Small Craft Advisory 929, NWS Anchorage, AK

192 
FZAK52 PAFC 061213
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
313 AM AKST Wed Dec 6 2017

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.

PKZ199-070030-
313 AM AKST Wed Dec 6 2017
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 998 mb low 85 nm southeast of Gambell moves over Kamchatka 
tonight. A 995 mb low 200 nm west of Saint Paul moves to 270 nm
northwest of Saint Paul tonight at 993 mb and remains nearly 
stationary, weakening to 996 mb Thu night.

$$

PKZ150-070030-
South of the AK Peninsula Sitkinak to Castle Cape-
313 AM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY...

.TODAY...Variable wind 10 kt becoming E 20 kt in the afternoon.
Seas 9 ft.
.TONIGHT...NE wind 30 kt. Seas 14 ft. Rain showers.
.THU...SE wind 25 kt. Seas 13 ft.
.THU NIGHT...SE wind 15 kt. Seas 11 ft.
.FRI...E wind 25 kt. Seas 12 ft.
.SAT THROUGH SUN...E wind 20 kt. Seas 15 ft.

$$

PKZ155-070030-
South of the AK Peninsula Castle Cape to Cape Sarichef-
313 AM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY...

.TODAY...SE wind 20 kt. Seas 8 ft.
.TONIGHT...E wind 25 kt. Seas 10 ft.
.THU...NE wind 20 kt. Seas 11 ft.
.THU NIGHT...NE wind 20 kt. Seas 10 ft.
.FRI...NE wind 30 kt. Seas 14 ft.
.SAT...NE wind 25 kt. Seas 13 ft.
.SUN...E wind 15 kt. Seas 12 ft.

$$

PKZ160-070030-
Bristol Bay-
313 AM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THURSDAY...

.TODAY...S wind 15 kt. Seas 4 ft.
.TONIGHT...E wind 20 kt. Seas 4 ft. Freezing spray.
.THU...NE wind 25 kt. Seas 5 ft. Freezing spray.
.THU NIGHT...E wind 15 kt. Seas 3 ft.
.FRI THROUGH SUN...E wind 20 kt. Seas 5 ft.

$$

PKZ165-070030-
Port Heiden to Cape Sarichef-
313 AM AKST Wed Dec 6 2017

.TODAY...Variable wind 10 kt becoming SE 20 kt in the afternoon.
Seas 6 ft.
.TONIGHT...SE wind 20 kt. Seas 6 ft.
.THU...NE wind 20 kt. Seas 6 ft.
.THU NIGHT...NE wind 15 kt. Seas 5 ft.
.FRI THROUGH SAT...NE wind 25 kt. Seas 9 ft.
.SUN...NE wind 15 kt. Seas 8 ft.

$$

PKZ170-070030-
Cape Sarichef to Nikolski Bering Side-
313 AM AKST Wed Dec 6 2017

.TODAY...Variable wind 10 kt. Seas 7 ft.
.TONIGHT...E wind 20 kt. Seas 6 ft.
.THU...E wind 20 kt. Seas 6 ft.
.THU NIGHT...NE wind 20 kt. Seas 6 ft.
.FRI THROUGH SAT...N wind 30 kt. Seas 13 ft.
.SUN...NE wind 15 kt. Seas 8 ft.

$$

PKZ171-070030-
Unalaska Bay-
313 AM AKST Wed Dec 6 2017

.TODAY...Variable wind less than 10 kt. Seas 2 ft.
.TONIGHT...E wind 10 kt increasing to 20 kt after midnight. 
Seas 3 ft. Rain and snow.
.THU...E wind 15 kt becoming NE in the afternoon. Seas 3 ft.
.THU NIGHT...NE wind 15 kt. Seas 5 ft.
.FRI...N wind 30 kt. Seas 10 ft.
.SAT...N wind 25 kt. Seas 10 ft.
.SUN...NE wind 10 kt. Seas 3 ft.

$$

PKZ172-070030-
Cape Sarichef to Nikolski Pacific Side-
313 AM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY TONIGHT AND THURSDAY...

.TODAY...SE wind 15 kt. Seas 6 ft. Rain showers.
.TONIGHT...E wind 25 kt. Seas 10 ft. Rain.
.THU...E wind 25 kt. Seas 11 ft.
.THU NIGHT...NE wind 25 kt. Seas 12 ft.
.FRI...N wind 35 kt. Seas 13 ft.
.SAT...N wind 30 kt. Seas 12 ft.
.SUN...NE wind 15 kt. Seas 12 ft.

$$

PKZ173-070030-
Nikloski to Seguam Island Bering Side-
313 AM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THURSDAY...

.TODAY...SE wind 15 kt. Seas 7 ft.
.TONIGHT...E wind 20 kt. Seas 6 ft.
.THU...NE wind 25 kt. Seas 9 ft. Snow and rain.
.THU NIGHT...N wind 25 kt. Seas 8 ft.
.FRI THROUGH SAT...N wind 30 kt. Seas 14 ft.
.SUN...E wind 15 kt. Seas 9 ft.

$$

PKZ174-070030-
Nikolski to Seguam Island Pacific Side-
313 AM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY TONIGHT AND THURSDAY...

.TODAY...SE wind 20 kt. Seas 7 ft.
.TONIGHT...E wind 25 kt. Seas 10 ft. Rain and snow showers.
.THU...NE wind 30 kt. Seas 14 ft. Rain showers and snow showers.
.THU NIGHT...N wind 25 kt. Seas 14 ft.
.FRI...N wind 35 kt. Seas 16 ft.
.SAT...N wind 30 kt. Seas 16 ft.
.SUN...E wind 15 kt. Seas 16 ft.

$$

PKZ175-070030-
Seguam Island to Adak Bering Side-
313 AM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THURSDAY...

.TODAY...SE wind 20 kt. Seas 6 ft.
.TONIGHT...E wind 20 kt. Seas 6 ft.
.THU...N wind 25 kt. Seas 7 ft.
.THU NIGHT...N wind 25 kt. Seas 9 ft.
.FRI...NW wind 30 kt. Seas 13 ft.
.SAT...NE wind 25 kt. Seas 13 ft.
.SUN...E wind 20 kt. Seas 8 ft.

$$

PKZ176-070030-
Seguam Island to Adak Pacific Side-
313 AM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY...

.TODAY...SE wind 25 kt. Seas 8 ft. Snow.
.TONIGHT...E wind 25 kt. Seas 11 ft.
.THU...N wind 30 kt. Seas 12 ft.
.THU NIGHT...N wind 30 kt. Seas 12 ft.
.FRI...NW wind 35 kt. Seas 14 ft.
.SAT...N wind 30 kt. Seas 13 ft.
.SUN...E wind 25 kt. Seas 20 ft.

$$

PKZ177-070030-
Adak to Kiska-
313 AM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY...

.TODAY...E wind 25 kt. Seas 8 ft. Snow and rain showers. 
.TONIGHT...N wind 20 kt. Seas 12 ft. 
.THU...NW wind 15 kt. Seas 12 ft.
.THU NIGHT...N wind 25 kt. Seas 9 ft.
.FRI...NW wind 30 kt. Seas 13 ft.
.SAT...SE wind 30 kt. Seas 12 ft.
.SUN...E wind 25 kt. Seas 19 ft.

$$

PKZ178-070030-
Kiska to Attu-
313 AM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY...

.TODAY...NE wind 25 kt. Seas 8 ft. Freezing spray.
.TONIGHT...N wind 15 kt. Seas 11 ft.
.THU...N wind 20 kt. Seas 10 ft.
.THU NIGHT...NW wind 25 kt. Seas 11 ft.
.FRI...W wind 30 kt. Seas 12 ft.
.SAT...SE wind 40 kt. Seas 14 ft.
.SUN...E wind 30 kt. Seas 19 ft.

$$

PKZ179-070030-
Pribilof Islands Near Shore Waters-
313 AM AKST Wed Dec 6 2017

.TODAY...S wind 20 kt. Seas 7 ft.
.TONIGHT...Variable wind 10 kt. Seas 6 ft.
.THU...Variable wind 10 kt. Seas 5 ft.
.THU NIGHT...N wind 15 kt. Seas 5 ft.
.FRI THROUGH SAT...N wind 20 kt. Seas 9 ft.
.SUN...NE wind 15 kt. Seas 8 ft.

$$

PKZ180-070030-
Kuskokwim Delta and Etolin Strait-
313 AM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY TONIGHT...

.TODAY...S wind 15 kt. Seas 5 ft.
.TONIGHT...E wind 25 kt. Seas 6 ft. Freezing spray.
.THU...E wind 20 kt. Seas 6 ft. Freezing spray.
.THU NIGHT...NE wind 15 kt. Seas 5 ft.
.FRI THROUGH SAT...NE wind 20 kt. Seas 6 ft.
.SUN...NE wind 15 kt. Seas 5 ft.

$$

PKZ181-070030-
North and West of Nunivak Island-
313 AM AKST Wed Dec 6 2017

.TODAY...SW wind 15 kt. Seas 5 ft.
.TONIGHT...SE wind 20 kt. Seas 6 ft. Freezing spray.
.THU...E wind 20 kt. Seas 6 ft. Freezing spray.
.THU NIGHT...NE wind 20 kt. Seas 5 ft.
.FRI THROUGH SUN...NE wind 25 kt. Seas 7 ft.

$$

PKZ185-070030-
Saint Matthew Island Waters-
313 AM AKST Wed Dec 6 2017

.TODAY...E wind 15 kt. Seas 6 ft.
.TONIGHT...E wind 20 kt. Seas 6 ft. Freezing spray.
.THU...E wind 20 kt. Seas 7 ft. Freezing spray.
.THU NIGHT...E wind 20 kt. Seas 7 ft.
.FRI...NE wind 25 kt. Seas 7 ft.
.SAT...NE wind 25 kt. Seas 13 ft.
.SUN...NE wind 30 kt. Seas 13 ft.

$$

229 
FZAK52 PAFC 070012
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
312 PM AKST Wed Dec 6 2017

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.

PKZ199-071315-
312 PM AKST Wed Dec 6 2017
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 981 mb low 150 nm southwest of Adak moves to 425 nm south of 
Dutch Harbor at 978 mb Thu afternoon then to 370 nm south of Sand
Point by Fri afternoon. A 991 mb low 325 nm northwest of St Paul
moves to 155 nm west of St George at 1001 mb then dissipates Thu 
afternoon. A 989 mb low 380 nm south of Sand Point moves to 100 nm 
southeast of Sand Point at 982 mb by Thu afternoon then moves inland 
and dissipates.

$$

PKZ150-071315-
South of the AK Peninsula Sitkinak to Castle Cape-
312 PM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY NIGHT...

.TONIGHT...NE wind 30 kt. Seas 13 ft. Rain showers.
.THU...SE wind 25 kt. Seas 13 ft.
.THU NIGHT...S wind 20 kt. Seas 11 ft.
.FRI...E wind 25 kt. Seas 11 ft.
.FRI NIGHT...E wind 30 kt. Seas 13 ft.
.SAT THROUGH MON...SE wind 20 kt. Seas 12 ft.

$$

PKZ155-071315-
South of the AK Peninsula Castle Cape to Cape Sarichef-
312 PM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY NIGHT...

.TONIGHT...E wind 25 kt. Seas 10 ft.
.THU...NE wind 20 kt. Seas 11 ft.
.THU NIGHT...NE wind 15 kt. Seas 10 ft.
.FRI...NE wind 25 kt. Seas 11 ft.
.FRI NIGHT...NE wind 30 kt. Seas 12 ft.
.SAT...NE wind 20 kt. Seas 10 ft.
.SUN...Variable wind 10 kt. Seas 10 ft.
.MON...SE wind 20 kt. Seas 12 ft.

$$

PKZ160-071315-
Bristol Bay-
312 PM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THURSDAY...

.TONIGHT...E wind 20 kt. Seas 4 ft. Freezing spray.
.THU...NE wind 25 kt. Seas 6 ft. Freezing spray.
.THU NIGHT...E wind 20 kt. Seas 4 ft.
.FRI...E wind 15 kt. Seas 2 ft.
.FRI NIGHT...NE wind 25 kt. Seas 5 ft.
.SAT...E wind 25 kt. Seas 5 ft.
.SUN...E wind 20 kt. Seas 4 ft.
.MON...E wind 15 kt. Seas 5 ft.

$$

PKZ165-071315-
Port Heiden to Cape Sarichef-
312 PM AKST Wed Dec 6 2017

.TONIGHT...SE wind 20 kt. Seas 6 ft.
.THU...NE wind 20 kt. Seas 6 ft.
.THU NIGHT...N wind 20 kt except NE 15 kt from Port Moller E. 
Seas 6 ft.
.FRI...NE wind 20 kt. Seas 6 ft.
.FRI NIGHT...N wind 30 kt. Seas 9 ft.
.SAT...NE wind 30 kt. Seas 9 ft.
.SUN THROUGH MON...E wind 15 kt. Seas 8 ft.

$$

PKZ170-071315-
Cape Sarichef to Nikolski Bering Side-
312 PM AKST Wed Dec 6 2017

.TONIGHT...E wind 20 kt. Seas 6 ft.
.THU...E wind 20 kt. Seas 5 ft.
.THU NIGHT...N wind 20 kt. Seas 6 ft.
.FRI...N wind 25 kt. Seas 9 ft.
.FRI NIGHT...N wind 30 kt. Seas 14 ft.
.SAT...N wind 30 kt. Seas 14 ft.
.SUN THROUGH MON...NE wind 15 kt. Seas 8 ft.

$$

PKZ171-071315-
Unalaska Bay-
312 PM AKST Wed Dec 6 2017

.TONIGHT...SE wind 10 kt becoming E 20 kt after midnight. 
Seas 2 ft.
.THU...E wind 15 kt becoming NE in the afternoon. Seas 3 ft.
.THU NIGHT...N wind 20 kt. Seas 5 ft.
.FRI...N wind 25 kt. Seas 8 ft.
.FRI NIGHT...N wind 30 kt. Seas 9 ft.
.SAT...N wind 30 kt. Seas 10 ft.
.SUN...N wind 10 kt. Seas 3 ft.
.MON...E wind 10 kt. Seas 3 ft.

$$

PKZ172-071315-
Cape Sarichef to Nikolski Pacific Side-
312 PM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY NIGHT...

.TONIGHT...SE wind 20 kt. Seas 8 ft.
.THU...E wind 20 kt. Seas 10 ft.
.THU NIGHT...N wind 25 kt. Seas 11 ft.
.FRI...N wind 30 kt. Seas 11 ft.
.FRI NIGHT...N wind 35 kt. Seas 13 ft.
.SAT...N wind 35 kt. Seas 13 ft.
.SUN...Variable wind 10 kt. Seas 10 ft.
.MON...NE wind 15 kt. Seas 12 ft.

$$

PKZ173-071315-
Nikloski to Seguam Island Bering Side-
312 PM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THURSDAY NIGHT...

.TONIGHT...E wind 20 kt. Seas 5 ft.
.THU...NE wind 20 kt. Seas 7 ft.
.THU NIGHT...N wind 25 kt. Seas 7 ft.
.FRI...NW wind 30 kt. Seas 9 ft.
.FRI NIGHT...NW wind 35 kt. Seas 18 ft.
.SAT...N wind 30 kt. Seas 17 ft.
.SUN THROUGH MON...N wind 15 kt. Seas 9 ft.

$$

PKZ174-071315-
Nikolski to Seguam Island Pacific Side-
312 PM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY NIGHT...

.TONIGHT...E wind 25 kt. Seas 8 ft. Rain showers.
.THU...NE wind 25 kt. Seas 13 ft. Snow showers.
.THU NIGHT...N wind 25 kt. Seas 13 ft.
.FRI...NW wind 30 kt. Seas 13 ft.
.FRI NIGHT...NW wind 40 kt. Seas 19 ft.
.SAT...N wind 35 kt. Seas 18 ft.
.SUN...NE wind 15 kt. Seas 15 ft.
.MON...N wind 20 kt. Seas 15 ft.

$$

PKZ175-071315-
Seguam Island to Adak Bering Side-
312 PM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THURSDAY NIGHT...

.TONIGHT...E wind 20 kt. Seas 5 ft.
.THU...N wind 20 kt. Seas 6 ft.
.THU NIGHT...N wind 25 kt. Seas 7 ft.
.FRI...NW wind 30 kt. Seas 15 ft.
.FRI NIGHT...NW wind 35 kt. Seas 18 ft.
.SAT...NE wind 30 kt. Seas 13 ft.
.SUN...NE wind 25 kt. Seas 9 ft.
.MON...N wind 20 kt. Seas 12 ft.

$$

PKZ176-071315-
Seguam Island to Adak Pacific Side-
312 PM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY NIGHT...

.TONIGHT...E wind 30 kt. Seas 11 ft.
.THU...N wind 25 kt. Seas 12 ft.
.THU NIGHT...N wind 25 kt. Seas 12 ft.
.FRI...NW wind 30 kt. Seas 12 ft.
.FRI NIGHT...NW wind 35 kt. Seas 15 ft.
.SAT...NE wind 30 kt. Seas 12 ft.
.SUN...E wind 30 kt. Seas 18 ft.
.MON...N wind 20 kt. Seas 18 ft.

$$

PKZ177-071315-
Adak to Kiska-
312 PM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY NIGHT...

.TONIGHT...N wind 20 kt. Seas 12 ft.
.THU...NW wind 15 kt. Seas 12 ft.
.THU NIGHT...NW wind 25 kt. Seas 9 ft.
.FRI AND FRI NIGHT...W wind 30 kt. Seas 14 ft.
.SAT...SE wind 40 kt. Seas 16 ft.
.SUN...NE wind 30 kt. Seas 20 ft.
.MON...N wind 20 kt. Seas 20 ft.

$$

PKZ178-071315-
Kiska to Attu-
312 PM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THROUGH THURSDAY NIGHT...

.TONIGHT...N wind 15 kt. Seas 12 ft.
.THU...N wind 15 kt. Seas 9 ft.
.THU NIGHT...NW wind 25 kt. Seas 11 ft.
.FRI...W wind 25 kt. Seas 12 ft.
.FRI NIGHT...SW wind 30 kt. Seas 10 ft.
.SAT...SE wind 50 kt. Seas 20 ft.
.SUN...E wind 35 kt. Seas 21 ft.
.MON...NE wind 20 kt. Seas 21 ft.

$$

PKZ179-071315-
Pribilof Islands Near Shore Waters-
312 PM AKST Wed Dec 6 2017

.TONIGHT...Variable wind 10 kt. Seas 6 ft.
.THU...Variable wind 10 kt. Seas 4 ft.
.THU NIGHT...N wind 20 kt. Seas 5 ft.
.FRI...NW wind 20 kt. Seas 6 ft.
.FRI NIGHT...N wind 25 kt. Seas 9 ft.
.SAT...N wind 25 kt. Seas 10 ft.
.SUN...NE wind 20 kt. Seas 8 ft.
.MON...NE wind 15 kt. Seas 9 ft.

$$

PKZ180-071315-
Kuskokwim Delta and Etolin Strait-
312 PM AKST Wed Dec 6 2017

.TONIGHT...SE wind 20 kt. Seas 6 ft. Freezing spray east of a Nunivak
Island to Cape Newenham line.
.THU...NE wind 20 kt. Seas 6 ft. Freezing spray east of a Nunivak
Island to Cape Newenham line.
.THU NIGHT...NE wind 15 kt. Seas 5 ft. Freezing spray east of a Nunivak
Island to Cape Newenham line.
.FRI...NE wind 15 kt. Seas 4 ft.
.FRI NIGHT...NE wind 25 kt. Seas 5 ft.
.SAT...NE wind 25 kt. Seas 6 ft.
.SUN THROUGH MON...NE wind 20 kt. Seas 6 ft.

$$

PKZ181-071315-
North and West of Nunivak Island-
312 PM AKST Wed Dec 6 2017

...SMALL CRAFT ADVISORY THURSDAY NIGHT...

.TONIGHT...SE wind 20 kt. Seas 5 ft. Freezing spray.
.THU...E wind 20 kt. Seas 6 ft. Freezing spray.
.THU NIGHT...NE wind 25 kt. Seas 6 ft. Freezing spray.
.FRI...NE wind 20 kt. Seas 6 ft.
.FRI NIGHT...N wind 25 kt. Seas 7 ft.
.SAT THROUGH MON...N wind 25 kt. Seas 8 ft.

$$

PKZ185-071315-
Saint Matthew Island Waters-
312 PM AKST Wed Dec 6 2017

.TONIGHT...E wind 20 kt. Seas 7 ft.
.THU...E wind 20 kt. Seas 7 ft.
.THU NIGHT...NE wind 20 kt. Seas 7 ft.
.FRI AND FRI NIGHT...N wind 20 kt. Seas 7 ft.
.SAT...NE wind 25 kt. Seas 11 ft.
.SUN THROUGH MON...N wind 30 kt. Seas 16 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
524 AM AKST Tue Dec 5 2017

.ANALYSIS AND UPPER LEVELS...

A deep highly amplified trough over the Bering and eastern
Aleutians is causing plentiful active weather across Southern
Alaska this morning. Around it lies a strong jet, representing the
dividing line between warm and cold air. For southern mainland
Alaska, this means the jet is aligned nearly due south to north,
causing an amplified ridge to develop across western North America
and eastern Alaska. As Southcentral lies underneath the core of
the strongest part of the jet, it is acting as a conveyor belt for
storm after storm to track northward out of the Pacific and slam
into the north Gulf Coast. Waves in the jet are causing those
storms to target different portions of the coastline for each one,
but, in short, a very wet pattern continues for Southcentral. Over
Southwest Alaska and especially the Bering, the atmosphere is far
more unstable, and thus, more convective with cold air aloft. So
the precipitation is much more spotty. The southerly flow into
Southcentral is keeping temperatures very mild. Anchorage got to
44 degrees yesterday, remaining just shy of the record. Thus,
precipitation-type concerns remain, and can at times be entirely
dependent on the intensity of the falling precip. Meanwhile
over Southwest Alaska, more cold air in place is keeping most of
the precipitation in the form of snow.

&&

.MODEL DISCUSSION...

Continuing the pattern of the past several nights, the models are
in decent agreement through the first 24 hours or so, getting a
better handling of the next few waves of moisture tracking north
towards the Gulf Coast. Beyond that, they continue to differ
immensely, making the forecast difficult once again beyond that
time frame. In addition, the small differences between the models,
on things such as storm track, end up making a world of difference
regarding impacts to the forecast. For Anchorage for example, the
track of the low impacting Southcentral on Wednesday could mean
the difference between downsloping and warm temperatures again, or
the return of cold air and a snowfall. The difference between
those two very different solutions is just a matter of 50 miles or
so east or west. The further west, the less chance for snow and
greater for warm temperatures, and vice versa. The models are
still honing in on their chosen solution. Thus, needless to say,
much of the forecast to that level of detail remains low
confidence. Much more confidence exists in the forecast for
Southcentral to remain well above normal for temperatures, and
continue to deal with round after round of moisture from the
subtropical Pacific. Meanwhile Southwest Alaska and the Bering
will remain relatively tranquil, much more seasonable
temperature-wise, and more showery.

&&

.AVIATION...
PANC...The latest round of precipitation has largely left the
Anchorage area to the west, though a lingering shower or two is
possible through the early morning. Winds may briefly turn out of
the southeast late this afternoon and evening as a weak wave
brings the threat for additional rain and/or snow showers. The
next more major storm system moves in Wednesday morning, with snow
expected. Most indications are for the heaviest snow to begin
after 18Z, and thus the worst conditions are not yet included in
the TAF.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
An atmospheric river is aiming at the Prince William Sound area
for the next few days. The series of lows riding up this river
will kick off heavier times of precipitation. Thompson Pass will
see some of the heaviest snowfall with the greatest rates falling
between midnight tonight and late afternoon Wednesday. Snow will
mix with or turn to rain just outside Valdez which will limit snow
amounts in town there. Heavy snow is also likely to fall from
Glennallen southward in the Copper River Basin as well.
Gusty southerly winds will occur along the Copper River and will
complicate things a bit. These winds will cause limited
visibilities in blowing snow as well as bring in the possibility
of freezing rain toward Glennallen. Typically the gusty southerly
winds downslope the precipitation but the depth of the moisture
in the atmospheric river will be enough to override the full
effect of the downsloping.

Anchorage and the Matanuska Valley will be on the western
periphery of this system. What this means is that temperatures
will be cold enough for precipitation tonight and Wednesday to be
all snow. There will be a sharp edge to where the snow diminishes
and Anchorage will be near that line. Snow will likely be heavier
in the Palmer and Wasilla areas just because they are farther
east. There is a good chance that advisory level snow will fall in
both the Anchorage and Matanuska Valley from late tonight through
most of the day Wednesday. However, there is still a great amount
of uncertainty as to where the line of quickly diminishing snow
will be with models ranging by a factor of three on the amount of
snow. Therefore, will wait at least another model run to hopefully
get a better handle on where the heaviest snow will be as it is
possible the Anchorage and Matanuska Valley will see just a few
inches over the whole event. It will be that sharp of a dividing
line.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
As the gradually filling low just offshore of the Y-K Delta coast
drifts to the north-northwest today, snow showers along the
Kuskokwim Delta coast will gradually taper off. An area of
deformation will bring a fairly narrow band of moderate to
briefly heavy snow to the greater Bristol Bay area north and east
of King Salmon north to around Sleetmute.

A cold, troughy pattern will persist across Southwest Alaska
tonight through Wednesday with small shortwaves bringing
additional scattered snow showers through at times. Strong
southerly flow into the Gulf of Alaska will begin pushing a warmer
air mass up along the east side of the Aleutian Range Wednesday
night and Thursday.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
A broad trough with abundant cold air aloft will keep the Bering
and Aleutians well supplied with scattered snow showers and an
occasionally isolated thunderstorm through midweek. A north
Pacific frontal system will slide south of the western Aleutians
tonight and then continue east to be just south of the central
Aleutians on Wednesday. This low will then turn to more to the
southeast Wednesday night, tracking clear of the area Thursday.

&&

.LONG TERM FORECAST (Days 3 through 7)...
The mid/long term forecast beginning Wednesday night has ridging
over southeast Alaska with a longwave trough extending through the
Bering. In the base of the trough a low south of the Central
Aleutians will track east before dissipating. Meanwhile, multiple
waves will move up the western side of the ridging toward
Southcentral Alaska through the weekend. There is decent agreement
with the models on the overall pattern but there is inconsistency
with the timing and exact location of the various waves moving
through.

Friday night into Saturday there has been good consistency amongst
the models with a North Pacific low moving toward the Western
Aleutians. The deterministic runs all have the low rapidly
deepening to around 950 mb. However, on Sunday, models diverge
heavily with what happens to the low leading to low confidence
moving into next week.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Storm Warning: 131.
MARINE...Gale Warning: 119 125 351 352.

&&

SYNOPSIS AND MODEL DISCUSSION...JPW
SOUTHCENTRAL ALASKA...EZ
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...JR
LONG TERM...DK

SPECIAL WEATHER STATEMENT
National Weather Service ANCHORAGE AK
123 PM AKST Tue Dec 5 2017

AKZ101-111-061230-
Anchorage-Matanuska Valley-
Including the cities of Anchorage, Eagle River, Indian, Eklutna,
Palmer, Wasilla, Sutton, and Chickaloon
123 PM AKST Tue Dec 5 2017

...Update to Potential for moderate to heavy snow through
Wednesday morning...

There is potential for moderate to heavy snow to develop late
tonight across the Anchorage Bowl and Matanuska Valley, however
this system is not expected to bring accumulations as high as
previously forecast. Precipitation may start as rain or a wintry
mix before changing over to snow. Hazardous travel conditions
remain possible along area roadways through Wednesday.

As always, the latest forecast for your area can be found at
www.weather.gov/afc.