temperatures to Southcentral Alaska this morning.

Upper level ridging over the western Bering Sea, combined with the
trough is bringing northerly flow over the Bering. A couple of weak
surface low can also be seen on GOES-17 satellite imagery south
of the Aleutians, and another one near Unimak Pass.

&&

.MODEL DISCUSSION...

Models are in good agreement through the middle of the week. The
next system of note will be moving through the Bering from
northwest to southeast and models are in good agreement with the
movement of both the low and front associated with this low.

Models begin to struggle a bit with the potential development of
a triple point low in the Gulf of Alaska toward next weekend. The
trough axis on the GFS and EC are at least similar so that does
give us something reasonable to work with in spite of other
differences.

&&

.AVIATION...
PANC...VFR conditions and light winds will persist.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3)...

A 980 mb low over the northern Gulf continues to lift northward,
bringing rain and gusty easterly winds to the northern Gulf coast.
As this low lifts inland, rainfall will taper through Monday
morning. While there is not abundant cold air aloft, some of the
higher peaks in the Copper River Basin may see a light dusting of
snowfall overnight, especially along the southern corridor of the
Richardson Highway. By Monday morning, this low will be exiting
the area to the east and centered over the Alaska-Yukon border.
Residual showers are likely over the Prince William Sound area,
however much of Southcentral should see improving conditions and
a break from the rain on Monday, as an upper level ridge builds
in from the west. By Tuesday, weak troughing develops over the
northern Gulf, keeping scattered showers over Prince William Sound
and nearby coastal areas. Winds over the water will be minimal,
with flow expected to be below small craft levels with the
exception of winds through Kamishak Bay and across the Barren
Islands Tuesday night into Wednesday, where small craft levels are
expected.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 3)...

Scattered showers will continue near the Kuskokwim Delta coast
through Monday in onshore flow. Otherwise quiet conditions with
partly to mostly cloudy skies are expected across the rest of the
region, although showers or flurries remain possible near higher
elevations under weak upper shortwaves. Any lingering
precipitation will end by Tuesday under a ridge. Clouds will
increase Tuesday evening ahead of a front with moderate beginning
early Wednesday morning along the coast. Brief light snow is
possible farther inland, but will quickly change to rain in a
strong southerly flow.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 through 3)...

Benign conditions are expected through Monday evening over the
western Aleutians north of high pressure. Scattered showers will
persist through Monday over the central/eastern Aleutians in a
northerly flow, likewise leading to gusty winds out of bays and
passes on the Pacific side. These will gradually taper off from
west to east by Tuesday near the aforementioned high pressure. A
strong front will track over the western Bering Monday evening,
bringing gusty southerly winds (possibly storm force) and moderate
to locally heavy rain into Tuesday. It will slightly weaken as it
moves eastward into mid-week as a result of its parent low
occluding, however similar conditions are to be expected for the
central/eastern Aleutians.

&&

.MARINE (Days 3 through 5/Wednesday through Friday)...

Bering/Aleutians

Early Wednesday a low will move into the northwestern Bering,
with its front stretched across the central Bering/Aleutians. Gale
force southerlies are expected ahead of the front across the
central/eastern Bering and Aleutians. Late Wednesday, this front
rapidly heads east of the Bering with winds turning west
southwesterly and decreasing to small craft advisory levels across
the region. For Thursday and Friday the low slowly weakens near
St. Matthew island as winds across the Bering/Aleutians continue
westerly at small craft levels.

Gulf of Alaska

Light westerly flow is expected Wednesday. On Thursday winds will
flip to southerly, with small craft level winds expected across
the western Gulf. On Friday winds turn northerly and fall below
small craft levels.

&&

.LONG TERM FORECAST (Days 4 through 7/Thursday through Sunday)...

A broad upper level trough is expected to extend from the central
Bering through the Gulf of Alaska and Southcentral Thursday
through Sunday. Despite the low 500mb heights, temperatures are
not expected to be much colder as there is minimal cold air
advection expected over Southcentral Alaska due to the center of
the upper low remaining over the Bering Sea. This will result in
prevailing south-southeasterly flow across Southcentral which will
help provide moisture to produce showers through the area. The
strongest cold air advection will occur west of the upper low over
the western Bering/Aleutians. This strong cold air advection is
likely to result in Ocean-Effect showers throughout the western
Bering/Aleutians.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Flood advisory zone 121.
MARINE...Storm 178. Gales 119 120 131 177 351 352 411 413.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...EZ
SOUTHCENTRAL ALASKA...KO
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...AP
MARINE/LONG TERM...MK/ED