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.
Dixie Alley
Although tornadoes are less frequent in these states than they are in the southern Plains, the southeastern states have had more tornado-related deaths than any of the Plains states (excluding Texas). This is in part due to the relatively high number of strong/violent long tracked tornadoes and higher population density of this region, as well as the Southern United States having the highest percentage of manufactured homes in the US, where 63% of the overall tornado-related fatalities occur. According to the National Climatic Data Center, for the period January 1, 1950 – October 31, 2006, Alabama and Kansas received the largest amount of F5 tornadoes. Complicating matters is that tornadoes are rarely visible in this area, as they are more likely to be rain-wrapped, embedded in shafts of heavy rain, and that the hilly topography and heavily forested landscape makes them difficult to see.