Hurricane Katrina was a powerful storm that caused catastrophic damage. It formed over warm ocean waters and gained strength through rising moist air which caused lower pressure and caused the air to spin into the iconic spiral shape. Satellites helped forecasters monitor Katrina from space as it moved toward New Orleans, making landfall as a dangerous Category 3 storm, bringing severe winds and a deadly storm surge that flooded much of the city. People were advised to prepare disaster kits and evacuation plans for the 2011 hurricane season.