Dramatic roll clouds across Florida
Video: Roll clouds across southern Florida, taken 31st March 2016 Source: YouTube
Roll clouds are low, horizontal and tube shaped, and are a type of arcus cloud. Shelf clouds are another type of arcus cloud, however roll clouds are different due to the fact that they 'stand alone' and are detached from other clouds. One of the main causes that leads to the development of roll clouds are associated with sea breezes. However, roll clouds can also be found away from coastal areas, at the leading edge of thunderstorms, with downdrafts causing the development of the feature, as storm-cooled air moves outward and forms a cloud barrier with the surrounding warmer air.