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Glossary Of Tornado Terms
The following is a glossary of tornado terms. It includes scientific as well as selected informal terminology. A * ''Advanced Radar Research Center'' (ARRC) * ''Advection'' * ''Air parcel'' * ''American Geophysical Union'' (AGU) * ''American Meteorological Society'' (AMS) * ''Anticipated convection'' (AC) – A convective outlook. * ''Angular momentum'' * ''Anticyclone'' * ''Anticyclonic rotation'' * ''Anticyclonic tornado'' * ''Anticyclogenesis'' * ''Arcus cloud'' * ''Atmosphere'' * ''Atmospheric pressure'' B * ''Baroclinity'' or ''baroclinicity'' – baroclinic * '' Barotropity or ''barotropicity'' – barotropic * Bear's cage – (tornado chaser slang) The precipitation that wraps around a mesocyclone, possibly hiding a tornado on the ground. * ''Beaufort scale'' * ''Bernoulli's principle'' * Blob – Informal term coined by Erik N. Rasmussen for a descending reflectivity core (DRC). * Boundary * ''Bounded weak echo region'' (BWER) * ''Bow echo'' * BRN shear * '' Bulk ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tornado
A tornado is a violently rotating column of air that is in contact with the surface of Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. It is often referred to as a twister, whirlwind or cyclone, although the word cyclone is used in meteorology to name a weather system with a low-pressure area in the center around which, from an observer looking down toward the surface of the Earth, winds blow counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. Tornadoes come in many shapes and sizes, and they are often (but not always) visible in the form of a funnel cloud, condensation funnel originating from the base of a cumulonimbus cloud, with a cloud of rotating debris and dust beneath it. Most tornadoes have wind speeds less than , are about across, and travel several kilometers (a few miles) before dissipating. The Tornado records#Highest winds observed in a tornado, most extreme tornadoes can attain wind speeds of mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beaufort Scale
The Beaufort scale ( ) is an empirical measure that relates wind speed to observed conditions at sea or on land. Its full name is the Beaufort wind force scale. It was devised in 1805 by Francis Beaufort a hydrographer in the Royal Navy. It was officially adopted by the Royal Navy and later spread internationally. History The scale that carries Beaufort's name had a long and complex evolution from the previous work of others (including Daniel Defoe the century before). In the 18th century, naval officers made regular weather observations, but there was no standard scale and so they could be very subjective — one man's "stiff breeze" might be another's "soft breeze"—: Beaufort succeeded in standardising a scale.reprinted in 2003 by Dover Publications./ref> The scale was devised in 1805 by Francis Beaufort (later Rear Admiral), a hydrographer and a Royal Navy officer, while serving on , and refined until he was Hydrographer of the Navy in the 1830s, when it was ado ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cooperative Institute For Mesoscale Meteorological Studies
The Cooperative Institute for Severe and High-Impact Weather Research and Operations (CIWRO) is one of 16 NOAA Cooperative Institutes (CIs), hosted at the University of Oklahoma. Before Oct. 1, 2021, it was known as the Cooperative Institute for Mesoscale Meteorological Studies (CIMMS). The CIMMS/CIWRO, a research organization created in 1978 by a cooperative agreement between the University of Oklahoma (OU) and the National Oceanic and Atmospheric Administration (NOAA), promotes collaborative research between NOAA and OU scientists on problems of mutual interest to improve basic understanding of mesoscale meteorological phenomena, weather radar, and regional climate to help produce better forecasts and warnings that save lives and property. CIMMS/CIWRO research contributes to the NOAA mission through improvement of the observation, analysis, understanding, and prediction of weather elements and systems and climate anomalies ranging in size from cloud nuclei to multi-state areas. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cloud
In meteorology, a cloud is an aerosol consisting of a visible mass of miniature liquid droplets, frozen crystals, or other particles, suspended in the atmosphere of a planetary body or similar space. Water or various other chemicals may compose the droplets and crystals. On Earth, clouds are formed as a result of saturation of the air when it is cooled to its dew point, or when it gains sufficient moisture (usually in the form of water vapor) from an adjacent source to raise the dew point to the ambient temperature. Clouds are seen in the Earth's homosphere, which includes the troposphere, stratosphere, and mesosphere. Nephology is the science of clouds, which is undertaken in the cloud physics branch of meteorology. The World Meteorological Organization uses two methods of naming clouds in their respective layers of the homosphere, Latin and common name. Genus types in the troposphere, the atmospheric layer closest to Earth's surface, have Latin names because of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colorado Low
A Colorado low is a low-pressure area that forms in southeastern Colorado or northeastern New Mexico, typically in the winter. After forming, the system moves across the Great Plains. Colorado lows can produce heavy wintry precipitation, and have a general east to northeast movement, impacting regions as far north as Winnipeg and as far east as the Atlantic coast. If upper-level conditions are right, the jet stream can push the low farther south, bringing wintry precipitation as far as Texas. When pushed this far south, the system is often referred to as a " blue norther". On the more typical track, a Colorado low can be similar to an Alberta clipper. In the winter Colorado lows are responsible for a majority of the snow that the Midwest receives; however, summer systems can trigger long-lasting convective systems, including severe weather. Spring and early summer Colorado low cyclogenesis can result in significant tornado outbreaks over the Great Plains and Midwest. See also * De ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cold Front
A cold front is the leading edge of a cooler mass of air at ground level that replaces a warmer mass of air and lies within a pronounced surface Trough (meteorology), trough of Low-pressure area, low pressure. It often forms behind an extratropical cyclone (to the west in the Northern Hemisphere, to the east in the Southern Hemisphere, Southern), at the leading edge of its cold air Advection#Meteorology, advection pattern—known as the cyclone's dry "conveyor belt" flow. Temperature differences across the boundary can exceed from one side to the other. When enough moisture is present, rain can occur along the boundary. If there is significant Convective instability, instability along the boundary, a Squall line, narrow line of thunderstorms can form along the frontal zone. If instability is weak, a broad shield of rain can move in behind the Weather front, front, and evaporative cooling of the rain can increase the temperature difference across the front. Cold fronts are stronger ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Center For Analysis And Prediction Of Storms
The Center for Analysis and Prediction of Storms (CAPS) was established at the University of Oklahoma in 1989 as one of the first eleven National Science Foundation Science and Technology Centers. Located at the National Weather Center in Norman, Oklahoma, its mission is the development of techniques for the computer-based prediction of high-impact local weather, such as individual spring and winter storms, with the NEXRAD (WSR-88D) Doppler weather radar serving as a key data source. Activities Since 1989, scientists in CAPS have developed and improved ARPS (The Advanced Regional Prediction System). ARPS is a comprehensive regional to storm-scale atmospheric modeling/prediction system. It is a complete system that includes a realtime data analysis and assimilation system, the forward prediction model and a post-analysis package. ARPS has been used successfully in many real thunderstorm cases in research. Development and project CAPS, along with several other University of Okl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capping Inversion
A capping inversion is an elevated inversion layer that caps a convective planetary boundary layer. The boundary layer is the part of the atmosphere which is closest to the ground. Normally, the sun heats the ground, which in turn heats the air just above it. Thermals form when this warm air rises into the cold air (warm air is less dense than cold air), a process called convection. A convective layer such as this has the potential for cloud formation, since condensation occurs as the warm air rises and cools. An inversion occurs when the normal temperature (warm air below, cold air above) profile is reversed, creating a stable configuration of dense, cold air sitting below lighter, warm air. An elevated inversion layer is thus a region of warm air above a region of cold air, but higher in the atmosphere (generally not touching the surface). A capping inversion occurs when there is a boundary layer with a normal temperature profile (warm air rising into cooler air) and th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buoyancy
Buoyancy (), or upthrust, is the force exerted by a fluid opposing the weight of a partially or fully immersed object (which may be also be a parcel of fluid). In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus, the pressure at the bottom of a column of fluid is greater than at the top of the column. Similarly, the pressure at the bottom of an object submerged in a fluid is greater than at the top of the object. The pressure difference results in a net upward force on the object. The magnitude of the force is proportional to the pressure difference, and (as explained by Archimedes' principle) is equivalent to the weight of the fluid that would otherwise occupy the submerged volume of the object, i.e. the Displacement (fluid), displaced fluid. For this reason, an object with average density greater than the surrounding fluid tends to sink because its weight is greater than the weight of the fluid it displaces. If the objec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bow Echo
A bow echo is the characteristic radar return from a mesoscale convective system that is shaped like an archer's bow. These systems can produce severe straight-line winds and occasionally tornadoes, causing major damage. They can also become derechos or form Line echo wave pattern (LEWP). Research The term "bow echo" was first used by Theodore Fujita in his May 1978 paper "Manual of Downburst Identification for Project NIMROD." In 2004, research was done to better anticipate the formation of bow echoes, specifically the formation of bow echoes from weakly organized squall lines and supercells. Researchers determined that bow echoes were most likely to occur in weakly organized cells. A Midwest Bow Echo Workshop was held in 2007, at which meteorologists gathered to share their research to better understand bow echoes. Formation A bow echo is associated with squall lines or lines of convective thunderstorms. These echoes can range in size from 20 to 200 km, and hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bounded Weak Echo Region
The bounded weak echo region, also known as a BWER or a vault, is a Weather radar, radar signature within a thunderstorm characterized by a local minimum in radar reflectivity at low levels which extends upward into, and is surrounded by higher reflectivities aloft, forming a kind of dome of weak echoes. This feature is associated with a strong updraft and is almost always found in the inflow region of a thunderstorm: it cannot be seen visually. The BWER has been noted on radar imagery of severe thunderstorms since 1973 and has a lightning detection system equivalent known as a ''lightning hole''.Martin J. Murphy and Nicholas W. S. DemetriadesAn Analysis of Lightning Holes in a DFW Supercell Storm Using Total Lightning and Radar Information.Retrieved on 2008-01-08. Description and attributes The BWER is a nearly vertical channel of weak radar echo, surrounded on the sides and top by significantly stronger echoes. The BWER, sometimes called a vault, is related to the strong updra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
