Nimbus clouds Nimbus clouds are ram clouds of uniform grayness that extend over the entire sky Cumulonimbus clouds Cumulonimbus is the cloud formation resulting from a cumulus cloud building up, extending to great heights, and forming in the shape of an anvil. You can expect a thunderstorm if this cloud is moving in your direction. Cirrostratus clouds Cirrostratus is a fairly uniform layer of high stratus clouds that are darker than cirrus clouds. Cirrostratus clouds indicate good weather. Cirrocumulus clouds Cirrocumulus is a small, white, round cloud at a high altitude.
Cirrocumulus clouds indicate good weather.