Instrument Rating Checkride Practice Test

During the dissipating stage of a thunderstorm, the primary characteristic is that only downdrafts are present. This stage follows the mature stage, where the thunderstorm has reached its peak intensity with both strong updrafts and downdrafts contributing to its severity. As the storm begins to weaken, the updrafts diminish, leading to decreased precipitation and eventual dissipation of the storm's structure.

In the dissipating stage, the downdrafts become the dominant force. Without the significant updrafts that initially fueled the storm, the precipitation decreases, and the cloud structure starts to break down. This process results in the gradual fading away of the thunderstorm.

The other options refer to conditions not typical of the dissipating stage. In the dissipating stage, it is simply incorrect to indicate that both updrafts and downdrafts continue to coexist since the lack of sufficient updrafts means the storm is waning. The mention of a cyclone is misleading, as while thunderstorms can occasionally spawn cyclonic activity, a dissipating thunderstorm does not evolve into a cyclone. Thus, recognizing the exclusive presence of downdrafts during this final stage is key in understanding the lifecycle of a thunderstorm.