Which cloud type is often indicative of severe weather?

Cumulonimbus clouds are often indicative of severe weather due to their towering structure and vertical development. These clouds are associated with thunderstorms, heavy precipitation, and severe phenomena such as hail, tornadoes, and lightning. The intense updrafts within cumulonimbus clouds allow for the formation of various severe weather conditions, reflecting their role in the most violent weather events.

Other cloud types do not typically exhibit the same characteristics associated with severe weather. For example, cumulus clouds are generally fair-weather clouds, while stratus clouds are more associated with overcast skies and light drizzle. Cirrus clouds, although they can indicate changes in the weather, are high-altitude clouds that usually signal fair weather rather than severe conditions. Thus, cumulonimbus clouds stand out as the primary indicator of severe weather in the atmosphere.