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.
Canada Tornado Alley
Although the official boundaries of the Canadian Tornado Alleys are not clearly defined, its core extends from Central Alberta through Saskatchewan, Southern Manitoba and Northwestern Ontario. A second tornado alley extends from Michigan to Central Ontario and from Central Ontario to Southwestern Quebec. The Canadian Prairies are often considered part of the United States tornado alley.