https://doi.org/10.1351/goldbook.C01441
Heavy masses of dense cloud whose cumuliform summits rise in the forms of towers, the upper parts having a fibrous texture and often spreading out into the shape of an anvil; these clouds generally produce showers of rain and sometimes of snow, hail or soft hail, and often develop into thunderstorms; up to \(12\ 000\ \text{m}\); summits may be as cold as \(-50\ ^{\,\unicode{x26ac}}\text{C}\); strong convective motions with vertical velocities of \(3\) to greater than \(30\ \text{m s}^{-1}\).