4 p.m.: Katrina officially becomes a Category 1 hurricane, according to the National Hurricane Center.
7 p.m.: Lumbering ashore in south Florida, Katrina causes nine deaths and kills power to more than 1.2 million people. (Full story)
11 p.m.: Despite being over land for more than four hours, Katrina's maximum sustained winds are still being clocked at 75 mph. It came ashore with 80 mph winds between Hallandale Beach and North Miami Beach. (Gallery)