Gale Warning 258, NWS Anchorage, AK

839 
FZAK62 PAFC 141159
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
359 AM AKDT FRI APR 14 2017

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.

PKZ499-150115-
359 AM AKDT FRI APR 14 2017
.SYNOPSIS FOR CENTRAL BERING SEA...

A 978 MB LOW AT 52N 164E MOVES TO 58N 175E AT 1003 MB BY SUN
MORNING. THE ASSOCIATED FRONT PUSHES INTO THE SOUTHERN ALASKA 
PENINSULA BY SUN MORNING. A 1003 MB LOW FORMS NEAR 53N 167W SAT 
MORNING AND MOVES TO 54N 164W BY SUN MORNING. A 1006 MB LOW FORMS 
AROUND 50N 175W SUN MORNING.

$$

PKZ411-150115-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE-
359 AM AKDT FRI APR 14 2017

.TODAY...S TO W WIND 10 TO 20 KT. SEAS 9 TO 14 FT.
.TONIGHT...S WIND 10 TO 25 KT. SEAS 11 TO 16 FT.
.SAT...S WIND 15 TO 25 KT. SEAS 11 TO 16 FT.
.SAT NIGHT...SW WIND UP TO 15 KT. SEAS 8 TO 12 FT.
.SUN...W WIND UP TO 15 KT. SEAS 5 TO 8 FT.
.MON THROUGH TUE...NE WIND UP TO 15 KT. SEAS 4 TO 7 FT.

$$

PKZ412-150115-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N-
359 AM AKDT FRI APR 14 2017

.TODAY...SE TO SW WIND 15 TO 30 KT. SEAS 9 TO 14 FT. RAIN.
.TONIGHT...SE TO SW WIND 15 TO 30 KT. SEAS 10 TO 13 FT.
.SAT...S WIND 10 TO 15 KT. SEAS 8 TO 12 FT.
.SAT NIGHT...S WIND UP TO 15 KT. SEAS 8 TO 12 FT.
.SUN...N WIND UP TO 15 KT. SEAS 5 TO 9 FT.
.MON THROUGH TUE...NE WIND UP TO 20 KT. SEAS 6 FT.

$$

PKZ413-150115-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N-
359 AM AKDT FRI APR 14 2017

...GALE WARNING TODAY...

.TODAY...SE TO SW WIND 20 TO 35 KT. SEAS 8 TO 13 FT. RAIN.
.TONIGHT...SW WIND 10 TO 20 KT. SEAS 8 TO 11 FT.
.SAT...SW WIND 10 TO 15 KT. SEAS 8 TO 12 FT.
.SAT NIGHT...SW WIND UP TO 15 KT. SEAS 7 TO 11 FT.
.SUN...NW WIND UP TO 20 KT. SEAS 5 TO 8 FT.
.MON THROUGH TUE...NE WIND UP TO 20 KT. SEAS 4 TO 7 FT.

$$

PKZ414-150115-
BERING SEA OFFSHORE EAST OF 171W-
359 AM AKDT FRI APR 14 2017

.TODAY...SE WIND 15 TO 30 KT. SEAS IN ICE FREE WATERS 3 TO 8 FT.
RAIN.
.TONIGHT...SE WIND 15 TO 30 KT. SEAS IN ICE FREE WATERS 3 TO 8 FT.
RAIN.
.SAT...SE WIND 15 KT. SEAS IN ICE FREE WATERS 3 TO 7 FT. RAIN.
.SAT NIGHT...E WIND 10 TO 20 KT. SEAS IN ICE FREE WATERS 3 TO 7
FT.
.SUN THROUGH TUE...NE WIND 10 TO 20 KT. SEAS IN ICE FREE WATERS 3
TO 6 FT.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
444 AM AKDT Thu Apr 13 2017

.ANALYSIS AND UPPER LEVELS...
A strong ridge over mainland AK continues to dominate the pattern
while a trough remains over the Bering. The jet moves into our
picture from west to east at about 95 kts near the Western
Aleutians. It then dives down into the North Pacific at about 80
kts in support of the Bering trough. It then quickly climbs back
north to go up and over the ridge between 85-125 kts before
exiting the mainland near Valdez. This pattern is allowing some weak
fronts to attempt to bring some light precipitation into
Southwest AK. Trouble is, as they run into the dry air under the
ridge, they just fall apart. Over Southcentral, this dry air is
bringing clear skies making for cool nights and warm days under
the April sun. The synoptic offshore gradient is making for some
gusty winds in the typical gap locations (Thompson Pass, Copper
River Basin, Valdez, etc). Way out over the Western Bering, a few
passing lows continue to bring rain and some gale-force winds to
the Aleutians.

&&

.MODEL DISCUSSION...
Model guidance remains in excellent agreement and forecast
confidence is high through early in the weekend. The higher
resolution named was leaned upon for this forecast package.

&&

.AVIATION...
PANC...VFR conditions will persist. There should be a slight
uptick in northerly winds this evening as a shortwave drops in to
our east. However, this feature has looked less and less
impressive since yesterday.

&&

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

The current pattern of warm and sunny days and cool clear nights
should persist into the weekend over Southcentral Alaska. Some
gusty winds through channeled terrain will be around today but
begin to diminish overnight tonight.
The only chance for any precipitation remains over the northern
part of the Wrangell Mountains and that very eastern section of
the Alaska Range through tonight.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
High pressure will continue to keep the bulk of the Southwest
mainland warm, sunny, and dry through the end of the work week as
the upper level ridge closes off over the western interior. The
decaying front sitting just offshore of the Kuskokwim Delta will
keep cloud cover and a chance for some light rain along the
immediate coast through this afternoon. Weak onshore flow ahead of
the next front to traverse the Bering will increase fog potential
along the coast beginning late tonight. However, confidence in
this scenario remains on the low side given the lack of fog
development with a similar setup over the past few days.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
The pattern will remain somewhat active across the Bering in the
short term as one front continues to weaken in place today over
the eastern Bering while the next system tracks across the
western and central Bering accompanied by another round of rain
(possibly mixed with snow at times) and gusty southerly winds.
This next front will undergo a similar evolution to the current
feature as it moves to the eastern Bering on Friday, then stalls
out and gradually dissipates as it encounters the stout ridge over
the western mainland. Meanwhile, the parent low will slowly push
into the Bering from Kamchatka and keep showery conditions over
the western Bering heading into the weekend.

&&

.LONG TERM FORECAST (Days 3 through 7)...
The biggest question mark moving through the weekend is with a
trough that is tracking south through mainland Alaska. Previous
model runs had a split decision on what to do with this feature.
The EC and GEM stalled it over the central part of the state
keeping the coldest air north of the Alaska Range. The GFS pushed
the trough through Southcentral Alaska bringing down the colder
air. Today there is some agreement that the trough will elongate
over the central part of the state and some of the energy will
break off and move west. The biggest differences are what happen
with the easterly portion. The GEM stalls it out while the GFS and
EC push a weaker wave through Southcentral Alaska.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...None.
MARINE...Gale Warning 173-178.

&&

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