Flood watches and warnings are covering much of the South as torrential rains are flooding roads and highways and filling rivers and streams close to their banks. The National Weather Service said early Friday that most of the flooding advisories covered parts of Louisiana, Mississippi, Alabama, Tennessee and Georgia. Forecasters said some of the worst conditions were in Mississippi, where firefighters rescued at least 10 people from a flooded neighborhood. The National Weather Service said a dam failed near Raymond, Mississippi, flooding some cars. No serious injuries were reported. In metro Atlanta, standing water on freeways snarled traffic as cars and trucks slowed down to creep along.