28-03-2025
Magnificent roll clouds caught on webcam over Florida's east coast
Weather enthusiast Adrian Linares was watching his webcam in Lake Worth, Florida, on Tuesday morning when something unusual happened: Three roll clouds moved over his house.
Roll clouds mark a sharp temperature contrast where warm air moves up over shallow cold air, continually reforming water vapor in the same place, like a lenticular cloud. Since temperature boundaries move while the moisture boundaries of a lenticular cloud do not, the roll cloud can move along the atmosphere as the boundary moves downstream.
A roll cloud over the fleet onboard MAPFRE during the start of Leg 7 from Newport, Rhode Island, to Lisbon on May 17, 2015 in Newport, Rhode Island. (Photo by Ainhoa Sanchez / Volvo Ocean Race via Getty Images)
Roll clouds often come in groups of two or three. Catch the rare clouds at the so-called golden hour, and the results can be stunning, as storm chaser Bill Hark found out in 2018 in Richmond, Virginia.
A roll cloud, lit by the sunrise in Richmond, Virginia, on Feb. 5, 2018. (Bill Hark)
Roll clouds are officially known as Volutus clouds and form in a fashion similar to the shelf cloud that precedes a thunderstorm, but is not attached to a thunderstorm, and in fact, most often occurs in fair weather.
One of the most common places to see a roll cloud is at the beach. In the Gulf of Carpentaria region of northeastern Australia, where roll clouds occur regularly, they are known as a morning glory. Roll clouds can also give shape to a gravity wave in the atmosphere causing rising and falling air, known scientifically as an undular bore.
