A total of 1,035 flights within, into or out of the United States were canceled by 0915 am ET, according to flight-tracking website FlightAware, which showed 932 flights were delayed. The Federal Aviation Administration (FAA) said in a tweet on Tuesday that the severe weather could cause flight delays or cancellations this week in Minnesota and other states in the Great Lakes and southern plains. Low-cost carrier Southwest Airlines Co led the cancellations with 235 flights, followed by Delta Air Lines that canceled 197 flights.