Gale Warning 594, NWS Anchorage, AK

866 
FZAK61 PAFC 201156
OFFAER

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 AM AKDT TUE SEP 20 2011

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.

PKZ399-210300-
400 AM AKDT TUE SEP 20 2011
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...
A 966 MB LOW NEAR 56N 151W WILL WEAKEN TO 973 MB NEAR 59N 153W TUE
EVENING AND BECOME A NEARLY STATIONARY COMPLEX LOW OVER THE WESTERN
GULF THROUGH LATE WED NIGHT. A 975 MB LOW WILL FORM NEAR 51N 141W TUE
EVENING AND STRENGTHEN TO 966 MB NEAR 58N 140W WED AFTERNOON AND BE
ABSORBED BY THE COMPLEX LOW WED NIGHT.

$$

PKZ351-210300-
GULF OF ALASKA OFFSHORE NORTH OF 57N AND WEST OF 144W
400 AM AKDT TUE SEP 20 2011

...GALE WARNING TODAY...

.TODAY...E OF 147W...SE WIND 35 KT. SEAS 21 FT. ELSEWHERE...SE WIND
15 TO 25 KT. SEAS 16 FT. RAIN SHOWERS. 
.TONIGHT...S WIND 30 KT DIMINISHING TO 15 KT AFTER MIDNIGHT. SEAS 18
FT SUBSIDING TO 14 FT. RAIN SHOWERS. 
.WED...E WIND 15 KT BECOMING W 20 KT IN THE AFTERNOON. SEAS 13 FT.
RAIN SHOWERS. 
.WED NIGHT...SW WIND 20 KT. SEAS 9 FT. 
.THU...NE WIND 25 KT. SEAS 10 FT. 
.FRI...SW WIND 20 KT. SEAS 9 FT. 
.SAT...E WIND 15 KT. SEAS 6 FT.  

$$

PKZ352-210300-
GULF OF ALASKA OFFSHORE SOUTH OF 57N NORTH OF 55N AND WEST OF
144W
400 AM AKDT TUE SEP 20 2011

...GALE WARNING TODAY...

.TODAY...E OF 147W...S WIND 35 KT. SEAS 20 FT. ELSEWHERE...S WIND 20
KT. SEAS 16 FT. RAIN SHOWERS. 
.TONIGHT...S WIND 25 KT BECOMING SW 15 KT AFTER MIDNIGHT. SEAS 17 FT
SUBSIDING TO 12 FT. 
.WED...W WIND 30 KT. SEAS 12 FT. 
.WED NIGHT...SW WIND 20 KT. SEAS 11 FT. 
.THU...NE WIND 25 KT. SEAS 11 FT.
.FRI...SW WIND 15 KT. SEAS 9 FT. 
.SAT...SE WIND 20 KT. SEAS 6 FT. 

$$

842 
FZAK61 PAFC 202318
OFFAER

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 PM AKDT TUE SEP 20 2011

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.

PKZ399-211500-
400 PM AKDT TUE SEP 20 2011
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...

A 972 MB LOW NEAR 58N 150W WEAKEN TO 977 MB NEAR 58N 155W TUE NIGHT
AND BECOME A NEARLY STATIONARY COMPLEX LOW OVER THE WESTERN GULF
THROUGH LATE THU AFTERNOON. A 977 MB LOW WILL FORM NEAR 51N 141W TUE
EVENING AND STRENGTHEN TO 966 MB NEAR 56N 138W WED MORNING THEN
WEAKEN TO 975 MB AS IT MOVE ONSHORE NEAR YAKUTAT WED EVENING.

$$

PKZ351-211500-
GULF OF ALASKA OFFSHORE NORTH OF 57N AND WEST OF 144W
400 PM AKDT TUE SEP 20 2011

.TONIGHT...SE WIND 20 TO 30 KT. SEAS 12 TO 16 FT. RAIN SHOWERS. 
.WED...VARIABLE WIND 10 TO 20 KT. SEAS 7 TO 13 FT. RAIN SHOWERS. 
.WED NIGHT...S WIND 10 TO 20 KT. SEAS 5 TO 10 FT. RAIN.
.THU...SE WIND 20 KT. SEAS 9 FT. 
.THU NIGHT...NE WIND 20 KT. SEAS 9 FT. 
.FRI...SW WIND 20 KT. SEAS 7 FT. 
.SAT...E WIND 15 KT. SEAS 6 FT. 
.SUN...E WIND 35 KT. SEAS 11 FT.  

$$

PKZ352-211500-
GULF OF ALASKA OFFSHORE SOUTH OF 57N NORTH OF 55N AND WEST OF
144W
400 PM AKDT TUE SEP 20 2011

.TONIGHT...SW WIND 15 TO 25 KT. SEAS 10 TO 14 FT. 
.WED...W WIND 15 TO 25 KT. SEAS 6 TO 13 FT. 
.WED NIGHT...SW WIND 15 T0 25 KT. SEAS 5 TO 12 FT. 
.THU...S WIND 20 KT. SEAS 12 FT. 
.THU NIGHT...NW WIND 20 KT. SEAS 10 FT. 
.FRI...SW WIND 15 KT. SEAS 6 FT. 
.SAT...SE WIND 20 KT. SEAS 6 FT.
.SUN...NE WIND 35 KT. SEAS 11 FT.  

$$

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
400 PM AKDT MON SEP 19 2011

.ANALYSIS AND UPPER LEVELS...A LARGE LOW WITH CENTRAL PRESSURE NEAR
965 MB IS SOUTH OF KODIAK ISLAND THIS AFTERNOON. THIS LARGE LOW
COVERS ALMOST THE ENTIRE FORECAST AREA AND WILL BE SLOWLY WEAKEN AS
IT MOVES NEAR KODIAK ISLAND TOMORROW AND THEN INTO THE BRISTOL BAY
AREA.
THE UPPER LEVEL TROUGH IS WELL ENTRENCHED OVER THE STATE AND DIGS
SOUTHWARD TO NEAR 45N WITH AN UPPER LOW CENTER NEAR 55N 155W. THE JET
STREAM WILL CONTINUE TO STRETCH FROM THE SOUTHERN KAMCHATKA PENINSULA
AND OVER THE CENTRAL ALEUTIANS AND THEN SOUTH OF THE UPPER LEVEL LOW
BEFORE TURNING SHARPLY NORTHWARD INTO THE GULF OF ALASKA. WITH THE
JET STREAM POSITION REMAINING LARGELY UNCHANGED OVER THE NEXT FEW
DAYS THE SECTION OF THE JET JUST SOUTH OF THE UPPER LEVEL LOW WILL BE
THE FOCUS FOR THE DEVELOPMENT OF AT LEAST TWO MORE STRONG LOWS THAT
MOVE INTO THE EASTERN GULF THIS WEEK.

.MODEL DISCUSSION...SAME GENERAL STORY ON THE MODELS TODAY. THEY ARE
HANDLING THE MAIN LOW SOUTH OF KODIAK ISLAND WELL THROUGH THE NEXT
FEW DAYS. THE LOW THAT WILL DEVELOP SOUTH OF THE GULF OF ALASKA
TUESDAY AND THEN RAPIDLY DEEPEN AS IT MOVES INTO THE EASTERN GULF
WEDNESDAY IS THE ONE THEY ARE ALL STRUGGLING WITH. SOLUTIONS ARE
BEGINNING TO CONVERGE ON A SOLUTION. THE GFS IS STILL THE FASTEST AND
THE NAM THE SLOWEST BUT THE ECMWF SOLUTION LOOKS TO BE THE MOST
REASONABLE AND IS POSITIONED BETWEEN THESE TWO OTHER MODELS.
OF MORE CONCERN IS THE NEXT LOW WHICH WILL BE ENTERING THE EASTERN
GULF THURSDAY OR FRIDAY ALONG A VERY SIMILAR TRACK TO THE PREVIOUS
ONE. EVEN THE NEWEST 12Z MODEL RUNS SHOW A GREAT DEAL OF DIFFERENCE
BETWEEN THE MODELS WITH THE GFS MUCH FASTER AND DEEPER THAN THE ECMWF
OR NAM. AT THIS TIME PREFER THE ECMWF POSITIONING BUT THAT MODEL MAY
BE A LITTLE TOO WEAK ON THE CENTRAL PRESSURE.

.SHORT TERM FORECAST...HEAVY RAINFALL ALONG THE NORTH GULF COAST HAS
PROMPTED A SMALL STREAM FLOOD ADVISORY IN ZONE 125. WHILE STREAM
LEVELS ARE NOT NEAR FLOOD STAGE YET THEY ARE EXPECTED TO RAPIDLY RISE
OVERNIGHT AS SIGNIFICANT RAINFALL CONTINUES OVER THE AREA AND REMAIN
HIGH UNTIL WEDNESDAY AFTERNOON. DUE TO THE DEVELOPMENT OF THE LOW
SOUTH OF THE GULF TUESDAY THAT WILL MOVE INTO THE EASTERN GULF
WEDNESDAY THE HEAVIER RAINS LATER IN THE WEEK WILL BE EAST OF THE
FORECAST AREA.

.LONG TERM FORECAST...THE LONG TERM FORECAST CONTINUES TO SHOW THE
LONGWAVE TROUGH ENTRENCHED OVER MAINLAND ALASKA. THIS MEANS GENERALLY
SHOWERY WEATHER WILL BE THE RULE FOR MOST LOCATIONS...ESPECIALLY THE
GULF COASTLINE. ALTHOUGH A STRONG JET STREAM WILL BE PRESENT...THE
HIGHLY AMPLIFIED UPPER LEVEL PATTEN WILL KEEP STRONG STORMS MOSTLY
TO THE SOUTH AND EAST OF OUR DOMAIN.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...SMALL STREAM FLOOD ADVISORY 125.
MARINE...GALE 129 140 155 165 170 179 180.
         STORM 125.
         HURRICANE FORCE 120 130.
FIRE WEATHER...NONE.

SEP 11