Greensburg, Kansas is almost completely destroyed by a 1.7 mi wide EF5 tornado. It was the first-ever tornado to be rated as such with the new Enhanced Fujita scale.
The Enhanced Fujita scale (abbreviated as EF-Scale) rates the intensity of tornadoes based on the severity of the damage they cause. It is used in some countries, including the United States and Canada.
The Enhanced Fujita scale replaced the decommissioned Fujita scale that was introduced in 1971 by Ted Fujita. Operational use began in the United States on February 1, 2007, followed by Canada on April 1, 2013. It has also been proposed for use in France. The scale has the same basic design as the original Fujita scalesix intensity categories from zero to five, representing increasing degrees of damage. It was revised to reflect better examinations of tornado damage surveys, in order to align wind speeds more closely with associated storm damage. Better standardizing and elucidating what was previously subjective and ambiguous, it also adds more types of structures and vegetation, expands degrees of damage, and better accounts for variables such as differences in construction quality. An "EF-Unknown" (EFU) category was later added for tornadoes that cannot be rated due to a lack of damage evidence.The newer scale was publicly unveiled by the National Weather Service at a conference of the American Meteorological Society in Atlanta on February 2, 2006. It was developed from 2000 to 2004 by the Fujita Scale Enhancement Project of the Wind Science and Engineering Research Center at Texas Tech University, which brought together dozens of expert meteorologists and civil engineers in addition to its own resources.As with the Fujita scale, the Enhanced Fujita scale remains a damage scale and only a proxy for actual wind speeds. While the wind speeds associated with the damage listed have not undergone empirical analysis (such as detailed physical or any numerical modeling) owing to excessive cost, the wind speeds were obtained through a process of expert elicitation based on various engineering studies since the 1970s as well as from field experience of meteorologists and engineers. In addition to damage to structures and vegetation, radar data, photogrammetry, and cycloidal marks (ground swirl patterns) may be utilized when available.
The scale was used for the first time in the United States a year after its public announcement when parts of central Florida were struck by multiple tornadoes, the strongest of which were rated at EF3 on the new scale. It was used for the first time in Canada shortly after its implementation there when a tornado developed near the town of Shelburne, Ontario, on April 18, 2013, causing up to EF1 damage.
Greensburg is a city in, and the county seat of, Kiowa County, Kansas, United States. As of the 2020 census, the population of the city was 740. It is home to the world's largest hand-dug well. On the evening of May 4, 2007, Greensburg was devastated by an EF5 tornado that leveled at least 95 percent of the city and killing eleven people between the ages of 46 and 84. Today, Greensburg stands as a model "green town", often described as the greenest in America. The hospital, city hall, and school have all been built to the highest certification level issued by Leadership in Energy and Environmental Design (LEED).