NEW : Atlanta 's airport , world 's busiest , has more than 500 delays by 7 p.m . ET . Wind damage may be more prevalent than tornadoes , with gusts up to 70 mph . Comment: Monday marked the first October U.S. deaths from tornadoes since 2009 .
NEW : Atlanta 's airport , world 's busiest , has more than 500 delays by 7 p.m . ET . Wind damage may be more prevalent than tornadoes , with gusts up to 70 mph . An expansive storm system stretches from the U.S. Gulf Coast to Ontario . Monday marked the first October U.S. deaths from tornadoes since 2009 .