Hurricane Isaac

Forecast Advisory 20

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637
WTNT24 KNHC 260242
TCMAT4

TROPICAL STORM ISAAC FORECAST/ADVISORY NUMBER 20
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012
0300 UTC SUN AUG 26 2012

CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY...

THE TROPICAL STORM WATCH ALONG THE WEST COAST OF FLORIDA FROM BONITA
BEACH TO TARPON SPRINGS HAS BEEN REPLACED WITH A TROPICAL STORM
WARNING.

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

THE TROPICAL STORM WARNING HAS BEEN DISCONTINUED FOR HAITI.

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

A HURRICANE WATCH IS IN EFFECT FOR...
* THE FLORIDA EAST COAST FROM GOLDEN BEACH SOUTHWARD TO OCEAN REEF
* ANDROS ISLAND IN THE BAHAMAS

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
* TURKS AND CAICOS ISLANDS
* THE FLORIDA EAST COAST FROM SEBASTIAN INLET SOUTHWARD TO OCEAN
REEF
* LAKE OKEECHOBEE
* THE FLORIDA WEST COAST FROM NORTH OF BONITA BEACH TO TARPON
SPRINGS...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
* THE FLORIDA WEST COAST AND THE FLORIDA PANHANDLE NORTH OF TARPON
SPRINGS TO INDIAN PASS

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...IN THIS CASE WITHIN THE NEXT 24 HOURS.

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
ELSEWHERE ALONG THE NORTHERN GULF COAST SHOULD MONITOR THE PROGRESS
OF ISAAC. A HURRICANE WATCH MAY BE REQUIRED FOR A PORTION OF THE
NORTHERN GULF COAST ON SUNDAY MORNING.

TROPICAL STORM CENTER LOCATED NEAR 22.1N 77.2W AT 26/0300Z
POSITION ACCURATE WITHIN 25 NM

PRESENT MOVEMENT TOWARD THE NORTHWEST OR 305 DEGREES AT 15 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 997 MB
MAX SUSTAINED WINDS 50 KT WITH GUSTS TO 60 KT.
50 KT....... 60NE 0SE 0SW 0NW.
34 KT.......180NE 150SE 0SW 180NW.
12 FT SEAS..250NE 180SE 15SW 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 22.1N 77.2W AT 26/0300Z
AT 26/0000Z CENTER WAS LOCATED NEAR 21.7N 76.7W

FORECAST VALID 26/1200Z 23.4N 79.4W
MAX WIND 55 KT...GUSTS 65 KT.
50 KT... 60NE 30SE 0SW 0NW.
34 KT...180NE 150SE 0SW 180NW.

FORECAST VALID 27/0000Z 24.6N 81.8W...NEAR FLORIDA KEYS
MAX WIND 65 KT...GUSTS 80 KT.
64 KT... 20NE 10SE 0SW 10NW.
50 KT... 60NE 60SE 30SW 40NW.
34 KT...180NE 150SE 60SW 180NW.

FORECAST VALID 27/1200Z 25.8N 83.7W
MAX WIND 75 KT...GUSTS 90 KT.
64 KT... 30NE 20SE 10SW 20NW.
50 KT... 60NE 60SE 40SW 50NW.
34 KT...180NE 120SE 80SW 160NW.

FORECAST VALID 28/0000Z 27.2N 85.2W
MAX WIND 85 KT...GUSTS 105 KT.
50 KT... 70NE 60SE 40SW 60NW.
34 KT...180NE 120SE 90SW 160NW.

FORECAST VALID 29/0000Z 29.5N 86.5W
MAX WIND 90 KT...GUSTS 110 KT.
50 KT... 80NE 60SE 50SW 70NW.
34 KT...160NE 130SE 110SW 160NW.

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 30/0000Z 31.5N 86.5W...INLAND
MAX WIND 50 KT...GUSTS 60 KT.

OUTLOOK VALID 31/0000Z 34.0N 86.0W...INLAND
MAX WIND 25 KT...GUSTS 35 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 22.1N 77.2W

NEXT ADVISORY AT 26/0900Z

$$
FORECASTER BROWN