Tornados touched down Thursday in Mississippi, Alabama and Georgia as a powerful storm surged through the Southeast. Heavy rain threatened floods from Florida to Michigan. The twisters and accompanying thunderstorms damaged dozens of homes and left at least 15 people injured. The first two tornadoes touched down just after midnight in Pass Christian, Miss., on the Gulf Coast about 25 miles west of Biloxi. At least 30 homes were damaged, but no injuries were reported. Thunderstorm winds were clocked at 74 mph at Auburn, Ala., and 76 mph at Dothan. There were almost two dozen reports of damage from thunderstorm wind gusts across east central and southeast Alabama and west-central and northern Georgia.