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.
1998 Eastern tornado outbreak
The 1998 Eastern Tornado Outbreak stands out, because it spawned an unusually high number of supercell thunderstorms, occurrences of damaging winds and hail, and tornadoes, in the central Appalachian Mountain area, where most residents were unaccustomed to experiencing such violent thunderstorms that are commonly believed to only occur in Tornado Alley in the central part of the United States.