If the cooling process which gives rise to cloud formation is continued, the droplets of which the cloud consists grow in size until they become too heavy to remain suspended in the air and they fall to the ground as rain. The longer the droplets are held aloft by the updrafts of wind in the clouds, the larger the drops become and the heavier the rain.

Hail is caused by the large raindrops being carried above freezing levels where they grow into balls of ice and eventually fall to the ground.

If the temperature at which condensation actually takes place is below freezing point, the droplets form ice crystals, which grow and become snow flakes