The Port Authority is warning travelers to expect delays and cancellations at LaGuardia Airport due to a sinkhole discovered near a runway on Wednesday morning.

The airport said in an announcement on social media that the runway was immediately shut down after the sinkhole was discovered around 11 a.m. and emergency construction crews were working to determine the cause and make repairs.

LaGuardia was leading FlightAware.com's "Misery Map" of delays and cancellations on Wednesday afternoon, with 270 delays and 197 cancellations in or out of the airport.

Notices on LaGuardia's website also warned of potential delays due to Wednesday's weather conditions, which included brutal heat and expected thunderstorms.

Average delays were under an hour as of about 4:30 p.m.