Tornadoes have been recorded on all continents except Antarctica. They 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. Canada experiences the second most tornadoes. Ontario and the Prairie Provinces see the highest frequency. Other areas of the world that have frequent tornadoes include significant portions of Europe, South Africa, Philippines, Bangladesh, parts of Argentina, Uruguay, southern and southeastern Brazil, northern Mexico, eastern and western Australia, New Zealand, and far eastern Asia.Severe Weather 101-Tornadoes.www.nssl.noaa.gov. Retrieved 10 May 2026
Tornado reports in the U.S. have been officially collated since 1950. These reports have been gathered by the National Climatic Data Center (NCDC), based in Asheville, North Carolina. A tornado can be reported more than once, such as when a storm crosses a county line and reports are made from two counties. The severity of tornadoes is measured by the Enhanced Fujita Scale, which measures tornado intensity on a scale of EF0 to EF5 based on degree of destruction. The ratings are made after the tornado has dissipated and the damage trail is carefully studied by weather professionals. A series of continuous tornado outbreaks is known as a tornado outbreak sequence.
Necessary conditions Not every thunderstorm, supercell, squall line, or tropical cyclone will produce a tornado. The precisely right atmospheric conditions are required for the formation of even a weak tornado. Tornadoes can form in any month when conditions are favorable. 1,000 or more tornadoes a year are reported in the contiguous United States. The high frequency of tornadoes in North America is largely due to geography, as moisture from the Gulf of Mexico is easily advected into the midcontinent with few topographic barriers in the way. The Rocky Mountains block Pacific-sourced moisture and buckle the atmospheric flow, forcing the drier air to mid-levels of the troposphere. Downsloping winds off the Rockies force the formation of a dry line when the flow aloft is strong, while the Gulf of Mexico fuels abundant low-level moisture. This unique topography allows for frequent collisions of warm and cold air, the conditions that breed strong, long-lived storms throughout the year. This area extends into Canada, particularly Ontario and the Prairie Provinces. Tornadoes can also be triggered by hurricanes, although the tornadoes caused by hurricanes are often much weaker and harder to spot. Winter is the least common time for tornadoes to occur, since hurricane activity is virtually non-existent at this time, and it is more difficult for warm, moist maritime tropical air to take over the frigid Arctic air from Canada. Winter tornado occurrences are found mostly in the Gulf states (although there have been some notable exceptions).
South America's tornado corridor region is favorable for tornadoes and severe thunderstorms due to the large size of the Pampas Plain where the cold, dry air from Patagonia, the Andes, and Antarctica collides with warm, moist air from areas of Brazil, northern Argentina, and Paraguay.
Europe has some small "tornado alleys"—probably because of frontal collisions as in the south and east of England,Paul Rincon: UK, Holland top twister league. By Paul Rincon, BBC Science but also because Europe is partitioned by mountain ranges such as the Alps. The Po Valley (Pianura Padana) is one of the areas that experiences more tornado activity than elsewhere on the European continent. Located in the heart of Europe, between the Alps and the Apennines, the collision between cold and warm air here during the summer months easily permits the growth of very strong thunderstorms. The most frequent tornadoes occur in the eastern section of the Po Plains. Parts of Styria (Steiermark) in Austria may be a tornado alley, and this state has had at least three F3 tornadoes since 1900. F3 and perhaps one F4 tornado have also occurred as far north as Finland.
Geographical occurrences
The United States has by far the most tornadoes of any country. Many of these form in an area of the central United States known as Tornado Alley. This area extends into Canada, particularly the prairie provinces and Ontario. Activity in Canada, however, is less frequent and intense than that of the US. Strong tornadoes occur in northern Mexico. A large region of South America is also characterized by storms that reach the level of supercells and produce intense hailstorms, floods, and tornadoes during the spring, summer, and early fall. The region recently dubbed as the Tornado Corridor (South America) is considered the second largest in the world in terms of the formation of extreme weather events. It covers most of central Argentina, southern Paraguay, southeastern Brazil, and Uruguay.
Other areas of the world that have relatively frequent tornadoes include Germany, the Czech Republic, Slovakia, Italy, China, and the Philippines. Australia, France, Russia, areas of the Middle East, and Japan have a history of multiple damaging tornado events. Bangladesh and surrounding areas of eastern India suffer from a couple tornadoes annually of similar severity to stronger tornadoes in the US. These occur with a greater recurrence interval but over a smaller region. The annual human death toll from tornadoes in Bangladesh is estimated at 179 deaths per year, which is much greater than in the US. This is likely due to the density of population; poor quality of construction; lack of tornado safety knowledge; and lack of warnings—among other factors.
Number of tornadoes by region Various government agencies and published academic studies have kept track of the number of tornadoes based on geographic region.
RegionStudy conducted byYears of study# of tornadoesEuropeEuropean Severe Storms LaboratoryGerman Aerospace CenterKarlsruhe Institute of TechnologyMax Planck Institute for Nuclear PhysicsORF Austrian Broadcasting Corporation1966–202117,874ChileUniversity of ChileUniversity of O'HigginsCenter for Climate and Resilience ResearchDirección Meteorológica de ChileCEILAPUNIDEF1633–202251United StatesThomas P. Grazulis1680–19497,082AustraliaBureau of Meteorology1795–20191,326BengalCooperative Institute for Research in the AtmosphereColorado State UniversityNational Weather ServiceENSCO, Inc.1838–200387ArgentinaUniversity of Buenos Aires1889–2017330South AfricaZ. Muller with AfriWX1907–2022325New ZealandNational Institute of Water and Atmospheric Research1908–2019107BrazilState University of Ponta Grossa1975–2018581United StatesStorm Prediction Center1950–202265,057United StatesNational Centers for Environmental Information1950–202266,178BengalBangladesh University of Engineering and Technology1964–201325United StatesNational Weather Service1965–20226,874CanadaEnvironment and Climate Change Canada1980–20091,834ChinaTongji University2003–2019734MexicoNational Autonomous University of MexicoAutonomous University of ZacatecasInstituto Potosino de Investigación Científica y Tecnológica2007–2020350JapanJapan Meteorological Agency2007–2020531ChinaPeking University2007–2016983CanadaNorthern Tornadoes Project, Western University2017–2021375BrazilPREVOTS2018–2025524
By area Africa
Tornadoes do occur in extreme southern Africa (including the countries of South Africa, Lesotho, and Eswatini). In October 2011, two people were killed and nearly 200 were injured after a tornado formed, near Ficksburg in the Free State; more than 1,000 shacks and houses were flattened. There is also the seasonal incidence of tornadoes in the coast of Western Africa. These occur during the onset of the rainy season when tumultuous winds accompanied by sheets of rain as well as spectacular thunder and lightning batter the coast. The tornado generating storms were often welcomed by colonial settlers in the region since they dissipated extreme heat and humidity during the last days of the dry season . Tornadoes are often embedded in the African squall lines, but they damage crops, and diminish any beneficial effect of its rains.
Asia
Bangladesh and the eastern parts of India are very exposed to destructive tornadoes. Bangladesh, the Philippines, and Japan have the highest number of reported tornadoes in Asia. The single deadliest tornado ever recorded struck the Manikganj District of Bangladesh on 26 April 1989, killing an estimated 1,300 people, injuring 12,000, and leaving approximately 80,000 people homeless. Five other recorded tornadic events have killed more than 500 people in Bangladesh, most recently on 13 May 1996 when a tornado swept through the Jamalpur and Tangail districts, killing more than 600.
China occasionally experiences destructive tornadoes. Storms producing multiple tornadoes and hail struck a densely populated area of farms and factories near the city of Yancheng in Jiangsu province, about 800 kilometers (500 miles) south of Beijing, China. Throughout China, an estimated 100 tornadoes may occur per year with a few exceeding F2 in intensity, with activity most prevalent in eastern regions. During the period of 1948 until 2013, 4763 tornadoes were confirmed in China.
Europe
The UK has the most annual tornadoes per land area per year, at 0.14 per 1000 km2 (although these tornadoes are generally weak). Other European countries have a similar number of tornadoes per area. One notable tornado of recent years was the tornado that struck Birmingham, United Kingdom, in July 2005. A row of houses was destroyed, but no one was killed.
Europe as a whole has about 180 tornadoes per year. They are most common from June to August, especially in Central Europe and the Po Valley of Italy, and rarest from January to March. Strong tornadoes (F2, F3) do occur, but violent tornadoes (F4, F5) are quite rare - return rates for F4 events are a decade or more across the continent, and there has been no officially recorded F5s for the contemporary period in Europe. As in the US, tornadoes are far from evenly distributed. Since 1900, deadly tornadoes have occurred in Austria, Belgium, Cyprus, Czech Republic, Finland, France,North France tornado kills three – BBC News Germany, Italy,Corporate Report on the 8 July 2015 Tornado of Mira (VE), Italy essl.orgSurvey data essl.org Lithuania, Estonia, Malta, the Netherlands, Poland, Ukraine, Portugal, Romania, Russia, and the UK. The 1984 Ivanovo–Yaroslavl outbreak, with more than 400 fatalities and 213 injured, was the 20th century's deadliest tornado outbreak in Europe. It included at least two tornadoes with a rating of F4.
North America
Canada Canada annually experiences numerous tornadoes, although fewer than the United States. On average 62 are reported per year, but this number is expected to in fact be higher due to undetected tornadoes in large expanses of underpopulated areas. NOAA records a higher average of 100 per year in Canada. These storms cause tens of millions of dollars in damage. Most are weak F0 or F1 in intensity, but there are on average a few F2 or stronger that touch down each season.