Kumulonimbusz

Kumulonimbusz is a term used in some languages or texts as a variant spelling of cumulonimbus, referring to the same class of tall, vertically developed convective clouds that produce thunderstorms. Cumulonimbusz form from strong convection that lifts warm, moist air from near the surface. As air ascends, the water vapor condenses, releasing latent heat that fuels further updrafts.

The base of the cloud is typically a few hundred meters to a couple of kilometers above the ground, while the upper part can extend through the troposphere, sometimes reaching 12 to 15 kilometers or more, especially in tropical regions. The cloud often develops from a cumulus congestus and can grow into a recognizably anvil-shaped top known as the incus when upper-level winds spread the cloud's upper portions.

In the mature stage, the cloud contains heavy precipitation, strong winds, lightning, and sometimes hail or tornadoes. Downdrafts and gust fronts accompany the rain, producing rapid changes in wind and sometimes microbursts. The dissipating stage occurs as the updraft weakens and the cloud loses its moisture and instability.

Hazards associated with kumulonimbusz include severe turbulence, icing, lightning, heavy rainfall with flash flooding, hail, and, in some cases, tornado development. They pose significant risks to aviation and outdoor activities. Weather forecasting uses satellite imagery, radar, and atmospheric stability indices to identify potential cumulonimbus development and issue warnings.