Tornado climatology
Tornadoes have been recorded on all continents except Antarctica and are most common in the middle latitudes where conditions are often favorable for convective storm development. The United States has the most tornadoes of any country, as well as the strongest and most violent tornadoes. A large portion of these tornadoes form in an area of the central United States popularly known as Tornado Alley. Other areas of the world that have frequent tornadoes include significant portions of Europe, South Africa, Philippines, Bangladesh, parts of Argentina, Uruguay, and southern and southeast Brazil, northern Mexico, New Zealand, and far eastern Asia.
List of Canadian tornadoes and tornado outbreaks
For a variety of reasons, such as Canada's lower population density and generally stronger housing construction due to the colder climate, Canadian tornadoes have historically caused far fewer fatalities than tornadoes in the United States. The deadliest tornado in Canadian history, the Regina Cyclone of June 30, 1912, does not even rank in the top 25 when compared to American tornado fatalities. Urban centres are not immune from the threat of severe tornadoes. Nine medium to large size Canadian cities have been hit by significant strength tornadoes (F3 or higher), which caused large-scale damage and fatalities: Regina (1912); Windsor (1946 and 1974); Sarnia (1953); Sudbury (1970); Woodstock (1979); London (1984); Barrie (1985); Edmonton (1987) Goderich (2011), Alonsa, Manitoba (2018) and Ottawa-Gatineau (2018). All figures for damages are in Canadian dollars.