Nature Notebook – Snowflake Crystals

This winter is providing us with plenty of snow and a busy cross-country ski and snowshoe season at the Nature Center. Some snow makes for better skiing or snowshoeing conditions than others and many factors such as atmospheric conditions and ground temperature can affect the type of snow that falls.

Snow forms during a storm when temperatures are below 32 degrees and a nucleus of dust or salt attracts water molecules from cloud droplets. They accumulate and form ice crystals that become large enough to fall to the ground, often changing shape along the way.

When observing the snowflakes close on a dark glove or with a magnifying glass, different crystal shapes can be noticed. The type of crystals formed in a snowstorm determines the snow cover that people and wild animals and plants deal with.

Some common crystal observed are stellar or dendrite star-shaped crystals, column crystals and hexagonal crystals. Stellar crystals form when there is plenty of moisture and not too cold temperatures, often creating a slow, peaceful snowfall and good ski conditions.