Have you ever been lucky enough to witness this rare phenomenon? It appears as though children have been hard at work creating dozens of snow balls, yet leaving behind not a single footprint.
These formations, known as “snow rollers”, form when the top layer of snow picks up and is blown across a relatively flat surface. Optimal conditions for snow rollers include sticky (but not wet) snow, and astrong and steady wind. The wind must be strong enough to continue to push the snow, but not strong enough to destroy the formation. A similar shape can also occur due to gravity, when snow rolls down an open hill. On a windy day, see if you can make some “seed” snowballs and leave them out for the wind to do the rest of the work.
For more footage, check out this short video: https://www.youtube.com/