Thunderstorms, also known as electrical or lightning storms, are characterized by lightning and thunder. They form in cumulonimbus clouds and are often accompanied by strong winds, heavy rain, and sometimes snow, sleet, or hail. Some thunderstorms produce little to no precipitation. They can form lines or rainbands called squall lines. Severe thunderstorms can produce dangerous weather phenomena like large hail, strong winds, and tornadoes. Supercells, a type of severe thunderstorm, rotate like cyclones. Most thunderstorms move with the wind, but vertical wind shear can cause them to deviate from this path.
In 1945, it was noted that the energy released by a typical thunderstorm is comparable to that of a tropical cyclone and exceeds the energy released during the atomic bomb blast in Hiroshima, Japan. This highlights the immense power of thunderstorms.
In 1972, Rapid City, South Dakota, was struck by significant flash flooding caused by a back-building thunderstorm. An unusual alignment of atmospheric winds led to a series of storms that repeatedly hit the same area, resulting in severe flooding and damage.
In 2003, Aurora, Nebraska, witnessed the fall of the largest hailstone ever recorded in the United States in terms of circumference and length. Such hailstones present significant hazards to structures and aircraft, demonstrating the destructive nature of hail associated with thunderstorms.
On 16 August 2004, a back-building thunderstorm caused significant flooding in Boscastle, England. This rare meteorological event involved storms that continuously developed on the upwind side, leading to intense rainfall in a localized area, causing catastrophic flash flooding.
In 2008, the National Weather Service stopped recommending the 'lightning crouch' as a protective measure during thunderstorms. This decision was made because the posture does not effectively reduce the risk of injury or death from nearby lightning strikes.
On 1 December 2015, Chennai experienced devastating flooding due to a back-building thunderstorm. The weather conditions led to continuous rainfall over the city, highlighting the destructive potential of such storms.