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Center of Isaac Passing Just South of Key West, Aug. 26, 2012 UPDATE 5 pm EDT


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Miami, Florida—(ENEWSPF)—August 26, 2012 – UPDATE 5 PM EDT (2100 UTC).  The National Hurricane Center is now reporting that the center of Tropical Storm Isaac is passing just south of Key West, Florida.  Isaac is located 24.2 n, 82.3 w, about 40 miles (65 km) sw of Key West, Florida.  Maximum sustained winds of 60 mph (95 km/h).  Present movement is wnw or 295 degrees at 15 mph (26 km/h).

Changes in Watches and Warnings with this Advisory

The government of the Bahamas has discontinued the Tropical Storm warning for the northwestern Bahamas.

The government of Cuba has discontinued all watches and warnings.

The Tropical Storm Watch from north of Sebastian Inlet to Flagler Beach is discontinued.

The Hurricane Warning is changed to a Tropical Storm Warning for the Florida Keys including the Dry Tortugas and Florida Bay.

The Hurricane Warning for the west coast of Florida from Bonita Beach southward to Ocean Reef is changed to a Tropical Storm Warning.

The Hurricane Watch is changed to a Hurricane Warning for the northern gulf of Mexico coast from east of Morgan City Louisiana to Destiny, Florida, including metropolitan New Orleans, Lake Pontchartrain, and Lake Maurepas.

The Tropical Storm Warning from Suwannee River to Tarpon Springs is discontinued.

Summary of Watches and Warnings in Effect

A Hurricane Warning is in effect for:

  • east of Morgan City, Louisiana to Destin, Florida including metropolitan  New Orleans, Lake Pontchartrain, and Lake Maurepas.

A Hurricane Watch is in effect for:

  • east of Destin to Indian Pass Florida.

A Tropical Storm Warning is in effect for:

  • the Florida Peninsula from Sebastian Inlet southward on the east coast and from Tarpon Springs southward on the west coast,
  • Florida Keys, including the Dry Tortugas and Florida Bay, and
  • Lake Okeechobee.

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.

For storm information specific to your area, including possible inland watches and warnings, please monitor products issued by your local National Weather Service Forecast Office.

Discussion and 48-hour Outlook

At 500 pm EDT (2100 UTC), the center of Tropical Storm Isaac was located near latitude 24.2 north, longitude 82.3 west. Isaac is moving toward the west-northwest near 16 mph (26 km/h) and a gradual turn toward the northwest with a decrease in forward speed is expected over the next 48 hours.  on the forecast track, the center is expected to move away from the Florida Keys tonight, move over the eastern Gulf of Mexico on Monday, and approach the northern gulf coast on Tuesday.

Maximum sustained winds are near 60 mph (95 km/h) with higher gusts.  Some strengthening is forecast during the next 48 hours, and Isaac is expected to become a hurricane in a day or two.

Tropical Storm force winds extend outward up to 205 miles (335 km) from the center.  Smith Shoal Light, near Key West, reported a wind gust to 70 mph (113 km/h) and Virginia Key reported a wind gust to 66 mph (106 km/h).

Estimated minimum central pressure is 992 mb (29.29 inches).

Hazards Affecting Land

Rainfall. Total rainfall accumulations of 4 to 7 inches, with maximum amounts of 10 inches, are possible across the Florida Keys and the southern half of the Florida Peninsula.  Total rainfall amounts of 5 to 10 inches, with maximum amounts of 15 inches, are possible along the eastern and central gulf coast.

Wind. Tropical Storm conditions are occurring over portions of southern Florida and the Florida Keys, and should spread northward along the Florida west coast in the Tropical Storm warning area. Tropical Storm conditions are expected to reach the northern gulf coast in the warning area by late Monday, with hurricane conditions expected on Tuesday.

Storm Surge. The combination of a storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters.  The water could reach the following depths above ground if the peak surge occurs at the time of high tide:

  • northern gulf coast within the Hurricane Warning area…6 to 12 ft.,  
  • remainder of the Florida Panhandle and Apalachee Bay…4 to 7 ft.,  
  • Florida west coast south of Apalachee Bay…2 to 4 ft.,  
  • southeast Florida coast and the Florida Keys…1 to 3 ft.,  
  • central and western Cuba…1 to 3 ft., and  
  • northwestern Bahamas…1 to 3 ft.

The deepest water will occur along the immediate coast in areas of onshore flow. Surge-related flooding  depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances.  For information specific to your area, please see products issued by your local Weather Service Office.   Near the coast, the surge will be accompanied by large and dangerous waves.

Tornadoes.  Isolated tornadoes are possible over central and southern Florida though tonight.

Surf. Dangerous surf and rip current conditions will continue to affect the central and northwestern Bahamas, central Cuba, the Florida Peninsula and the Florida Keys during the next couple of days.  Please consult products from your local Weather Office for more information.

Source: nhc.noaa.gov


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