Cloud Types
Fog: Ground-level clouds similar to stratus clouds.
Stratus: Flat, uniform clouds that form below 7,000 ft (2 km) above sea level. Stratus clouds can sometimes cause light rainfall.
Stratocumulus: Clouds made of groups of round masses located below 7,000 ft (2 km). They sometimes cause light rain or snow.
Cumulus: Flat-based, heap-shaped clouds are located below 7,000 ft (2 km). They rarely cause precipitation.
Altostratus: Flat, uniform clouds that form between 7,000 and 23,000 ft (2–7 km) above sea level and rarely cause precipitation.
Altocumulus: Heap-shaped clouds that form between 7,000 and 23,000 ft (2–7 km) above sea level.
Cirrostratus: Flat, thin clouds that form between 20,000 and 43,000 ft (6–13 km). They do not cause precipitation.
Cirrus: Thin, wispy clouds that form between 16,500 and 45,000 ft (5–14 km). They do not cause precipitation.
Cirrocumulus: Small, patched clouds that form between 16,000 and 49,000 ft (5–15 km). They usually do not cause precipitation.
Polar Stratospheric Clouds (PSC): Colorful, glowing clouds that only form in the polar regions. They form in the stratosphere at heights of 49,000–82,000 ft (15–25 km).
Noctilucent Clouds: Clouds made of ice crystals that are only visible in the polar regions during twilight. They form in the mesosphere at heights of between 250,000 and 280,000 ft (76 to 85 km) and only form at temperatures below –184 °F (-120 °C).
Stratus: Flat, uniform clouds that form below 7,000 ft (2 km) above sea level. Stratus clouds can sometimes cause light rainfall.
Stratocumulus: Clouds made of groups of round masses located below 7,000 ft (2 km). They sometimes cause light rain or snow.
Cumulus: Flat-based, heap-shaped clouds are located below 7,000 ft (2 km). They rarely cause precipitation.
Altostratus: Flat, uniform clouds that form between 7,000 and 23,000 ft (2–7 km) above sea level and rarely cause precipitation.
Altocumulus: Heap-shaped clouds that form between 7,000 and 23,000 ft (2–7 km) above sea level.
Cirrostratus: Flat, thin clouds that form between 20,000 and 43,000 ft (6–13 km). They do not cause precipitation.
Cirrus: Thin, wispy clouds that form between 16,500 and 45,000 ft (5–14 km). They do not cause precipitation.
Cirrocumulus: Small, patched clouds that form between 16,000 and 49,000 ft (5–15 km). They usually do not cause precipitation.
Polar Stratospheric Clouds (PSC): Colorful, glowing clouds that only form in the polar regions. They form in the stratosphere at heights of 49,000–82,000 ft (15–25 km).
Noctilucent Clouds: Clouds made of ice crystals that are only visible in the polar regions during twilight. They form in the mesosphere at heights of between 250,000 and 280,000 ft (76 to 85 km) and only form at temperatures below –184 °F (-120 °C).