As the warm, moist air moves upward, it cools, condenses,[5] and forms a cumulonimbus cloud that can reach heights of over 20 kilometres (12 mi).

Damage that results from thunderstorms is mainly inflicted by downburst winds, large hailstones, and flash flooding caused by heavy precipitation.

[7] Mesoscale convective systems formed by favorable vertical wind shear within the tropics and subtropics can be responsible for the development of hurricanes.

The moisture carried upward cools into liquid drops of water due to lower temperatures at high altitude, which appear as cumulus clouds.

If atmospheric conditions do not support super cellular development, this stage occurs rather quickly, approximately 20–30 minutes into the life of the thunderstorm.

Pulse severe storms are poorly organized and occur randomly in time and space, making them difficult to forecast.

They often arise from convective updrafts in or near mountain ranges and linear weather boundaries, such as strong cold fronts or troughs of low pressure.

[18] These storms can produce destructive tornadoes, extremely large hailstones (10 centimetres or 4 inches diameter), straight-line winds in excess of 130 km/h (81 mph), and flash floods.

[15] In the United States, a thunderstorm is classed as severe if winds reach at least 93 kilometres per hour (58 mph), hail is 25 millimetres (1 in) in diameter or larger, or if funnel clouds or tornadoes are reported.

[39] A mesoscale convective system's overall cloud and precipitation pattern may be round or linear in shape, and include weather systems such as tropical cyclones, squall lines, lake-effect snow events, polar lows, and mesoscale convective complexes (MCCs), and they generally form near weather fronts.

[41][42] Forms of MCS that develop in the tropics are found in use either the Intertropical Convergence Zone or monsoon troughs, generally within the warm season between spring and fall.

[43][44] One exception is that of lake-effect snow bands, which form due to cold air moving across relatively warm bodies of water, and occurs from fall through spring.

[46] Once the parent MCS dies, later thunderstorm development can occur in connection with its remnant mesoscale convective vortex (MCV).

[48] The two major ways thunderstorms move are via advection of the wind and propagation along outflow boundaries towards sources of greater heat and moisture.

If the gust front, or leading edge of the outflow boundary, races ahead of the thunderstorm, its motion will accelerate in tandem.

In Rapid City, South Dakota, in 1972, an unusual alignment of winds at various levels of the atmosphere combined to produce a continuously training set of cells that dropped an enormous quantity of rain upon the same area, resulting in devastating flash flooding.

In ecosystems, acid rain can dissolve plant tissues of vegetations and increase acidification process in bodies of water and in soil, resulting in deaths of marine and terrestrial organisms.

[62] One of the more common regions for large hail is across mountainous northern India, which reported one of the highest hail-related death tolls on record in 1888.

[66] Hail in this region occurs between the months of March and October during the afternoon and evening hours, with the bulk of the occurrences from May through September.

Hail can cause serious damage, notably to automobiles, aircraft, skylights, glass-roofed structures, livestock, and most commonly, farmers' crops.

Tornadoes come in many sizes but are typically in the form of a visible condensation funnel, whose narrow end touches the earth and is often encircled by a cloud of debris and dust.

[72] Most tornadoes have wind speeds between 40 and 110 mph (64 and 177 km/h), are approximately 75 metres (246 ft) across, and travel several kilometers (a few miles) before dissipating.

[76] Doppler radar data, photogrammetry, and ground swirl patterns (cycloidal marks) may also be analyzed to determine intensity and award a rating.

[77] Waterspouts have similar characteristics as tornadoes, characterized by a spiraling funnel-shaped wind current that form over bodies of water, connecting to large cumulonimbus clouds.

[90] Preparing the home by removing dead or rotting limbs and trees, which can be blown over in high winds, can also significantly reduce the risk of property damage and personal injury.

[95] Kampala and Tororo in Uganda have each been mentioned as the most thunderous places on Earth,[96] a claim also made for Singapore and Bogor on the Indonesian island of Java.

Thunderstorms are relatively uncommon along much of the West Coast of the United States,[99] but they occur with greater frequency in the inland areas, particularly the Sacramento and San Joaquin Valleys of California.

[16][failed verification] The Fermi Gamma-ray Burst Monitor results show that gamma rays and antimatter particles (positrons) can be generated in powerful thunderstorms.

The Norse considered thunderstorms to occur when Thor went to fight Jötnar, with the thunder and lightning being the effect of his strikes with the hammer Mjölnir.

[107] Thunderstorms, evidenced by flashes of lightning, on Jupiter have been detected and are associated with clouds where water may exist as both a liquid and ice, suggesting a mechanism similar to that on Earth.