via.kdvr.com
Rare wave-shaped clouds roll over Virginia
ROANOKE, Va. -- A rare formation of clouds wowed onlookers at Virginia's Smith Mountain Lake on Tuesday. The photo shared on social media captured clouds that look like ocean waves in the sky. These clouds rarely form on windy and unstable days, but when conditions are just right, the natural phenomenon, known as Kelvin-Helmholtz Waves, occurs.