What does "CB" represent in meteorological terms?

In meteorological terms, "CB" stands for Cumulonimbus cloud. These clouds are significant because they are associated with severe weather phenomena, including thunderstorms, heavy rain, lightning, and even tornadoes. Cumulonimbus clouds are vertically developed and can extend through multiple layers of the atmosphere, making them a critical focus for meteorologists and air traffic controllers. They indicate instability in the atmosphere and are often a key factor in flight safety, as they can lead to turbulent conditions. Understanding and recognizing Cumulonimbus clouds helps ATC trainees and pilots prepare for and respond to potential weather-related challenges during flight operations.