Instrument Rating Checkride Practice Test

During which stage of a thunderstorm does rainfall begin?

1. Cumulus stage

2. Mature stage

3. Dissipating stage

4. Initial stage

The correct answer is: Mature stage

Rainfall begins during the mature stage of a thunderstorm. This stage is characterized by the presence of a fully developed cumulonimbus cloud, which can reach significant heights and lead to intense weather phenomena. During this phase, updrafts are strong, and as water vapor condenses within the cloud, it forms precipitation. The mature stage also typically features distinct features like heavy rain, thunderstorms, lightning, and potentially hail. While rainfall can occur in other stages, it's during the mature stage that it is most significant and begins in earnest as the storm reaches its peak intensity. In the cumulus stage, the storm is just developing, with only updrafts and no precipitation. The dissipating stage follows the mature stage, where the storm weakens, and rainfall becomes lighter. The initial stage, similarly to the cumulus stage, does not produce rainfall as it is still in the formation phase. Thus, recognizing the characteristics of these stages helps one understand the dynamics of thunderstorm progression.