What type of weather is typically associated with cumulus clouds?

Cumulus clouds are often associated with instability in the atmosphere, which can lead to the development of severe weather conditions, including thunderstorms. These clouds typically form when warm, moist air rises and cools, creating a buoyant effect that can lead to the growth of the clouds. As these clouds develop vertically, they can indicate that the atmosphere is conducive to instability.

In moderate cases, cumulus clouds can grow into cumulonimbus clouds, which are responsible for severe thunderstorms, heavy rainfall, hail, and even tornadoes. The presence of cumulus clouds indicates that rising air currents and moisture are present, making them a key indicator of potential instability and storm development.

The other options suggest conditions that do not align with the characteristics of cumulus clouds. Calm and stable weather would generally not allow for the development of cumulus clouds, while mild and cloudy conditions may exist without the dynamic processes associated with cumulus development. Clear and calm weather, likewise, does not foster the rise of warm air necessary for cumulus formation. Thus, the association of cumulus clouds with severe thunderstorms and instability is crucial to understanding their significance in meteorology.