Which type of cloud is indicative of severe turbulence and thunderstorms?

Cumulonimbus clouds are characterized by their towering structure and vertical development, often reaching significant heights in the atmosphere. These clouds are associated with severe weather conditions, including thunderstorms, heavy precipitation, and strong turbulence. The formation of cumulonimbus clouds involves intense upward air currents and can lead to phenomena such as lightning, hail, and tornadoes.

The presence of cumulonimbus clouds signifies unstable atmospheric conditions, which are conducive to severe turbulence. Pilots and meteorologists closely monitor these clouds due to their potential for rapid changes in weather, including downdrafts and updrafts that can create hazardous flying conditions. This visibility into the cloud's structure and its associated weather patterns makes it a clear indicator of severe turbulence and thunderstorms.

Other cloud types listed, such as stratus, cirrus, and nimbostratus, do not exhibit the same characteristics linked to severe weather. Stratus clouds typically produce overcast conditions with light precipitation but are not associated with turbulence. Cirrus clouds are high-altitude clouds that indicate fair weather but do not signify severe conditions. Nimbostratus clouds can produce steady, moderate precipitation, but they generally do not lead to turbulence as severe as that associated with cumulonimbus clouds.