Thursday’s snowfall caused hundreds of flights to be delayed at Denver International Airport, according to FlightAware, a tracking company.

As of 11 p.m. Thursday, FlightAware reported 924 delayed flights at DIA and 34 flight cancelations.

FlightAware said departure delay times are averaging about 30 minutes, with the delay times decreasing.

Southwest has delayed 290 flights so far, making up 55% of its total flights for the day. SkyWest has delayed 218 of its flights, which represented 66% of its total number of flights today. Southwest canceled 28 flights and Skywest canceled 5.

The airport area is expected to see 1 to 3 total inches of snow during the day, according to the National Weather Service. Tonight, the forecast predicts 2 to 4 new inches of snow.

DIA takes preventative measures for snowfall. The airport says it has 600 trained snow removal personnel, with crews deployed at the start of a snowfall and kept in place 24/7 for the entire weather event.

The airport says it also has about 364 pieces of airside snow removal equipment. The airport’s multi-function equipment and other snow management allows workers to clear a runway in under 15 minutes.

Passengers can see updated delay information on FlightAware’s website.