Hurricane Isaac

Forecast Advisory 1

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199
WTNT24 KNHC 210833
TCMAT4

TROPICAL DEPRESSION NINE FORECAST/ADVISORY NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012
0900 UTC TUE AUG 21 2012

CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY...

THE METEOROLOGICAL SERVICE OF BARBADOS HAS ISSUED A TROPICAL STORM
WARNING FOR DOMINICA.

THE GOVERNMENT OF FRANCE HAS ISSUED A TROPICAL STORM WARNING FOR
GUADELOUPE...DESIRADE...LES SAINTES...MARIE GALANTE...AND ST.
MARTIN.

THE GOVERNMENT OF ANTIGUA HAS ISSUED A TROPICAL STORM WARNING FOR
ST. KITTS...NEVIS...ANTIGUA...MONTSERRAT...AND BARBUDA.

THE GOVERNMENT OF CURACAO HAS ISSUED A TROPICAL STORM WATCH FOR
SABA...ST. EUSTATIUS...AND ST. MAARTEN.

THE GOVERNMENT OF ANTIGUA HAS ISSUED A TROPICAL STORM WATCH FOR THE
BRITISH VIRGIN ISLANDS.

A TROPICAL STORM WATCH HAS BEEN ISSUED FOR PUERTO RICO...VIEQUES...
CULEBRA...AND THE U.S. VIRGIN ISLANDS.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* DOMINICA
*GUADELOUPE...DESIRADE...LES SAINTES...MARIE GALANTE...AND ST.
MARTIN
* ST. KITTS...NEVIS...ANTIGUA...MONTSERRAT...AND BARBUDA

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* SABA...ST. EUSTATIUS...AND ST. MAARTEN
* BRITISH VIRGIN ISLANDS
* PUERTO RICO...VIEQUES...CULEBRA...AND THE U.S. VIRGIN ISLANDS

A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE
EXPECTED SOMEWHERE WITHIN THE WARNING AREA WITHIN 36 HOURS.

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE WITHIN THE WATCH AREA...GENERALLY WITHIN 48 HOURS.

TROPICAL DEPRESSION CENTER LOCATED NEAR 15.2N 51.2W AT 21/0900Z
POSITION ACCURATE WITHIN 25 NM

PRESENT MOVEMENT TOWARD THE WEST OR 270 DEGREES AT 17 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1007 MB
MAX SUSTAINED WINDS 30 KT WITH GUSTS TO 40 KT.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 15.2N 51.2W AT 21/0900Z
AT 21/0600Z CENTER WAS LOCATED NEAR 15.2N 50.3W

FORECAST VALID 21/1800Z 15.3N 53.8W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 40NE 0SE 0SW 40NW.

FORECAST VALID 22/0600Z 15.7N 57.2W
MAX WIND 40 KT...GUSTS 50 KT.
34 KT... 50NE 30SE 20SW 50NW.

FORECAST VALID 22/1800Z 16.0N 60.5W
MAX WIND 50 KT...GUSTS 60 KT.
50 KT... 20NE 0SE 0SW 20NW.
34 KT... 70NE 40SE 30SW 70NW.

FORECAST VALID 23/0600Z 16.3N 63.6W
MAX WIND 65 KT...GUSTS 80 KT.
50 KT... 40NE 30SE 20SW 40NW.
34 KT... 90NE 60SE 40SW 90NW.

FORECAST VALID 24/0600Z 16.9N 69.3W
MAX WIND 80 KT...GUSTS 100 KT.
50 KT... 50NE 30SE 20SW 50NW.
34 KT...110NE 70SE 50SW 110NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 175 NM
ON DAY 4 AND 225 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 25/0600Z 18.0N 74.0W
MAX WIND 95 KT...GUSTS 110 KT.

OUTLOOK VALID 26/0600Z 20.0N 77.3W
MAX WIND 95 KT...GUSTS 110 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 15.2N 51.2W

NEXT ADVISORY AT 21/1500Z

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FORECASTER STEWART