History of tornado research

The history of tornado research goes back many years, with the earliest known tornado happening in 200 CE. People have been studying tornadoes for a long time, and real scientific work on them began in the 1700s. Many smart people have looked into these powerful storms to learn more about them. This article talks about the important studies and discoveries made by governments and scientists over the years to understand tornadoes better.

You can help improve this page by editing the page and adding missing information with references to reliable sources. This list keeps growing as we learn more about tornadoes.

Early studies

The earliest-known tornado happened in Sardinia and Corsica, which were part of the Roman Empire, in the year 200. Later, in 788, a tornado struck Freising in what is now Germany, and in 1054, one appeared in Ireland. In 1091, a powerful tornado hit London, England.

Scientists began studying tornadoes in the 1700s. In 1764, a very strong tornado hit Woldegk in Germany. A scientist named Gottlob Burchard Genzmer studied this tornado carefully. He looked at the damage path, talked to people who saw it, and examined where debris and hail landed. Modern scientists later determined this was one of the most intense tornadoes ever recorded.

Other early studies happened in many places. In 1819, a scientist in Poland described a tornado that damaged buildings and lifted a wagon into the air. In 1838, a slow-moving tornado caused damage near Calcutta, now called Kolkata, in India. In 1835, a deadly tornado struck New Jersey, and scientists examined the damage to better understand how tornadoes move and cause destruction.

Research by topic

Tornadogenesis

Main article: Tornadogenesis

In December 1898, Dr. B. F. Duke, along with Dr. Cleveland Abbe, published a paper about the United States's Weather Bureau's first official theory on how tornadoes form. This theory explained that winds moving in different directions meet to form a rapid updraft, creating a buoyant cloud that can form a tornado. Dr. Abbe also suggested the idea of horizontal vortices within tornadoes.

In 1960, Bernard Vonnegut proposed that electricity in thunderstorms might play a role in powering tornadoes.

Characteristics of tornadoes

Main article: Tornado § Characteristics

In April 1899, Dr. Cleveland Abbe and others studied tornado characteristics and found that tornadoes in the United States rotate counterclockwise, similar to large low-pressure systems.

In November 1900, a detailed study of a tornado outbreak in Tennessee, Mississippi, and Arkansas showed that one tornado split into two parts and had a zigzag motion. Another tornado in the outbreak traveled 215 miles at an average speed of 60 mph.

In 1901 and 1906, Frank H. Bigelow developed formulas to calculate the rotational speed of tornadoes based on height above sea level. His work helped develop the idea that tornadoes can form from gust fronts.

The 1957 Dallas tornado was studied extensively, proving some earlier theories about tornadoes were incorrect. Researchers used the first photogrammetric analysis of wind speeds in a tornado, and structural surveys contributed to the development of the Fujita scale.

During a violent tornado in Union City, Oklahoma in May 1973, the "Tornadic Vortex Signature" (TVS) was identified for the first time using experimental Doppler radar.

In 2018, researchers published a detailed analysis of the multiple-vortex nature of the 2013 El Reno, Oklahoma tornado.

Tornado watches and warnings

Main article: Tornado warning

In April 1899, a news article questioned why tornado warnings were not sent via telegraph or telephone. Cleveland Abbe responded that the destructive areas of tornadoes are so small that the chance of being injured is slight, and we do not attempt to prevent what is inevitable.

In June 1899, a U.S. Weather Bureau director mentioned that long-range forecasters in Oklahoma were causing unnecessary alarms and frightening people with predictions of tornadoes that did not occur.

In April 1908, the U.S. Weather Bureau published replies to questions on how to protect against tornadoes. Suggestions included watching distant tornadoes and moving away, establishing a warning system with wires and alarms around cities, and spending money on protection against other dangers like diseases and accidents instead of tornadoes.

On June 25, 1967, the Royal Netherlands Meteorological Institute issued the first-ever tornado forecast in Europe.

In May 2024, a new analysis of the 1985 United States–Canada tornado outbreak focused on Pennsylvania and Tornado Watch #211 issued by the National Weather Service.

Pressure

In 1896, a case study on the 1896 St. Louis–East St. Louis tornado included damage surveys and meteorological analysis. A special study by a civil engineer found that a barometer recorded a pressure of 671 millimetres of mercury directly under the tornado's center.

In August 2024, researchers published findings on pressure measurements and video observations inside three EF2 tornadoes using in-situ tornado probes. The probes recorded pressure drops and wind speeds inside the tornadoes.

Wind speeds

In January 1904, a case study on a tornado in Moundville, Alabama included wind speed measurements of up to 60 mph.

In March 1906, a case study on a tornado in Meridian, Mississippi included pressure, temperature, and wind speed measurements of up to 64 mph near the tornado.

In September 1958, a case study estimated that the 1957 Dallas tornado had winds of at least 302 mph.

The University of Oklahoma's RaXPol mobile Doppler weather radar measured winds preliminarily analyzed as in excess of 296 mph during the 1999 Bridge Creek–Moore tornado. The El Reno tornado also had a documented width of 2.6 miles, the widest tornado ever recorded.

Political

In April 2004, the Tornado Research Act of 2004 was introduced to create a new tornado research branch of the National Oceanic and Atmospheric Administration but failed and died in committee.

In April 2023, the TORNADO Act was introduced by U.S. Senator Roger Wicker and other senators.

In April 2023, the United States House of Representatives passed the Weather Research and Forecasting Innovation Reauthorization Act of 2023 to provide authority for the Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX-USA).

In July 2024, Senator Kyrsten Sinema and others introduced the Border Weather Resiliency Act, and Congressman Randy Feenstra introduced a bill to provide tax relief to people affected by severe storms, flooding, and tornadoes.

Frequency and locations

In June 1897, Cleveland Abbe published one of the first tornadic frequency tables for each state in the United States, noting that Kansas had the highest average number of tornadoes.

In April 1899, Abbe stated that the number of tornadoes in the United States was not truly increasing and that any increase was due to better newspaper and telegraph coverage.

In April 2024, researchers stated that the perceived shift in tornado activity from the traditional tornado alley in the Great Plains to the eastern U.S. is real.

In June 2024, researchers published a paper on regional and seasonal trends of tornadoes across the United States.

Sound

Main article: Tornadic infrasound

In February 1898, an observer for the United States Weather Bureau published a detailed study on the sounds of an approaching tornado: a gurgling noise, followed by rumbling, and finally a sound like a railroad train. This sequence is still described as the sound of a tornado today.

In May 2024, research determined that tornadoes emit dominant low-frequency infrasound between 0.5−1.2 Hertz.

Psychological

In April 2007, a case study involved first-hand accounts from survivors of a tornado in Escambia County, Florida on April 5, 1907, including some who were thrown by the tornado.

In February 2024, researchers published a study about how survivors of the 2011 Joplin tornado recover from "Tornado Brain," a new term for the PTSD of tornado survivors.

In July 2024, a paper examined the aftermath of the 2020 Nashville tornado, focusing on mental health issues of survivors and differences in recovery based on gender.

Media

See also: List of meteorological photos and videos

Photographs

In June 1907, the U.S. Weather Bureau published a damage survey and analysis on a tornado in Wills Point, Texas on May 25, 1907. The analysis included some of the first-ever photographs of a tornado.

Films

On July 19, 2024, the disaster film Twisters was released, which included accurate scientific theories on ways to potentially disrupt tornadoes.

Tornado outbreak and tornado family studies

In 1886, a case study was written on a tornado outbreak between September 12–18, 1886, studying 26 tornadoes that occurred during the outbreak.

In 1895, a case study was published on a tornado in Augusta, Georgia on March 20, 1895, along with a twin tornado and a satellite tornado.

In May 1898, a map was created of meteorological observations and tornado tracks that occurred on May 17, 1898.

Between April 3–4, 1974, a catastrophic Super Outbreak occurred across the United States, producing 148 tornadoes in a 24-hour period and leading to the deaths of 335 people. The outbreak was extensively studied, and new knowledge about tornadoes, such as downbursts and microbursts, was discovered.

In 1993, a book documented all known significant tornadoes in the United States going back to 1680.

In April 2011, the Super Outbreak, the largest and costliest tornado outbreak ever to occur, produced 360 tornadoes across the United States, leading to dozens of academic studies.

In November 2023, a new book included the outbreak intensity score (OIS), a new way to classify and rank tornado outbreaks.

In January 2024, an analysis and database of 74 tornadoes which occurred in South America was published.

In June 2024, a paper regarding how a prolonged and unusual pattern contributed to the formation of the tornado outbreak of December 10–11, 2021 was published.

In July 2024, information on a new database, called Tornado Archive, which contains information on more than 100,000 tornadoes was published. Also in July 2024, a quantitative definition for how to define a tornado outbreak was published. The analysis determined that between 1960 and 2021, the United States experienced 6,723 individual tornado outbreaks and that there is also a downward trend of 0.25 tornado outbreaks per year.

In September 2024, a study regarding the various environmental conditions associated with long-track tornadoes was published.

Intensity and rating of tornadoes

Main articles: Fujita scale, Enhanced Fujita scale, TORRO scale, International Fujita scale, and Disagreements on the intensity of tornadoes

In 1971, Ted Fujita introduced the Fujita scale to estimate a tornado's intensity. The scale was updated in 1973, and tornadoes across the United States were retroactively rated on the scale going back to 1950.

In 2002, a Service Assessment Team found that the local National Weather Service office failed to indicate the initial findings of F5 damage on the Fujita scale was "preliminary" to the media and public. The National Weather Service created a national Quick Response Team (QRT) to assess and analyze locations believed to have sustained F4 or F5 damage on the Fujita scale.

In February 2007, the Enhanced Fujita scale was formally released and put into use across the United States, replacing the Fujita scale. The 2007 Greensburg tornado family included the first tornado to receive the rating of EF5 on the Enhanced Fujita scale.

In April 2013, Environment Canada adopted a variation of the Enhanced Fujita scale, replacing the Fujita scale across Canada.

In May 2019, a large EF4 tornado affected the western Kansas City metropolitan area. A research team launched a custom-built meteorological rocket probe from a specialized interceptor vehicle into the inflow region of the tornado. The probe recorded instantaneous winds of 85.1 m/s (190 mph; 306 km/h), suggesting higher intensity than rated.

In March 2022, the National Weather Service published a new damage survey and analysis for the 2012 Henryville tornado, where a "possible EF5 damage" location is identified and discussed.

In July 2022, a research team was funded by the National Oceanic and Atmospheric Administration to investigate a stretch of the 2019 Greenwood Springs, Mississippi EF2 tornado where the National Weather Service was unable to survey. In their survey, the team noted that the tornado "produced forest devastation and electrical infrastructure damage up to at least EF4 intensity".

In 2022, a detailed damage survey and analysis of the 2021 Western Kentucky EF4 tornado was published. The researchers stated that "the tornado damage rating might have been higher had more wind resistant structures been encountered."

In July 2023, the International Fujita scale (IF-scale) was officially published. In April 2024, the first-ever detailed damage survey and analysis on the 2021 South Moravia tornado using the International Fujita scale was published.

In March 2024, researchers stated that ">20% of supercell tornadoes may be capable of producing EF4–EF5 damage" and questioned if a 0–5 ranking scale makes sense given current understanding.

In May 2024, researchers assessed extreme damage caused by tornadoes which is ineligible for ratings on the Canadian Enhanced Fujita scale or the American Enhanced Fujita scale (EF-scale). It was determined all three tornadoes caused damage well-beyond their assigned EF-scale ratings, with all three tornadoes having EF5-intensity winds.

On May 21, 2024, a violent EF4 tornado struck the town of Greenfield, Iowa. As the tornado moved through the town, a Doppler on Wheels measured winds of at least >250 mph (400 km/h), "possibly as high as 290 mph (470 km/h)" at 48 yards (44 m) above the surface. The peak wind speed estimate was revised to between 309 mph (497 km/h) and 318 mph (512 km/h) on June 22, 2024.

Forecast models

A few weeks after the 2024 Greenfield tornado, the National Oceanic and Atmospheric Administration released details about an experimental warning system which was tested before and during the tornado. This new warning system, named Warn-on-Forecast (WoFS) System, was created by the Hazardous Weather Testbed housed in the National Weather Center in Norman, Oklahoma. During the experiment and test, the WoFS gave a high indication of “near-ground rotation” in and around the area of Greenfield, Iowa between 2-4 p.m. According to the press release, 75-minutes later, the violent EF4 tornado touched down. Scientists with the National Severe Storms Laboratory were able to give local National Weather Service forecasters a 75-minute lead time for the tornado.

Field research projects

See also: List of United States government meteorology research projects

Between 2019 and 2023, the Targeted Observation by Radars and UAS of Supercells (TORUS) project occurred, led by the University of Nebraska–Lincoln, along with the NOAA NSSL, NOAA Office of Marine and Aviation Operations, CIWRO, and Texas Tech University, and the University of Colorado Boulder.

Between March 2022 and April 2023, the Propagation, Evolution, and Rotation in Linear Storms (PERiLS) Project occurred. The project involved over a hundred people from sixteen organizations and was described as "the largest and most ambitious study focused on improving the understanding of tornadoes associated with linear storms." The PERiLS Project was funded by two grants from the National Science Foundation, three grants from the NOAA's VORTEX-USA program, and a grant from the United States Department of Commerce.

Between December 2023 – April 2024, the Detecting and Evaluating Low-level Tornado Attributes (DELTA) project occurred, led by NOAA, along with the National Severe Storms Laboratory and several research universities.

On February 8, 2024, meteorologist and storm chaser Reed Timmer, along with Mark Simpson, Sean Schofer, Curtis Brooks, published a paper about the design of and information about a new meteorological rocket probe which can be launched into tornadoes. The researchers launched one of these rocket probes into the 2019 Lawrence–Linwood EF4 tornado. The probe recorded winds of 85.1 m/s (190 mph; 306 km/h) during its first rotation around the tornado and also recorded a pressure drop of 113.5 hPa (113.5 mb) inside the tornado. The probe also recorded that the tornado's updraft was 65.0 m/s (145 mph; 234 km/h). The tornado threw the probe 32 mi (51 km), where the researchers were able to recover it.

In mid-April 2024, the National Severe Storms Laboratory along with Texas Tech University began the Low-Level Internal Flows in Tornadoes (LIFT) Project, with the goal to collect data from the "damage layer" of tornadoes; from ground level to 20 m (22 yd) above the surface. The LIFT project deployed 11 times between April–June, gathering data from "numerous successful intercepts".

Engineering

In February 2024, researchers published an academic case study on how hurricane-resistant houses performed during the 2022 Arabi–New Orleans EF3 tornado.

Other events or research

In July 1899, a case study was conducted on a violent tornado which struck New Richmond, Wisconsin on June 12, 1899.

In May 1902, a case study and damage survey for a tornado which struck northeastern Mississippi and northwestern Alabama on March 28, 1902 was published.

In June 1903, a case study on a tornado which struck Gainesville, Georgia on June 1, 1903 was published.

In August 1905, a detailed case study for a damage survey of the violent and deadly 1905 Snyder, Oklahoma tornado was published.

In June 1908, a detailed case study, specifically on the complete description and timeline of a tornado near Fort Worth, Texas on May 29, 1908 was published.

On March 18, 1925, the violent Tri-State tornado occurred, killing 695 people and injuring 2,027 people, while traveling 219 miles (352 km) over a period of 3 hours and 45 minutes. At one point, the tornado was moving with a forward speed of 73 miles per hour (117 km/h), setting the record as the fastest forward moving violent tornado in history. The tornado also became the deadliest tornado in United States history as well as the longest traveled tornado in history.

Between 1945 and 1946, an extensive survey and assessment of the tornado outbreak of February 12, 1945, and the 1945 Montgomery–Chisholm tornado was undertaken.

In August 2008, a detailed damage survey and analysis for the 2008 Parkersburg–New Hartford tornado was published.

In October 2006, a case study on a tornadic storm in southern England on December 30, 2006 was published.

In April 2014, a detailed damage survey and analysis of the 2014 Mayflower–Vilonia, Arkansas EF4 tornado was published. In October, a detailed damage survey and analysis on the 2013 Moore, Oklahoma EF5 tornado was published.

In May 2020, a detailed damage survey and analysis on the 2011 Tuscaloosa–Birmingham EF4 tornado was published.

In January 2023, the 2023 Pasadena–Deer Park tornado prompted the National Weather Service forecasting office in Houston to issue a rare tornado emergency, the first ever issued by the office.

In September 2023, a joint damage survey and analysis on the 2023 Rolling Fork–Silver City EF4 tornado, the 2023 Black Hawk–Winona EF3 tornado, and the 2023 New Wren–Amory EF3 tornado was published.

In February 2024, a case study on the storm which produced an intense tornado and a hailstorm on the island nation of Jersey in November 2023 was published.

In August 2024, an investigation into "230 significant tornadoes, 246 significant hail events, and 191 null cases across the United States" and how cell mergers, boundaries, other supercells, along with other meteorological phenomenon interact and what impacts do they have on tornadoes and significant hail was published. During August 2024, a paper on how tornadoes devastated the tsuga canadensis, commonly known as eastern hemlock, in part of Alabama was published.