What Are Whimsical Facts About Snowflakes?

How Do Snowflakes Form? 1 of 8

Snow crystals can only form when the air temperature is below freezing. Water vapor in a cloud forms a crystal around a nucleus of some sort of particle, usually dust. As the crystal grows, it eventually gets large enough to begin to fall to earth. The individual crystals bump into each other as they fall and form larger flakes.