In most of the reporting and stories about the tornado that hit Moore, OK, last week, someone asks why there aren't more tornado shelters. Most people answer that although the area is called "Tornado Alley", the chance of a tornado actually coming close is so small it's not worth the cost. It's big country there. It's sorta like getting hit by lightning.
In all those stories and reporting, no one to my knowledge has mentioned the 1999 tornado that hit Moore. It was an F5 (the highest rating), a mile to two miles wide, killed 41 people and injured almost 500, hit 8,132 homes, 1,041 apartments, 260 businesses, 11 public buildings and seven churches, and has the distinction of the fastest winds ever recorded for a tornado, at about 300 mph.
That sounds like the topography around Moore is conducive to funneling funnels right through there, maybe?
Maybe a few dollars worth of root cellar would be a good investment after all.