The type of clouds that create thunderstorms, lightning, and occasionally tornadoes are called cumulonimbus clouds. These clouds are characterized by their towering, anvil-shaped appearance and are formed by the intense updrafts and downdrafts of air that occur during a thunderstorm.

Cumulonimbus clouds can reach heights of several miles and are capable of producing heavy rainfall, hail, and strong winds. They are also associated with lightning and thunder, which are produced when the electrical charges in the cloud build up and eventually discharge. In some cases, cumulonimbus clouds can also produce tornadoes, which are violently rotating columns of air that extend from the base of the cloud to the ground.