A snowy landscape seems magical, but snowflakes are complex structures that form slowly in the clouds before making their way to the ground. Learn a little about the science behind snowflakes. It will make you appreciate that powdery panorama even more.
A crystal in the clouds
A snowflake starts high in the Earth’s atmosphere when a cold drop of water meets a particle of dust or pollen. Water vapor surrounds the particle and forms an ice crystal, the building block from which the snowflake will form.
Falling into place
The newly formed ice crystal is heavier than the surrounding air, so it begins to fall. More water vapor freezes onto the crystal structure as it descends through the humid air.
Six sides to every snowflake
Every snowflake has a hexagonal or six-sided structure? Why? Because the water molecules that form the ice crystal naturally arrange themselves in a hexagonal pattern, and that’s the form the snowflake takes.
One of a kind
Every snowflake may be six-sided, but they’re all unique. Snowflake shapes range from simple, flat structures to intricate patterns with branches or arms. The temperature and humidity level in which the snowflake forms determines its shape, and slight changes in weather conditions can give it a makeover. As a snowflake swirls around, its pattern can vary many times.
As it exits the clouds, what are a snowflake’s chances of reaching the ground as a snowflake? It depends on the air temperature as it falls. If the snowflake passes through a thin layer of warmer air, it could partially melt and refreeze, forming a tiny ice pellet called sleet. A thicker layer of warm air could cause the snowflake to melt completely, hitting the ground as freezing rain.