Cumulonimbus clouds are primarily associated with stormy weather. These towering clouds can reach great heights and are characterized by their anvil-shaped tops. They usually form during thunderstorms and can produce severe weather conditions such as heavy rain, lightning, hail, and even tornadoes. Cumulonimbus clouds are capable of developing into severe storms due to their ability to hold significant moisture and energy in the atmosphere. Their rapid vertical development indicates unstable atmospheric conditions, making them a key player in intense weather phenomena.