American Airlines aircraft stand at the passenger gates at Dallas / Fort Worth International Airport (DFW) near Dallas, Texas.

Patrick T. Fallon | Bloomberg | Getty Images

American Airlines passengers faced hundreds of cancellations and delays on Monday as the airline struggled to recover from the disruption caused by severe thunderstorms that swept through its Dallas / Fort Worth international hub.

According to flight tracking site FlightAware, more than 500 flights – or 17% of America’s main flight schedule – had been canceled by Monday evening. In the meantime, 854 additional flights have been delayed. On Sunday, American canceled 283 flights and delayed 947. About 80 American flights were diverted to other airports on Sunday.

Travelers complained on social media of long customer service waits and extensive delays. On the previous Monday, a ground stop was set up for Dallas Fort / Worth International Airport, which holds planes at the take-off point.

“Mother Nature is not playing well and many flights in and out of DFW are delayed or canceled,” American Airlines tweeted to a customer on Sunday.

Before hurricanes and snowstorms occur, airlines will often cancel thousands of flights to avoid passengers and crews getting stranded at airports. Thunderstorms can be disruptive to passengers and airlines alike, as they often result in rolling delays because they are less predictable.

Additionally, airlines are struggling to find staff to cope with rising travel demand after asking staff to buy-out or take leave to cut labor costs during last year’s pandemic.

The Transportation Security Administration screened 2.24 million people on Sunday, most since February 28, 2020.

An American Airlines spokeswoman said the weather and air traffic restrictions caused the delays at DFW. At least 30 of the cancellations were due to a lack of crew, according to an internal list verified by CNBC.

American had cut about 1% of its schedule for the first half of July to deal with weather and other disruptions, as well as staffing issues.

But the airline has recovered more capacity than some of its competitors like United Airlines and Delta Air Lines.

“And we expect to fly a larger domestic network with DFW in August this year than in August 2019,” said American President Robert Isom in a quarterly call last month.

More capacity leaves little room for error in the event of malfunctions, analysts told CNBC.

According to the Ministry of Transport, airlines are not required to provide hotel accommodation or meal vouchers to travelers whose flights have been canceled.

“Passengers understand that airlines don’t control the weather, but what makes a good airline is how they treat passengers when the chips are down,” said Henry Harteveldt, founder of travel industry consultancy Atmosphere Research Group and a former airline manager .

More than 1,100 Southwest Airlines flights, nearly a third of the Dallas-based airline’s schedule, were delayed on Monday while 44 were canceled. The airline said Sunday’s thunderstorms triggered Monday’s cancellations.

Spirit Airlines also canceled 304 flights on Monday – more than a third of its daily operations – followed by 165 flights a day earlier, according to FlightAware.

A spokesman said the disruptions were due to “operational challenges” caused by the weather. Airlines will often cancel flights to get the crews in place rather than continuing to delay flights.

“We are working around the clock to get back on track after a few travel interruptions at the weekend due to a number of operational challenges,” the airline said in a statement. “We understand how frustrating it is for our guests when plans change unexpectedly, and we are working to find solutions. We ask guests to actively monitor their emails and flight status before heading to the airport.”