Clouds Formation Before The Storm

Family D2 includes:
- Genus Cumulonimbus (Cb): Heavy towering masses of free convective cloud with dark grey to nearly black bases that are associated with thunderstorms and showers. Thunderstorms can produce a range of severe weather that includes hail, tornadoes, a variety of other localized strong wind events, several types of lightning, and local very heavy downpours of rain that can cause flash floods, although lightning is the only one of these that requires a thunderstorm to be taking place. Generally, cumulonimbus require moisture, an unstable air mass, and a lifting force (heat) in order to form. Cumulonimbus typically go through three stages: the developing stage, the mature stage, and the dissipation stage. The average thunderstorm has a 24 km (15 mi) diameter. Depending on the conditions present in the atmosphere, these three stages take an average of 30 minutes to go through.
+ Species Cumulonimbus calvus (Cb cal): Cumulonimbus clouds with very high clear-cut domed tops similar to towering cumulus.
+ Species Cumulonimbus capillatus (Cb cap): Cumulonimbus clouds with very high tops that have become fibrous due to the presence of ice crystals.