Southwest Airlines canceled 500 flights, 15% of its schedule, Tuesday as it struggled with connectivity issues, a day after technical problem with a weather data supplier delayed hundreds of flights.
The Federal Aviation Administration briefly issued a nationwide ground stop for Southwest, which prevents its flights from taking off to avoid overwhelming destinations.
More than 1,690 Southwest flights were delayed on Tuesday, close to half of the carrier’s schedule, according to flight tracking site FlightAware. The airline said operations were returning to normal by Tuesday afternoon.
“Southwest is in the process of resuming normal operations after a brief pause in our flight activity resulting from intermittent performance issues with our network connectivity Tuesday afternoon,” Southwest spokesman Chris Mainz said in a statement. “Our Teams are working quickly to minimize flight disruptions and Customer impact. We appreciate our Customers’ patience as we work to get them to their destinations.”
Southwest said it is investigating the issue and doesn’t have reason to believe it’s connected to Monday’s problem.
Denver International Airport earlier tweeted that Southwest was having a “network connectivity issue” and warned travelers that flight delays are likely.
On Monday, 1,541 Southwest flights, about 41% of its schedule, were delayed, according to FlightAware.
The airline said that its operations on were disrupted Monday evening after its “third-party weather provider experienced intermittent performance issues” but told employees earlier Tuesday that it was in “relatively good shape” as operations resumed.
The issue occurred just as airlines like Southwest are flying an increasing number of travelers as demand rebounds from the coronavirus pandemic.
Carriers are grappling with a surge in customers along with employee reductions after they offered buyouts and other packages to cut costs in the pandemic. Southwest, Delta Air Lines and American Airlines, for example, have warned travelers about long hold times for customer service and encouraged them to use self-service options.
While Southwest’s issue Tuesday appeared to have only briefly impacted its systems, longer-lasting technology issues or outages can be costly. Delta estimated an August 2016 data center outage that led to about 2,300 cancelations over three days cost it about $150 million in pretax income that quarter.
This article originally appeared on CNBC