There are four major groupings of clouds based on their position. High-level clouds form above 20,000 feet (6,000 meters) and since the temperatures are so cold at such high elevations, these clouds are primarily composed of ice crystals. High-level clouds are typically thin, wispy, and white in appearance. Cloud types include cirrus and cirrostratus.

Mid level clouds typically appear between 6,500 to 20,000 feet (2,000 to 6,000 meters). Because of their lower altitudes, they are composed primarily of water droplets, however, they can also be composed of ice crystals when temperatures are cold enough. Cloud types include altocumulus and altostratus.

Low clouds are composed of water droplets since their bases generally lie below 6,500 feet (2,000 meters). However, when temperatures are cold enough, these clouds may also contain ice particles and snow. Cloud types include nimbostratus and stratocumulus.

Vertically Developed Clouds are created commonly through either thermal convection or frontal lifting. These clouds can grow to heights in excess of 39,000 feet (12,000 meters). Cloud types include fair weather cumulus and cumulonimbus.