Depending on "rain"... if it is without thunder and lightening.. then your safe. Some rides will stay open like the drop tower, the Cobra course and the Log Flumes. We were there 05-19-18 and it rained from 2pm to close and the rides and some restaurants were still open.
I would do the inside animal exhibits. And hopefully the teachers have ponchos so they can still ride. If not embrace it! Have fun even while wet!
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