By Craig Koplien Special to OnMilwaukee.com Published May 24, 2011 at 8:25 PM

Why are so many tornadoes hitting U.S. cities this year?

The answer is simply bad luck.

I know, not terribly scientific, but it’s true.

Most tornadoes don’t hit highly populated areas. However, it’s not because of the buildings or asphalt or cement. It’s because of simple geography. That is, in the parts of the U.S. where tornadoes are most common, there is a lot of rural, unpopulated area. When a tornado’s path does take it through a city or town, it’s the exception and not the rule.

Think about the Central and Southern Plains where tornadoes are most common. States like Nebraska, Kansas and Oklahoma have a tremendous amount of open area. It comes down to probability. There’s a much better chance that a tornado will drop out of a cloud and on to a wheat field in  Oklahoma than into a heavily-populated community.

Still, it does happen. Call it bad luck, fate or happenstance, there’s generally no rhyme or reason as to why a tornado rammed right through Joplin, Mo.  Sunday, instead of touching down in a relatively less-populated area about 20 miles to the south.

There has been one thing that has increased the probability of tornadoes hitting cities and towns this spring: The shear number of them.

Conditions have been unusually favorable for tornadoes several times this spring. Why this has happened is whole different blog and much less certain.

Why one tornado roars harmlessly through the middle of nowhere, while another barrels right down Main Street U.S.A., is simply a function of Mother Nature being cruelly random.

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Craig Koplien Special to OnMilwaukee.com

Craig is a meteorologist who was born and raised in Pewaukee. After getting a degree in Meteorology from the University of Wisconsin-Madison, he worked over 20 years on TV and radio in Milwaukee, Madison, Omaha, Nebraska and Kansas City, Missouri.

Craig spends most of his time trying to keep up with his bride and their three teenage daughters. Any time left over is spent with his other beloveds, the Packers, Brewers and Badgers.