The air must be moist.
before clouds can form air must become what?
condensationCondensation creates clouds. Clouds develop in an air mass that becomes saturated (relative humidity becomes 100%).Read more http://www.kgbanswers.com/in-what-process-must-occur-for-clouds-to-form/4008725#ixzz1EQ3cx57a
Cool air and dust Particles
clouds form when the air is cooled to its dew point
If there isn't enough moisture, then no clouds will form.
Cumulonimbus, or thunderstorm, clouds form from rising moist air.
Clouds form when warm moist air rises, cools and condenses.
Descending air not allow clouds to form because air rises at low pressures.
Descending air not allow clouds to form because air rises at low pressures.
clouds form above chimneys as the warm air mixes with the cool air
Clouds only form when the air pressure is low.
If there isn't enough moisture, then no clouds will form.