Watch a weird Roll Cloud float over Chicago
Amy King was on the lakefront in Chicago to record this video of a cloud rolling in.
Meteorologist Cheryl Scott explains:
What is a Roll Cloud and how does it form? It’s a low, horizontal, tube-shaped cloud. It is formed by winds changing speed/direction when the air temperature reverses its state (resulting in warm air on top of cool air). The shear in the atmosphere sets up a rolling motion, think [of a] rolling pin used in a baking.