It depends on the kind of cloud.
Fog is a cloud that touches the ground, so the closest clouds get to the ground is to touch it.
High-level clouds are typically thin and white in appearance, but can appear in a magnificent array of colors when the sun is low on the horizon. Because of their lower altitudes, they are composed primarily of water droplets, however, they can also be composed of ice crystals when temperatures are cold enough. However, when temperatures are cold enough, these clouds may also contain ice particles and snow. Vertically Developed Clouds. Probably the most familiar of the classified clouds is the cumulus cloud.