As the temperature decreases the molecules lose some of their energy, and compress onto particles in the atmosphere, shaping clouds.
Water molecules are stored in the atmosphere in all three states of matter. Water vapor in the atmosphere is commonly referred to as humidity. If liquid and solid forms of water can overcome atmospheric updrafts they can fall to the Earth's surface as precipitation. The formation of ice crystals and water droplets occurs when the atmosphere is cooled to a temperature that causes condensation or deposition. Four processes that can trigger such atmospheric cooling are oro-graphic uplift; convectional uplift; air mass convergence; and energy loss.  Precipitation can be defined as any aqueous deposit, in liquid or solid form, that develops in a saturated atmospheric environment and generally falls from clouds. A number of different precipitation types have been classified by meteorologists including rain, freezing rain, snow, ice pellets, snow pellets, and hail. Fog represents the saturation of air near the ground surface. Classification of fog types is accomplished by the identification of the mechanism that caused the air to become saturated. ...Show more