How is snow made?
Many are asking how snow forms when it snows in the UK.
A snowflake forms when a cold water droplet freezes on to a small amount of dust or pollen in the air. This results in an ice crystal.
As the ice crystal falls to the ground, water vapor freezes onto the primary crystal, building new crystals – the six arms of the snowflake.
The atmospheric conditions that surround an entire ice crystal when it falls determine the intricate shape of one snowflake arm.
Sometimes crystals may grow arms in one way, then suddenly, or just minutes later, tiny changes in the temperature or humidity around them cause crystals to grow in another manner.
The six-sided shape of the ice crystal is maintained. However, it (and its six arms!) may break off.