Gale Warning 391, NWS Anchorage, AK

658 
FZAK62 PAFC 302301
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
301 PM AKDT MON MAY 30 2016

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.

PKZ499-311330-
301 PM AKDT MON MAY 30 2016
.SYNOPSIS FOR CENTRAL BERING SEA...
A 986 MB LOW NEAR 52N 170W MOVES TO 53N 171W AT 987 MB TUE
AFTERNOON...THEN MOVES TO 52N 169W AT 995 MB WED AFTERNOON. A 1006
MB LOW NEAR 61N 165W RACES WESTWARD TO NEAR THE KAMCHATKA
PENINSULA AS A LOW PRESSURE TROUGH BY TUE MORNING.

$$

PKZ411-311330-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE-
301 PM AKDT MON MAY 30 2016

.TONIGHT...NE WIND 10 TO 20 KT. SEAS 6 TO 9 FT.
.TUE...N WIND 15 KT BECOMING 10 TO 25 KT IN THE AFTERNOON. SEAS 5
TO 8 FT.
.TUE NIGHT...NE WIND 10 TO 25 KT. SEAS 6 TO 11 FT. PATCHY FOG.
.WED...N WIND 10 TO 20 KT. SEAS 6 TO 11 FT.
.WED NIGHT...N WIND 10 TO 20 KT. SEAS 8 FT.
.THU THROUGH SAT...NE WIND 10 TO 20 KT. SEAS 4 TO 7 FT.

$$

PKZ412-311330-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N-
301 PM AKDT MON MAY 30 2016

...GALE WARNING TUESDAY...

.TONIGHT...NE WIND 15 TO 30 KT. SEAS 5 TO 9 FT.
.TUE...NE WIND 25 TO 40 KT. SEAS 8 TO 16 FT.
.TUE NIGHT...NE WIND 30 KT. SEAS 11 TO 15 FT.
.WED...NE WIND 25 KT. SEAS 8 TO 12 FT.
.WED NIGHT...N WIND 20 KT. SEAS 6 TO 9 FT.
.THU THROUGH SAT...NE WIND 20 KT. SEAS 4 TO 7 FT.

$$

PKZ413-311330-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N-
301 PM AKDT MON MAY 30 2016

...GALE WARNING TONIGHT...

.TONIGHT...NE WIND 20 TO 35 KT. SEAS 9 TO 13 FT. RAIN.
.TUE...N WIND 15 TO 30 KT. SEAS 8 TO 13 FT. RAIN.
.TUE NIGHT...NE WIND 15 TO 25 KT. SEAS 8 TO 12 FT. RAIN.
.WED...NE WIND 15 TO 25 KT. SEAS 8 TO 11 FT.
.WED NIGHT...N WIND 20 KT. SEAS 6 TO 9 FT.
.THU THROUGH SAT...N WIND 10 TO 20 KT. SEAS 5 TO 8 FT.

$$

PKZ414-311330-
BERING SEA OFFSHORE EAST OF 171W-
301 PM AKDT MON MAY 30 2016

...GALE WARNING THROUGH TUESDAY...

.TONIGHT...E WIND 15 TO 30 KT INCREASING TO 25 TO 40 KT AFTER
MIDNIGHT. SEAS 6 TO 11 FT.
.TUE...E WIND 30 TO 40 KT. SEAS 11 TO 17 FT. RAIN.
.TUE NIGHT...NE WIND 15 TO 30 KT. SEAS 8 TO 13 FT. RAIN.
.WED...NE WIND 10 TO 25 KT. SEAS 5 TO 9 FT.
.WED NIGHT...N WIND 15 KT. SEAS 3 TO 6 FT.
.THU THROUGH FRI...N WIND UP TO 20 KT. SEAS 3 TO 7 FT.
.SAT...NE WIND UP TO 15 KT. SEAS 4 FT.

$$

501 
FZAK62 PAFC 311137
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
337 AM AKDT TUE MAY 31 2016

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.

PKZ499-010215-
337 AM AKDT TUE MAY 31 2016
.SYNOPSIS FOR CENTRAL BERING SEA...
A 982 MB LOW NEAR 53N 170W REMAINS NEARLY STATIONARY THROUGH TUE
NIGHT WHILE WEAKENING TO 991 MB...THEN MOVES INTO THE NORTH
PACIFIC NEAR 49N 167W THROUGH WED NIGHT WHILE WEAKENING TO 997 MB.

$$

PKZ411-010215-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE-
337 AM AKDT TUE MAY 31 2016

.TODAY...N WIND 15 KT BECOMING UP TO 20 KT IN THE AFTERNOON. SEAS
7 FT.
.TONIGHT...N WIND 10 TO 25 KT. SEAS 5 TO 10 FT. PATCHY FOG.
.WED...N WIND 10 TO 20 KT. SEAS 5 TO 10 FT. PATCHY FOG.
.WED NIGHT...N WIND 10 TO 20 KT. SEAS 8 FT.
.THU THROUGH SAT...NE WIND 10 TO 20 KT. SEAS 4 TO 7 FT.

$$

PKZ412-010215-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N-
337 AM AKDT TUE MAY 31 2016

...GALE WARNING TODAY...

.TODAY...NE WIND 20 TO 35 KT. SEAS 8 TO 13 FT.
.TONIGHT...NE WIND 30 KT. SEAS 9 TO 14 FT.
.WED...N WIND 25 KT. SEAS 8 TO 11 FT. PATCHY FOG.
.WED NIGHT...N WIND 25 KT. SEAS 7 FT.
.THU THROUGH SAT...NE WIND 20 KT. SEAS 6 FT.

$$

PKZ413-010215-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N-
337 AM AKDT TUE MAY 31 2016

.TODAY...N WIND 15 TO 30 KT. SEAS 7 TO 12 FT. RAIN.
.TONIGHT...NE WIND 15 TO 25 KT. SEAS 7 TO 12 FT. RAIN.
.WED...N WIND 25 KT. SEAS 9 FT. RAIN.
.WED NIGHT...N WIND 25 KT. SEAS 8 FT.
.THU THROUGH SAT...N WIND 10 TO 20 KT. SEAS 6 FT.

$$

PKZ414-010215-
BERING SEA OFFSHORE EAST OF 171W-
337 AM AKDT TUE MAY 31 2016

...GALE WARNING TODAY...

.TODAY...E WIND 25 TO 40 KT. SEAS 10 TO 16 FT. RAIN.
.TONIGHT...NE WIND 15 TO 30 KT. SEAS 7 TO 12 FT.
.WED...NE WIND 20 KT. SEAS 4 TO 8 FT.
.WED NIGHT...N WIND 20 KT. SEAS 5 FT.
.THU THROUGH FRI...N WIND UP TO 20 KT. SEAS 3 TO 8 FT.
.SAT...NE WIND UP TO 15 KT. SEAS 4 FT.

$$

121 
FZAK62 PAFC 312312
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
312 PM AKDT TUE MAY 31 2016

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.

PKZ499-011300-
312 PM AKDT TUE MAY 31 2016
.SYNOPSIS FOR CENTRAL BERING SEA...

A 986 MB LOW NEAR 53N 171W MOVES TO 52N 168W AT 995 MB WED
AFTERNOON...THEN MOVES INTO THE NORTH PACIFIC. HIGH PRESSURE
BUILDS INTO THE WESTERN BERING THROUGH THU AFTERNOON.

$$

PKZ411-011300-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE-
312 PM AKDT TUE MAY 31 2016

.TONIGHT...NE WIND 10 TO 20 KT. SEAS 5 TO 8 FT.
.WED...N WIND 10 TO 20 KT. SEAS 5 TO 10 FT.
.WED NIGHT...NW WIND 10 TO 20 KT. SEAS 8 FT. PATCHY FOG.
.THU...NW WIND 10 TO 20 KT. SEAS 4 TO 7 FT.
.THU NIGHT...NW WIND 15 KT. SEAS 5 FT.
.FRI THROUGH SUN...NE WIND 15 KT. SEAS 5 FT.

$$

PKZ412-011300-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N-
312 PM AKDT TUE MAY 31 2016

.TONIGHT...NE WIND 30 KT. SEAS 9 TO 13 FT.
.WED...N WIND 25 KT. SEAS 8 TO 11 FT.
.WED NIGHT...N WIND 25 KT. SEAS 7 FT. PATCHY FOG.
.THU...N WIND 20 KT. SEAS 7 FT.
.THU NIGHT...N WIND 10 TO 20 KT. SEAS 4 TO 7 FT.
.FRI THROUGH SUN...NE WIND 10 TO 20 KT. SEAS 5 FT.

$$

PKZ413-011300-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N-
312 PM AKDT TUE MAY 31 2016

.TONIGHT...NE WIND 15 TO 25 KT. SEAS 7 TO 11 FT. PERIODS OF RAIN.
.WED...N WIND 20 KT. SEAS 9 FT. RAIN.
.WED NIGHT...N WIND 25 KT. SEAS 8 FT.
.THU...N WIND 20 KT. SEAS 7 FT.
.THU NIGHT...N WIND 10 TO 20 KT. SEAS 7 FT.
.FRI THROUGH SUN...NE WIND 15 KT. SEAS 5 FT.

$$

PKZ414-011300-
BERING SEA OFFSHORE EAST OF 171W-
312 PM AKDT TUE MAY 31 2016

.TONIGHT...E WIND 15 TO 30 KT. SEAS 6 TO 11 FT. RAIN.
.WED...NE WIND 10 TO 20 KT. SEAS 4 TO 7 FT.
.WED NIGHT...N WIND 10 TO 20 KT. SEAS 4 FT.
.THU...N WIND 20 KT. SEAS 5 FT.
.THU NIGHT...N WIND 20 KT. SEAS 5 TO 8 FT.
.FRI...N WIND UP TO 20 KT. SEAS 3 TO 7 FT.
.SAT THROUGH SUN...E WIND UP TO 15 KT. SEAS 3 TO 6 FT.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
451 PM AKDT SUN MAY 29 2016

.ANALYSIS AND UPPER LEVELS...
The high pressure system that has been entrenched over the
mainland for the past few days is beginning to retrograde to the
west, allowing a shift in the pattern for mainland Alaska. Broad
northerly flow on the eastern side of this high has brought dry
air and warm temperatures to the mainland over the past several
days. Today, this is being enhanced by an upper level jet streak
that will move southward over the southcentral region. As the day
continues, winds have already started mixing down with gusty
winds ramping up in the Susitna Valley. This should bring down
dry air from aloft as well. Although the RH values are already low
at the surface there is a significant dry layer just above 700 mb,
as seen on this morning's sounding from Anchorage. Mixing this dry
air down should continue dry conditions around the region.

A second feature of interest this morning is a trough moving in
from the east behind the high as it continues to retrograde. This
trough is expected to pick up what little mid level moisture is
available, and combined with the upper level instability generated
by the jet streak, lead to development of thunderstorms as the
trough moves westward. Satellite shows convective activity
already this morning and a few early lightning strikes near the
Al-Can border indicate that the instability is definitely there.

Further west the pattern continues to be dominated by the upper
level high. An upper level low just south of the Aleutians will
bring precipitation to the central Aleutians today, but most of
the Bering and the west coast is currently being affected by
marine stratus, as is evident on visible satellite this morning.
As the high shifts westward, flow should be transitioning to
offshore, pushing the remaining fog in the Kuskokwim Delta out
to the Bering Sea. Once this happens, conditions will dry out
significantly.

&&

.MODEL DISCUSSION...
Model agreement was fairly high this morning and so confidence
in the short term forecast is high, except for the lingering fog
along the Kuskokwim coast, which was not handled well by any
model. The NAM was chosen for detail resolution in the short term.
By the Tuesday time frame, models begin to diverge on the
solution of the Aleutian low and confidence in the forecast
decreases.

&&

.FIRE WEATHER...
Winds and dry air mixing down from aloft and thunderstorms are the
two main fire weather concerns for today. As mentioned, winds are
already kicking up in the Susitna Valley, and the Kuskokwim Valley
is also seeing near Red Flag conditions this morning. The struggle
will be along the Kuskokwim coast where fog has taken more of a
stronghold than expected this morning. Winds are expected to
become more offshore with the upper level support in the
afternoon, but the question still remains as to whether that will
happen in time to reach Red Flag criteria this afternoon and
evening. Best chances for that occurring are in the eastern side
of the zone, where skies remained clear this morning.

As for the thunderstorms, conditions look good for the approaching
shortwave to kick off storms in the Talkeetnas and possibly down
along the Kenai as well. This wave will move westward into the
Kuskokwim Valley tomorrow, bringing widely scattered thunderstorms
to that region. For today, the layer of dry air close to the
surface brings a risk that a few thunderstorms in the Southcentral
region may be dry, although they will be isolated. As this trough
pushes westward, the upper level flow will change to be more
southerly, bringing more moisture in and lowering the risk for dry
thunderstorms in any location tomorrow.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
Thunderstorms are popping up around the area this evening, while
slightly cooler conditions are expected through midweek. Scattered
to numerous showers are blossoming mainly along the Chugach and
Copper River Basin this evening while isolated lightning strikes
are showing up as well. These conditions will hold through the
evening before tapering off overnight. On Monday most of the
shower activity will be confined to the Kenai Peninsula in the
morning. As the system that produced these showers exits, a
slightly cooler air mass will come in behind it and will bring
cooler but still above normal temperatures to the mainland with
no precipitation forecast.

A weakening jet aloft combined with a shortwave trough and modest
instability is forcing showers and thunderstorms across the area.
Most of this activity is scattered in nature except for the
leading edge of the wave, over the Kenai Mountains, which is
producing quite a few lighting strikes. This trough will sit over
the southern Kenai Monday before exiting. The air mass behind the
exiting disturbance is much more stable though small pockets of
instability will exist over the terrain.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
Ridging will continue to bring sunny and warm conditions to the
southwest mainland this evening, while a developing surface trough
will bring increasing offshore flow to the Kuskokwim River and
Delta. Over Bristol Bay, this trough will bring onshore flow to
most of the area, while weak instability will produce showers or
even a few cracks of thunder along the Alaska Range this evening.
As this onshore flow diminishes with clearing skies tonight,
patchy fog may develop for a few hours overnight for the low
lying areas of Bristol Bay.

An easterly wave will then push overhead on Monday, bringing
showers and a chance of thunderstorms to the Alaska Range for the
afternoon, which will then move westward into the Kuskokwim Valley
and Delta for the late afternoon and evening hours. Afterwards,
broad cyclonic flow aloft on Tuesday will maintain a chance of
showers for the Kuskokwim Delta and Bristol Bay, while sunny and
warm weather begins to return to the Kuskokwim Valley.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
The gale force low moving through the Aleutians will bring gusty
winds and rain to the region through Monday when it will begin to
dissipate over the Southern Bering. To the west of this low,
northerly flow and cold air advection will allow for persistent
fog/stratus that has developed over the western Bering/Aleutians
to begin to diminish.

&&

.LONG TERM FORECAST (Tuesday through Saturday)...
The pattern heading into the middle of the week shifts toward
dominating low pressure across the gulf and ridging to the west.
The Bering will trend toward a drier and more stable environment
from mid week into next weekend. Meanwhile, low pressure across
the gulf advects moisture across the southern mainland through the
end of the week bringing increased cloud cover and rain chances.
After a relatively dry Wednesday, a deformation zone sets up near
the Alaska range as another low pressure system digs toward the
eastern Beaufort sea coast on Thursday. This combined with several
upper level shortwaves moving around systems will initiate convective
diurnal showers through the weekend. Models are in good agreement
on this synoptic change, however, there are differences in handling
multiple upper level disturbances from the two dominant lows. The
NAM was used to handle the transition into Wednesday and then
switched influence in the extended forecast to ECMWF along with
some of the 06Z GEFS MEAN which provided the best consistency.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Gale Warning 155 165 170 172 173 174 175 176 177.
FIRE WEATHER...Red Flag Warning 145 153 155.

&&

SYNOPSIS AND MODEL DISCUSSION...LF
FIRE WEATHER...LF
SOUTHCENTRAL ALASKA...MTL
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...DEK
LONG TERM...KH