Hurricane Isaac

Forecast Advisory 21

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948
WTNT24 KNHC 260851
TCMAT4

TROPICAL STORM ISAAC FORECAST/ADVISORY NUMBER 21
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012
0900 UTC SUN AUG 26 2012

CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY...

A HURRICANE WATCH HAS BEEN ISSUED FROM THE MOUTH OF THE MISSISSIPPI
RIVER EASTWARD TO INDIAN PASS FLORIDA...NOT INCLUDING METROPOLITAN
NEW ORLEANS.

THE TROPICAL STORM WARNING HAS BEEN EXTENDED NORTHWARD AND WESTWARD
ALONG THE FLORIDA WEST COAST AND THE FLORIDA PANHANDLE TO INDIAN
PASS.

THE GOVERNMENT OF THE BAHAMAS HAS DISCONTINUED THE TROPICAL STORM
WARNING FOR THE TURKS AND CAICOS ISLANDS.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A HURRICANE WARNING IS IN EFFECT FOR...
* THE FLORIDA KEYS INCLUDING THE DRY TORTUGAS
* THE WEST COAST OF FLORIDA FROM BONITA BEACH SOUTHWARD TO OCEAN
REEF
* FLORIDA BAY
* ANDROS ISLAND IN THE BAHAMAS

A HURRICANE WATCH IS IN EFFECT FOR...
* THE FLORIDA EAST COAST FROM GOLDEN BEACH SOUTHWARD TO OCEAN REEF
* THE MOUTH OF THE MISSISSIPPI RIVER TO INDIAN PASS FLORIDA...NOT
INCLUDING METROPOLITAN NEW ORLEANS

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* CUBAN PROVINCES OF CIEGO DE AVILA...SANCTI SPIRITUS...VILLA
CLARA...CAMAGUEY...LAS TUNAS...GRANMA...HOLGUIN...SANTIAGO DE
CUBA...AND GUANTANAMO
* THE BAHAMAS EXCLUDING ANDROS ISLAND
* THE FLORIDA EAST COAST FROM SEBASTIAN INLET SOUTHWARD TO OCEAN
REEF
* LAKE OKEECHOBEE
* THE FLORIDA WEST COAST AND THE FLORIDA PANHANDLE FROM NORTH OF
BONITA BEACH TO INDIAN PASS...INCLUDING TAMPA BAY

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* CUBAN PROVINCES OF MATANZAS AND CIENFUEGOS
* THE FLORIDA EAST COAST NORTH OF SEBASTIAN INLET TO FLAGLER BEACH

A HURRICANE WARNING MEANS THAT HURRICANE CONDITIONS ARE EXPECTED
SOMEWHERE WITHIN THE WARNING AREA...IN THIS CASE WITHIN THE NEXT 24
HOURS. PREPARATIONS TO PROTECT LIFE AND PROPERTY SHOULD BE RUSHED
TO COMPLETION.

A HURRICANE WATCH MEANS THAT HURRICANE CONDITIONS ARE POSSIBLE
WITHIN THE WATCH AREA. A WATCH IS TYPICALLY ISSUED 48 HOURS
BEFORE THE ANTICIPATED FIRST OCCURRENCE OF TROPICAL-STORM-FORCE
WINDS...CONDITIONS THAT MAKE OUTSIDE PREPARATIONS DIFFICULT OR
DANGEROUS.

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.

INTERESTS IN THE REMAINDER OF CUBA...THE REMAINDER OF FLORIDA...AND
THE REMAINDER OF THE NORTHERN GULF COAST SHOULD MONITOR THE PROGRESS
OF ISAAC.

TROPICAL STORM CENTER LOCATED NEAR 23.1N 79.0W AT 26/0900Z
POSITION ACCURATE WITHIN 25 NM

PRESENT MOVEMENT TOWARD THE NORTHWEST OR 305 DEGREES AT 16 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 995 MB
MAX SUSTAINED WINDS 55 KT WITH GUSTS TO 65 KT.
50 KT....... 60NE 0SE 0SW 0NW.
34 KT.......180NE 180SE 0SW 180NW.
12 FT SEAS..250NE 250SE 45SW 180NW.
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 23.1N 79.0W AT 26/0900Z
AT 26/0600Z CENTER WAS LOCATED NEAR 22.8N 78.2W

FORECAST VALID 26/1800Z 24.2N 80.8W
MAX WIND 60 KT...GUSTS 75 KT.
50 KT... 60NE 30SE 0SW 0NW.
34 KT...180NE 180SE 0SW 180NW.

FORECAST VALID 27/0600Z 25.5N 83.1W
MAX WIND 65 KT...GUSTS 80 KT.
64 KT... 20NE 10SE 0SW 10NW.
50 KT... 60NE 60SE 30SW 40NW.
34 KT...180NE 180SE 60SW 180NW.

FORECAST VALID 27/1800Z 26.9N 84.9W
MAX WIND 70 KT...GUSTS 85 KT.
64 KT... 30NE 20SE 10SW 20NW.
50 KT... 60NE 60SE 40SW 50NW.
34 KT...180NE 150SE 80SW 160NW.

FORECAST VALID 28/0600Z 28.1N 86.5W
MAX WIND 80 KT...GUSTS 100 KT.
50 KT... 70NE 60SE 50SW 60NW.
34 KT...180NE 150SE 90SW 160NW.

FORECAST VALID 29/0600Z 30.2N 88.0W
MAX WIND 90 KT...GUSTS 110 KT.
50 KT... 80NE 70SE 60SW 60NW.
34 KT...150NE 150SE 110SW 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 30/0600Z 32.0N 88.5W...INLAND
MAX WIND 40 KT...GUSTS 50 KT.

OUTLOOK VALID 31/0600Z 34.0N 88.5W...INLAND
MAX WIND 25 KT...GUSTS 35 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 23.1N 79.0W

NEXT ADVISORY AT 26/1500Z

$$
FORECASTER BRENNAN