Which phase of a thunderstorm is characterized by updraft and typically occurs within the first 15 minutes?

The phase characterized by significant updrafts and occurring within the initial 15 minutes of a thunderstorm is known as the cumulus phase. During this stage, warm air rises and cools, leading to the formation of cumulus clouds. The development of these clouds is a critical process, as the strong updrafts can eventually lead to the formation of larger storm systems.

The cumulus phase is essential because it sets the foundation for the later stages of the thunderstorm, including the mature phase, where precipitation and downdrafts become more prominent. Understanding this initial phase helps pilots and meteorologists predict storm development and behavior, which is crucial for safety and operational decision-making.