Which cloud type is primarily associated with rain?

Cumulonimbus clouds are primarily associated with rain because they are towering, vertical clouds that develop in a convective environment. These clouds can reach great heights in the atmosphere and are typically indicative of severe weather conditions. As they grow, they contain a significant amount of moisture, which eventually leads to precipitation in the form of rain, and they can also produce thunderstorms, hail, and even tornadoes.

In contrast, cirrus clouds are high-altitude clouds that are thin and wispy, not typically associated with precipitation. Cumulus clouds are puffy and indicate fair weather; while they can develop into larger clouds capable of producing rain, they do not inherently bring rain on their own. Stratus clouds appear as uniform gray layers covering the sky and can produce light drizzle, but they are generally less intense in their precipitation compared to cumulonimbus clouds. Thus, cumulonimbus is the cloud type that most directly correlates with significant rain events.