Tornado Alley
It has also been asserted that there are numerous Tornado Alleys. In addition to the Texas/Oklahoma/Kansas core, such areas include the Upper Midwest, the lower Ohio Valley, the Tennessee Valley and the lower Mississippi valley. Some studies suggest that there are also smaller tornado alleys located across the United States.
South Dakota
South Dakota summers bring frequent, sometimes severe, thunderstorms with high winds, thunder, and hail. The state's eastern part is often considered part of Tornado Alley, and South Dakota experiences an average of 30 tornadoes each year. Severe blizzards and ice storms occur often during winter.