Gale Warning 426, NWS Anchorage, AK

630 
FZAK62 PAFC 041148
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
348 AM AKDT SAT JUN 4 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.

PKZ499-050145-
348 AM AKDT SAT JUN 4 2016
.SYNOPSIS FOR CENTRAL BERING SEA...
A WEATHER FRONT OVER THE WESTERN BERING SEA STALLS AND WEAKENS
OVER THE SOUTHWESTERN BERING TONIGHT...THEN DISSIPATES SUN NIGHT.
ANOTHER FRONT APPROACHES WESTERN ALEUTIANS SUN NIGHT. 

$$

PKZ411-050145-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE-
348 AM AKDT SAT JUN 4 2016

.TODAY...E WIND 20 TO 30 KT DIMINISHING TO 10 TO 25 KT IN THE
AFTERNOON. SEAS 6 TO 11 FT. RAIN.
.TONIGHT...E WIND 10 TO 25 KT. SEAS 6 TO 10 FT.
.SUN...E WIND 10 TO 20 KT. SEAS 7 FT.
.SUN NIGHT...E WIND 15 KT. SEAS 6 FT.
.MON THROUGH WED...N WIND 15 TO 30 KT. SEAS 4 TO 9 FT.

$$

PKZ412-050145-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N-
348 AM AKDT SAT JUN 4 2016

.TODAY...E WIND 10 TO 20 KT. SEAS 5 FT. PATCHY FOG.
.TONIGHT...NE WIND 10 TO 20 KT. SEAS 5 FT. PATCHY FOG.
.SUN...E WIND 15 KT. SEAS 5 FT.
.SUN NIGHT...E WIND UP TO 15 KT. SEAS 4 FT.
.MON THROUGH WED...NE WIND UP TO 20 KT. SEAS 3 TO 6 FT.

$$

PKZ413-050145-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N-
348 AM AKDT SAT JUN 4 2016

.TODAY...E WIND 10 TO 25 KT. SEAS 3 TO 7 FT. RAIN.
.TONIGHT...E WIND 15 KT. SEAS 3 TO 7 FT.
.SUN...E WIND 10 TO 15 KT. SEAS 4 FT.
.SUN NIGHT...E WIND 10 KT. SEAS 4 FT.
.MON THROUGH TUE...E WIND 15 TO 30 KT. SEAS 3 TO 7 FT.
.WED...N WIND 15 KT. SEAS 3 TO 6 FT.

$$

PKZ414-050145-
BERING SEA OFFSHORE EAST OF 171W-
348 AM AKDT SAT JUN 4 2016

.TODAY...NE WIND 10 TO 15 KT. SEAS 4 FT. PATCHY FOG.
.TONIGHT...E WIND 15 KT. SEAS 3 FT.
.SUN...E WIND 10 TO 15 KT. SEAS 3 FT.
.SUN NIGHT...NE WIND 10 KT. SEAS 3 FT.
.MON...NW WIND UP TO 15 KT. SEAS 3 FT.
.TUE THROUGH WED...E WIND UP TO 15 KT. SEAS 4 FT.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
445 AM AKDT FRI JUN 3 2016

.ANALYSIS AND UPPER LEVELS...

There is an arctic trough centered just north of the North Slope
with a Pacific low complex centered south of the Gulf of Alaska. A
stout closed upper high remains over Eastern Siberia. Shortwave
troughs in northerly flow along the periphery of this high, and in
association with the aforementioned arctic trough, can be seen on
satellite imagery moving across southwest Alaska and the eastern
Bering. Southern Alaska in centered in between with an upper level
COL feature in place. Over the Bering, a shortwave ridge axis is
building into the western and central Bering ahead of a
strengthening Pacific warm front.

A weak surface thermal trough exists across southwest Alaska,
centered around the Kuskokwim Mountains. This is where the
most unstable environment exists across southern Alaska with a
stronger onshore gradient across Southcentral keeping inland
instability quite a bit lower. Over the eastern Bering and far
southwest Alaska, dry northerly flow at the surface has resulted
in large swaths of clear skies which is somewhat atypical for this
time of the year.

&&

.MODEL DISCUSSION...

The numerical models are in excellent agreement with the general
synoptic pattern. There are slight differences, as usual, with the
depiction of afternoon and evening convective thunderstorms. As a
result, the higher res models were favored for both winds and
precipitation/thunderstorm patterns today and tomorrow. Forecast
confidence is high.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...
Southcentral Alaska remains in a "col" today with a low over
central Alaska and another over the Gulf. Generally isolated to
scattered showers will continue through Saturday night as the air
mass remains moist. The Susitna valley will see increased shower
activity today as the central Alaska upper low provides a little
extra moisture and dynamics. Conditions will remain unstable
enough for afternoon and evening thunderstorms over the Susitna
and Copper River basins both today and Saturday. Winds will
increase over much of the area on Saturday as surface high
pressure builds along the Gulf coast.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 and 2)...
Another round of showers and thunderstorms are on tap for the
mainland today, similar to yesterday. Expect showers to continue
through the morning for the Kuskokwim Valley, while a new round
of thunderstorms will begin to fire over the Ahklun Mountains in
the late morning. More showers and possible thunder will pop up in
the Greater Bristol Bay area as well as the Kuskokwim Mountains
and Kilbuck Mountains. All the shower activity will wane overnight
then pulse again during the afternoon on Saturday pretty much for
the whole mainland.

As for the technical details...the focus for convection today will
be the persistent low level thermal trough stretching from the
central interior through the Bristol Bay area. Instability will be
present across most of the Lower Kuskokwim Valley into Greater
Bristol Bay, however, the thermal trough will be the focus for
initiation. The trough will shift back to the north on Saturday as
the flow in the column feels the influence of an incoming trough
from the west.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 and 2)...
A frontal boundary will spread over the Western Aleutians today,
followed by the Central Aleutians overnight, and the Eastern
Aleutians by late Saturday. This front will be minimum gale force
today, but will quickly weaken below that level. The eastern
Bering Sea will stay in a drier northerly flow with stratus banked
up along the chain whereas the northern Bering Sea is clearer with
patchy areas of stratus. There is a larger bank of low stratus and
fog in the weak flow over the western Bering ahead of the
approaching front.

&&

.LONG TERM FORECAST (Days 3 through 7)...

Beginning the extended period on Sunday, there will be an active
stream of Pacific jet energy surging east toward the Panhandle of
Alaska with continued upper level troughing over northern Alaska.
The mainland pattern will begin to change as the arctic trough
over northern Alaska digs south into southwest Alaska. This will
result in increasing chances for rain across interior southwest
Alaska and across parts of the Susitna Valley. Showers and
isolated thunderstorms will remain a threat across the remainder
of Southcentral as that region remains under the influence of
weaker upper level features. This general pattern will play itself
out into midweek, with stout ridging over Eastern Siberia keeping
a drier north to east flow over a majority of the Bering Sea while
rain and showers remain over inland southern Alaska.

Midweek and beyond, the numerical global model guidance are all
strongly in agreement with the development of another large North
Pacific low developing over the Western Aleutians then moving east
into the eastern Bering. This will spread more clouds and moisture
into southern Alaska, with rain along the coast and inland
showers. This will keep temperatures seasonable with no major heat
waves or dry periods expected through next weekend.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Gale 178.
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...Ahsenmacher
SOUTHCENTRAL ALASKA...BL
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MTL
LONG TERM...Ahsenmacher

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ANCHORAGE AK
1231 PM AKDT FRI JUN 3 2016

AKZ101-111-121-145-052045-
ANCHORAGE-MATANUSKA VALLEY-WESTERN KENAI PENINSULA-SUSITNA VALLEY-
INCLUDING THE CITIES OF...ANCHORAGE...EAGLE RIVER...INDIAN...
EKLUTNA...PALMER...WASILLA...SUTTON...CHICKALOON...KENAI...
SOLDOTNA...HOMER...COOPER LANDING...TALKEETNA...WILLOW...CANTWELL
1231 PM AKDT FRI JUN 3 2016

...RISING WATER LEVELS ON AREA STREAMS AND RIVERS AS SNOW MELT
CONTINUES...

ALTHOUGH WATER IS FAIRLY HIGH AND WILL RISE A BIT MORE ON SOME
AREA STREAMS AND RIVERS THIS WEEKEND, NO FLOODING IS EXPECTED.
SIGNIFICANT RUNOFF FROM THE MELTING OF THE MOUNTAIN SNOWPACK
CONTINUES TO BE EARLIER THAN USUAL DUE TO VERY WARM SPRING
TEMPERATURES. AVAILABLE DATA SUGGESTS ABOUT HALF OF THE HEAVY
WINTER SNOWPACK IN THE KENAI MOUNTAINS HAS MELTED SINCE APRIL 1.
AN EVEN HIGHER PERCENTAGE OF TOTAL SNOWPACK LOSS HAS OCCURRED ON
THE WESTERN SIDE OF THE CHUGACH MOUNTAINS.

A GENERAL TREND TOWARD CLOUDIER AND COOLER CONDITIONS THIS WEEKEND
WILL RESULT IN A DOWNWARD TREND ON MANY RIVERS AND STREAMS BY
EARLY NEXT WEEK.

THE LATEST RIVER FORECASTS ARE ALWAYS AVAILABLE AT
WWW.WEATHER.GOV/APRFC. THIS STATEMENT WILL NOT BE UPDATED.