these photos were actually sent to me by friends of my dad pam and bill wolbert in north clarion, pennsylvania. check out their fields. they say there are thousands of these on their property alone. these are known as snow rollers. and these are happening all over the country right now, nebraska, kansas, ohio, michigan, here in pennsylvania. they almost look like snow tumbleweeds, right? or snow hay bales or snow doughnuts. >> doughnuts! >> these aren't manmade but are happening by themselves oftentimes overnight. these friends of my dad woke up in the morning and what the heck and they woke up to find a scene that looked a lot like this, in these videos. how does it happen? is it a piece of debris that gets picked up and blown? >> the national weather service basically says that there needs to be a ground layer of ice, crusty snow. then it's got to be around 30 degrees. then there's got to be new snow that falls that doesn't stick that first frozen layer. about an inch or so. then there's got to be gusts of wind that can come along and pick up that powdery snow and sort of pick up little piec