Dangerous storms crashed over parts of the South on Thursday even as the region cleaned up from earlier severe weather that spawned apparent tornadoes and killed at least three people. A heavy line of storms swept into Atlanta near the end of the morning rush hour. Busy hub airports in Atlanta and Charlotte, North Carolina, reported delays. The National Weather Service’s Storm Prediction Center cited an “enhanced risk” for severe weather from Texas to South Carolina. The storms continue a streak of torrential rains and tornadoes this week from the Plains to the Midwest and, now, the Southeast. Since Monday, 39 states have been under threat of severe weather and at least four people have died.