U.S Tornado Distribution

The U.S. Tornado map displays all recorded tornadoes observed between the years of 1950 to 2009.

This map illustrates the "Tornado Alley" located in the middle of the continent ranging from the Gulf of Mexico in the south to the southern section of Minnesota in the north. This area has such a high frequency of tornadoes because of the meeting of cP (continental polar) air mass from the north and mT (maritime tropical) air mass from the south. The meeting of these contrasting air masses gives the U.S. more tornadoes than anywhere else in the world.

The tornadoes in this map are displayed by their destruction power. A more powerful tornado with greater wind speeds will appear thicker than a weaker tornado. As you can see, the majority of tornadoes that occur in the U.S. are relatively weak.