What characterizes the cumulus stage of a thunderstorm?

The cumulus stage of a thunderstorm is primarily characterized by strong updrafts. During this initial phase, warm, moist air rises rapidly, leading to the formation of cumulus clouds. As this warm air ascends, it cools and condenses, which is essential for the development of a thunderstorm. The updrafts create significant vertical growth in the clouds, which eventually may lead to further stages of the thunderstorm if conditions are right.

The strong updrafts are crucial as they continue to feed the storm with moisture, allowing it to develop and grow. The overall structure of the storm is still relatively weak at this point compared to later stages, and while there may be some formation of cloud structures, it is the strong updrafts that define the cumulus stage.

Other options do reflect aspects that could be present in various storm stages, but they do not specifically capture the essence of the cumulus stage, which is dominated by the vigorous updrafts that signify the storm's early development.