A dark cloud of great vertical extent charged with electricity; associated with thunderstorms.
1The surrounding hills still have their forests; cumulonimbus clouds towering over them like clenched fists.
2Specifically, the scientists were looking at the temperatures at the very tops of each storm's cumulonimbus clouds.
3Cumulonimbus Clouds Super fluffy, cotton-like balls, shaped into an anvil, are a harbinger for lightning, hail, and tornadoes.
4During one of these flights, small fluctuations were observed in the vicinity of the aircraft with formation of Cumulonimbus clouds.
5And we also know the process occurs most spectacularly in the large towering cumulonimbus clouds that we associate with thundery conditions.
6They realised that tropical cumulonimbus clouds could tower to 15km tall, so high they reached the top of the lower atmosphere.
7The hot air rises and dense cumulonimbus clouds form as towering plumes reaching up to 12 km (39,000 ft) high.