Tornado Alley
States such as Missouri, Iowa, Minnesota, Wisconsin, Illinois, Indiana, and western Ohio are sometimes included in Tornado Alley. Research suggests that tornadoes are becoming more frequent in the northern parts of Tornado Alley where it reaches the Canadian prairies.
Canada Tornado Alley
In the Canadian Tornado Alley in Central/Western Canada, warm, humid air from the United States meets cool, dry air from Northern Canada and the Rocky Mountains. This creates an ideal environment for severe thunderstorms which could produce tornadoes. In the Great Lakes region towards the St. Lawrence River, severe thunderstorms which could produce tornadoes forms from warm, humid air from the United States and cooler air across the Great Lakes, these are triggered alongside lake-breeze fronts. The amount of precipitation in storms around the Great Lakes is normally more than the prairies as the warm temperatures and Great Lakes fuel the storms with heavy precipitation right from the lakes.