Aydin Kukavica spotted a doughnut over Montbéliard, France. As Cumulus build on thermals, they likely reached a layer of warmer air above. Like an invisible cellophane lid, this would have halted their rise, encouraging the Cumulus to curl in towards each other. It may look like Aydin’s doughnut is covered in icing, but low clouds like these are actually made of droplets.