Thursday evening thunder, lightning, and heavy rainfall lead to the cancelation of the Casting Crowns concert at the Unity Christian Music Festival in Muskegon.

At first festival organizers put the show in a weather delay, but soon realized storms approaching Muskegon were building in intensity.

"The safety of our guests are top priority," said Christopher VanOosterhout, Media and Marketing Director for the Unity Christian Music Festival.

Some Unity concerts have been held in rain. But it's the first time in the festivals 17 years a show has been canceled.

"We were able to speak with people at WZZM and they gave us some great advice about what to look for," said VanOosterhout. "Once the lighting continued we knew we had to evacuate Heritage Landing."

700-volunteers are trained to quickly direct guests off the festival grounds. VanOosterhout says around 15,000 people exited Heritage Landing in a calm manor with no issues.

As fans exited the park members of Casting Crowns recorded a performance from the safety of their dressing room.

It was posted on Unity's Facebook page with an explanation about why the show couldn't be held.

TobyMac is the headlining act Friday night. The festival finishes Saturday.

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