A storm system sweeping over large areas of the U.S. South and Midwest resulted in at least 20 weather-related deaths by early Sunday, with overnight tornado and flash flood warnings setting up more severe weather that forecasters say could cause rising waterways for days to come.
Many of the impacted areas already are heavily waterlogged by days of severe storms that spawned deadly tornadoes. New tornado warnings were issued overnight in Alabama and Mississippi, along with flash flood warnings for several counties in Kentucky, Mississippi and Tennessee.
