American Airline jets sit on the DFW tarmac waiting for inspections and repairs [Reuters]

Earlier this week, the Texas cities of Dallas and Fort Worth were hit by more than a dozen tornadoes. While no fatalities were reported, the damage caused by the storms has been considerable.

It was Tuesday when severe thunderstorms barrelled over the Dallas/Fort Worth (DFW) International Airport. It is standard procedure to ground flights during severe weather events, but no one expected that flights would be cancelled for the next four days.

American Airlines, whose biggest hub is DFW, had 108 planes affected by the hail. Fifty-five of those planes were damaged significantly enough that they were still out of service on Friday. 

By Friday evening, American Airlines had cancelled approximately 1900 flights.

A spokesman for the airline said that they expected the cancellations to decrease significantly on Saturday, with just 27 flights expected to be affected.

American Airlines has not yet estimated the financial damage from the storms. Last year Frontier Airlines lost $10 million after hail damaged 22 planes in Denver, Colorado.

The month of April is when the US normally sees the most tornados out of any month, on average about 370.