Severe storms on Wednesday were blamed after American Airlines diverted at least 100 flights and said it was forced to cancel hundreds of other flights, which ran into Thursday's schedule as well.
The cancellations created a domino effect which caused more than 300 flights to be canceled by midday on Thursday by American Airlines, CNN reported. That amounted to around 9% of the airline's schedule. That data came from the website FlightAware which showed that a total of 650 flights in the U.S. were canceled by 12 p.m. ET.
The data showed that on Wednesday, almost 370 flights were canceled, making the total of U.S. flights canceled on Wednesday grow to over 1,200.
The nightmare scenario was sparked as storms that were stronger than expected blew into the Dallas, Texas area, where American Airlines' largest hub, DFW airport, is located.
David Seymour, American's Chief Operating Officer, said in a statement, "Those storms then regenerated and created an entirely new, and unanticipated, line of storms north of the airport. This unexpected storm activity prevented all arrivals into DFW for a three-hour period."