Brisk Wind Advisory 10, NWS Anchorage, AK

581 
FZAK51 PAFC 270047
CWFAER

Coastal Waters Forecast
National Weather Service Anchorage Alaska
347 PM AKST Mon Feb 26 2018

Coastal Waters Forecast for the Northern Gulf of Alaska Coast
up to 100 nm out including Kodiak Island and Cook Inlet.

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.

PKZ197-271330-
347 PM AKST Mon Feb 26 2018
.SYNOPSIS FOR THE NORTH GULF COAST+KODIAK ISLAND WATERS+
COOK INLET...

A front exits the Southeastern Gulf by Tue morning. A second front 
enters the Western Gulf and moves over Southeastern Alaska becoming 
an open trough from the North Gulf Coast into Southeastern Alaska 
through Wed afternoon. 

$$

PKZ119-271330-
Cape Suckling to Cape Cleare-
347 PM AKST Mon Feb 26 2018

...GALE WARNING THROUGH TUESDAY...

.TONIGHT...W wind 45 kt except 25 kt near the coast. Seas 24 ft.
.TUE...W wind 40 kt diminishing to 30 kt in the afternoon. Seas
22 ft subsiding to 16 ft in the afternoon.
.TUE NIGHT...NW wind 30 kt. Seas 10 ft. Freezing spray.
.WED AND WED NIGHT...N wind 35 kt. Seas 11 ft.
.THU...N wind 25 kt. Seas 7 ft.
.FRI THROUGH SAT...Variable wind 10 kt. Seas 4 ft.

$$

PKZ120-271330-
Cape Cleare to Gore Point-
347 PM AKST Mon Feb 26 2018

...STORM WARNING TONIGHT...

.TONIGHT...W wind 50 kt except 30 kt near the coast. Seas 23 ft.
.TUE...W wind 45 kt becoming NW 25 kt in the afternoon. Seas 17 ft
subsiding to 9 ft in the afternoon. Freezing spray.
.TUE NIGHT...NW wind 35 kt. Seas 9 ft. Freezing spray.
.WED...N wind 30 kt. Seas 9 ft.
.WED NIGHT...N wind 20 kt. Seas 7 ft.
.THU...N wind 15 kt. Seas 6 ft.
.FRI...Variable wind 10 kt. Seas 5 ft.
.SAT...Variable wind 10 kt. Seas 5 ft.

$$

PKZ121-271330-
Resurrection Bay-
347 PM AKST Mon Feb 26 2018

...GALE WARNING TUESDAY NIGHT...

.TONIGHT...N wind increasing to 25 kt. Seas building to 5 ft. 
Freezing spray.
.TUE...N wind 25 kt. Seas 5 ft. Freezing spray.
.TUE NIGHT...N wind 35 kt. Seas 7 ft. Freezing spray.
.WED...N wind 35 kt. Seas 7 ft.
.WED NIGHT...N wind 30 kt. Seas 6 ft.
.THU...N wind 25 kt. Seas 5 ft.
.FRI...N wind 20 kt. Seas 4 ft.
.SAT...N wind 15 kt. Seas 3 ft.

$$

PKZ125-271330-
Prince William Sound-
347 PM AKST Mon Feb 26 2018

...GALE WARNING THROUGH TUESDAY...

.TONIGHT...NW wind 35 kt except 20 kt east of Seal Island. Seas 4 ft
building to 7 ft after midnight. Freezing spray.
.TUE...NW wind 35 kt diminishing to 25 kt in the afternoon. Seas
7 ft subsiding to 4 ft in the afternoon. Freezing spray.
.TUE NIGHT...NW wind 30 kt. Seas 6 ft. Freezing spray.
.WED...N wind 25 kt. Seas 6 ft.
.WED NIGHT...N wind 20 kt. Seas 4 ft.
.THU...N wind 20 kt. Seas 3 ft.
.FRI THROUGH SAT...NE wind 10 kt. Seas 2 ft.

$$

PKZ126-271330-
Port Valdez-
347 PM AKST Mon Feb 26 2018

...SMALL CRAFT ADVISORY TUESDAY NIGHT...

.TONIGHT...Variable wind less than 10 kt becoming NE 15 kt after
midnight. Seas 3 ft. Freezing spray.
.TUE...NE wind 15 kt diminishing to 10 kt in the afternoon. Seas
3 ft. Freezing spray.
.TUE NIGHT...NE wind 15 kt increasing to 25 kt after midnight.
Seas 3 ft building to 5 ft after midnight. Freezing spray.
.WED AND WED NIGHT...NE wind 25 kt. Seas 5 ft.
.THU...NE wind 20 kt. Seas 4 ft.
.FRI THROUGH SAT...NE wind 10 kt. Seas 2 ft.

$$

PKZ127-271330-
Valdez Narrows-
347 PM AKST Mon Feb 26 2018

...GALE WARNING TUESDAY NIGHT...

.TONIGHT...NE wind 15 kt increasing to 25 kt after midnight. Seas
3 ft. Freezing spray.
.TUE...N wind 25 kt. Seas 3 ft. Freezing spray.
.TUE NIGHT...N wind 25 kt becoming NE 35 kt after midnight. Seas
4 ft. Freezing spray.
.WED...N wind 35 kt. Seas 4 ft.
.WED NIGHT...N wind 30 kt. Seas 3 ft.
.THU...NE wind 30 kt. Seas 3 ft.
.FRI THROUGH SAT...NE wind 10 kt. Seas 2 ft.

$$

PKZ128-271330-
Valdez Arm-
347 PM AKST Mon Feb 26 2018

...SMALL CRAFT ADVISORY TUESDAY NIGHT...

.TONIGHT...NE wind 10 kt increasing to 15 kt after midnight. Seas
3 ft.
.TUE...N wind 20 kt. Seas 3 ft. Freezing spray.
.TUE NIGHT...N wind 20 kt becoming NE 30 kt after midnight. Seas
6 ft. Freezing spray.
.WED...N wind 35 kt. Seas 7 ft.
.WED NIGHT...N wind 20 kt. Seas 4 ft.
.THU...NE wind 20 kt. Seas 4 ft.
.FRI THROUGH SAT...NE wind 10 kt. Seas 2 ft.

$$

PKZ129-271330-
Passage Canal-
347 PM AKST Mon Feb 26 2018

...SMALL CRAFT ADVISORY THROUGH TUESDAY NIGHT...

.TONIGHT...W wind 20 kt increasing to 30 kt after midnight. Gusts to
50 kt near Whittier after midnight. Seas 3 ft building to 5 ft after
midnight. Freezing spray.
.TUE...W wind 30 kt diminishing to 15 kt in the afternoon. Gusts to
50 kt near Whittier in the morning. Seas 5 ft subsiding to 2 ft in 
the afternoon. Freezing spray.
.TUE NIGHT...W wind 25 kt. Seas 4 ft. Freezing spray.
.WED...W wind 25 kt. Seas 4 ft.
.WED NIGHT...W wind 20 kt. Seas 3 ft.
.THU...W wind 15 kt. Seas 2 ft.
.FRI THROUGH SAT...E wind 15 kt. Seas 2 ft.

$$

PKZ130-271330-
West of Barren Islands including Kamishak Bay-
347 PM AKST Mon Feb 26 2018

...STORM WARNING TONIGHT AND TUESDAY NIGHT...
...HEAVY FREEZING SPRAY WARNING TUESDAY NIGHT...

.TONIGHT...W wind 50 kt diminishing to 40 kt after midnight. Seas
16 ft subsiding to 10 ft after midnight. Freezing spray.
.TUE...W wind 20 kt becoming NW 30 kt in the afternoon. Seas 4 ft
building to 8 ft in the afternoon. Freezing spray.
.TUE NIGHT...NW wind 50 kt. Seas 12 ft. Heavy freezing spray.
.WED...NW wind 45 kt. Seas 10 ft.
.WED NIGHT...NW wind 25 kt. Seas 5 ft.
.THU...N wind 25 kt. Seas 5 ft.
.FRI...N wind 15 kt. Seas 3 ft.
.SAT...NW wind 20 kt. Seas 4 ft.

$$

PKZ131-271330-
Barren Islands East-
347 PM AKST Mon Feb 26 2018

...STORM WARNING TONIGHT...

.TONIGHT...W wind 50 kt. Seas 21 ft. Freezing spray.
.TUE...W wind 35 kt. Seas 13 ft. Freezing spray.
.TUE NIGHT...NW wind 45 kt. Seas 14 ft. Freezing spray.
.WED...NW wind 40 kt. Seas 13 ft.
.WED NIGHT...NW wind 35 kt. Seas 9 ft.
.THU...N wind 25 kt. Seas 7 ft.
.FRI...Variable wind 10 kt. Seas 5 ft.
.SAT...NW wind 20 kt. Seas 6 ft.

$$

PKZ132-271330-
Marmot Island to Sitkinak-
347 PM AKST Mon Feb 26 2018

...STORM WARNING TONIGHT...

.TONIGHT...W wind 50 kt diminishing to 35 kt after midnight. Seas
22 ft. Snow showers.
.TUE...W wind 30 kt becoming NW 40 kt in the afternoon. Seas 13
ft. Snow showers.
.TUE NIGHT...NW wind 40 kt. Seas 13 ft.
.WED...NW wind 40 kt. Seas 13 ft.
.WED NIGHT...NW wind 35 kt. Seas 10 ft.
.THU...NW wind 20 kt. Seas 8 ft.
.FRI...SE wind 15 kt. Seas 7 ft.
.SAT...N wind 15 kt. Seas 8 ft.

$$

PKZ136-271330-
Chiniak Bay-
347 PM AKST Mon Feb 26 2018

...GALE WARNING TONIGHT...

.TONIGHT...W wind 45 kt diminishing to 25 kt after midnight. Seas
8 ft subsiding to 4 ft after midnight. Freezing spray. Snow
showers.
.TUE...SW wind 10 kt becoming N 20 kt in the afternoon. Seas 3 ft.
.TUE NIGHT...NW wind 30 kt. Seas 4 ft. Freezing spray.
.WED...NW wind 30 kt. Seas 4 ft.
.WED NIGHT...NW wind 20 kt. Seas 3 ft.
.THU...NW wind 15 kt. Seas 2 ft.
.FRI...Variable wind less than 10 kt. Seas 3 ft.
.SAT...NW wind 10 kt. Seas 2 ft.

$$

PKZ137-271330-
Marmot Bay-
347 PM AKST Mon Feb 26 2018

...GALE WARNING TONIGHT...

.TONIGHT...W wind 45 kt diminishing to 30 kt after midnight. Seas
9 ft. Freezing spray. Snow showers.
.TUE...SW wind 10 kt becoming NW 20 kt in the afternoon. Seas 2
ft.
.TUE NIGHT...NW wind 30 kt. Seas 5 ft. Freezing spray.
.WED...NW wind 25 kt. Seas 4 ft.
.WED NIGHT...NW wind 20 kt. Seas 3 ft.
.THU...NW wind 15 kt. Seas 2 ft.
.FRI...Variable wind less than 10 kt. Seas 3 ft.
.SAT...NW wind 10 kt. Seas 2 ft.

$$

PKZ138-271330-
Shelikof Strait-
347 PM AKST Mon Feb 26 2018

...GALE WARNING TONIGHT...

.TONIGHT...W wind 45 kt becoming SW 30 kt after midnight. Seas
15 ft. Freezing spray.
.TUE...W wind 15 kt becoming NW 30 kt in the afternoon. Seas 4 ft
building to 7 ft in the afternoon.
.TUE NIGHT...NW wind 30 kt. Seas 7 ft. Freezing spray.
.WED...NW wind 25 kt. Seas 5 ft.
.WED NIGHT...N wind 15 kt. Seas 3 ft.
.THU THROUGH FRI...NE wind 15 kt. Seas 3 ft.
.SAT...NW wind 15 kt. Seas 3 ft.

$$

PKZ139-271330-
Cook Inlet Kalgin Island to Point Bede-
347 PM AKST Mon Feb 26 2018

...GALE WARNING TONIGHT...

.TONIGHT...W wind 45 kt diminishing to 35 kt after midnight. Seas
in ice free waters 11 ft. Freezing spray.
.TUE...NW wind 20 kt. Seas in ice free waters 5 ft subsiding to 3
ft in the afternoon. Freezing spray.
.TUE NIGHT...NW wind 25 kt. Seas in ice free waters 5 ft. Freezing
spray.
.WED AND WED NIGHT...N wind 20 kt. Seas in ice free waters 5 ft.
.THU...NE wind 20 kt. Seas in ice free waters 5 ft.
.FRI...NE wind 15 kt. Seas in ice free waters 3 ft.
.SAT...N wind 10 kt. Seas in ice free waters 3 ft.

$$

PKZ140-271330-
Cook Inlet North of Kalgin Island-
347 PM AKST Mon Feb 26 2018

.TONIGHT...W wind 15 kt.
.TUE...Variable wind less than 10 kt.
.TUE NIGHT...Variable wind less than 10 kt becoming NE 10 kt after
midnight.
.WED...Variable wind less than 10 kt.
.WED NIGHT...N wind 10 kt.
.THU...N wind 15 kt.
.FRI THROUGH SAT...N wind 10 kt.

$$

PKZ141-271330-
Kachemak Bay-
347 PM AKST Mon Feb 26 2018

...GALE WARNING TONIGHT...

.TONIGHT...W wind 40 kt. Seas 15 ft. 
.TUE...NW wind 20 kt. Seas 6 ft subsiding to 2 ft in the
afternoon. Freezing spray.
.TUE NIGHT...NW wind 25 kt. Seas 3 ft. Freezing spray.
.WED AND WED NIGHT...N wind 20 kt. Seas 2 ft.
.THU...N wind 20 kt. Seas 2 ft.
.FRI...NE wind 10 kt. Seas 2 ft.
.SAT...N wind 10 kt. Seas 2 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
403 PM AKST Sun Feb 25 2018

.ANALYSIS AND UPPER LEVELS...
A large vertically stacked low is tracking northeastward across
the central Bering Sea with a frontal system way out ahead of it
approaching Southwest Alaska. A strong low level jet on the south
side of the low in an area of cold air advection and instability
is leading to storm force winds along the western Aleutians and
on up into the southern Bering Sea. Shemya reported consistent
gusts to around 60 kt this morning, so there may be a few
hurricane force gusts across the aforementioned marine areas. A
strong upper level jet streak on the front side of the upper
trough is what is helping to drive the low level frontal system
eastward. Snow is quickly spreading onshore in Southwest Alaska,
with severely reduced visibilities along the Kuskokwim Delta coast
where winds ahead of the front are strongest. A Winter Weather
Advisory for blowing snow remains in effect for this area until
7pm Sunday evening.

Further east, Southcentral Alaska is under the influence of high
pressure today. Areas of fog and stratus expanded this morning
over northern Cook Inlet, Anchorage, and portions of the Susitna
Valley as a shallow surface inversion steepened. The sun is
helping to erode this as the day wears on. Weak cold advection
and tight pressure gradients behind the last system continue to
produce localed gap winds along the north Gulf coast, though they
are trending downward.

&&

.MODEL DISCUSSION...
Models remain in good agreement and overall forecast confidence
remains high. There will be some forecast challenges Monday night
through Tuesday with determining timing and impact from a series
of upper level short-waves which drop southward across western
Alaska then move across Southcentral. This has potential to
prolong snowfall, particularly on the west slopes of mountain
ranges (with persistent strong upslope flow), and result in
locally higher snowfall amounts (most notably for the west side
of the Chugach and Talkeetna Mountains including the Anchorage
Hillside). One other forecast challenge will be determining how
strong to go with winds across Southwest Alaska and into the
western Gulf as polar air advects southward on Monday. The
environment will be favorable for strong erratic gusts to mix down
to the surface, so winds could be quite variable from one
location to the next.

&&

.AVIATION...
PANC...Fog has moved out of the terminal, but is still sitting
over northern Cook Inlet. As southerly low level flow moves up
the Inlet early this evening the fog could briefly move back in
before the strengthening winds and arrival of clouds bring an end
to the fog altogether. Will monitor latest trends closely and
adjust TAF accordingly.

For the the next system, deep southwest flow will lead to another
round of snow. While MVFR conditions are expected to prevail
during the period of snow, there could be a short duration of IFR
during the heaviest snow, most likely around 12z. After the first
upper level short-wave moves through early Monday, the mean low
to mid level flow will become a bit more westerly. From here on
out would expect the heaviest snow and lowest ceiling/vis to be
over east Anchorage and the front range of the Chugach. The
terminal will be on the western edge of snow (and MVFR
conditions), with VFR conditions likely prevailing over northern
Cook Inlet just to the west of the terminal. This will remain the
case for a good portion of Monday and Monday night. It's
challenging to determine what the prevailing conditions will be,
but would expect a mix of MVFR snow and some periods of low end
VFR conditions in between upper waves.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
Brief high pressure and outflow winds will quickly give way to
increasing clouds and eventually snow as the next low moves into
the North Gulf of Alaska tonight. This will bring a widespread but
quick hitting shot of snow tonight and early Monday morning. With
deep layer southwest flow and a dendritic zone solidly in that
southwest flow regime, it is expected that snow ratios should be
rather high with fluffy, rapidly accumulating snow likely.
Thereafter, by Monday afternoon, the snow event will shift to an
orographic lift "event" with snow favoring the west facing slopes
of the Chugach, Talkeetna, and Wrangell Mountains. The heaviest
snow accumulations will be across east Anchorage and the Hillside,
Eagle River, and up into the Matanuska Valley where 5-8+ inches
of snow is possible. Snow now looks likely to linger through
Monday night into Tuesday morning across those areas, otherwise,
there is little change in forecasting thinking from yesterday.

Meanwhile, as the low shifts east and strong northwest flow aloft
increases (along with increasing cold air advection), gap winds
will rapidly increase, especially through gaps which favor
westerly flow (the Barren Islands, Passage Canal and Whittier,
Kodiak City, and even Kachemak Bay). Storm force winds will
channel through the Barrens with gusts to 50-65 MPH through Kodiak
City. Snow showers will likely linger longer near Kachemak Bay,
and some blowing snow is possible, specifically over the Homer
Bluff. Expect some blowing snow along the Anchorage Hillside, as
well, Monday night and Tuesday as strong northerly winds increase.
Snow tapers off and ends Tuesday while strong offshore flow
continues.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
A frontal system currently pushing into the southwest coast will
bring another round of snow and gusty winds to most locations,
with 2-5" accumulating by Monday afternoon. Over a foot of snow
is expected for some upslope locations on the western side of the
Kuskokwim and Alaska Ranges as strong westerly flow will help
promote good orographic lifting. Some warmer air intruding over
the AKPen will keep the overall precipitation type as a mix of
rain and snow through this evening, with snow being the
predominant precipitation type from King Salmon northward. Later
tonight colder air will filter back in from the west along the
southern periphery of the low, changing much of the mixed
precipitation back to snow.

Colder air will continue to move in behind the front causing
temperatures to fall throughout the day on Monday, with high
temps expected in the early morning. The cold air advection will
also lead to strong west/northwesterly winds Sunday night into
Monday across Bristol Bay and into the lower Kuskokwim River
Valley. Winds could gust as high as 50-60 mph along the Bristol
Bay coast with even higher gusts possible through channeled
terrain over the AKPEN. Because of the strong northwest flow, snow
showers will continue in the mountains through much of the day,
potentially continuing through much of Monday night.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
An upper level trough over the central Bering sea has forced a
transient upper level ridge eastward over the southwest Mainland,
continuing the progressive pattern seen across the area this
week. The associated frontal system is currently pushing inland
from the eastern Bering, leaving some strong gusty winds and
showery condition in its wake. A 140 kt jet max on the bottom of
the upper level trough will support the development of this
system, bringing a swath of storm force surface winds (50 kt) and
building seas to the Bering Sea between the Aleutians and
Pribilofs this evening through Monday morning. The long fetch of
the westerly winds will build seas up to 40 ft by tonight, with
the core of the strong winds and higher seas clipping Saint George
Island overnight tonight.

Once the low moves into Southwest Alaska, conditions will calm
down somewhat, with a much weaker low moving into the western
Aleutians late tonight into Monday morning. This weak low will
slowly track eastward through the central Bering through Monday
night, but no hazardous weather is expected from it. The next
system approaches the Western Aleutians and Bering from the north
Pacific Tuesday afternoon, bringing another round of wet and windy
conditions to the area.

&&

.LONG TERM FORECAST (Days 3 through 7)...
The GFS has maintained decent run to run continuity with the major
synoptic features. At the onset of this forecast period, the
latest iteration of the GFS ensembles has a tight clustering with
the low over the Western Bering, the high over the Yukon/NW
Territories, and the low over SE AK. There is a third low that all
of the global models are hinting at coming into the North Pacific
but there has been too much variance even with the more stable
model guidance. Any way you slice it, a progressive and amplified
pattern is on tap most of this period. The primary sensible
weather highlight to look for this package will be the storm force
and potentially hurricane force winds over the Western and
Central Bering as the low passes by Shemya and the surface
pressure possibly drops below 950 mb Wednesday. The GFS and the
ECMWF really bring that deepening trough with multiple shortwaves
across the Bering and into Western Alaska through Day 6.
Confidence is building that this unsettled pattern will
materialize.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...Winter Weather Advisory 101 111 155.
MARINE...Storm Warning 120 130>132 138 160 165 175 179.
 Gale Warning 119 136 137 139 141 150 155 170>174 176>178 180
185.
 Heavy Freezing Spray 121 130.

&&

SYNOPSIS AND MODEL DISCUSSION...SB
SOUTHCENTRAL ALASKA...JA
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...PEPE
LONG TERM...PJS