If you were in the parks and a tornado warning was issued for that area where would be the very best locations to be at for cover and the very worst locations to be at in the parks?
As in any other emergency, listen to Cast Member instructions. They’re the ones who will know the best location in any given area. General tornado instructions say lowest level, away from windows & doors.
I expect if there's a tornado Watch, nothing really happens. But if there's an actual tornado Warning (meaning a funnel has been spotted in the area on or near the ground), they would be doing much more than batting their eyes. For the rare occasions that's happened at WDW, there are reports of alarms going off throughout the resort, and guests instructed to get to a safer area for their protection - be it the restrooms or strong buildings in the parks or the lower floors in the hotels. In a tornado warning situation, things move very quickly to get folks to safety.