I am hoping to hit a water park when we go next week, but notice on the forecast that the warmest day also has thunder storms forecasted. Do they close the water parks due to lightning when these happen? Or am I absolutely crazy to think of going to a waterpark when rain is forecast? 

Don't worry, we have a weather station and the park is shut down in plenty of time. I was there in the summer, with daily thunderstorms. Everyone has to get out of the water, but you don't have to leave. Usually the storm blows over in an hour!