Smart people who live in tornado alley, especially in towns that have been hit, have a storm cellar.
That is cover. A trailer is camouflage. One will keep the projectiles from hitting you, the other won’t. I stated it depends on the circumstance and specifically stated that without cover the smart move is to travel at a high rate of speed perpendicular to the tornado track. I know that’s not for everybody though and certainly what I am saying here is in no way meant to criticize any poor soul caught up in that storm. My heart and my prayers go out to them all. They are fellow Americans in bad times. God bless them.