Gale Warning 493, NWS Anchorage, AK

832 
FZAK61 PAFC 171201
OFFAER

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
401 AM AKDT MON AUG 17 2015

OFFSHORE WATERS FORECAST FOR THE GULF OF ALASKA WEST OF 144W

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.

PKZ399-180215-
401 AM AKDT MON AUG 17 2015
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...
A 1002 MB LOW NEAR 55N 161W WILL MOVE TO 61N 146W AT 995 MB MON
NIGHT AND THEN MOVE INLAND. A TROUGH OF LOW PRESSURE WILL DEVELOP
ALONG THE NORTH GULF COAST TUE AND PERSIST THROUGH TUE NIGHT.

$$

PKZ351-180215-
GULF OF ALASKA OFFSHORE NORTH OF 57N AND WEST OF 144W-
401 AM AKDT MON AUG 17 2015

...GALE WARNING THROUGH TUESDAY...

.TODAY...S WIND 15 TO 30 KT BECOMING SW 25 TO 35 KT IN THE
AFTERNOON. SEAS 7 TO 12 FT. RAIN.
.TONIGHT...SW WIND 35 KT. SEAS 13 TO 17 FT. RAIN.
.TUE...W WIND 25 TO 35 KT. SEAS 13 TO 17 FT.
.TUE NIGHT...W WIND 20 TO 30 KT. SEAS 9 TO 16 FT.
.WED THROUGH FRI...W WIND 10 TO 25 KT. SEAS 6 TO 11 FT.

$$

PKZ352-180215-
GULF OF ALASKA OFFSHORE SOUTH OF 57N NORTH OF 55N AND WEST OF
144W-
401 AM AKDT MON AUG 17 2015

...GALE WARNING THROUGH TONIGHT...

.TODAY...SW WIND 20 TO 35 KT INCREASING TO 30 TO 40 KT IN THE
AFTERNOON. SEAS 9 TO 17 FT. RAIN.
.TONIGHT...SW WIND 25 TO 40 KT. SEAS 14 TO 18 FT. RAIN.
.TUE...W WIND 20 TO 30 KT. SEAS 11 TO 18 FT.
.TUE NIGHT...W WIND 25 KT. SEAS 8 TO 13 FT.
.WED THROUGH FRI...W WIND 10 TO 25 KT. SEAS 5 TO 10 FT.

$$

605 
FZAK61 PAFC 172338
OFFAER

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
338 PM AKDT MON AUG 17 2015

OFFSHORE WATERS FORECAST FOR THE GULF OF ALASKA WEST OF 144W

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.

PKZ399-181415-
338 PM AKDT MON AUG 17 2015
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...
A 1002 MB LOW NEAR 59N 152W WILL STRENGTHEN TO 995 MB NEAR PRINCE
WILLIAM SOUND TONIGHT BEFORE MOVING INLAND TUE MORNING. A TROUGH
OF LOW PRESSURE WILL DEVELOP ALONG THE NORTH GULF COAST TUE AND
PERSIST THROUGH WED.

$$

PKZ351-181415-
GULF OF ALASKA OFFSHORE NORTH OF 57N AND WEST OF 144W-
338 PM AKDT MON AUG 17 2015

...GALE WARNING THROUGH TUESDAY...

.TONIGHT...SW WIND 25 TO 35 KT. SEAS 13 TO 18 FT. RAIN.
.TUE...W WIND 25 TO 35 KT. SEAS 13 TO 18 FT.
.TUE NIGHT...W WIND 20 TO 30 KT. SEAS 9 TO 15 FT. PATCHY FOG.
.WED...W WIND 25 KT. SEAS 8 TO 11 FT.
.WED NIGHT...W WIND 20 KT. SEAS 6 TO 9 FT.
.THU THROUGH SAT...NW WIND 15 TO 30 KT. SEAS 5 TO 10 FT.

$$

PKZ352-181415-
GULF OF ALASKA OFFSHORE SOUTH OF 57N NORTH OF 55N AND WEST OF
144W-
338 PM AKDT MON AUG 17 2015

...GALE WARNING TONIGHT...

.TONIGHT...SW WIND 25 TO 35 KT. SEAS 15 TO 19 FT. RAIN.
.TUE...W WIND 20 TO 30 KT. SEAS 10 TO 18 FT.
.TUE NIGHT...W WIND 25 KT. SEAS 8 TO 13 FT.
.WED...W WIND 15 TO 25 KT. SEAS 6 TO 10 FT.
.WED NIGHT...W WIND 10 TO 20 KT. SEAS 5 TO 8 FT.
.THU...SW WIND 10 TO 25 KT. SEAS 4 TO 7 FT.
.FRI THROUGH SAT...NW WIND 20 TO 35 KT. SEAS 7 TO 12 FT.

$$

479 
FZAK61 PAFC 181155
OFFAER

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
355 AM AKDT TUE AUG 18 2015

OFFSHORE WATERS FORECAST FOR THE GULF OF ALASKA WEST OF 144W

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.

PKZ399-190145-
355 AM AKDT TUE AUG 18 2015
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...
A TROUGH OF LOW PRESSURE ALONG THE NORTH GULF COAST CONTINUES THROUGH
EARLY THU MORNING.

$$

PKZ351-190145-
GULF OF ALASKA OFFSHORE NORTH OF 57N AND WEST OF 144W-
355 AM AKDT TUE AUG 18 2015

...GALE WARNING TODAY...

.TODAY...W WIND 25 TO 35 KT. SEAS 12 TO 18 FT. SHOWERS.
.TONIGHT...W WIND 20 TO 30 KT. SEAS 10 TO 15 FT.
.WED...W WIND 15 TO 25 KT. SEAS 8 TO 12 FT.
.WED NIGHT...W WIND 15 TO 25 KT. SEAS 6 TO 11 FT.
.THU...SW WIND 10 TO 20 KT. SEAS 4 TO 7 FT.
.FRI THROUGH SAT...NW WIND 15 TO 30 KT. SEAS 6 TO 11 FT.

$$

PKZ352-190145-
GULF OF ALASKA OFFSHORE SOUTH OF 57N NORTH OF 55N AND WEST OF
144W-
355 AM AKDT TUE AUG 18 2015

...GALE WARNING TODAY...

.TODAY...W WIND 25 TO 35 KT DIMINISHING TO 25 KT THIS AFTERNOON.
SEAS 12 TO 18 FT. SHOWERS.
.TONIGHT...W WIND 25 KT. SEAS 8 TO 13 FT.
.WED...W WIND 20 KT. SEAS 6 TO 10 FT.
.WED NIGHT...W WIND 10 TO 20 KT. SEAS 5 TO 9 FT.
.THU...SW WIND 10 TO 25 KT. SEAS 4 TO 8 FT.
.FRI THROUGH SAT...NW WIND 20 TO 35 KT. SEAS 7 TO 12 FT.

$$

455 
FZAK61 PAFC 182356
OFFAER

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
356 PM AKDT TUE AUG 18 2015

OFFSHORE WATERS FORECAST FOR THE GULF OF ALASKA WEST OF 144W

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.

PKZ399-191400-
356 PM AKDT TUE AUG 18 2015
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A TROUGH OF LOW PRESSURE ALONG THE NORTH GULF COAST CONTINUES THROUGH
EARLY THU AFTERNOON.

$$

PKZ351-191400-
GULF OF ALASKA OFFSHORE NORTH OF 57N AND WEST OF 144W-
356 PM AKDT TUE AUG 18 2015

.TONIGHT...W WIND 20 TO 30 KT. SEAS 9 TO 14 FT.
.WED...W WIND 15 TO 25 KT. SEAS 9 FT.
.WED NIGHT...W WIND 10 TO 25 KT. SEAS 7 FT.
.THU...W WIND UP TO 15 KT. SEAS 3 TO 6 FT.
.THU NIGHT...S WIND 10 TO 20 KT. SEAS 5 FT.
.FRI THROUGH SUN...NW WIND 15 TO 30 KT. SEAS 6 TO 11 FT.

$$

PKZ352-191400-
GULF OF ALASKA OFFSHORE SOUTH OF 57N NORTH OF 55N AND WEST OF
144W-
356 PM AKDT TUE AUG 18 2015

.TONIGHT...W WIND 15 TO 25 KT. SEAS 8 TO 13 FT.
.WED...W WIND 20 KT. SEAS 8 FT.
.WED NIGHT...W WIND 10 TO 20 KT. SEAS 5 TO 8 FT.
.THU...W WIND 10 TO 20 KT. SEAS 4 TO 7 FT.
.THU NIGHT...S WIND 10 TO 25 KT. SEAS 4 TO 7 FT.
.FRI THROUGH SUN...NW WIND 15 TO 30 KT. SEAS 9 TO 14 FT.

$$

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
453 AM AKDT SUN AUG 16 2015

.ANALYSIS AND UPPER LEVELS...

A VERTICALLY STACKED LOW IS CENTERED OVER THE BERING THIS MORNING.
A SERIES OF DISTURBANCES IN THE BROAD SOUTHWEST FLOW SPIRALING
AROUND THE EAST SIDE OF THE LOW HAS CAUSED WIDESPREAD LIGHT RAIN
ACROSS SOUTHERN ALASKA TODAY WITH THE EXCEPTION OF THE COPPER
RIVER BASIN. RAINFALL TOTALS ACROSS THE ANCHORAGE BOWL CAME IN
BETWEEN ONE AND TWO TENTHS OF AN INCH. THE FIRST ROUND OF RAIN
HAS MOVED NORTH INTO THE SUSITNA VALLEY AND EAST ACROSS THE
NORTHERN GULF COAST AS SHOWN ON KENAI AND MIDDLETON ISLAND
RADARS. OVER SOUTHWEST ALASKA...THE NEXT SHORTWAVE IS BRINGING THE
SECOND ROUND OF WETTING RAINS ALONG THE KUSKOKWIM DELTA WITH THE
BETHEL RADAR FILLING IN.

IN THE UPPER LEVELS...A 120 KT JET STREAK ASSOCIATED WITH A
POSITIVELY TILTED UPPER LEVEL LOW OVER THE BERING STRETCHES FROM
THE CENTRAL ALEUTIANS TO THE KENAI PENINSULA AT THIS TIME. THE
RIGHT ENTRANCE REGION SOUTH OF THE CENTRAL ALEUTIANS IS NOW
PICKING UP THE REMNANTS OF TROPICAL STORM MOLAVE. MEANWHILE...THE
LEFT EXIT REGION AND THE DIFFLUENCE OVER SOUTHERN ALASKA IS
HELPING THE RAINFALL ACTIVITY TO BE WIDESPREAD AHEAD OF THE
SHORTWAVE TRAVELING ALONG THE JET. THE RAINFALL DIMINISHES IN THE
AREAS OF SUBSIDENCE BETWEEN THE WAVES...WHICH HAVE HELPED CREATE
THE BREAK IN THE RAINFALL NOW OVER SOUTHCENTRAL. THEREFORE...THE
FORECAST CHALLENGE IN THIS VERY UNSETTLED WEATHER PATTERN WILL BE
DETERMINING THE TIMING AND INTENSITY OF THE RAINFALL CAUSED BY THE
SHORTWAVE DISTURBANCES MOVING ALONG IN THE VERY FAST UPPER LEVEL
FLOW.

&&

.MODEL DISCUSSION...

FOR MUCH OF THE PAST WEEK THE POTENTIAL FOR THE HEAVIEST RAIN IN
SOUTHERN ALASKA WAS ASSOCIATED WITH HOW MUCH TROPICAL MOISTURE
FROM THE REMNANTS OF TROPICAL STORM MOLAVE IS CAUGHT UP WITH THE
JET STREAK NOW MOVING ACROSS SOUTHWEST ALASKA AND THE EASTERN
BERING. THAT MOISTURE NOW IS BEING TAKEN UP WITH THE LIFT
ASSOCIATED WITH THE RIGHT ENTRANCE REGION OF THE JET. THIS
MORNING...THE MODELS HAVE LARGELY SHIFTED THE CENTER OF JET BACK
TO THE NORTH COMPARED TO YESTERDAYS BROAD SOLUTION. IT IS
INTERESTING TO MONITOR HOW THE DEPICTION OF THE MOVEMENT OF THE
REMNANTS OF MOLAVE CHANGES DAY TO DAY. TWO DAYS AGO...THE MODELS
HAD MUCH MORE SPREAD AS WOULD BE EXPECTED...HOWEVER THEIR
CONSENSUS WAS TO MOVE THE REMNANTS OF MOLAVE ACROSS SOUTHCENTRAL.
YESTERDAY THEY CAME INTO MUCH BETTER AGREEMENT...THOUGH WERE MUCH
FURTHER SOUTH...KEEPING ALL ASSOCIATED PRECIPITATION SOUTH OF
KODIAK IN THE GULF. NOW THE CONSENSUS LARGELY AGREED UPON IS TO
PUT THE MOISTURE PLUME ALONG A LINE FROM THE SOUTHERN COAST OF THE
ALASKA PENINSULA ACROSS KODIAK TO THE NORTH GULF COAST BETWEEN
CORDOVA AND YAKUTAT. WHILE THERE REMAINS SOME UNCERTAINTY
REGARDING WHERE THE HEAVIEST RAIN ASSOCIATED WITH THE MOISTURE
PLUME ENDS UP...CONFIDENCE IS HIGH IN THE FORECAST FOR CONTINUED
RAINFALL.

FURTHER NORTH ACROSS SOUTHERN MAINLAND ALASKA...THE MODELS
LARGELY AGREE THAT NUMEROUS ADDITIONAL SHORTWAVES IN THE FLOW WILL
MOVE ACROSS THE AREA. THEY WILL BRING PERIODS OF RAIN OVER NEARLY
ALL OF SOUTHERN ALASKA OVER THE NEXT SEVERAL DAYS AS THE UPPER LOW
NOW OVER THE EASTERN BERING MOVES EAST INTO MAINLAND
ALASKA...INCREASING THE INSTABILITY THAT CAN TAKE ADVANTAGE OF THE
PLENTIFUL AVAILABLE MOISTURE WHEN EACH SHORTWAVE DISTURBANCE MOVES
THROUGH.

&&

.FIRE WEATHER...

A CLOUDY...MOIST AIR MASS FEATURING FREQUENT ROUNDS OF WETTING
RAIN IS NOW ENTRENCHED ACROSS ALL OF SOUTHERN ALASKA. AS
SUCH...THERE ARE NO FIRE WEATHER CONCERNS THROUGH TUESDAY. WEAK
RIDGING WILL INITIATE A DRYING TREND TUESDAY FOR SOUTHWEST ALASKA
INTO WEDNESDAY FOR SOUTHCENTRAL.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...

SOUTHWEST FLOW ALOFT WILL KEEP SOUTHCENTRAL ALASKA IN A WET
PATTERN THE NEXT FEW DAYS. THE NORTH GULF COAST INCLUDING THE
PRINCE WILLIAM SOUND AREA WILL SEE THE HEAVIEST RAINFALL AMOUNTS
THE NEXT FEW DAYS BUT THE JET STREAM WILL REMAIN OVER THE GULF AND
KEEP THE DEEPEST MOISTURE SOUTH OF THE AREA.
THE PRESSURE GRADIENT WILL INCREASE RAPIDLY ACROSS THE MARINE
AREAS MONDAY NIGHT AND USHER IN SOME GALE FORCE WINDS BY
TUESDAY.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 AND 2)...
THERE WILL BE A BRIEF BREAK IN THE RAINFALL FOR PORTIONS OF SOUTHWEST
ALASKA THIS MORNING AS A SHORTWAVE ROTATES NORTHWARD THROUGH THE
KUSKOKWIM VALLEY AND A SHOT OF DRY AIR PUSHES INTO BRISTOL BAY.
THIS DRY AIR IS VERY EVIDENT ON WATER VAPOR AND RADAR IMAGERY
THIS MORNING AND IS EXPECTED TO CONTINUE TO PUSH INTO THE MIDDLE
KUSKOKWIM VALLEY THROUGH THE EARLY AFTERNOON HOURS. RAINFALL WILL
REDEVELOP OVER THE REGION LATE THIS AFTERNOON AS A SHORTWAVE
CURRENTLY NEAR THE PRIBILOF ISLANDS AND A WAVE EMBEDDED IN THE
SOUTHWESTERLY FLOW OVER THE ALASKA PENINSULA WILL MOVE INTO THE
SOUTHWEST MAINLAND. WIDESPREAD SHOWERS WILL CONTINUE ON MONDAY AND
BEGIN TO DIMINISH MONDAY EVENING AS THE AXIS OF THE UPPER TROUGH
MOVES EASTWARD AND HIGH PRESSURE IS EXPECTED TO BRIEFLY BUILD INTO
THE SOUTHWEST MAINLAND.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 AND 2)...
HIGH PRESSURE WILL BUILD INTO THE WESTERN BERING SEA TODAY AS THE
UPPER LEVEL TROUGH AND ASSOCIATED SURFACE LOWS MOVE EASTWARD INTO
SOUTHWEST ALASKA. SOUTH OF THE EASTERN ALEUTIANS AND ALASKA
PENINSULA...A WEAK SURFACE LOW EMBEDDED IN THE TROPICAL MOISTURE
RIDING OVER THE SURFACE OF THE NORTHEAST PACIFIC HIGH WILL BRING
INCREASED WINDS AND HIGHER SEAS IN THE COASTAL MARINE AREAS SOUTH
OF THE ALASKA PENINSULA TONIGHT THROUGH TUESDAY NIGHT. ALTHOUGH
THE SURFACE LOW IS EXPECTED TO BE FAIRLY WEAK...THE TIGHT PRESSURE
GRADIENT...A LONG FETCH AND THE REASONABLY LINEAR TRACK OF THE
LOW WILL CREATE HIGHER WAVE HEIGHTS THAN WOULD NORMALLY BE
EXPECTED WITH THIS STRENGTH OF A SYSTEM. AT THIS TIME IT LOOKS
LIKE THE HIGHEST SEAS AND WINDS WILL REMAIN AT THE EDGE OF THE
FORECAST AREA...HOWEVER A MORE NORTHERLY TRACK TO THE LOW COULD
BRING GALE FORCE WINDS INTO THE MARINE AREAS.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
THE MOST WIDESPREAD RAIN WILL BEGIN TO TAPER OFF MONDAY NIGHT
INTO TUESDAY AS THE BROAD BERING SEA TROUGH PUSHES INLAND AND THEN
MOVES EAST OF THE REGION. THIS WILL YIELD A MORE SHOWERY REGIME
FOR THE REMAINDER OF THE WEEK AS A STRONG AND PERSISTENT RIDGE
OVER THE NORTHEAST PACIFIC KEEPS THE UPPER LEVEL JET FOCUSED OVER
THE SOUTHERN MAINLAND...WITH SEVERAL WAVES TRAVERSING THE MAINLAND
FROM WEST TO EAST IN FAST QUASI-ZONAL FLOW.

&&

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

&&

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