They give inclement weather warnings and will close the rides and pools down if it gets too close/bad.
They will shut down rides while rain, thunder, and/or lightning goes on. We were just there yesterday and they did it around 2:30 pm. They let you stick around in dry areas until bad weather passes.
Yesterday I was in the park when the bad weather started, they took us out of the attractions, even at one point they said that the park Ivan would close many people left but as we saw that it was moving the clouds and there were no rays we were required in areas safe. When the attractions reopened and the sun came up and we enjoyed the park almost 4 hours more.
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