In meteorology, a cyclone is a large air mass that rotates around a strong center of low atmospheric pressure, counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere as viewed from above. Cyclones are characterized by inward-spiraling winds that rotate about a zone of low pressure. The largest low-pressure systems are polar vortices and extratropical cyclones of the largest scale. Warm-core cyclones such as tropical cyclones and subtropical cyclones also lie within the synoptic scale. Mesocyclones, tornadoes, and dust devils lie within the smaller mesoscale.
In meteorology, a low-pressure area, low area or low is a region where the atmospheric pressure is lower than that of surrounding locations. Low-pressure areas are commonly associated with inclement weather, while high-pressure areas are associated with lighter winds and clear skies. Winds circle anti-clockwise around lows in the northern hemisphere, and clockwise in the southern hemisphere, due to opposing Coriolis forces. Low-pressure systems form under areas of wind divergence that occur in the upper levels of the atmosphere (aloft). The formation process of a low-pressure area is known as cyclogenesis. In meteorology, atmospheric divergence aloft occurs in two kinds of places:
William "Bill" Mason Gray was emeritus professor of atmospheric science at Colorado State University (CSU), and the head of the Tropical Meteorology Project at CSU's Department of Atmospheric Sciences. He is widely regarded as a pioneer in the science of tropical cyclone forecasting and one of the world's leading experts on tropical storms. After retiring as a faculty member at CSU in 2005, Gray remained actively involved in both climate change and tropical cyclone research until his death.
Cyclone mitigation encompasses the actions and planning taken before a tropical cyclone strikes to mitigate damage and injury from the storm. Knowledge of tropical cyclone impacts on an area help plan for future possibilities. Preparedness may involve preparations made by individuals as well as centralized efforts by governments or other organizations. Tracking storms during the tropical cyclone season helps individuals know current threats. Regional Specialized Meteorological Centers and Tropical Cyclone Warning Centers provide current information and forecasts to help individuals make the best decision possible.
An Atlantic hurricane is a type of tropical cyclone that forms in the Atlantic Ocean primarily between June and November. The terms "hurricane", "typhoon", and "cyclone" can be used interchangeably to describe this weather phenomenon. These storms are rotating, organized systems of clouds and thunderstorms that originate over tropical or subtropical waters and have closed low-level circulation, not to be confused with tornadoes. They form over low pressure systems. In the North Atlantic, central North Pacific, and eastern North Pacific, the term "hurricane" is mainly used, whereas "typhoon" is more commonly used for storms originating in the western North Pacific. The term "cyclone" is used in the South Pacific and Indian Ocean.
Timothy Patrick Marshall is an American structural and forensic engineer as well as meteorologist, concentrating on damage analysis, particularly that from wind and other weather phenomena. He is also a pioneering storm chaser and was editor of Storm Track magazine.
Thomas P. Grazulis is an American meteorologist who has written extensively about tornadoes and is head of The Tornado Project.
The effects of tropical cyclones include heavy rain, strong wind, large storm surges near landfall, and tornadoes. The destruction from a tropical cyclone, such as a hurricane or tropical storm, depends mainly on its intensity, its size, and its location. Tropical cyclones remove forest canopy as well as change the landscape near coastal areas, by moving and reshaping sand dunes and causing extensive erosion along the coast. Even well inland, heavy rainfall can lead to landslides in mountainous areas. Their effects can be sensed over time by studying the concentration of the Oxygen-18 isotope within caves.
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.
James Marshall Shepherd is an American meteorologist, professor at the University of Georgia's Department of Geography, director of the university's atmospheric sciences program, and 2013 president of the American Meteorological Society (AMS). In 2020 he was awarded the AAAS Award for Public Engagement with Science. In 2021, he was elected to the U. S. National Academy of Engineering.
David Owen Blanchard is an American meteorologist, photographer, and storm chaser. He was a significant collaborator in seminal research on tornadogenesis, specifically the importance of baroclinic boundaries, the rear-flank downdraft (RFD) and its thermodynamic characteristics.
John Terrence Allen is an Australian atmospheric scientist and leading contributor to research on severe thunderstorm and tornado environments, particularly in the context of climate change, including seasonal prediction of hail and tornadoes. He is currently an assistant professor of meteorology at Central Michigan University. He was formerly a researcher at the International Research Institute for Climate and Society (IRI) at The Earth Institute (EI) of Columbia University.
Hurricane Isbell spawned one of the most significant tornado outbreaks to strike the Miami metropolitan area on October 14, 1964. It produced at least nine confirmed, and possibly as many as 17, tornadoes, four of which were rated significant (F2) on the Fujita scale. Although there were no fatalities, 48 people were injured and losses totaled $560,250. The most damaging of the tornadoes was an estimated F2 that injured 22 people at a mobile home park in Briny Breezes, causing $250,000 in losses.
On October 3–4, 1964, Hurricane Hilda and its remnants generated a tornado outbreak over portions of the Southeastern United States. The outbreak, which yielded at least 12 confirmed tornadoes, killed 22 people and injured 175 others. Most of the casualties occurred as a result of a violent tornado that devastated the northern outskirts of Larose, Louisiana, becoming the deadliest hurricane-generated tornado on record since 1900 and one of only two violent tornadoes (F4+) recorded in the southern Gulf Coast region of Louisiana. The tornado was also one of only two F4s known to have been produced by a tropical cyclone, the other having occurred during Hurricane Carla on September 12, 1961.
Sharon E. Nicholson is a meteorology professor at Florida State University (FSU) in the Department of Earth, Ocean and Atmospheric Science. Nicholson has been teaching about and researching climates of Africa. Nicholson has earned the Humboldt Award, the Fulbright Global Scholar award, a National Science Foundation Award.
Temi E. Ologunorisa is a Nigerian climate scientist. He served as Professor of Meteorology and Climate Science at the Federal University of Technology in Akure, Ondo State, Niger since 2016. He also teaches geography as an adjunct professor at Liberty University in Lynchburg, Virginia, and Kansas City Kansas Community College in Kansas, both in the United States. He formerly served as the executive director of the Center for Black Culture and International Understanding, an organization connected with UNESCO, in Osogbo, Nigeria (2015–2016), where concerns of black empowerment and diaspora studies take center stage. He is also serving has the Current Vice Chancellor at Olusegun Agagu University of Science and Technology, Okitipupa, Nigeria.
