High-level clouds - typically 5-13 km above sea level - higher in low latitudes, lower in high latitudes.

• Cirrus - very high, white, wispy.
• Cirrocumulus - very high, white,small.
• Cirrostratus - very high, white, wispy, form a halo around the sun or moon.

Medium level clouds - typically 2-7 km above the ground

• Altostratus - white or grey, layers, sun only faintly seen.
• Altocumulus - white or light grey, rippled, dappled or in small rolls or cells.

Low level clouds - cloud base (the bottom of the cloud) is below 3 km although the top of cumulonimbus cloud can reach 19,000 m.

• Stratus - low, white or grey, no rain.
• Stratocumulus - low, grey or whitish, sheets or patches of cloud in the form of rolls,lumps or rounded masses.
• Cumulus - low, white, fluffy, heaped.
• Cumulonimbus - low to high, vertical, dark, rain.
• Nimbostratus - low, dark, heavy rain or even snow.