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.
Tetsuya Theodore Fujita was a Japanese and American meteorologist whose research primarily focused on severe weather. His research at the University of Chicago on severe thunderstorms, tornadoes, hurricanes, and typhoons revolutionized the knowledge of each. Although he is best known for creating the Fujita scale of tornado intensity and damage, he also discovered downbursts and microbursts and was an instrumental figure in advancing modern understanding of many severe weather phenomena and how they affect people and communities, especially through his work exploring the relationship between wind speed and damage.
Storm Track was the first magazine for and about storm chasing. The magazine was in circulation between 1977 and 2002.
The TORRO tornado intensity scale is a scale measuring tornado intensity between T0 and T11. It was proposed by Terence Meaden of the Tornado and Storm Research Organisation (TORRO), a meteorological organisation in the United Kingdom, as an extension of the Beaufort scale.
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.
This page documents notable tornadoes and tornado outbreaks worldwide in 2004. Strong and destructive tornadoes form most frequently in the United States, Bangladesh, and Eastern India, but they can occur almost anywhere under the right conditions. Tornadoes also develop occasionally in southern Canada during the Northern Hemisphere's summer and somewhat regularly at other times of the year across Europe, Asia, and Australia. Tornadic events are often accompanied with other forms of severe weather, including strong thunderstorms, strong winds, and hail.
Joshua Michael Aaron Ryder Wurman is an American atmospheric scientist and inventor noted for tornado, tropical cyclone, and weather radar research, the invention of DOW and bistatic radar multiple-Doppler networks.
On May 24–25, 1957, a tornado outbreak primarily affected the Western High Plains, Central Great Plains, and Central Oklahoma/Texas Plains of the United States. 45 tornadoes touched down over the area, most of which took place across northern and western Texas, in addition to southern Oklahoma. Overall activity initiated over eastern New Mexico and spread northeastward as far as southwestern Wisconsin. The strongest tornado, which occurred in southern Oklahoma on May 24, was assigned a rating of F4 near Lawton. Anomalously, some tornadoes touched down during the early morning hours, rather than late afternoon or early evening, when daytime heating typically peaks.
On April 2–5, 1957, a deadly tornado outbreak sequence struck most of the Southern United States. The outbreak killed at least 21 people across three states and produced at least 73 tornadoes from Texas to Virginia. The outbreak was most notable due to a tornado that hit a densely populated area of the Dallas–Fort Worth metropolitan area, killing 10 people and injuring 200 or more. The tornado, highly visible for most of its path, was at the time the most observed and best-documented tornado in recorded history; hundreds of people photographed or filmed the F3 tornado as it moved just west of Downtown Dallas. The film of this tornado is still known for its unusually high quality and sharpness, considering the photography techniques and technology of the 1950s. Damage from the Dallas tornado reached as high as $4 million. Besides the famous Dallas tornado, other deadly tornadoes struck portions of Mississippi, Texas, and Oklahoma. Two F4 tornadoes struck southern Oklahoma on April 2, killing five people. Three other significant, F2-rated tornadoes that day killed two people in Texas and one more in Oklahoma. An F3 tornado struck rural Mississippi on April 4, killing one more person.
Tornadoes are more common in the United States than in any other country or state. The United States receives more than 1,200 tornadoes annually—four times the amount seen in Europe. Violent tornadoes—those rated EF4 or EF5 on the Enhanced Fujita Scale—occur more often in the United States than in any other country.
On June 18–19, 1972, Hurricane Agnes generated the third-deadliest tropical cyclone-related tornado outbreak in the United States since 1900, as well as the deadliest such tornado outbreak on record in Florida. The outbreak lasted about 38 hours and produced at least 19 confirmed tornadoes, though some studies suggested nearly a dozen more. Two of the tornadoes killed a total of seven people and were not classified as tornadoes by the National Weather Service until 2018. In Florida alone, the outbreak inflicted at least 135 injuries and destroyed 15 homes, while 119 homes received damage. Statewide, 217 trailers were destroyed and 196 trailers incurred damage. Additionally, six businesses were destroyed, while six others were damaged.
The 2013 El Reno tornado was an extremely large, powerful, and erratic 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 313 mph (504 km/h) 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 following is a glossary of tornado terms. It includes scientific as well as selected informal terminology.
James M. Leonard, also known as "Cyclone Jim", was an American professional storm chaser, photographer, and videographer. Intercepting severe weather including thunderstorms, tornadoes, hurricanes and typhoons, he was among the earliest storm chasers. He was the first to photograph an anticyclonic tornado.
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.
