Puffy, white clouds that have flat bottoms. Cumulus clouds form when warm air rises. When these clouds get larger, they produce thunderstorms. Clouds that have "nimbus" in their name are likely to produce precipitation.
These are clouds that are formed in layers. Stratus clouds cover areas and can often block out the sun. Fog is a stratus cloud that has formed near the ground.
Cirrus clouds are thin, feathery, white clouds found at high altitudes. They form when the wind is strong. If they get thicker, cirrus cloudsmay show that a change in the weather is coming.