thunderstorm cell

...the height of a thundercloud, expressed as its distance from the ground, varies with latitude and season, but when expressed as the temperature at that level, thunderclouds commonly develop into the upper atmosphere, where the temperature is -20°C or even colder.
[Structure of thunderclouds, thunderstorm cells]
A thundercloud is a group of clouds made up of thunderstorm cells, each of which is a convective cloud with a diameter of 3 to 5 km, consisting of a pair of ascending and descending air currents. It is an extremely short-lived meteorological phenomenon with a lifespan of about 45 minutes, going through stages of infancy, adulthood, and old age. In the adult stage, the updrafts become even stronger, causing large hailstones to form at the top of the cloud, which are then dragged down by their violent falling motion, creating a downdraft, forming the pair of ascending and descending air currents shown in Figure 1.

*Some of the terminology that mentions "Thunderstorm Cell" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…雷雲の高さを地表からの距離で表すと，緯度と季節でまちまちになるが，高さをそのレベルの気温で表すと，雷雲は共通して－20℃あるいはさらに気温の低い上層まで発達している。
［雷雲の構造，雷雨細胞］
　雷雲は雷雨細胞(雷雨セル)thunderstorm cellからなる雲の集団であり，単位となっている細胞は，上昇と下降の気流の対からなる直径3～5kmの対流雲で，幼年期，成年期，老年期という経過をたどる寿命45分程度のきわめて短命の気象現象である。幼年期の雲は，多量に水蒸気を含む下層大気の上昇でつくられ，成年期では上昇気流がいっそう強まり，雲の上部に大粒のひょうが形成され，その激しい落下運動にひきずられて下降気流が生じ，図1に示す上昇，下降の気流の対ができる。…

※「thunderstorm cell」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報