1 Answer

Clouds are the result of air being lifted (or simply rising) to the level where condensation takes place. Air contains water vapor, and as air rises it cools. If the air cools enough the water vapor in that air begins to condense and form tiny water droplets (or tiny ice crystals if the air is real cold), which is what a cloud is. The level that this occurs depends on the initial temperature of the rising air and how much water vapor was in it. Drier air has to rise higher in order for it to cool enough to start condensation, as opposed to air that is more moist, thus the differing levels you have noticed. Also, clouds at differing levels can be blown in by the winds in the atmosphere.

country bumpkin

No, but I seem to have my head stuck high in the clouds these days.