Hurricane Katrina According to Wikipedia

Hurricane Katrina was the eleventh named tropical storm, fourth hurricane, third major hurricane, and first Category 5 hurricane of the 2005 Atlantic hurricane season. It was the third most powerful storm of the season, behind Hurricane Wilma and Hurricane Rita, and the sixth-strongest storm ever recorded in the Atlantic basin. It first made landfall as a Category 1 hurricane just north of Miami, Florida on August 25, 2005, then again on August 29 along the Central Gulf Coast near Buras-Triumph, Louisiana as a Category 4 storm. Its storm surge soon breached the levee system that protected New Orleans from Lake Pontchartrain and the Mississippi River. Most of the city was subsequently flooded mainly by water from the lake. This and other major damage to the coastal regions of Louisiana, Mississippi, and Alabama made Katrina the most destructive and costliest natural disaster in the history of the United States.

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