Roll clouds

A roll cloud looks like a rolling pin blanketed in cotton, hanging in the sky under higher clouds, appearing to rotate in place, often stretching from horizon to horizon. Yes, mind-blowing. This rare type of arcus cloud forms when a solitary wave pattern called a soliton sets up in the atmosphere and sustains itself in a roll form, usually near a seacoast or a severe thunderstorm. Also called morning glory clouds, coastal roll clouds sometimes form one after another; sightings of as many as 10 parallel rollers have been reported. #COOL!