Tornadoes

Tornadoes are violent and rapidly rotating columns of air that form inside thunderstorms. They connect with the ground, via a funnel, to the cloud. Tornadoes typically last only a few minutes, but sometimes they can continue for more than an hour. They can also travel short distances (0.5 miles), but some can track upwards of 100 miles.

Since 1950, there have been more than 2,500 tornadoes recorded in Iowa. There have been six EF-5 (winds over 200 mph) observed in the state, and there have also been 45 EF-4 (166 - 200 mph) and 110 EF-3 (136 - 165 mph) rated tornadoes.

Source: Wikipedia