The storms on Thursday morning caused an unusual cancellation. The Knoxville Recreation Center cancelled their Aquisize water fitness class, which takes place in their indoor pool. That pool is surrounded by large windows. Rec Center Director Brandon Nemmers says that while there’s never been an indoor pool lightning strike, they still take the necessary precautions, and evacuate the pool when lightning strikes. If there is no further lightning after 30 minutes, he says they open the pool back up.