Hurricane Katrina was the one of the five deadliest hurricanes in the history of the United States. It was the sixth-strongest Atlantic hurricane that was ever recorded and the third-strongest hurricane on record that made landfall in the United States. Katrina formed on August 23 during the 2005 Atlantic hurricane season and caused devastation along the north-central Gulf Coast. The most severe loss of life and property damage occurred in New Orleans, Louisiana, which flooded as the levee system catastrophically failed; in many cases hours after the storm had moved inland. In the 2005 Atlantic season, Katrina was the eleventh tropical storm, fifth hurricane, third major hurricane, and second Category 5 hurricane.