Storm Warning 127, NWS Anchorage, AK

231 
FZAK62 PAFC 221238
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
338 AM AKST Thu Nov 22 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.

PKZ499-230145-
338 AM AKST Thu Nov 22 2018
.SYNOPSIS FOR CENTRAL BERING SEA...
A 976 mb low at 49N 178W will remain nearly stationary through Fri
afternoon. The low will then move to 49N 171W at 956 mb Sat
morning. 

$$

PKZ411-230145-
Bering Sea Offshore West of 180 and East of the International
Dateline-
338 AM AKST Thu Nov 22 2018

...GALE WARNING THROUGH FRIDAY...

.TODAY...E wind 25 to 35 kt. Seas 11 to 19 ft. Rain.
.TONIGHT...NE wind 25 to 35 kt. Seas 13 to 21 ft. Rain and snow.
.FRI...NE wind 30 to 40 kt. Seas 15 to 22 ft. Snow and rain showers.
.FRI NIGHT...NE wind 30 to 40 kt. Seas 17 to 23 ft.
.SAT THROUGH SUN...N wind 20 to 35 kt. Seas 12 to 20 ft.
.MON...NW wind 10 to 25 kt. Seas 8 to 13 ft.

$$

PKZ412-230145-
Bering Sea Offshore 171W to 180 and North of 56N-
338 AM AKST Thu Nov 22 2018

...GALE WARNING TONIGHT AND FRIDAY...

.TODAY...E wind 15 to 30 kt. Seas 6 to 13 ft.
.TONIGHT...NE wind 25 to 35 kt. Seas 9 to 17 ft.
.FRI...NE wind 35 kt. Seas 12 to 19 ft. Snow and rain.
.FRI NIGHT...NE wind 35 kt. Seas 12 to 19 ft.
.SAT THROUGH MON...NW wind 25 to 35 kt. Seas 10 to 18 ft.

$$

PKZ413-230145-
Bering Sea Offshore 171W to 180 and South of 56N-
338 AM AKST Thu Nov 22 2018

...STORM WARNING THROUGH TONIGHT...

.TODAY...E wind 25 to 40 kt increasing to 35 to 50 kt in the
afternoon. Seas 11 to 19 ft.
.TONIGHT...NE wind 35 to 50 kt diminishing to 30 to 40 kt after
midnight. Seas 15 to 21 ft. Rain and snow.
.FRI...NE wind 25 to 40 kt. Seas 13 to 21 ft. Rain and snow.
.FRI NIGHT...NE wind 25 to 40 kt. Seas 12 to 20 ft.
.SAT THROUGH MON...NW wind 20 to 35 kt. Seas 11 to 19 ft.

$$

PKZ414-230145-
Bering Sea Offshore East of 171W-
338 AM AKST Thu Nov 22 2018

...GALE WARNING TONIGHT...

.TODAY...E wind 15 to 30 kt. Seas 6 to 11 ft.
.TONIGHT...E wind 20 to 35 kt. Seas 7 to 12 ft. Rain.
.FRI...E wind 15 to 30 kt. Seas 7 to 11 ft. Rain.
.FRI NIGHT...E wind 15 to 30 kt. Seas 7 to 12 ft.
.SAT...NE wind 10 to 25 kt. Seas 7 to 12 ft.
.SUN...N wind 15 to 30 kt. Seas 9 to 14 ft.
.MON...NW wind 20 to 30 kt. Seas 7 to 12 ft.

$$

389 
FZAK62 PAFC 230019
OFFALU

Offshore Waters Forecast
National Weather Service Anchorage AK
319 PM AKST Thu Nov 22 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.

PKZ499-231400-
319 PM AKST Thu Nov 22 2018
.SYNOPSIS FOR CENTRAL BERING SEA...

A 966 mb low at 51N 176W loops to 47N 176W at 969 mb for Sat
afternoon. Its front arches across the Bering and Alaska Peninsula
into the Gulf of Alaska through Sat afternoon. A 970 mb low near
46N 163E tracks to 49N 166W at 959 mb by Sat afternoon.

$$

PKZ411-231400-
Bering Sea Offshore West of 180 and East of the International
Dateline-
319 PM AKST Thu Nov 22 2018

...GALE WARNING THROUGH FRIDAY NIGHT...

.TONIGHT...NE wind 25 to 35 kt. Seas 13 to 20 ft. Rain and snow.
.FRI...NE wind 30 to 40 kt. Seas 15 to 22 ft. Rain showers.
.FRI NIGHT...NE wind 30 to 40 kt. Seas 17 to 22 ft. Snow showers and
rain showers.
.SAT...NE wind 25 to 35 kt. Seas 14 to 20 ft.
.SAT NIGHT...N wind 20 to 30 kt. Seas 13 to 16 ft.
.SUN THROUGH TUE...N wind 10 to 25 kt. Seas 9 to 14 ft.

$$

PKZ412-231400-
Bering Sea Offshore 171W to 180 and North of 56N-
319 PM AKST Thu Nov 22 2018

...GALE WARNING THROUGH FRIDAY NIGHT...

.TONIGHT...NE wind 25 to 35 kt. Seas 10 to 18 ft.
.FRI...NE wind 30 to 40 kt. Seas 13 to 20 ft. Rain.
.FRI NIGHT...NE wind 35 kt. Seas 13 to 19 ft.
.SAT...NE wind 30 kt. Seas 12 to 16 ft.
.SAT NIGHT...N wind 30 kt. Seas 11 to 15 ft.
.SUN THROUGH TUE...NW wind 15 to 30 kt. Seas 10 to 16 ft.

$$

PKZ413-231400-
Bering Sea Offshore 171W to 180 and South of 56N-
319 PM AKST Thu Nov 22 2018

...GALE WARNING THROUGH FRIDAY NIGHT...

.TONIGHT...NE wind 30 to 45 kt. Seas 15 to 22 ft. Rain with snow.
.FRI...NE wind 25 to 40 kt. Seas 14 to 22 ft. Rain.
.FRI NIGHT...NE wind 20 to 35 kt. Seas 11 to 19 ft.
.SAT...NE wind 25 to 35 kt. Seas 11 to 18 ft.
.SAT NIGHT...N wind 25 to 35 kt. Seas 12 to 17 ft.
.SUN THROUGH TUE...NW wind 15 to 30 kt. Seas 11 to 17 ft.

$$

PKZ414-231400-
Bering Sea Offshore East of 171W-
319 PM AKST Thu Nov 22 2018

...GALE WARNING TONIGHT...

.TONIGHT...E wind 20 to 35 kt. Seas 7 to 12 ft. Rain.
.FRI...E wind 15 to 30 kt. Seas 8 to 13 ft. Rain.
.FRI NIGHT...E wind 15 to 30 kt. Seas 7 to 12 ft.
.SAT...E wind 10 to 25 kt. Seas 5 to 10 ft.
.SAT NIGHT...NE wind 15 to 25 kt. Seas 5 to 10 ft.
.SUN THROUGH TUE...W wind 15 to 30 kt. Seas 8 to 13 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
454 AM AKST Wed Nov 21 2018

.ANALYSIS AND UPPER LEVELS...

A vertically stacked low is traveling southeastward from Mekoryuk
Island to the Lower Kuskokwim Delta. A negatively tilted, long
wave trough extends over mainland Alaska and over the entire Gulf
of Alaska. At 300 mb, the jet stream is oriented northwesterly-
southeasterly over the eastern Aleutians with a 120 kt streak
skirting the Aleutian chain. Increased vorticity is present in the
area of the low and the jet streak over the eastern Aleutians. A
front is moving over the western Aleutians which can be observed
in satellite imagery. Sandwiched between the long wave trough and
the incoming front, a ridge is quickly building over the Bering
Sea. The Bering remains relatively cloud free with mostly cumulus
present under the ridge and corresponding surface high pressure.
Stratus is making its way into the western Bering with the
associated front. Mainland Alaska is generally covered in stratus
and scattered precipitation as seen on radar imagery. In the
northern Gulf of Alaska, the low is in its final stages of
occlusion as it moves inland over eastern Prince William Sound.
Northerly flow continues to increase across the mainland advecting
a deep layer of cold air over the northern and western parts of
the state. Patchy clearing over Southcentral is leading to
increased surface cooling causing fog to persist for locations
along the the Cook Inlet/Kink Arm this morning. Thus, the Dense
Fog Advisory will continue for Anchorage through noon on
Wednesday.

&&

.MODEL DISCUSSION...

No major model discrepancies were noted in the short term with
decent consensus on the significant features impacting the area.
Some fairly significant differences begin to show up by the
weekend with the arrival of the next major system into the Gulf of
Alaska from the North Pacific. The NAM seems to be the outlier
right now as it depicts a 975 mb surface low moving north over
Kodiak Saturday morning with an associated front pushing across
the Gulf Coast later in the day. The EC/GFS are in better
agreement and keep the low out over the southern Gulf with a later
arrival of the front to the coast. The current forecast leans
towards the later solution.

&&

.AVIATION...

Dense fog is expected to persist through most of the day today
with little change in the overall pattern expected. There could
be some temporary improvement and lifting of the fog later this
afternoon but weak winds and a strengthening surface inversion as
ridging builds in from the west will promote fog redevelopment tonight.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...

Stable conditions across the Anchorage Bowl/Kenai Peninsula have
given rise to fairly widespread fog. Little changes
atmospherically tonight in these areas so we may see a repeat
performance. Gusty northeasterly winds are expected over the
Matanuska Valley today and tonight, so any fog around this morning
is not likely to reappear tonight. Light snow will continue
across the Copper River Basin into the early afternoon hours. Snow
accumulations should be fairly light. Patchy fog will likely
develop in that region overnight with decreasing upper cloud
cover.

A weakening surface low retrogrades west today the dissipates
tonight. An upper level low center moves from the Southwest
Mainland to south of the Gulf tonight. In response, a broad
inverted surface trough will setup over the Gulf and encompass
several small low centers. The net effect will be increased
offshore flow with local gusty gap winds across the north Gulf
Coast and brisk northwest winds over the western Gulf. These
conditions should diminish later Thursday.

&&

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

Snow develops across Bristol Bay this morning as a surface low
slowly slides southeast to the Gulf. The upper level low driving
the front may initiate a few showers through tonight as it shears
apart. Patchy fog should improve tonight as subsidence mixes dry
air down to the surface ahead of an approaching Bering ridge. A
dry cold air mass advects across the region tonight through Friday
night bringing colder than normal temperatures for the end of the
week.

&&

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

Snow showers will develop along the eastern Bering through the
afternoon as an upper level shortwave overhead elongates on the
backside of a closed low, which exits southeast later today.
A cold dry air mass vies for dominance across the Bering
as it drops southward behind the exiting low; meanwhile, a strong
warm front pushes across the western Aleutians. The colder air
mass begins to lose its hold tonight as the subtropical jet pushes
the warm front eastward. This front will bring gusty gales along
with rain as the boundary undercuts the cold air mass across the
southern Bering; although a brief period of mixed precipitation is
possible at the onset. The front progresses to the Alaska
Peninsula and the Pribilof Islands Thursday night with a mix of
rain and snow along the boundary as it slows and re-organizes
through Friday.

&&

.LONG TERM FORECAST (Days 4 through 7: Saturday through Tuesday)...

A series of fronts and areas of low pressure are expected to
impact Southern mainland Alaska and will make for a warmer,
cloudier, and wetter second half of the Thanksgiving holiday
weekend. A front over the southern and central Gulf Saturday
morning will initiate the process of warming temperatures and
returning the area to a wet pattern. The front will track
northward into the north Gulf Coast by Saturday evening. As the
warmer air moves in, downsloping will likely help to keep
Anchorage and the surrounding areas drier, though perhaps not
entirely precipitation-free. The downsloping will also help to
quickly scour out any cold air as well. A second front will follow
right on the heels of the first for Sunday. However, by then the
models are in disagreement as to how quickly that front will move
through the Gulf into Southcentral. This is largely due to
disagreements on the track and strength of a much stronger 950 mb
low which will be centered near the Alaska Peninsula Sunday
morning. This low is likely to remain nearly stationary or follow
a looping pattern around that area, which in turn will keep
southerly flow of warm air moving into southern mainland Alaska
while winter-like cold air remains well out west over the Bering.
This pattern is likely to persist through much of the rest of the
final week of November, which will keep the area much more wet and
icy than snowy.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Dense Fog Advisory 101.
MARINE...Gales 170 172 173 174 175 176 177 178 411 413 .

&&

SYNOPSIS AND MODEL DISCUSSION...KVP/RA
SOUTHCENTRAL ALASKA...RC
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...KH
LONG TERM...JW