The World Meteorological Organization's International Cloud Atlas defines a cloud as a hydrometeor consisting of minute particles of liquid water or ice, or both, suspended in the free air and usually not touching the ground. It may also include larger particles of liquid water or ice as well as non-aqueous liquid or solid particles such as those present in fumes, smoke, or dust. Fog and mist conform to the above definition of a cloud, but they are not classified or reported as such. Fog may be thought of as a cloud which touches the surface of the earth.
The following sections of CLOUDS (8NhCLCMCH) contain detailed information on the appropriate title:
Coding 8NhCLCMCH on the Meteorological Log
Priority of Reporting for CL Clouds
Priority of Reporting for CM Clouds
Priority of Reporting for CH Clouds
Description of the Cloud Types
Hints on Observing Cloud Types
Hints on Estimating Height of CL Clouds