How Does Snow Form?

The first snowfall of winter is always special, but have you ever thought of the science behind how snow is formed? Find out the answer in this latest episode of Ask Dr. Universe!
Ask Dr. Universe is produced in partnership with Washington State University and Northwest Public Broadcasting. If you have a science question of your own, upload it to AskDrUniverse.wsu.edu.
Full Transcript:
- Hey, cool cats. I'm Dr. Universe, here to answer your baffling science questions, like this one. How does snow form? In a single snowball, we can find traces of water from rivers, lakes, or oceans all around the world. Water moves through our atmosphere in different forms, all the time. Clouds are made up of tiny water droplets that have turned into a gas called water vapor. It comes from evaporated water that rises from Earth's surface. Sometimes cool air up in the sky will cause water drops to hang on to pieces of dust, tiny bacteria or other things that are floating in the air. When the temperature plunges, the now-heavier drops of water will freeze into tiny ice crystals. Once snowflakes have formed up in the clouds, gravity brings them down to earth. It's a nearly 20,000 foot fall and it takes about an hour for a snowflake to make the journey from cloud to the ground. That is, if we don't catch them on our tongues first. You can submit a science question of your own at AskDrUniverse.wsu.edu.