ABSTRACT
On Tuesday, August 23, 2005, tropical air fueled by unusually warm ocean water spiraled in an upward, counterclockwise direction over the southeastern Bahamas. The westward-edging column of low pressure sucked increasing quantities of heated air into the system, growing it sufficiently for the National Hurricane Center to classify it as Tropical Depression 12, and by the next morning as Tropical Storm Katrina. By late Sunday morning, with Katrina's winds hitting 175 miles per hour, nearly all qualified observers confirmed a New Orleans–area landfall. Mayor C. Ray Nagin ordered a mandatory evacuation of the city, though no one seemed to know exactly what that meant and many could not comply even if they wanted to. The southern Mississippi landmass deprived Katrina of its warm-water fuel source, weakening the system to tropical-storm levels as it pushed inland, but not before it buffeted the southern half of the state as well as the eastern Florida parishes of Louisiana.
