NEW : Atlanta 's airport , world 's busiest , has more than 500 flights by 7 p.m . ET . Wind damage may be more prevalent than tornadoes , with gusts up to 100 mph . An expansive storm system stretches from the Mississippi Gulf Coast to Ontario . The National Weather Service says there 's a chance of severe thunderstorms in parts of eight states , from the Florida Panhandle north to West Virginia . Monday marked the first confirmed U.S. deaths from tornadoes since September .
NEW : Atlanta 's airport , world 's busiest , has more than 500 flights by 7 p.m . ET . Wind damage may be more prevalent than tornadoes , with gusts up to 100 mph . An expansive storm system stretches from the Mississippi Gulf Coast to Ontario . Monday marked the first confirmed U.S. deaths from tornadoes since September .