There are lots of folk legends concerning tornadoes, and most of them are completely untrue.
There is, however, one bit of evidence that seems to support at least one of the old tales,
“Tornadoes Never Hit Mountains”. Mountain ranges tend to disrupt the flow of air that makes tornadoes and statistics show that the mountainous ranges of Virginia have fewer tornadoes than the flat regions of the state.
So, to say that mountains stop tornadoes isn’t correct, but to say mountains have fewer tornadoes is true.