I'm surprised this hasn't got a thread already. At first I was all like "When will people learn that building your homes out of fucking wood is no good when storms tear through" but then I saw all the metal and stone buildings reduced to rubble and I was like "dang". http://youtu.be/XMF22_MEMJU http://youtu.be/dCbhnPfEvF8 Shit's fucked up.
You're pretty much fucked if a powerful tornado is heading your way. Even concrete structures aren't necessarily safe. Your best chance for survival is to get underground. In this case, some of the tornadoes were a mile in diameter. And they approach so fast, you can't outrun or even out drive them. All you can do is try to find a basement and ride it out. Also, they're putting the death toll now at 91 people.
I saw twister. All you have to do is tie yourself to a flimsy water pipe and you can survive an F5 no problem.