Instruct: Given a question, retrieve relevant passages that answer the question.
Query: What country has the most tornados?
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.[1] 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.[2] 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.[3][4]
Bangladesh is one of the countries with the highest frequency of tornadoes, behind the United States and Canada. Bangladesh has received other deadly tornadoes, but this particular storm was the worst in the country's history.
On May 30, 1998, the most destructive and second deadliest tornado in South Dakota history struck Spencer. It began as a large, dust-cloaked tornado NW of Farmer, South Dakota in Hanson County, concurrent with the demise of the "Fulton" tornado. Continuing toward the ESE, it struck several farmsteads before crossing the Hanson/McCook County line a half mile WNW of Spencer. At this time, the tornado was being observed by the OU Doppler on Wheels crew, whose mobile Doppler radar data showed up to 264 mph winds in the tornado a few tens of meters above ground level. The population of the town diminished soon after to less than half of what it was previous to the tornado, from 315 to 145 in April 1999, and has since hovered around that mark.
Tornadoes create different damage depending on how fast their wind speeds are. The Fujita Scale classifies a tornado by its wind speeds. For example, if the tornado's wind speeds are low, then it is classified as a F0 tornado. If the tornado's wind speeds are about 200 miles per hour or at 200 miles per hour, then it is classified as a F5 tornado. In the United States, tornadoes have been known to form at high and low intensities. The probability of a high intensity or violent tornado differs by location across the country. For example, due to the high frequency of tornadoes in the "Tornado Alley" area mentioned before, a more violent tornado would be more likely to form there due to the strength of the thunderstorms produced by the two bordering air masses. The states with the highest number of F5 and EF5 rated tornadoes since data was available in 1950 are Alabama and Oklahoma, each with seven tornadoes. Iowa, Kansas, and Texas each are tied for second most with six. The state with the highest number of F5 and EF5 tornadoes per square mile, however, was Iowa. The state with the most number of tornadoes classified as "violent", or F4 and F5, is Kentucky, and the state with the highest average intensity ranking for tornadoes is Alabama.
In the United States over 80 deaths and 1,500 injuries are associated with tornadoes each year. According to the National Oceanic Atmospheric Administration, most tornado deaths are caused by people not following instructions on what to do the right way. They also mention that some people are not even warned that a tornadic storm is coming, while others get a warning but do not believe that a tornado will hit their area. In 2012, 68 people were killed by tornadoes in the United States. Kentucky had the most fatalities, 22. Kentucky was followed by Indiana (13), Illinois (9), Missouri and Oklahoma (6), Ohio (4), Alabama and Tennessee (3), and Florida and Kansas (1).
Scattered tornadoes were reported across the US, but most were weak or remained over open country. However one tornado caused EF2 damage in the town of Bardwell, Kentucky. Another EF2 tornado destroyed airplane hangars near Cairo, Illinois. These later tornadoes were not part of the same weather system as the earlier tornadoes; they were part of a weather system that led to the 2011 Super Outbreak.
Thunderstorms are very common in Texas, especially the eastern and northern portion. Texas is part of the Tornado Alley section of the country. The state experiences the most tornadoes in the Union, an average of 139 a year. These strike most frequently in North Texas and the Panhandle.[4] Tornadoes in Texas generally occur in April, May, and June.[17]
There were 1,692 tornadoes confirmed in the United States in 2008, with 126 confirmed fatalities. This made 2008 the deadliest year in that country since 1998. Nine other fatalities have been reported elsewhere in the world: three in France, two each in Bangladesh and Poland and one each in Russia and China. With 1,692 confirmed tornadoes, 2008 ranked as the third most active US tornado season on record, only 2011 and 2004 have had more tornadoes confirmed with 1,697 and 1,817, respectively. The US state of Kansas received the most tornadoes in the United States in 2008 with 187.
This page documents notable tornadoes and tornado outbreaks worldwide in 1973, but mostly features events in the United States. According to tornado researcher Thomas P. Grazulis, documentation of tornadoes outside the United States was historically less exhaustive, owing to the lack of monitors in many nations and, in some cases, to internal political controls on public information. Most countries only recorded tornadoes that produced severe damage or loss of life. Consequently, available documentation in 1973 mainly covered the United States. On average, most recorded tornadoes, including the vast majority of significant—F2 or stronger—tornadoes, form in the U.S., although as many as 500 may take place internationally. Some locations, like Bangladesh, are as prone to violent tornadoes as the U.S., meaning F4 or greater events on the Fujita scale.
Though Windsor had CKLW as a radio station from Detroit, Michigan, there were no records kept from them. CBC Toronto was the only radio station that has kept their archives for the reports on this event. CBC Archives helps to explain what happened in Windsor the day after on Windsor, Ont. struck by tornado in 1946. The report explains what happened, how many were killed, how citizens feel and even what was stolen and who came out to help. In addition to this report, there were many reports to explain how the tornado was formed for this tornado. The reports also hold onto interviews from people who viewed the tornado first hand.
More tornadoes occur in Texas than in any other US state. The state which has the highest number of tornadoes per unit area is Florida, although most of the tornadoes in Florida are weak tornadoes of EF0 or EF1 intensity. A number of Florida's tornadoes occur along the edge of hurricanes that strike the state. The state with the highest number of strong tornadoes per unit area is Oklahoma. The neighboring state of Kansas is also a particularly notorious tornado state. It records the most EF4 and EF5 tornadoes in the country.
This page lists tornadoes and tornado outbreaks which have touched down in Canada prior to the 21st century. On average, there are around 80 confirmed and unconfirmed tornadoes that touch down in Canada each year, with most occurring in Southern Ontario, the southern Canadian Prairies and southern Quebec. Canada ranks as the country with the second most tornadoes per year, after the US. The most common types are F0 to F2 in damage intensity level and usually result in minor structural damage to barns, wood fences, roof shingles, chimneys, uprooted or snapped tree limbs and downed power lines. Fewer than 5% of tornadoes in Canada are rated F3 or higher in intensity, where wind speeds are in excess of . Prior to April 1, 2013, Canada used a slightly modified Fujita scale, and as of that date the Enhanced Fujita scale, again slightly modified, was put into use to rate tornado intensity, based on the damage to buildings and vegetation.
While it is unlikely that the 1979 storm was as powerful as the 1946 Windsor-Tecumseh, Ontario tornado (where it has been speculated that F5 damage took place), the most glaring difference was that of path width. Whereas the damage paths of the 1946, 1953, and 1985 tornadoes remained under one kilometre, the Woodstock one was more massive in size. In some cases its width approached one mile, likely making it one of the largest tornadoes documented in Canada alongside the July 1987 Edmonton Tornado. Environment Canada places the 1979 Woodstock tornado as the eleventh worst in the country's history.http://www.simcoereformer.ca/2009/08/26/memories-whirl-of-tornado-79
Tornadoes occur frequently in Alabama during the spring and fall months, these tornadoes can be devastating and even deadly.– these are common throughout the state, although the peak season for tornadoes varies from the northern to southern parts of the state. Alabama, along with Kansas, has the most reported F5/EF5 tornadoes than any other state – according to statistics from the National Climatic Data Center for the period January 1, 1950, to October 31, 2006. An F5 tornado is the most powerful of its kind. Several long – tracked F5 tornadoes have contributed to Alabama reporting more tornado fatalities than any other state except for Texas and Mississippi. The Super Outbreaks of April 1974 and April 2011 both badly affected Alabama. The northern part of the state – along the Tennessee Valley – is one of the areas in the US most vulnerable to violent tornadoes . The area of Alabama and Mississippi most affected by tornadoes is sometimes referred to as Dixie Alley, as distinct from the Tornado Alley of the Southern Plains. Alabama is one of the few places in the world that has a secondary tornado season (November and December) along with the spring severe weather season.
As with most of the northeastern United States, the number of tornadoes peaks in the summer months, normally in July or August. Hartford County has had the most tornadoes in the state, although since 1950 Litchfield County has reported the most tornadoes. Several areas have been struck more than once, and Waterbury has been struck by no less than four tornadoes since 1955.
The Manitou Beach region was devastated by two F4 tornadoes during the April 11, 1965 Palm Sunday Tornado Outbreak. Most of what was destroyed was rebuilt, including the dance hall and two churches. Over the course of the past five decades, the resort has had few reminders of the tornado.
The most unusual tornado event of the year occurred on August 19. Seven tornadoes were recorded in Minnesota that day, including one that touched down in Minneapolis. What made this day unusual is that a unique atmospheric setup allowed several of the tornadoes to be spawned from rain showers where no lightning was present.
Although the most damaging tornado of the outbreak sequence occurred in Greensburg on the 4th, twenty-five tornadoes were confirmed that day. That number exploded to 84 the following day (May 5), with many tornadoes near the affected area from the previous night. Most were in open country, but there were injuries in at least two spots in Kansas, and one death reported near a county lake in Ottawa County. 14 more tornadoes were confirmed on May 6th in the region before the outbreak finally ended.
It is internationally recognised that the United Kingdom has a higher incidence of tornadoes, measured by unit area of land, than any other country in the world. Dr T. Theodore Fujita (inventor of the Fujita scale), an American meteorologist, was the first to recognise the UK as the top site for tornadoes in 1973. The United Kingdom has at least 33 tornadoes per year, more than any other country in the world relative to its land area. Although most tornadoes are weak, there are occasional destructive events, for example, the Birmingham tornado of 2005 and the London tornado of 2006. Both registered F2 on the Fujita scale and both caused significant damage and injury. The largest ever recorded was thought to have been an F4, again in London in 1091. The most deadly occurred on 28 December 1879. All 74 lives were lost when a passenger train plunged from the Tay Bridge (Tayside) into the Tay Estuary, when the middle section of the bridge collapsed. Although the bridge was poorly constructed and had already been weakened in earlier gales (including the pre-existing winds at the time of the tragedy), the ultimate failure is believed to have been caused by two or three waterspouts which were sighted close to the bridge immediately before the accident. A tornado also developed in London on 3 July 2007.
The UK also holds the title for the highest known 'outbreak' of tornadoes outside of the United States. The largest tornado outbreak in Britain is also the largest tornado outbreak known anywhere in Europe. On 23 November 1981, 105 tornadoes were spawned by a cold front in the space of 5.25 hours. Excepting Derbyshire, every county in a triangular area from Gwynedd to Humberside to Essex was hit by at least one tornado, while Norfolk was hit by at least 13. Very fortunately most tornadoes were short-lived and also weak (the strongest was around T5 on the TORRO Tornado Scale) and no deaths occurred.
The United States averaged 1,274 tornadoes per year in the last decade while Canada reports nearly 100 annually (largely in the southern regions). However, the UK has most tornadoes per area per year, 0.14 per 1000km², although these tornadoes are generally weak, and many other European countries have a similar number of tornadoes per area.[1]
In what was apparently an intense tornado outbreak sequence, other major tornado outbreaks occurred on May 15, May 17, and May 24–25, with other smaller outbreaks during the month as well. The middle to end of May was extremely active but sparse records preclude knowing much detail. Tom Grazulis has stated that the week of May 24–28 was "perhaps the most violent single week of tornado activity in US history".
There are several scales for rating the strength of tornadoes. The Fujita scale rates tornadoes by damage caused and has been replaced in some countries by the updated Enhanced Fujita Scale. An F0 or EF0 tornado, the weakest category, damages trees, but not substantial structures. An F5 or EF5 tornado, the strongest category, rips buildings off their foundations and can deform large skyscrapers. The similar TORRO scale ranges from a T0 for extremely weak tornadoes to T11 for the most powerful known tornadoes.[9] Doppler radar data, photogrammetry, and ground swirl patterns (trochoidal marks) may also be analyzed to determine intensity and assign a rating.[10][11]
Oklahoma City has a very active severe weather season from March through June, especially during April and May. Being in the center of what is colloquially referred to as Tornado Alley, it is prone to especially frequent and severe tornadoes, as well as very severe hailstorms and occasional derechoes. Tornadoes have occurred in every month of the year and a secondary smaller peak also occurs during autumn, especially October. The Oklahoma City metropolitan area is one of the most tornado-prone major cities in the world, with about 150 tornadoes striking within the city limits since 1890. Since the time weather records have been kept, Oklahoma City has been struck by thirteen violent tornadoes, eleven F/EF4s and two F/EF5s.
The United Kingdom has the highest incidence of tornadoes, measured by unit area of land, than any other country in the world.[86] Unsettled conditions and weather fronts transverse the Islands at all times of the years and are responsible for spawning the tornadoes, which consequently form at all times of the year. The United Kingdom has at least 34 tornadoes per year and possibly as many as 50,[87] more than any other country in the world relative to its land area. Most tornadoes in the United Kingdom are weak, but they are occasionally destructive. For example, the Birmingham tornado of 2005 and the London tornado of 2006 both registered F2 on the Fujita scale and both caused significant damage and injury.[88]
The Netherlands has the highest average number of recorded tornadoes per area of any country in the world (more than 20, or 0.0005 per km), annually), followed by the UK (around 33, or 0.0001 per km), per year), but most are small and cause minor damage. In absolute number of events, ignoring area, the UK experiences more tornadoes than any other European country, excluding waterspouts. Europe uses its own tornado scale, known as the TORRO scale, which ranges from a T0 for extremely weak tornadoes to T11 for the most powerful known tornadoes.