A thunderstorm, also known as an electrical storm or a lightning storm, is a storm characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere, known as thunder. Relatively weak thunderstorms are sometimes called thundershowers. Thunderstorms occur in a type of cloud known as a cumulonimbus. They are usually accompanied by strong winds and often produce heavy rain and sometimes snow, sleet, or hail, but some thunderstorms produce little precipitation or no precipitation at all. Thunderstorms may line up in a series or become a rainband, known as a squall line. Strong or severe thunderstorms include some of the most dangerous weather phenomena, including large hail, strong winds, and tornadoes. Some of the most persistent severe thunderstorms, known as supercells, rotate as do cyclones. While most thunderstorms move with the mean wind flow through the layer of the troposphere that they occupy, vertical wind shear sometimes causes a deviation in their course at a right angle to the wind shear direction.
A weather station is a facility, either on land or sea, with instruments and equipment for measuring atmospheric conditions to provide information for weather forecasts and to study the weather and climate. The measurements taken include temperature, atmospheric pressure, humidity, wind speed, wind direction, and precipitation amounts. Wind measurements are taken with as few other obstructions as possible, while temperature and humidity measurements are kept free from direct solar radiation, or insolation. Manual observations are taken at least once daily, while automated measurements are taken at least once an hour. Weather conditions out at sea are taken by ships and buoys, which measure slightly different meteorological quantities such as sea surface temperature (SST), wave height, and wave period. Drifting weather buoys outnumber their moored versions by a significant amount.
The Meteorological Office, abbreviated as the Met Office, is the United Kingdom's national weather service. It is an executive agency and trading fund of the Department for Science, Innovation and Technology and is led by CEO Penelope Endersby, who took on the role as Chief Executive in December 2018 and is the first woman to do so. The Met Office makes meteorological predictions across all timescales from weather forecasts to climate change.
The National Severe Storms Laboratory (NSSL) is a National Oceanic and Atmospheric Administration (NOAA) weather research laboratory under the Office of Oceanic and Atmospheric Research. It is one of seven NOAA Research Laboratories (RLs).
In meteorology, a heat burst is a rare atmospheric phenomenon characterized by a sudden, localized increase in air temperature near the Earth's surface. Heat bursts typically occur during night-time and are associated with decaying thunderstorms. They are also characterized by extremely dry air and are sometimes associated with very strong, even damaging, winds.
In meteorology and climatology, a mesonet, portmanteau of mesoscale network, is a network of automated weather and, often also including environmental monitoring stations, designed to observe mesoscale meteorological phenomena and/or microclimates.
A flood warning is closely linked to the task of flood forecasting. The distinction between the two is that the outcome of flood forecasting is a set of forecast time-profiles of channel flows or river levels at various locations, while "flood warning" is the task of making use of these forecasts to make decisions about whether warnings of floods should be issued to the general public or whether previous warnings should be rescinded or retracted.
A satellite tornado is a tornado that revolves around a larger, primary tornado and interacts with the same mesocyclone. Satellite tornadoes occur apart from the primary tornado and are not considered subvortices; the primary tornado and satellite tornadoes are considered to be separate tornadoes. The cause of satellite tornadoes is not known. Such tornadoes are more often anticyclonic than are typical tornadoes and these pairs may be referred to as tornado couplets. Satellite tornadoes commonly occur in association with very powerful, large, and destructive tornadoes, indicative also of the strength and severity of the parent supercell thunderstorm.
The Verification of the Origins of Rotation in Tornadoes Experiment are field experiments that study tornadoes. VORTEX1 was the first time scientists completely researched the entire evolution of a tornado with an array of instrumentation, enabling a greater understanding of the processes involved with tornadogenesis. A violent tornado near Union City, Oklahoma was documented in its entirety by chasers of the Tornado Intercept Project (TIP) in 1973. Their visual observations led to advancement in understanding of tornado structure and life cycles.
A wake low, or wake depression, is a mesoscale low-pressure area which trails the mesoscale high following a squall line. Due to the subsiding warm air associated with the system's formation, clearing skies are associated with the wake low. Once difficult to detect in surface weather observations due to their broad spacing, the formation of mesoscale weather station networks, or mesonets, has increased their detection. Severe weather, in the form of high winds, can be generated by the wake low when the pressure difference between the mesohigh preceding it and the wake low is intense enough. When the squall line is in the process of decay, heat bursts can be generated near the wake low. Once new thunderstorm activity along the squall line concludes, the wake low associated with it weakens in tandem.
MesoWest is a cooperative project to observe and archive mesoscale weather observations across the United States. Their observations include but are not limited to temperature, humidity, wind speed, wind direction, and precipitation. Their data is also known to be central for climate records, such as for monitoring microclimates.
From May 3 to May 11, 2003, a prolonged and destructive series of tornado outbreaks affected much of the Great Plains and Eastern United States. Most of the severe activity was concentrated between May 4 and May 10, which saw more tornadoes than any other week-long span in recorded history; 335 tornadoes occurred during this period, concentrated in the Ozarks and central Mississippi River Valley. Additional tornadoes were produced by the same storm systems from May 3 to May 11, producing 363 tornadoes overall, of which 62 were significant. Six of the tornadoes were rated F4, and of these four occurred on May 4, the most prolific day of the tornado outbreak sequence; these were the outbreak's strongest tornadoes. Damage caused by the severe weather and associated flooding amounted to US$4.1 billion, making it the costliest U.S. tornado outbreak of the 2000s. A total of 50 deaths and 713 injuries were caused by the severe weather, with a majority caused by tornadoes; the deadliest tornado was an F4 that struck Madison and Henderson counties in Tennessee, killing 11.
Yvette Richardson is an American meteorologist with substantial contributions on tornado dynamics, tornadogenesis, the environments of tornadoes, supercells, and severe convection, and radar observations of these. She was a principal investigator (PI) of VORTEX2.
The combination of topographic and climatic factors in the Tulsa, Oklahoma area have frequently caused major flash flooding, especially near streams that normally drain the area. The city was founded atop a bluff on the Arkansas River. Thus, elevation protected most of the inhabitants and their possessions from damage when the river flooded. However, by the turn of the 20th century the population growth had moved closer to the river, and the flatlands west of the Arkansas had begun to develop as well. The floods typically caused widespread property damage and sometimes death. By the 1920s, seasonal floods of the Arkansas began to cause serious damage and loss of life. Since its founding, city leaders had responded to such events by simply rebuilding and replacing the property that had been destroyed in situ. Not until 1970 did the city government begin developing strategies to mitigate floods or at least minimize property damage and prevent loss of life. This article describes some of the more notable floods in Tulsa, then the mitigation and control strategies that evolved from them.
Preceded by more than a week of heavy rain, a slow-moving storm system dropped tremendous precipitation across much of Texas and Oklahoma during the nights of May 24–26, 2015, triggering record-breaking floods. Additionally, many areas reported tornado activity and lightning. Particularly hard hit were areas along the Blanco River in Hays County, Texas, where entire blocks of homes were leveled. On the morning of May 26, the National Weather Service issued a flash flood emergency for southwest Harris County and northeast Fort Bend County. The system also produced deadly tornadoes in parts of Mexico, Texas, and Oklahoma. This flood significantly contributed to the wettest month ever for Texas and Oklahoma.
The tornado outbreak sequence of May 2019 was a prolonged series of destructive tornadoes and tornado outbreaks affecting the United States over the course of nearly two weeks, producing a total of 402 tornadoes, including 53 significant events (EF2+). Eighteen of these were EF3 tornadoes, spanning over multiple states, including Nebraska, Kansas, Texas, Missouri, Oklahoma, Indiana, Iowa, and Ohio, with additional tornadoes confirmed across a region extending from California to New Jersey. Two EF4 tornadoes occurred, one in Dayton, Ohio, and the other in Linwood, Kansas. Four tornadoes during this outbreak were fatal, causing a total of eight fatalities. The deadliest of these occurred on May 22 near Golden City, Missouri, where an EF3 tornado took three lives, including an elderly couple in their eighties. The damaging series of tornadoes that occurred in Indiana and Ohio on the evening of May 27 during this event is sometimes locally referred to as the Memorial Day tornado outbreak of 2019, which became the 4th costliest weather event in Ohio history.
A significant late-season tornado outbreak took place on November 4, 2022, across Northeast Texas, southwestern Arkansas, southeastern Oklahoma, and northwestern Louisiana with multiple large, destructive tornadoes occurring over a span of several hours. Major damage was reported in Sulphur Springs, Powderly, Caviness, Paris, Cason, Daingerfield, Athens, New Boston, Texas, and Idabel, Oklahoma, with the latter two communities being placed under tornado emergencies. Two fatalities occurred in Cason, Texas, and Pickens, Oklahoma respectively. Numerous PDS tornado warnings were issued as well. An additional tornado embedded within a narrow, but intense line of showers with damaging winds was also confirmed in Illinois the following morning as the system progressed eastward. Strong winds affected most of the western Great Lakes throughout the day before moving into Canada that evening. Two fatalities and at least 34 injuries were confirmed from tornadoes, and an additional fatality occurred near Stilwell, Oklahoma from drowning.
A weather drone, or weather-sensing uncrewed aerial vehicle (UAV), – is a remotely piloted aircraft weighing less than 25 kg and carrying sensors that collect thermodynamic and kinematic data from the mid and lower atmosphere.
A multi-day period of significant tornado and severe weather activity occurred across the Southern United States, Ohio Valley, and southern High Plains in mid-June 2023. Starting on June 14, tornadoes occurred in Texas, Alabama, and Georgia, where they caused large-scale damage to trees and structures. The tornado outbreak continued on June 15, where tornadoes occurred in five states, including one EF3 tornado which touched down in Perryton, Texas, causing three fatalities. More tornadoes touched down on June 16 in the southern and northeastern United States, including an unusual anticyclone tornado in Mobile and Baldwin counties in Alabama, where the tornado itself was associated with the anticyclonic bookend vortex of a powerful mesoscale convective system. More tornadoes occurred on June 17 and 18, including another EF3 tornado that struck Louin, Mississippi, inflicting widespread major damage, killing one person, and injuring twenty-five others. Multiple tornadoes affected Smith County, Mississippi as well.
