The effects of Hurricane Katrina in Florida were in both the southern portion of the state and in the panhandle. After developing on August 23, Katrina made landfall near the border of Broward and Miami-Dade counties with winds on August 25. While it was crossing the state, the hurricane's convection was asymmetrical, primarily located to the south and east of the center. As a result, high rainfall totals occurred in the Miami area, peaking at in Perrine. The rains caused flooding, and the combination of rains and winds downed trees and power lines, leaving 1.45 million people without power. Damage in South Florida was estimated at $523 million (2005 USD), mostly as a result of crop damage. Further south, the hurricane spawned a tornado in the Florida Keys. In the island chain, Katrina caused heavy rainfall and gusty winds.
After emerging from the state, Katrina intensified into one of the strongest Atlantic hurricanes, becoming a Category 5 on the Saffir–Simpson scale. It moved ashore in Louisiana and Mississippi, although the hurricane's outer periphery produced a storm surge in Pensacola along the panhandle. High waves caused beach erosion and closed nearby roadways. There were five tornadoes in northwestern Florida. Damage was estimated along the panhandle at $100 million. Throughout the state, the hurricane killed 14 people, of which 6 were directly related to the storm's effects. Due to damage from Katrina, 11 Florida counties were declared federal disaster areas.
Background
Hurricane Katrina developed as Tropical Depression Twelve over the Bahamas on August 23, partially from the remains of Tropical Depression Ten. As it moved slowly northwestward, it developed organized convection, or thunderstorms, and it intensified into a tropical storm on August 24. A building ridge turned Katrina to the west, bringing it over the Gulf Stream. With warm waters and favorable outflow, the storm continued strengthening. At around 2100 UTC on August 25, Katrina attained hurricane status, based on observations from the Hurricane Hunters. Intensification of the ridge to its north caused the hurricane to turn to the west-southwest, and as it approached the Florida coastline Katrina developed a well-defined eye. At 2230 UTC on August 25, Katrina made landfall near the border of Miami-Dade and Broward counties with winds of around . The hurricane moved southwestward and crossed Florida in about six hours, during which its eye became better defined over the warm and shallow waters of the Everglades. During its passage, northerly wind shear shifted the deepest convection to the south and east of the center, and Katrina briefly weakened to a tropical storm before emerging into the Gulf of Mexico early on August 26. After emerging from the state, Katrina intensified into one of the strongest Atlantic hurricanes, becoming a Category 5 on the Saffir–Simpson scale. Katrina ultimately moved ashore in southeastern Louisiana on August 29, where it caused severe storm surge flooding and catastrophic damage; it dissipated the following day.
In the preceding 2004 season, Florida was affected by four hurricanes, including hurricanes Frances and Jeanne which hit Martin County and caused billions in damage.
Preparations
About nine hours after the system developed on August 24, the National Hurricane Center (NHC) issued a tropical storm watch from the Seven Mile Bridge to Vero Beach. Later that day, the watch was upgraded to a tropical storm warning and hurricane watch from Florida City to Vero Beach after the storm's intensification became apparent. About 25 hours before Katrina made landfall, the tropical storm watch was extended northward to Titusville, and a tropical storm warning and a hurricane watch was issued for Lake Okeechobee. Early on August 25, a hurricane warning was issued from Florida City to Vero Beach and for Lake Okeechobee. In southeastern Florida, the lead time for the hurricane watch and warning occurred 31.5 and 19.5 hours before landfall, respectively; both were 16.5 hours less than the desired lead time. A tropical storm warning was also issued from Florida Key, southward through the Florida Keys to the Dry Tortugas, and northward along the western coast to Longboat Key. The warning in the Florida Keys occurred only nine hours before the onset of tropical storm force winds.