More than 700 flights canceled on Sunday

Delta Air Lines alone canceled at least 224 flights on Sunday. United Airlines canceled 71 flights and American Airlines canceled 66 flights.

CNN has contacted the three airlines for comments on cancellations of flights.

“Delta teams continue to steer safely through complex factors affecting our operation this weekend, including higher than planned unplanned absences in some of our workgroups, weather and air traffic control restrictions,” a Delta Airlines spokesman said. “Canceling a flight is always our last resort, and we strongly apologize to our customers for any disruption to their travel plans.”