Artist Berndnaut Smilde makes clouds. These surreal, indoor installations require a fog machine and a close eye on temperature and humidity. Sure they only last for a moment, but how cool is that image?
Residents of Birmingham, Alabama woke last Friday to skies that looked more like an ocean, with a series of huge "wave" shaped crests rolling slowly across the sky. Experts have now explained the phenomenon as perfect examples of "Kelvin-Helmholtz" waves, when a fast layer moves over a slower layer and drags the top along creating a curled shape.
Roll clouds may look a lot like a wonky sideways tornado, but don't worry…they aren't dangerous. They result from downdrafts during thunderstorms where clouds break away from each other and create this cool "rolling" effect. Check out the gallery below for more shots of this cloud as it passes over Toronto.