Kings of Leon performs onstage at the 2014 Budweiser Made In America Festival at Benjamin Franklin Parkway on August 30, 2014 in Philadelphia, PA.

Kings of Leon's headlining set at the 2015 Firefly Music Festival was cancelled due to inclement weather, as a lightning storm approached The Woodlands in Dover, Delaware on Saturday night (June 20) and the festival grounds were fully evacuated.

The announcement was made minutes after the Tennessee rock group were supposed to take the Firefly main stage at 9:45 PM on Saturday night. "Dangerous, inclement weather is coming," an announcement went over the main stage PA system. "Please clear the festival site."

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The lightning storm soon turned to rain as thousands of festival goers were herded out of the grounds. Campers were encouraged to take down all pop-up tents and poles, and remain in their vehicles during the storm.

Kings of Leon were originally supposed to perform at 10:30 PM on Saturday night, and the group's set was pushed forward 45 minutes due to weather concerns. Kid Cudi's performance on the Backyard Stage was cut short after 20 minutes, and Steve Aoki's late-night set was also cancelled.

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In 2013, torrential rain prevented Kings of Leon from taking the stage at the Governors Ball Music Festival for a Friday night headlining set. The band made up for the cancellation by performing on Saturday afternoon at the New York festival.

Firefly has yet to announce if Kings of Leon or any other Saturday night performer will play on the set's final day on Sunday (June 21). The Killers are slated to headline on Sunday night.