What causes rain?
You know rain falls from clouds. Have you ever wondered how raindrops happen to be in clouds?
Moisture is constantly evaporated from the earth’s surface by the warmth of the sun. the invisible water vapor is carried upward by currents of warm, rising air. As the moisture-loaded air rises it cools.
As the air cools, the amount of moisture, it can hold decreases. If the cooling continues long enough, some of the water vapor condenses into tiny droplets of water, which collects to form the clouds we see in the sky. The droplets are so light that the clouds we see in the sky on currents of air.
As the air grows colder, more and more water vapor is changed into water droplets. The droplets grow bigger as they collect more moisture. Then the clouds may become thick rain clouds that darken the sky.
Finally, the water drops become so heavy that they fall as rain. – Dick Rogers