Cumulonimbus

Cumulonimbus clouds are the clouds associated with thunderstorms. Clouds of the nimbus category are those producing rain, produced by an updraft through the moisture of a cloud. Nimbostratus are associated with rain that covers a vast area, but cumulonimbus are discrete, independent clouds featuring a particularly strong updraft, which can at times reach the tropopause, giving the appearance of an anvil when storms are strongest.

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