Several years ago, I was driving my little Saturn back from Fredericksburg to Fort Worth when a storm whipped up and caught me on I-35 (back before I learned about 287). I heard a couple of hailstones ping off my hood/roof and stopped under the next overpass where I spent the next several minutes hiding in the base of the girders with some other folks, until the worst of it passed. Guess we were lucky it didn’t reach tornado level. Otherwise, I can’t really think of where else we could have gone, because it sure was flat as all get out around there.
A concrete and steel overpass ain’t going nowhere. Can there be a wind tunnel effect? Yes. Is there anyplace else to go? Most often not.