I was driving across Texas in my younger days and crossed paths with a tornado on Hwy. 10 east of Houston. My buddy and I didn't know any better so we stopped under a bridge and climbed up onto the girders. The twister crossed the interstate just ahead of the bridge. We survived without injury but there was all kinds of trash flying up under the bridge. I can see how that could be a hazard if the debris were larger than what we encountered. We got plenty nasty from all the road grime that went airborne, not to mention the bird poop we were lying in. I don't think I would repeat that, hope I don't have to, but it made sense at the time. Here in Georgia we get pop up twisters that you can't see coming until they are right on top of us. Had one 4 years ago on Mothers Day that took out about a dozen grand old oak trees at my house. Thankfully none hit the house and no one was injured.