A snow roller, according to wikipedia, is a ‘rare meteorological phenomenon in which large snowballs are formed naturally as chunks of snow are blown along the ground by wind, picking up material along the way, in much the same way that the large snowballs used in snowmen are made.’ Snow rollers are made with a combination of specific conditions. This includes a relatively thin surface layer of wet, loose snow and a lower surface layer like ice underneath.
Wind must be strong enough to move it but not too much in which the snow roller will fall apart.
These snow rollers were seen north of Castor, Ab., at Marion Steinwand’s farm on Fri. Jan. 25. One snow roller was measured to be between five and half inches to six inches in height.