Nature Made Snow Balls

Looked out the window one morning this past winter.  A fresh snow had fallen and the yard had several sets of tracks.  Hmm.  What kind of a critter would make tracks like this?

Oddly spaced, uneven and no uniformity of size.  

So there is the culprit!  

 First time I'd seen "snow rollers".  Snow falls at a temperature warm enough to make a good snow ball and the wind gets a small ball of snow rolling and away it goes, getting ever larger until it becomes large and heavy enough it stops. 

 It made the news in Central Illinois an this unusual phenomenon occurred throughout the region.