Yes! :) You may not be able to enjoy the playground or other features around the cave as much, but we visited yesterday after 2 days of rain and the cave was perfectly fine. One of our kids asked if rain was ever a problem with the cave flooding and the tour guide explained that rain very rarely affects the cave (she could only think of one time and that was a record breaking year for rain).
I think it's safe to visit in the rain. You might get a little wet walking into the entrance of the cave.
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