Gale Warning 472, NWS Anchorage, AK

337 
FZAK61 PAFC 282301
OFFAER

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 PM AKDT WED AUG 28 2013

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.

PKZ399-291500-
400 PM AKDT WED AUG 28 2013
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 995 MB LOW NEAR 55N 159W WILL MOVE TO 55N 152W WHILE STRENGTHENING
TO 986 MB BY THU MORNING...THEN MOVE INTO THE NORTHEASTERN PACIFIC
AND WEAKEN TO 1004 MB BY FRI AFTERNOON.

$$

PKZ351-291500-
GULF OF ALASKA OFFSHORE NORTH OF 57N AND WEST OF 144W
400 PM AKDT WED AUG 28 2013

...GALE WARNING THURSDAY...

.TONIGHT...SE WIND 20 TO 30 KT. SEAS 7 FT. RAIN.
.THU...SE WIND 25 TO 35 KT. SEAS 9 TO 14 FT. RAIN.
.THU NIGHT...E WIND 30 KT BECOMING NE 20 KT AFTER MIDNIGHT. SEAS
8 TO 13 FT. RAIN.
.FRI AND FRI NIGHT...N WIND 15 KT. SEAS 7 FT.  
.SAT THROUGH MON...S WIND 20 KT. SEAS 7 FT.  

$$

PKZ352-291500-
GULF OF ALASKA OFFSHORE SOUTH OF 57N NORTH OF 55N AND WEST OF
144W
400 PM AKDT WED AUG 28 2013

...GALE WARNING THROUGH THURSDAY NIGHT...

.TONIGHT...SE WIND 20 KT IN THE EVENING INCREASING TO 35 KT. SEAS 7
TO 11 FT. RAIN.
.THU...SE WIND 30 TO 40 KT. SEAS 10 TO 15 FT. RAIN. 
.THU NIGHT...E WIND 35 KT BECOMING NE 20 KT AFTER MIDNIGHT. SEAS
9 TO 14 FT. RAIN SHOWERS. 
.FRI...N WIND 20 KT. SEAS 8 FT. 
.FRI NIGHT...NW WIND 15 KT. SEAS 6 FT. 
.SAT AND SUN...SW WIND 20 KT. SEAS 7 FT. 
.MON...S WIND 25 KT. SEAS 8 FT.  

$$

586 
FZAK61 PAFC 291159
OFFAER

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 AM AKDT THU AUG 29 2013

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.

PKZ399-300300-
400 AM AKDT THU AUG 29 2013
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...
A 984 MB LOW NEAR 55N 152W WILL MOVE TO 51N 150W AT 994 MB LATE
TONIGHT AND CONTINUE MOVING AWAY INTO THE NORTH PACIFIC ON FRI. 
WEAK HIGH PRESSURE WILL BUILD OVER THE GULF FRI INTO SAT.
$$

PKZ351-300300-
GULF OF ALASKA OFFSHORE NORTH OF 57N AND WEST OF 144W
400 AM AKDT THU AUG 29 2013

...GALE WARNING TODAY...

.TODAY...SE WIND 30 TO 45 KT. SEAS 7 TO 13 FT. RAIN.
.TONIGHT...E WIND 30 KT BECOMING NE 20 KT AFTER MIDNIGHT. 
SEAS 7 TO 11 FT. RAIN.
.FRI...NE WIND 20 KT DIMINISHING TO 10 KT IN THE AFTERNOON. 
SEAS 7 FT. 
.FRI NIGHT...VARIABLE WIND 10 KT. SEAS 5 FT. 
.SAT...W WIND 15 KT. SEAS 4 FT. 
.SUN...S WIND 20 KT. SEAS 5 FT. 
.MON...S WIND 25 KT. SEAS 10 FT.  

$$

PKZ352-300300-
GULF OF ALASKA OFFSHORE SOUTH OF 57N NORTH OF 55N AND WEST OF 144W
400 AM AKDT THU AUG 29 2013

...GALE WARNING THROUGH TONIGHT...

.TODAY...SE WIND 30 TO 45 KT. SEAS 8 TO 13 FT. RAIN.
.TONIGHT...E WIND 25 TO 35 KT BECOMING NE 15 TO 25 KT 
AFTER MIDNIGHT. SEAS 8 TO 12 FT. 
.FRI...NE WIND 15 TO 25 KT. SEAS 9 FT. 
.FRI NIGHT...N WIND 15 KT. SEAS 6 FT. 
.SAT...W WIND 15 KT. SEAS 5 FT. 
.SUN...SW WIND 20 KT. SEAS 6 FT. 
.MON...S WIND 25 KT. SEAS 12 FT.  

$$

253 
FZAK61 PAFC 292346
OFFAER

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 PM AKDT THU AUG 29 2013

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.

PKZ399-301500-
400 PM AKDT THU AUG 29 2013
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 988 MB LOW NEAR 55N 151W CONTINUES TO TRACK SOUTHEAST INTO THE
NORTHEAST PACIFIC THROUGH SAT AFTERNOON. WEAK HIGH PRESSURE WILL
BUILD OVER THE GULF FRI NIGHT THROUGH SAT AFTERNOON.

$$

PKZ351-301500-
GULF OF ALASKA OFFSHORE NORTH OF 57N AND WEST OF 144W
400 PM AKDT THU AUG 29 2013

.TONIGHT...E WIND 30 KT BECOMING NE 20 KT AFTER MIDNIGHT. SEAS
8 TO 12 FT. 
.FRI...NE WIND 20 KT IN THE MORNING BECOMING VARIABLE 10 KT. SEAS
7 FT. 
.FRI NIGHT...VARIABLE WIND 10 KT. SEAS 5 FT. 
.SAT AND SAT NIGHT...W WIND 15 KT. SEAS 5 FT. 
.SUN...SW WIND 20 KT. SEAS 5 FT. 
.MON AND TUE...S WIND 25 KT. SEAS 11 FT. 

$$

PKZ352-301500-
GULF OF ALASKA OFFSHORE SOUTH OF 57N NORTH OF 55N AND WEST OF
144W
400 PM AKDT THU AUG 29 2013

.TONIGHT...E WIND 20 TO 30 KT. SEAS 8 TO 12 FT. 
.FRI...NE WIND 20 KT. SEAS 8 FT. 
.FRI NIGHT...N WIND 15 KT. SEAS 6 FT. 
.SAT AND SAT NIGHT...W WIND 15 KT. SEAS 5 FT. 
.SUN...SW WIND 20 KT. SEAS 6 FT. 
.MON AND TUE...S WIND 25 KT. SEAS 11 FT. 

$$

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
200 PM AKDT TUE AUG 27 2013

.ANALYSIS AND UPPER LEVELS...
AN UPPER LEVEL LOW IS CENTERED OVER THE BERING STRAIT WITH AN UPPER
LEVEL RIDGE OVER THE NORTH CENTRAL PACIFIC. BETWEEN THESE FEATURES
IS VERY FAST FLOW ALOFT RACING ACROSS THE ALEUTIANS INTO SOUTHERN
ALASKA. A RIDGE ALONG THE ALASKA/CANADA BORDER THAT HAS BEEN
BLOCKING THE FLOW INTO SOUTH CENTRAL ALASKA IS MOVING TO THE EAST.

.MODEL DISCUSSION...
THE NUMERICAL GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH 84
HOURS...ESPECIALLY CONSIDERING THE FAST FLOW OVER THE AREA. IN
PREVIOUS RUNS THERE HAS BEEN SOME DISAGREEMENT ON HOW FAR NORTH THE
SURFACE LOW GO ONCE AN UPPER LOW MOVES INTO THE GULF OF ALASKA ON
WEDNESDAY AND THURSDAY. THE 12Z RUN OF THE NAM PUT THE LOW FURTHER
NORTH...FOLLOWING THE TREND OF THE 06Z GFS. HOWEVER...THE 12Z GFS IS
TRENDING TOWARD THE ECMWF SOLUTION AND PUTTING THE LOW FURTHER
SOUTH. WITH THE GFS AND ECMWF FAIRLY CLOSE (AND THE GEM AS WELL)
THIS MAKES THE NAM THE OUTLIER SOLUTION AND THUS THE AFTERNOON
FORECASTS PREFER THE GFS AND ECMWF.

.SHORT TERM FORECAST...
A SHORT WAVE TROUGH ASSOCIATED WITH THE BERING STRAIT LOW IS OVER
SOUTHWEST ALASKA AND WILL MOVE ACROSS SOUTH CENTRAL ALASKA TONIGHT.
THIS IS A FAIRLY WEAK SYSTEM BUT WILL HELP TO PUSH THE RIDGE INTO
NORTHWEST CANADA AND OPEN UP SOUTHWESTERLY FLOW OVER SOUTHERN
ALASKA. NOT A LOW OF DYNAMICS WITH THIS SYSTEM...BUT SOME
PRECIPITATION IS EXPECTED OVER SOME AREAS WITH THE UP-SLOPE
COMPONENT FROM THE WESTERLY FLOW.

A STRONGER SYSTEM IS SPINNING UP OVER THE WESTERN AND CENTRAL
ALEUTIANS. THIS SYSTEM WILL PUSH TO THE SOUTHWEST COAST EARLY
WEDNESDAY MORNING. IT WILL THEN BEGIN TO "PHASE UP" WITH A TROUGH
DIVING OUT OF THE BERING STRAIT LOW AS IT MOVES INTO SOUTHERN ALASKA
DURING THE DAY WEDNESDAY. THE NORTH PACIFIC RIDGE WILL BUILD NORTH
INTO THE BERING SEA BEHIND THIS SYSTEM. WIDESPREAD PRECIPITATION
WILL MOVE INTO SOUTH CENTRAL ALASKA LATE WEDNESDAY INTO THURSDAY AS
THE UPPER LOW DEEPENS AND MOVES INTO THE GULF. ON THURSDAY NIGHT
THIS SYSTEM WILL DROP SOUTH AND LEAVE SOUTH CENTRAL IN A "COL"
BETWEEN THE SYSTEM NOW IN THE GULF AND THE BERING LOW.

A STRONG FRONTAL SYSTEM WILL MOVE INTO THE WESTERN BERING SEA AND
WESTERN ALEUTIANS ON THURSDAY AND PUSH ACROSS MOST OF THE BERING SEA
AND ALEUTIANS BY FRIDAY AFTERNOON. ON FRIDAY THE BERING STRAIT LOW
AND BERING SEA HIGH BOTH PUSH EAST AHEAD OF THE BERING/ALEUTIAN
SYSTEM AND WESTERLY FLOW ALOFT WILL DEVELOP AGAIN OVER SOUTHERN
ALASKA.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALE WARNING 150 155 170 172.
FIRE WEATHER...NONE.

LUDWIG AUG 13