HOME
*



picture info

Thunderstorm
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 caus ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Supercell
A supercell is a thunderstorm characterized by the presence of a mesocyclone: a deep, persistently rotating updraft. Due to this, these storms are sometimes referred to as rotating thunderstorms. Of the four classifications of thunderstorms (supercell, squall line, multi-cell, and single-cell), supercells are the overall least common and have the potential to be the most severe. Supercells are often isolated from other thunderstorms, and can dominate the local weather up to away. They tend to last 2–4 hours. Supercells are often put into three classification types: classic (Normal precipitation level), low-precipitation (LP), and high-precipitation (HP). LP supercells are usually found in climates that are more arid, such as the high plains of the United States, and HP supercells are most often found in moist climates. Supercells can occur anywhere in the world under the right pre-existing weather conditions, but they are most common in the Great Plains of the United Stat ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Lightning
Lightning is a naturally occurring electrostatic discharge during which two electrically charged regions, both in the atmosphere or with one on the ground, temporarily neutralize themselves, causing the instantaneous release of an average of one gigajoule of energy. This discharge may produce a wide range of electromagnetic radiation, from heat created by the rapid movement of electrons, to brilliant flashes of visible light in the form of black-body radiation. Lightning causes thunder, a sound from the shock wave which develops as gases in the vicinity of the discharge experience a sudden increase in pressure. Lightning occurs commonly during thunderstorms as well as other types of energetic weather systems, but volcanic lightning can also occur during volcanic eruptions. The three main kinds of lightning are distinguished by where they occur: either inside a single thundercloud (intra-cloud), between two clouds (cloud-to-cloud), or between a cloud and the ground ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Cumulonimbus
Cumulonimbus (from Latin ''cumulus'', "heaped" and ''nimbus'', "rainstorm") is a dense, towering vertical cloud, typically forming from water vapor condensing in the lower troposphere that builds upward carried by powerful buoyant air currents. Above the lower portions of the cumulonimbus the water vapor becomes ice crystals, such as snow and graupel, the interaction of which can lead to hail and to lightning formation, respectively. When occurring as a thunderstorm these clouds may be referred to as thunderheads. Cumulonimbus can form alone, in clusters, or along squall lines. These clouds are capable of producing lightning and other dangerous severe weather, such as tornadoes, hazardous winds, and large hailstones. Cumulonimbus progress from overdeveloped cumulus congestus clouds and may further develop as part of a supercell. Cumulonimbus is abbreviated Cb. Appearance Towering cumulonimbus clouds are typically accompanied by smaller cumulus clouds. The cumulonimbus base ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Tornado
A tornado is a violently rotating column of air that is in contact with both the surface of the 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. Tornadoes come in many shapes and sizes, and they are often visible in the form of a 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 most extreme tornadoes can attain wind speeds of more than , are more than in diameter, and stay on the ground for more than 100&nb ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Dry Thunderstorm
A dry thunderstorm is a thunderstorm that produces thunder and lightning, but where most of its precipitation evaporates before reaching the ground. Dry lightning refers to lightning strikes occurring in this situation. Both are so common in the American West that they are sometimes used interchangeably. Dry thunderstorms occur essentially in dry conditions, and their lightning is a major cause of wildfires. Because of that, the National Weather Service, and other agencies around the world, issue forecasts for its likelihood over large areas. Where dry thunderstorms occur Dry thunderstorms generally occur in deserts or places where the lower layers of the atmosphere usually contain little water vapor. Any precipitation that falls from elevated thunderstorms can be entirely evaporated as it falls through the lower dry layers. They are common during the summer months across much of western North America and other arid areas. The shaft of precipitation that can be seen falling fro ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Hail
Hail is a form of solid precipitation. It is distinct from ice pellets (American English "sleet"), though the two are often confused. It consists of balls or irregular lumps of ice, each of which is called a hailstone. Ice pellets generally fall in cold weather, while hail growth is greatly inhibited during low surface temperatures. Unlike other forms of water ice precipitation, such as graupel (which is made of rime ice), ice pellets (which are smaller and translucent), and snow (which consists of tiny, delicately crystalline flakes or needles), hailstones usually measure between and in diameter. The METAR reporting code for hail or greater is GR, while smaller hailstones and graupel are coded GS. Hail is possible within most thunderstorms (as it is produced by cumulonimbus), as well as within of the parent storm. Hail formation requires environments of strong, upward motion of air within the parent thunderstorm (similar to tornadoes) and lowered heights of the freezing ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Storm
A storm is any disturbed state of the natural environment or the atmosphere of an astronomical body. It may be marked by significant disruptions to normal conditions such as strong wind, tornadoes, hail, thunder and lightning (a thunderstorm), heavy precipitation ( snowstorm, rainstorm), heavy freezing rain (ice storm), strong winds (tropical cyclone, windstorm), wind transporting some substance through the atmosphere such as in a dust storm, among other forms of severe weather. Storms have the potential to harm lives and property via storm surge, heavy rain or snow causing flooding or road impassibility, lightning, wildfires, and vertical and horizontal wind shear. Systems with significant rainfall and duration help alleviate drought in places they move through. Heavy snowfall can allow special recreational activities to take place which would not be possible otherwise, such as skiing and snowmobiling. The English word comes from Proto-Germanic ''*sturmaz'' meaning "noise, ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Thunderstorm Training
In meteorology, training denotes repeated areas of rain, typically associated with thunderstorms, that move over the same region in a relatively short period of time. Training thunderstorms are capable of producing excessive rainfall totals, often causing flash flooding. The name ''training'' is derived from how a train and its cars travel along a track (moving along a single path), without the track moving. Formation Showers and thunderstorms along thunderstorm trains usually develop in one area of stationary instability, and are advanced along a single path by prevailing winds. Additional showers and storms can also develop when the gust front from a storm collides with warmer air outside of the storm. The same process repeats in the new storms, until overall conditions in the surrounding atmosphere become too stable for support of thunderstorm activity. Showers and storms can also develop along stationary fronts A stationary front (or quasi-stationary front) is a weath ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Wind Shear
Wind shear (or windshear), sometimes referred to as wind gradient, is a difference in wind speed and/or direction over a relatively short distance in the atmosphere. Atmospheric wind shear is normally described as either vertical or horizontal wind shear. Vertical wind shear is a change in wind speed or direction with a change in altitude. Horizontal wind shear is a change in wind speed with a change in lateral position for a given altitude. Wind shear is a microscale meteorological phenomenon occurring over a very small distance, but it can be associated with mesoscale or synoptic scale weather features such as squall lines and cold fronts. It is commonly observed near microbursts and downbursts caused by thunderstorms, fronts, areas of locally higher low-level winds referred to as low-level jets, near mountains, radiation inversions that occur due to clear skies and calm winds, buildings, wind turbines, and sailboats. Wind shear has significant effects on the control ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Summer Thunderstorm In The Woods
Summer is the hottest of the four temperate seasons, occurring after spring and before autumn. At or centred on the summer solstice, the earliest sunrise and latest sunset occurs, daylight hours are longest and dark hours are shortest, with day length decreasing as the season progresses after the solstice. The date of the beginning of summer varies according to climate, tradition, and culture. When it is summer in the Northern Hemisphere, it is winter in the Southern Hemisphere, and vice versa. Timing From an astronomical view, the equinoxes and solstices would be the middle of the respective seasons, but sometimes astronomical summer is defined as starting at the solstice, the time of maximal insolation, often identified with the 21st day of June or December. By solar reckoning, summer instead starts on May Day and the summer solstice is Midsummer. A variable seasonal lag means that the meteorological centre of the season, which is based on average temperature patt ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Downdraft
In meteorology, an updraft is a small-scale current of rising air, often within a cloud. Overview Localized regions of warm or cool air will exhibit vertical movement. A mass of warm air will typically be less dense than the surrounding region, and so will rise until it reaches air that is either warmer or less dense than itself. The converse will occur for a mass of cool air, and is known as subsidence. This movement of large volumes of air, especially when regions of hot, wet air rise, can create large clouds, and is the central source of thunderstorms. Drafts can also be conceived by low or high pressure regions. A low pressure region will attract air from the surrounding area, which will move towards the center and then rise, creating an updraft. A high pressure region will attract air from the surrounding area, which will move towards the center and sink, spawning a downdraft. Updrafts and downdrafts, along with wind shear in general, are a major contributor to airplane cra ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Thundersnow
Thundersnow, also known as a winter thunderstorm or a thundersnowstorm, is a kind of thunderstorm with snow falling as the primary precipitation instead of rain. It is considered a rare and unusual phenomenon. It typically falls in regions of strong upward motion within the cold sector of an extratropical cyclone. Thermodynamically, it is not different from any other type of thunderstorm, but the top of the cumulonimbus cloud is usually quite low. In addition to snow, graupel or hail may fall as well. And the heavy snowfall tends to muffle the sound of the thunder so that it sounds more like a low rumble than the loud, sharp bang that you hear during regular thunderstorms. There are usually three causes of thundersnow such as a normal snowstorm that sustains strong vertical mixing which allows for favourable conditions for lightning and thunder to occur. It can also occur from the lake effect or ocean effect thunderstorm which is produced by cold air passing over relatively war ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]