Gale Warning 631, NWS Anchorage, AK

355 
FZAK62 PAFC 070027
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
327 PM AKST Tue Nov 6 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.

PKZ499-071415-
327 PM AKST Tue Nov 6 2018
.SYNOPSIS FOR CENTRAL BERING SEA...

A 994 mb low at 62N 171W moves inland Wed morning. A 990 mb
Kamchatka low moves to 60N 178W Thu afternoon at 983 mb.

$$

PKZ411-071415-
Bering Sea Offshore West of 180 and East of the International
Dateline-
327 PM AKST Tue Nov 6 2018

...STORM WARNING WEDNESDAY NIGHT...

.TONIGHT...W wind 10 to 20 kt becoming SW 15 to 30 kt after
midnight. Seas 7 to 11 ft.
.WED...S wind 25 to 40 kt. Seas 9 to 14 ft. Widespread rain
showers.
.WED NIGHT...W wind 35 to 50 kt. Seas 16 to 31 ft. Rain and snow 
showers.
.THU...W wind 35 to 50 kt. Seas 21 to 33 ft.
.THU NIGHT...W wind 30 to 45 kt. Seas 16 to 29 ft.
.FRI THROUGH SUN...N wind 15 to 30 kt. Seas 11 to 19 ft.

$$

PKZ412-071415-
Bering Sea Offshore 171W to 180 and North of 56N-
327 PM AKST Tue Nov 6 2018

...GALE WARNING WEDNESDAY NIGHT...

.TONIGHT...W wind 20 kt. Seas 10 to 15 ft.
.WED...SW wind 10 to 20 kt becoming S 15 to 30 kt in the
afternoon. Seas 8 ft.
.WED NIGHT...S wind 20 to 35 kt. Seas 9 to 17 ft. Rain showers.
.THU...SW wind 30 to 45 kt. Seas 16 to 31 ft.
.THU NIGHT...W wind 30 to 45 kt. Seas 22 to 34 ft.
.FRI...SW wind 15 to 30 kt. Seas 14 to 22 ft.
.SAT...NW wind 10 to 25 kt. Seas 6 to 11 ft.
.SUN...N wind 20 to 30 kt. Seas 12 to 20 ft.

$$

PKZ413-071415-
Bering Sea Offshore 171W to 180 and South of 56N-
327 PM AKST Tue Nov 6 2018

...GALE WARNING WEDNESDAY AND WEDNESDAY NIGHT...

.TONIGHT...W wind 20 kt. Seas 9 to 14 ft.
.WED...SW wind 10 to 20 kt becoming S 20 to 35 kt in the
afternoon. Seas 7 to 11 ft.
.WED NIGHT...SW wind 20 to 35 kt. Seas 7 to 12 ft building to 10
to 18 ft after midnight. Rain.
.THU...W wind 30 to 40 kt. Seas 14 to 29 ft.
.THU NIGHT...W wind 25 to 40 kt. Seas 18 to 29 ft.
.FRI...W wind 15 to 30 kt. Seas 13 to 20 ft.
.SAT THROUGH SUN...N wind 15 to 30 kt. Seas 12 to 20 ft.

$$

PKZ414-071415-
Bering Sea Offshore East of 171W-
327 PM AKST Tue Nov 6 2018

.TONIGHT...W wind 10 to 20 kt. Seas 9 to 15 ft.
.WED...W wind 10 to 15 kt. Seas 8 ft.
.WED NIGHT...SW wind up to 20 kt becoming S 15 to 30 kt after
midnight. Seas 5 to 10 ft. Rain.
.THU...SW wind 20 to 30 kt. Seas 9 to 14 ft.
.THU NIGHT...W wind 25 to 35 kt. Seas 15 to 23 ft.
.FRI...SW wind 15 to 30 kt. Seas 12 to 20 ft.
.SAT...SW wind up to 15 kt. Seas 6 to 11 ft.
.SUN...N wind 25 kt. Seas 8 to 13 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion...CORRECTED
National Weather Service Anchorage AK
633 PM AKST Mon Nov 5 2018

Update to Longterm Discussion

.ANALYSIS AND UPPER LEVELS...
The axis of the upper level ridge is moving over Southcentral
Alaska late this afternoon with and upper level low close to the
Gulf of Anadyr in eastern Russia. A decent jet streak which is
running a little over 100 KT (from the south-southwest) is in
between these two features.
At the surface, high pressure remains over the mainland part of
the state including Southcentral ALaska. Southwest Alaska is
beginning to be impacted by the front associated the a fairly
strong low in the northwest Bering Sea which is moving eastward.
This low and the front will have a difficult time progressing too
far eastward due to the ridge, but will also weaken it to set the
stage for a low, which is currently over 500 miles south of Sand
Point, to move into the Gulf of Alaska later in the week and
eventually displace the ridge.

&&

.MODEL DISCUSSION...
Models are in good synoptic agreement through mid-week, but there
are some differences emerging by the time Thursday arrives that
are worth noting. There are still some small differences with the
timing and track of the low approaching the Gulf of Alaska
Wednesday and Thursday as noted on the early morning discussion.
However, the differences seem to have lessened and models are
converging an a common solution increasing forecast confidence
with this low.
The low currently moving through the Bering Sea looks to be
locked-on by all models. It is the second low moving through a
similar track Wednesday night through Friday in which there is
much larger disagreement. In particular, the EC is a bit faster
and farther to the southeast than other models. The GFS and NAM
solutions are very similar to each other and taking a more
favorable northerly track so forecasts are more reflective of
those solutions.

&&

.AVIATION...
PANC...VFR conditions and light winds will persist. There may be
some small areas of stratus overnight in the vicinity, but a
ceiling at the airport is not expected.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
A ridge persists across the southern mainland through mid week,
keeping inland areas cool and dry. A front moves up to the
southern Gulf Tuesday afternoon spreading rain across Kodiak
Island Tuesday night through Wednesday. Gale easterly winds are
expected along the boundary across the Gulf with northerly flow
for the Cook Inlet and Shelikof Strait on the backside of the
occlusion.

Precipitation type is challenging along the eastern Kenai
Peninsula as models are showing slight differences in the track
of the low. The front is expected to push across the eastern coast
of the Kenai Peninsula Wednesday morning; with a cold air mass in
place at the onset of the front, precipitation is expected to
start as snow. The low level temperatures slowly moderate to just
above freezing during the afternoon which may change precipitation
briefly over to rain.

&&

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

Scattered light rain showers will continue to fall over the
Kuskokwim Delta in advance of a front sliding toward the coast
from the eastern Bering. This front will move onshore overnight,
pushing into the interior tomorrow before slowing and shearing
apart tomorrow night as a low south of the AKPEN tracks north
toward Kodiak Island. A few rain and snow showers will linger
into Wednesday, especially along the higher terrain of the Alaska
and Aleutian Ranges. A fast-moving ridge then slides over the
southwest late Wednesday remaining in place over the interior
through Thursday. The next frontal system slides toward the coast
Thursday as a deep low moves east across the Bering. This front
will race onshore quickly, so precipitation amounts will be rather
light. However, with colder air in place, precipitation with this
frontal system will fall primarily as snow. Accumulations of
around one inch are possible for locations such as Bethel and
Dillingham. Scattered snow showers will linger behind the front
for Thursday night into early Friday.

&&

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

A storm-force low continues to track northeast toward the central
Bering this afternoon. As it does, the storm-force winds will
subside, but a wide area of gales will remain west of the
Pribilofs. Steep lapse rates due to colder air aloft wrapping
around the low combined with strong instability accompanying the
upper low will also bring the potential for some isolated
thunderstorms along the southern periphery of the low. This system
then weakens as it becomes vertically stacked and gradually lifts
toward Saint Lawrence Island tomorrow. The next Kamchatka low
then moves away from eastern Russia by late Tuesday swinging a
frontal system across the western Aleutians. The front then
quickly occludes as it races east, sweeping over the central
Aleutians by Wednesday and the eastern Aleutians Wednesday night
into early Thursday. Southerly gales will accompany the front as
it moves over the Aleutians and Pribilofs through the forecast
period. Storm-force winds will also develop over the western
Bering late wednesday into Thursday as the low deepens and tracks
toward Saint Matthew Island.

&&

.LONG TERM FORECAST (Days 3 through 7)...

An active pattern will be on tap for the west domain Thursday to
Monday. At the onset of the forecast period, there is a storm
south of the Aleutian chain and a mature system with a triple
point low in the Bering. Additionally, there is a disturbance near
Kodiak. There are some minor differences with timing and the
tracks of of the lows as early as F72 and F96. However, as time
elapses, the differences significantly amplify. With the longwave
trough in place over the Bering and the North Pacific, very
confident in the level of persistent unsettledness for the Bering,
the Aleutians and Southwest Alaska. However, given the lack of
run to run continuity there seems to be more uncertainty in the
longterm for Southcentral Alaska including Prince William Sound.
Waiting for the details to flesh out beyond F96.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Storm 411. Gales 132 178 181 185 351 352 412 413.

&&

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