Spotted floating above Las Olas Beach in Maldonado, Uruguay, this amazing roll cloud is basically caused by “a downdraft from an advancing storm front can cause moist warm air to rise, cool below its dew point.” Video after the break.

When this happens uniformly along an extended front, a roll cloud may form. Roll clouds may actually have air circulating along the long horizontal axis of the cloud. Despite the circling air a roll cloud is not thought to be able to morph into a tornado.

[via Dailymail]