This is a list of government or academic case studies on individual tornadoes or tornado outbreaks which occurred during the 2020s. A case study is an in-depth analysis which focuses on a single event, several events, and/or a specific aspect of an event. [1] [2]
Case studies published by academia are included in this list. As part of the United States National Weather Service's (NWS) and Environment and Climate Change Canada's (ECCC) official duties, they are required to conduct a damage survey on every tornado in the United States and Canada. For this reason, only publications by the NWS and ECCC beyond a standard damage survey are included as, on average, over 1,200 tornadoes occur annually in the two countries together. Tornado records in Europe are kept by the European Severe Storms Laboratory (ESSL) in the European Severe Weather Database. For this reason, only publications by ESSL outside of the database are included.
| Tornado(es) | Max rating | Summary |
|---|---|---|
| 2020 Nashville tornado outbreak | N/A | Researchers with Mississippi State University and Indiana University–Purdue University Indianapolis published a case study on how TV stations covered the outbreak. [3] |
| 2020 Nashville tornado | EF3 | Researchers with the University of Oklahoma’s CIWRO, the National Severe Storms Laboratory, the University of Maryland, College Park published a case study on the short-term forecasting of this nocturnal tornado. [4] |
| 2020 Cookeville tornado | EF4 | Researchers with the University of Oklahoma’s CIWRO, the National Severe Storms Laboratory, the University of Maryland, College Park published a case study on the short-term forecasting of this nocturnal tornado. [4] |
| Researchers from the University of Oklahoma, Auburn University, and University of Illinois Urbana-Champaign conducted a case study on survivors of the tornado can help future forensic engineering. [5] | ||
| 2020 Easter tornado outbreak | N/A | Researchers with the University of Oklahoma’s CIWRO, the National Severe Storms Laboratory, and National Weather Service forecasting office in Columbia, South Carolina, published a case study on the forecasting of and the aftermath of the second day of the 2020 Easter tornado outbreak, more commonly known as the Central Savannah River outbreak. [6] |
| Researchers with Mississippi State University and Indiana University–Purdue University Indianapolis published a case study on how TV stations covered the outbreak. [3] | ||
| 2020 Scarth tornado | CEF3 | Researchers with the University of Western Ontario's Northern Tornado Project conducted a case study on this tornado, in which, they estimated the tornado had winds of at least 110–119 metres per second (250–270 mph; 400–430 km/h) based on an analysis of an SUV and a truck thrown by the tornado 50 metres (55 yd) and 100 metres (110 yd) respectively. [7] |
| 2021 South Moravia tornado | IF4 | Researchers with the European Severe Storms Laboratory, Czech Hydrometeorological Institute, Slovak Hydrometeorological Institute, Meteopress, Comenius University, and Charles University published a detailed damage survey of the tornado using the brand new International Fujita scale (IF-scale). [8] |
| A case study by Simona Hoskovcová, Martina Wolf Čapková, and Štěpán Vymětalon on the "phycological crisis" created by the tornado. [9] | ||
| Researchers with Palacký University Olomouc and the Police Academy of the Czech Republic in Prague published a case study on the tornado. [10] | ||
| Researchers with the Brno University of Technology published a case study on the damage caused by the tornado. [11] | ||
| Researchers with the European Severe Storms Laboratory, Czech Hydrometeorological Institute, Charles University , Meteopress, Slovak Hydrometeorological Institute, Commenius University, Geosphere, Austrocontrol, and Brno University of Technology, published a detailed damage survey of the tornado through the American Meteorological Society using a new version of the International Fujita scale. [12] | ||
| Tornado outbreak of July 11–13, 2021 | N/A | Researchers with Peking University, China Meteorological Administration Tornado Key Laboratory, Foshan Tornado Research Center, Southern Marine Science and Engineering Guangdong Laboratory, and the China Meteorological Administration published a case study on the tornado outbreak, which was the second-ever record tornado outbreak in Chinese history. [13] |
| 2021 Quad-State Supercell | N/A | Researchers with the University of Nebraska–Lincoln published a detailed case study on the polarimetric radar observations obtained on the 2021 Quad-State Supercell, which produced 11 tornadoes, including two long-track, violent EF4 tornadoes. [14] |
| 2021 Western Kentucky tornado | EF4 | A case study by Rebecca Freihaut with the University of Central Florida on how the residents of Mayfield, Kentucky recovered after the tornado. [15] |
| A case study by researchers from Pennsylvania State University on how historic masonry structures in Mayfield, Kentucky preformed during the tornado. [16] | ||
| A detailed damage survey and analysis of part of the tornado's track, focusing mainly on Mayfield, Kentucky published by Timothy Marshall, a meteorologist, structural and forensic engineer; Zachary B. Wienhoff, with Haag Engineering Company; Christine L. Wielgos, a meteorologist at the National Weather Service of Paducah; and Brian E. Smith, a meteorologist at the National Weather Service of Omaha. In their conclusion, the researchers state, “the tornado damage rating might have been higher had more wind resistant structures been encountered. Also, the fast forward speed of the tornado had little ‘dwell’ time of strong winds over a building and thus, the damage likely would have been more severe if the tornado were slower.” [17] | ||
| 2022 Arabi–New Orleans tornado | EF3 | Researchers with Auburn University, Florida International University, Pennsylvania State University, Louisiana State University, University of South Alabama, University of Illinois Urbana-Champaign, University of Kentucky, and CoreLogic, published an academic case study on how hurricane-resistant houses performed during the tornado. [18] |
| 2023 Rolling Fork–Silver City tornado | EF4 | The National Weather Service offices in Jackson, Mississippi and Nashville, Tennessee, along with the National Severe Storms Laboratory and the University of Oklahoma's CIWRO publish a joint damage survey and analysis on the tornado. [19] |
| A case study from researchers with Nanyang Technological University and the University of California on how soil moisture observations led to discrepancies being discovered on the tornado’s track vs spotter confirmations vs official damage assessments from the National Weather Service. [20] | ||
| A case study by researchers from the Microsoft AI for Good Research Lab, Microsoft Philanthropies, and the American Red Cross on how rapid building damage assessment was conducted following the tornado. [21] | ||
| A case study by researchers with the University of Oklahoma's CIWRO, the National Severe Storms Laboratory, and the Mississippi/Alabama Sea Grant on the tornado. [22] | ||
| 2023 Black Hawk–Winona tornado | EF3 | The National Weather Service offices in Jackson, Mississippi and Nashville, Tennessee, along with the National Severe Storms Laboratory and the University of Oklahoma's CIWRO publish a joint damage survey and analysis on the tornado. [19] |
| A case study by researchers with the University of Oklahoma's CIWRO, the National Severe Storms Laboratory, and the Mississippi/Alabama Sea Grant on the tornado. [22] | ||
| 2023 New Wren–Amory tornado | EF3 | The National Weather Service offices in Jackson, Mississippi and Nashville, Tennessee, along with the National Severe Storms Laboratory and the University of Oklahoma's CIWRO publish a joint damage survey and analysis on the tornado. [19] |
| Researchers with the Oak Ridge National Laboratory conducted a case study and detailed damage survey of the tornado. [23] | ||
| A case study by researchers with the University of Oklahoma's CIWRO, the National Severe Storms Laboratory, and the Mississippi/Alabama Sea Grant on the tornado. [22] | ||
| Tornado outbreak of April 19–20, 2023 | N/A | The National Weather Service office in Norman, Oklahoma published a detailed damage survey and analysis for tornadoes during the outbreak. [24] |
| 2023 Didsbury tornado | CEF4 | Researchers with the University of Western Ontario's Northern Tornado Project conducted a case study on this tornado, in which, they estimated the tornado had winds at least 119 metres per second (270 mph; 430 km/h) based on an analysis of a New Holland TR86 combine harvester that was thrown 100 metres (110 yd) by the tornado. [7] |
| 2023 Jersey tornado | IF3 | Researchers with the Tornado and Storm Research Organisation (TORRO), Met Office, and Jersey Met, published a case study on the storm which produced an intense tornado and a hailstorm on the island nation of Jersey. [25] |
| 2024 oThongathi tornado | EF3 | The South African Weather Service conducted a nine-day damage survey and case study on the rare tornado. [26] |
The Fujita scale, or Fujita–Pearson scale, is a scale for rating tornado intensity, based primarily on the damage tornadoes inflict on human-built structures and vegetation. The official Fujita scale category is determined by meteorologists and engineers after a ground or aerial damage survey, or both; and depending on the circumstances, ground-swirl patterns, weather radar data, witness testimonies, media reports and damage imagery, as well as photogrammetry or videogrammetry if motion picture recording is available. The Fujita scale was replaced with the Enhanced Fujita scale (EF-Scale) in the United States in February 2007. In April 2013, Canada adopted the EF-Scale over the Fujita scale along with 31 "Specific Damage Indicators" used by Environment Canada (EC) in their ratings.
This article lists various tornado records. The most "extreme" tornado in recorded history was the Tri-State tornado, which spread through parts of Missouri, Illinois, and Indiana on March 18, 1925. It is considered an F5 on the Fujita Scale, holds records for longest path length at 219 miles (352 km), longest duration at about 3+1⁄2 hours, and it held the fastest forward speed for a significant tornado at 73 mph (117 km/h) anywhere on Earth until 2021. In addition, it is the deadliest single tornado in United States history with 695 fatalities. It was also the third most costly tornado in history at the time, when costs are normalized for wealth and inflation, it still ranks third today.
During the afternoon of May 6, 1975, at least 12 tornadoes touched down in the Upper Midwest. The costliest of these tornadoes struck parts of western Omaha, Nebraska, causing at least $150 million in damage and killing three people. It was at the time the costliest tornado in U.S. history, damaging over a thousand homes across a nearly 2,000-block area on its roughly 15 mi (24 km) long path. The tornado's damage was later rated F4 on the Fujita scale. Another F4 tornado struck Magnet, Nebraska, destroying or damaging nearly every building in the town. The tornadoes were produced by thunderstorms moving across a narrow region of warm and moist air that had advanced northwards into the Upper Midwest as a result of a strong area of low pressure over South Dakota. Additional tornadoes on May 7 and May 8, including several in Louisiana, Texas, and Mississippi, were associated with the same storm system.
A tornado outbreak is the occurrence of multiple tornadoes spawned by the same synoptic scale weather system. The number of tornadoes required to qualify as an outbreak typically are at least six to ten, with at least two rotational locations or at least two supercells producing multiple tornadoes.
The Enhanced Fujita scale rates tornado intensity based on the severity of the damage they cause. It is used in some countries, including the United States and France The EF scale is also unofficially used in other countries including China.
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, and southern and southeastern Brazil, northern Mexico, eastern and western Australia, New Zealand, and far eastern Asia.
A satellite tornado is a tornado that revolves around a larger, primary tornado and interacts with the same mesocyclone. Satellite tornadoes occur apart from the primary tornado and are not considered subvortices; the primary tornado and satellite tornadoes are considered to be separate tornadoes. The cause of satellite tornadoes is not known. Such tornadoes are more often anticyclonic than are typical tornadoes and these pairs may be referred to as tornado couplets. Satellite tornadoes commonly occur in association with very powerful, large, and destructive tornadoes, indicative also of the strength and severity of the parent supercell thunderstorm.
On March 21–22, 1932, a deadly tornado outbreak struck the Midwestern and Southern United States. At least 38 tornadoes—including 27 deadly tornadoes and several long-lived tornado families—struck the Deep South, killing more than 330 people and injuring 2,141. Tornadoes affected areas from Mississippi north to Illinois and east to South Carolina, but Alabama was hardest hit, with 268 fatalities; the outbreak is considered to be the deadliest ever in Alabama, and among the worst ever in the United States, trailing only the Tri-State tornado outbreak in 1925, with 751 fatalities, and the Tupelo–Gainesville outbreak in 1936, with 454 fatalities. The 1932 outbreak is believed to have produced 10 violent tornadoes, eight of which occurred in Alabama alone.
On March 16–17, 1942, a deadly late-winter tornado outbreak struck a large area of the Central and Southern United States, killing 149 people and injuring at least 1,312. At least five states reported violent tornadoes, from Illinois and Indiana south to Mississippi, beginning with an F4 tornado in the morning in Illinois. Intense activity spread south to the Gulf Coast and north to the Michigan–Indiana border as the day went on. Seven violent tornadoes were reported, one of which was a powerful F5 in Illinois. A long-tracked F4 tornado family in Mississippi claimed 63 lives as well, becoming the deadliest event of the outbreak. Another long-lived F4 in Tennessee killed 15 more people, and a series of intense tornadoes caused 24 other deaths in Kentucky. The outbreak also produced 18 tornadoes that caused at least one death—ranking eighth on a list of similar events since 1880 by tornado researcher Thomas P. Grazulis.
The European Severe Storms Laboratory (ESSL) is a scientific organisation that conducts research on severe convective storms, tornadoes, intense precipitation events, and avalanches across Europe and the Mediterranean. It operates the widely consulted European Severe Weather Database (ESWD).
The 2013 El Reno tornado was an extremely large and powerful tornado that occurred over rural areas of Central Oklahoma during the early evening of Friday, May 31, 2013. This rain-wrapped, multiple-vortex tornado was the widest tornado ever recorded and was part of a larger weather system that produced dozens of tornadoes over the preceding days. The tornado initially touched down at 6:03 p.m. Central Daylight Time (2303 UTC) about 8.3 miles (13.4 km) west-southwest of El Reno, rapidly growing in size and becoming more violent as it tracked through central portions of Canadian County. Remaining over mostly open terrain, the tornado did not impact many structures; however, measurements from mobile weather radars revealed extreme winds in excess of 135 m/s within the vortex. These are among the highest observed wind speeds on Earth, just slightly lower than the wind speeds of the 1999 Bridge Creek–Moore tornado. As it crossed U.S. 81, it had grown to a record-breaking width of 2.6 miles (4.2 km), beating the previous width record set in 2004. Turning northeastward, the tornado soon weakened. Upon crossing Interstate 40, the tornado dissipated around 6:43 p.m. CDT (2343 UTC), after tracking for 16.2 miles (26.1 km), it avoided affecting the more densely populated areas near and within the Oklahoma City metropolitan area.
The International Fujita scale rates the intensity of tornadoes and other wind events based on the severity of the damage they cause. It is used by the European Severe Storms Laboratory (ESSL) and various other organizations including Deutscher Wetterdienst (DWD) and State Meteorological Agency (AEMET). The scale is intended to be analogous to the Fujita and Enhanced Fujita scales, while being more applicable internationally by accounting for factors such as differences in building codes.
This is a timeline of scientific and technological advancements as well as notable academic or government publications in the area of atmospheric sciences and meteorology during the 21st century. Some historical weather events are included that mark time periods where advancements were made, or even that sparked policy change.
The history of tornado research spans back centuries, with the earliest documented tornado occurring in 200 and academic studies on them starting in the 18th century. This is a timeline of government or academic research into tornadoes.