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5. Mature Stage

a. The mature stage begins when drops are thrown out from the updrafts, or they
become so large that the updraft can no longer hold them or lift them upward, and the drops
begin to fall. This occurs approximately 10-15 minutes after the cloud has built upward above
the freezing level.

b. As the raindrops fall they pull air with them. This is a major factor in the formation
of downdrafts which characterize a thunderstorm in the mature stage.

c. The air being pulled downward by the falling rain is cooler than the surrounding
air, and the pull caused by the falling raindrops speeds up its downward movement. Throughout
the mature stage, downdrafts continue to develop and exist at the same time as the updrafts.