Stratus (0- 6,500ft) Stratus clouds are very low level grey layers or patches of clouds with fuzzy edges. They can be accompanied by drizzle, snow or snow grains.
Altocumulus (2,000-18,000ft) Small layers or patches of clouds called "cloudlets." Found in settled weather, they can make droplets and contain ice crystals.
Altostratus (7,000-18,000ft) Large thin gray or blue clouds. Composed of water droplets and ice crystals. You can also see the sun peak through sometimes.
Cirrus (18,000-40,000ft) Short detached, hair like clouds found in high altitudes. During sunsets and sunrises, these clouds can take the colors of the sun.