Stratus - Stratus clouds are low level clouds that are flat and tend to cover much of the sky. Nimbostratus - These are thick, dark gray middle level to low level clouds. Altocumulus - Middle level clouds that are small, white, and puffy.Ħ. Altostratus - Medium level clouds that form a dark gray covering. These clouds signal that it may rain in the next day or so.Ĥ. Cirrostratus - High, flat clouds that might cover the sky making it appear overcast. Cirrocumulus - These are high clouds that look like tiny cotton balls bunched together.ģ. Cirrus - Cirrus clouds are high level clouds that are thin and wispy. Middle cloud - altostratus, altocumulus, nimbostratusġ.High cloud - cirrus, cirrocumulus, cirrostratus.Meteorologists combine cloud characteristics and levels to get the ten main cloud types: Vertical clouds usually have the word 'cumulus' in their name. These clouds are very tall and may span many of the cloud levels. Vertical - Some clouds are vertical clouds.Low level clouds usually have the word 'stratus' in their name. They are often composed of mostly water droplets. Low - Low level clouds form below 6,500 feet.Medium level clouds usually have the word 'alto' in their name. They may be made up of water droplets or ice crystals. Middle - Middle level clouds form between 6,500 and 20,000 feet high.High level clouds usually have the prefix 'cirro' or 'cirrus' in their name. Because it is colder higher up, these clouds are mostly made of ice crystals. High - High level clouds form above 20,000 feet.

There are high, middle, and low level clouds. As more and more air cools down, more droplets form and they eventually become a cloud.Ĭlouds are often described by the level or elevation where they form.

As warm air cools the water vapor turns into tiny droplets of water or ice. All air contains some water vapor and warm air can hold more water vapor than cold air. Most clouds form as warm air rises in the atmosphere and cools down.

Cirrus clouds weather