A ground delay at Denver International Airport derailed hundreds of flights Thursday as afternoon thunderstorms swept across the state, threatening flash floods.
As of 3 p.m. Thursday, 440 flights headed in and out of DIA had been delayed and seven were canceled, according to flight tracking data from FlightAware.
The Federal Aviation Administration issued a weather-based ground delay just after 2 p.m. Thursday that was expected to last through 10 p.m., according to the agency.
At 3 p.m., the traffic management program was delaying flights by an average of 1 hour and 17 minutes, federal aviation officials said.
Southwest delayed the most flights at 214, and 102 United flights failed to leave the gate on time, according to FlightAware.
Other Thursday afternoon delays included 68 SkyWest flights, 17 Frontier flights, 10 Key Lime Air flights, nine American Airlines flights, eight Delta flights and eight Alaska Airlines flights. Three other airlines delayed between one and five flights.
United canceled the most flights on Thursday, removing five flights from its roster, and Southwest canceled two.
This is a developing story and will be updated.
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