Definition
A cumulonimbus cloud is a tall, dense, towering vertical cloud associated with thunderstorms and severe weather. Imagine it as the king of storm clouds, big and powerful. It's characterized by a dark, ominous base and often an anvil-shaped top. These clouds can produce heavy rain, hail, lightning, and even tornadoes. They form in unstable atmospheric conditions with plenty of moisture. They are a dramatic display of nature's power.