Nimbostratus Clouds
Less than 10,000 feet above the earth, nimbostratus clouds are dark and form an even sheet-like layer in the sky. This cloud formation often produces snow or rain that falls continuously for several hours. While nimbostratus clouds typically do not produce heavy precipitation, light to moderate rain or snow is possible. When the fog lifts in the morning, the leftover clouds are stratus clouds. Even though the clouds look like they could produce rain, if they dissipate quickly enough, the day will stay clear.
Stratocumulus Clouds
Stratocumulus clouds look like dark gray and white cotton balls in the sky. They are rolling clouds that dot the atmosphere. These clouds gather below 10,000 feet and are very thin. Stratocumulus clouds generally drift away by evening and usually produce no precipitation. If such clouds do produce moisture, it is a light rain or drizzle that does not last very long.
Altostratus Clouds
When you look up in the sky and see thin, gray-blue clouds, you are seeing altostratus clouds. Altostratus clouds give a veiled illusion to the sun or moon, but often the light shines hazily through the clouds. Altostratus clouds hang between 10,000 to 20,000 feet above the ground and are known as middle clouds. When you see these clouds, a storm is forming and precipitation generally follows.
Cirrostratus
The thin white clouds you observe high up in the sky are cirrostratus clouds. These clouds are more than 20,000 feet above the ground and often produce a halo effect around the sun. Cirrostratus clouds consist of ice crystals. They do not produce rain or snow, but often indicate a storm or weather event is forming nearby.