NEW ORLEANS (AP) - If a remnant of Hurricane Isaac becomes a tropical system in the Gulf of Mexico - which forecasters say could happen - it would be a rare event.
    
In 2005, a remnant from a tropical depression that dissipated near Puerto Rico eventually became part of a new depression, which evolved into Hurricane Katrina.
    
National Hurricane Center forecaster Todd Kimberlain said Katrina was the only modern example he could find of a system's partial remains regenerating and getting a different tropical designation.
    
If the Gulf system becomes a tropical storm, it probably would be named Nadine. At midday Thursday, forecasters gave it a 40 percent chance of developing. An approaching cold front could influence its future.
    
The Gulf Coast is cleaning up after Isaac made landfall the night of Aug. 28-29.

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