How Do Snowflakes Form?

A blizzard creates a blanket of snow. Look closer and the true beauty of individual snowflakes can be seen. How are different shapes of snowflakes formed and why are they always perfectly symmetrical? Chemistry - Atoms And Bonding - Learning Points. Snowflakes form from water vapor in clouds when the temperature is zero degrees Celsius or lower. Temperature, humidity and altitude affect the type of snowflakes that form. Snowflakes are symmetrical because of the arrangement of water molecules in ice. When different types of snowflakes lie on top of one another, the snow will be unstable and an avalanche can occur. A Twig Context Film. Reinforce and extend the learning required by the curriculum. Twig’s context films show abstract concepts in action in the real world.