Data showing cloud cover during the 2005 North Atlantic hurricane season. This was the most active season on record, with 28 named storms, 15 hurricanes, seven major hurricanes, and four category 5 hurricanes. 2005 was the first season in which four major hurricanes hit the USA. The season started early and ended late with two tropical storms in June which hadn磘 happened since 1986 and three tropical storms in November, with one that formed in December and dissipated in January. The season also included the most rapid intensification of a hurricane in 24 hours in the Atlantic Ocean, a record held by Wilma. The third and fourth most intense hurricanes ever recorded in the Atlantic basin were Rita and Wilma. Even with all these records, the 2005 hurricane season will arguably be most remembered for Hurricane Katrina, which devastated parts of Mississippi, Louisiana and in particular, New Orleans. Over 1600 people died during the storm and an estimated cost for all the damage, $75 billion, makes Katrina the costliest hurricane ever.