(CNN) -- Denver International Airport officials assessed aircraft damage Thursday, one day after a powerful storm stranded 1,000 passengers overnight and pelted planes with penny-sized hail, officials said.
The storm dinged more than 40 aircraft and caused wind gusts close to 60 mph, said airport spokeswoman Laura Coale.
The National Weather Service issued a severe thunderstorm warning about 9 p.m. Wednesday, and that lasted about an hour and included a hailstorm that lasted for about 15 minutes.
Although most airlines reported significant hail damage, Frontier, Southwest and United Airlines bore the brunt of it, Coale said.
Marilee McInnis, spokeswoman for Southwest Airlines, confirmed three aircraft were damaged in the storm. One was back in service and the other two were undergoing further inspection, McInnis said Thursday.
Frontier Airlines canceled 20 flights Thursday, removing damaged aircraft from service, said spokesman Peter Kowalchuk.
Cancellations were increasing for United, which nixed 38 departures and 56 arrivals, Coale said.
No facility damage was reported, Coale said.
CNN's Elwyn Lopez contributed to this report.