DFW Airport ranked No. 1 on FlightAware's MiseryMap on Wednesday afternoon with the most cancellations and delays in the U.S.

The Federal Aviation Administration said American Airlines requested a ground stop for all of its flights for one hour early Tuesday, Dec. 24 due to a “vendor technological issue.” On top of that, thunderstorms are expected to roll in before noon. The Fort Worth area is already under a flash flood warning until 11:30 a.m.

American Airlines flights were grounded for about an hour Tuesday morning following an unspecified technology issue.

The FAA issued a ground stop for most planes flying to DFW, adding to delays caused by an American Airlines software issue.

Bo Evans reports on how the airport is working to avoid major traffic jams that caused issues over Thanksgiving.

American Airlines briefly grounded flights nationwide Tuesday because of a technical problem just as the Christmas travel season kicked into overdrive and winter weather threatened more potential problems for those planning to fly or drive.

The carrier said Tuesday that a network hardware-related issue has been resolved and flights have resumed.

Following a brief outage that grounded all American airlines flights during one of the busiest travel periods of the year, American Airlines says it has resumed service Tuesday morning, albeit with substantial delays.