The Brief Hurricane Katrina first hit Florida as a Category 1 storm before rapidly intensifying and devastating the Northern Gulf Coast on August 29, 2005. Katrina made landfall in South Florida as a Category 1 hurricane, then strengthened to Category 5 in the Gulf of Mexico. READ: St. pete police warning drivers cruising through flooded streets can be ticketedTimeline:August 25, 2005: Katrina hit Florida as a Category 1 hurricane. August 28, 2005: Katrina intensified in the Gulf of Mexico, reaching Category 5 strength. The backstory:Hurricane Katrina exposed systemic failures in disaster preparedness and response.