What moisture in a cloud is heavy enough to fall back to Earth?

The moisture in a cloud that is heavy enough to fall back to Earth primarily consists of water droplets or ice crystals that have coalesced to form larger particles. When these droplets grow to a size of about 0.5 millimeters or more, they become heavy enough to overcome the updrafts in the cloud and begin to fall as precipitation, such as rain or snow. This process is influenced by factors like temperature, humidity, and cloud dynamics.