Temperature
According to the National Snow and Ice Data Center, "Snow forms when the atmospheric temperature is at or below freezing." If the ground temperature is also 32 degrees or below, the snow falls to the ground without melting.
Moisture
Snow flakes are oddly shaped ice crystals. For snow flakes to form, there must be water vapor in the air, also known as clouds.
Falling Snow
As the ice crystals grow, they increase in mass and eventually fall. The more moisture in a storm system, the quicker flakes fall.
Geography
snow mountain landscape image by A74.FR Ben Fontaine from
Fotolia.com
According to the United States Search and Rescue Task Force, geography has a profound effect on weather. Mountains and large bodies of water create highly variable weather conditions, causing snow in one place and blue skies a few miles away.
Snow Above Freezing
Snow can fall when ground temperatures are slightly above freezing. When the snowflakes reach warmer temperatures, they begin to melt and evaporate, creating cold pockets of air around each flake.
Article Written By Ryan Tuck
Born in Colorado, Ryan Tuck grew up with the outdoors in his backyard. After attending Whitworth University in Washington state, he returned to his hometown and built a popular hiking and biking trail guide. Today, Tuck helps others enjoy the outdoors by writing for Trails.com.