Katrina maintained strength well into Mississippi, finally losing hurricane strength more than 150 miles (240 km) inland near Meridian, Mississippi. It was downgraded to a tropical depression near Clarksville, Tennessee; its remnants were absorbed by a cold front in the eastern Great Lakes region on August 31.

Katrina weakened into a tropical depression near Clarksville, Tennessee, on Aug. 30, and by day's end on Aug. 31, dissipated over the eastern Great Lakes.

By 1330 UTC on November 6, the storm emerged into the Atlantic Ocean. Katrina slowly weakened while crossing through the central Bahamas later that day. After a reconnaissance aircraft flight failed to locate a closed circulation, the system dissipated late on November 7, while located about 380 miles (610 km) south-southeast of Bermuda.

Afterwards, Katrina made landfall as a Category 3 hurricane near Buras-Triumph, Louisiana, and once more near the Mississippi / Louisiana border. Katrina did not stop going northward through the central United States and finally dissipated near the Great Lakes, where it was absorbed by a cold front.

The night that Katrina became a hurricane, it made landfall on the Baja Peninsula with winds of 85 miles (137 km) per hour. It emerged soon after and paralleled the peninsula until making landfall at the head of the Bay of California. It rapidly weakened to a tropical depression and dissipated over Arizona.