• Southwest Airlines briefly paused its departures on Tuesday after reporting technical problems.
• As of shortly after 11 a.m. ET, more than 1,500 flights, or 36% of Southwest’s schedule, were delayed, according to flight-tracking site FlightAware.
• Southwest had a meltdown over the year-end holidays, which drove thousands of flight cancellations and resulted in an $800 million pretax hit for the fourth quarter.

Southwest Airlines briefly paused its departures on Tuesday after reporting technical problems, delaying flights around the country.

The Federal Aviation Administration said the ground stop had been lifted, but many flights were still delayed. As of shortly after 11 a.m. ET, more than 1,500 flights, or 36% of Southwest’s schedule, were delayed, according to flight-tracking site FlightAware.

“We’re aware of intermittent issues with our website and mobile app, but we’re working hard in making sure our Customers have full capabilities on our site,” read a response post from Southwest’s Twitter account. “Updates will be communicated when the site is fully functional. Please continue to hang in there with us!”

The airline didn’t immediately comment further. Airlines or the FAA will occasionally pause departures, particularly at certain airports, to avoid bottlenecks for parking on the ground.

Southwest had a meltdown over the year-end holidays, which drove thousands of flight cancellations and resulted in an $800 million pretax hit for the fourth quarter. The airline upgraded scheduling software that couldn’t handle numerous changes to crew assignments during severe winter weather late last year.

The issues Tuesday did not appear to be related to that software.

Southwest reports first-quarter results on April 27 before the market opens.

As of Tuesday morning, Miami International Airport had 59 delays for all flights including Southwest. Fort Lauderdale-Hollywood International Airport had 120 total delays.