It rains because water vapor in the air cools and condenses into tiny droplets to form clouds. When these droplets grow large and heavy enough, they fall to the ground as rain. This process happens as part of the water cycle, which includes evaporation of water from the Earth's surface, condensation in the atmosphere, and precipitation. Warm air holds more moisture, and when it rises and cools, the moisture condenses and forms rain. Different types of rain occur depending on how the air rises and cools, including relief rain (over mountains), convectional rain (due to heating by the sun), and frontal rain (when warm air is pushed over cold air).
