Tens of thousands of flyers had their travel plans upended today after airlines canceled more than 1,100 flights for a second straight day because of thunderstorms hitting the East Coast.

The New York City area’s three major airports and Reagan National Airport outside Washington, D.C., recorded the most cancellations by this afternoon, according to tracking service FlightAware.

American Airlines scrubbed more than 200 flights, or 6% of its schedule. Republic Airways, which operates smaller planes for American Eagle, Delta Connection and United Express, also canceled more than 200 flights, about 20% of its schedule.

Another 3,700 flights were delayed by midafternoon.

Thunderstorms were causing delays averaging more than 90 minutes at LaGuardia Airport in New York and Newark Liberty International in New Jersey, according to the Federal Aviation Administration. The FAA said storms also could cause delays at major airports from Florida to Boston.

About 1,200 U.S. flights were canceled Thursday — 4.6% of all scheduled flights, and the highest number since July 25, according to FlightAware.

Travelers have been hit with widespread cancellations and delays this summer. Travel bounced back faster than expected — to about 88% of pre-pandemic levels in July — and airlines weren’t able to increase staffing fast enough. They have been cutting back on schedules in an attempt to make remaining flights more reliable.

Airlines flying in the U.S. had a bad June, canceling more than 21,000 flights or 2.7%, up from 1.8% in June 2019, before airlines pushed workers to quit during the pandemic. The airlines did better in July, however, canceling about 14,000 flights, or 1.8%.

Delays have been more persistent — above 23% in both June and July.