Storm Warning 75, NWS Anchorage, AK

907 
FZAK62 PAFC 061228
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
328 AM AKST Wed Mar 6 2019

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.

PKZ499-070145-
328 AM AKST Wed Mar 6 2019
.SYNOPSIS FOR CENTRAL BERING SEA...

A 955 mb low at 51N 172E Wed morning moves to 54N 179E at 956 mb by 
Thu morning and then to 56N 176W at 972 mb by Fri morning. A front 
approaches the western Aleutians Fri morning associated with a 960 
North Pacific low.

$$

PKZ411-070145-
Bering Sea Offshore West of 180 and East of the International
Dateline-
328 AM AKST Wed Mar 6 2019

...STORM WARNING TODAY...

.TODAY...E wind 35 to 50 kt. Seas 14 to 26 ft. Rain with snow.
.TONIGHT...NE wind 30 to 45 kt. Seas 19 to 25 ft. Rain.
.THU...N wind 20 to 35 kt. Seas 16 to 22 ft. Rain.
.THU NIGHT...N wind 15 to 30 kt. Seas 12 to 18 ft.
.FRI...NE wind 20 to 35 kt. Seas 10 to 16 ft.
.SAT...N wind 20 to 35 kt. Seas 12 to 19 ft.
.SUN...NW wind up to 20 kt. Seas 8 to 13 ft.

$$

PKZ412-070145-
Bering Sea Offshore 171W to 180 and North of 56N-
328 AM AKST Wed Mar 6 2019

...STORM WARNING TODAY...

.TODAY...E wind 35 to 50 kt. Seas 11 to 19 ft. Snow and rain.
.TONIGHT...E wind 25 to 40 kt becoming SE 20 to 30 kt after
midnight. Seas 16 to 22 ft.  Rain and snow.
.THU...E wind 20 to 30 kt. Seas 15 to 21 ft. Rain.
.THU NIGHT...E wind 15 to 30 kt. Seas 13 to 19 ft.
.FRI...E wind 20 to 35 kt. Seas 9 to 14 ft.
.SAT THROUGH SUN...NW wind 20 to 35 kt. Seas 10 to 18 ft.

$$

PKZ413-070145-
Bering Sea Offshore 171W to 180 and South of 56N-
328 AM AKST Wed Mar 6 2019

...GALE WARNING THROUGH THURSDAY...

.TODAY...SE wind 30 to 45 kt. Seas 13 to 21 ft. Snow and rain.
.TONIGHT...S wind 25 to 40 kt. Seas 15 to 25 ft. Rain.
.THU...S wind 20 to 35 kt. Seas 18 to 24 ft. Rain.
.THU NIGHT...SW wind 20 to 35 kt. Seas 14 to 22 ft.
.FRI...S wind 15 to 30 kt. Seas 9 to 17 ft.
.SAT THROUGH SUN...W wind 15 to 30 kt. Seas 11 to 19 ft.

$$

PKZ414-070145-
Bering Sea Offshore East of 171W-
328 AM AKST Wed Mar 6 2019

...GALE WARNING THROUGH TONIGHT...

.TODAY...SE wind 25 to 40 kt. Seas 8 to 13 ft. Rain.
.TONIGHT...SE wind 20 to 35 kt. Seas 8 to 16 ft. Snow with rain.
.THU...S wind 10 to 25 kt. Seas 8 to 16 ft. Rain.
.THU NIGHT...SE wind 10 to 25 kt. Seas 9 to 17 ft.
.FRI THROUGH SAT...S wind 20 to 35 kt. Seas 10 to 18 ft.
.SUN...W wind 20 to 35 kt. Seas 10 to 18 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
520 AM AKST Tue Mar 5 2019

.ANALYSIS AND UPPER LEVELS...
An impressive front is continuing to move very slowly eastward
over Southwest and into Southcentral this morning associated with
a stalled low that has moved into the eastern Bering. This front
is pushing up against the weakening ridge pattern that has shifted
slightly eastward over the Gulf and towards the Alcan border.
Precipitation observed with this front fell as snow, rain, and a
mix depending on the location over the AKPEN and coastal areas of
Southwest overnight and continuing to push inland this morning.
Over the western Bering and Aleutians, a strong 120 kt jet is in
place stretching from Shemya to Adak. A North Pacific low situated
south of the western Aleutians will be the weather feature to pay
attention to in the short term forecast. The most recent
ASCAT/Advanced Scatterometer pass has already detected both gale
and storm force winds from this new cyclone.

&&

.MODEL DISCUSSION...
The GFS, NAM and ECMWF are in lock step with the major synoptic
features through 00z Thursday. By 12z Thursday, some divergence
manifests in the models regarding the low in the Bering. The NAM
being the middle ground between the GFS and the ECMWF solutions.
Ergo, the NAM has emerged as the model of choice for the short
term forecast period.

&&

.AVIATION...
PANC...VFR conditions and light winds will persist. A cloud deck
at 5,000 ft has been observed at Merrill Field and scattered at
5,000 ft at PANC at 12:53z or 3:53 AM AST. It's possible that
this layer will actually become broken or overcast at PANC this
morning.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
Dominant ridging that has been over Southcentral Alaska will
slowly track east and weaken through tonight. Southerly flow on
the western side of the ridge will bring moisture off the Gulf,
resulting in precipitation to southern and eastern Kenai
Peninsula, Kodiak Island and areas west of Cook Inlet. Most of
these locations will see snow, but some southerly locations look
to mix with, or become, rain. Tonight, a trough will move in over
Kodiak Island from the west bringing heavier precipitation to the
area. It will then track through Southcentral Alaska on Wednesday
bringing a chance of snow to the Anchorage Bowl area. After the
trough pushes east Wednesday night precipitation will diminish,
however, some light precipitation will remain around coastal
locations and areas west of Cook Inlet.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2: Today and
Wednesday)...

A weak cold front will slowly track eastward through today aided
by an upper level jet. Snow accumulations up to 4 inches are
possible across interior regions of Southwest Alaska that stay all
snow and below freezing, with mixed precipitation or rain
continuing along the coast. Partial clearing is expected Wednesday
morning as a weak ridge builds in behind the front. As such, weak
onshore winds combined with the moisture from the previous system
may cause some patchy fog to develop late tonight into Wednesday.

&&

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

A strong low will move southwest of Attu this afternoon.
Confidence is high that associated storm force winds and high
seas will track towards the east across the western Aleutians this
evening. As the low occludes, the winds along the leading front
will diminish to gales, but will continue tracking into Bristol
Bay through Wednesday. A second area of stronger storm force
winds and very high seas will redevelop south of the low over the
western Aleutians Wednesday evening. Winds will gradually diminish
and seas subside overnight into Thursday as the surface low
weakens.

&&

.MARINE (Days 3 through 5)...

On Thursday, a storm force low tracks across the southern Bering
at 960 mb then fills quickly on Friday as it moves south of the
Pribilof Islands to the Alaska Peninsula. The next front pushes to
the western Aleutians Friday morning as a North Pacific low races
toward the Bering. The low along the southeastern waters
dissipates Friday night as the other powerful low moves toward
Kiska at 951 mb. This storm is expected to take a similar
southerly track through Saturday; however, it is expected to stay
organized as it tracks eastward. The low center does move slightly
slower as the other eastern Bering system breaks down over
Bristol Bay. The new storm center moves to near Adak at 960 mb
Saturday afternoon.

&&

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

The long range forecast beginning Thursday is an active pattern
with a storm system tracking across the southern Bering...pushing
a front across the southern mainland and the Gulf through early
Saturday. The next system to move across the Bering enters the
western Aleutian Chain on Friday night, taking a similar track
through Sunday morning. Models are generally in good agreement
with the overall synoptic pattern; however, there are important
differences with each new model run on the evolution of the low's
track over the weekend. The blends of the ensemble ECMWF and GFS
were used for updates today which continues to advertise a wetter
and windier pattern. The highest uncertainty on this low is how
far east the low tracks. Previous model runs all indicated that
the low would lift north across the eastern Bering...and now they
are showing either a triple point low developing in the Gulf or
the storm system remaining on an easterly track. Either solution
brings a forthcoming pattern change heading to the beginning of
next week.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Gales 155 165 170 171 172 173 174 179 185 412 413 414.
 		 Storms 175 176 177 178 411.

&&

SYNOPSIS AND MODEL DISCUSSION...ALH/PJS
SOUTHCENTRAL ALASKA...DK
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...AP/JPW
MARINE/LONG TERM...KH