In Gallatin, some storm watchers captured wild-looking shelf clouds moving overhead. Lacey Baker shared photos and video of the clouds on Tuesday afternoon. Shelf clouds form at the leading edge ...

Shelf clouds are the low, horizontal formations that often precede a thunderstorm, hanging ominously like a vast shelf in the sky. These clouds form along the edge of a cold front and indicate ...

A timelapse video shows a stunning shelf cloud moving across the sky in southern Brazil. The dramatic footage was filmed in Caxias do Sul. About ten million people face water rationing as severe ...

While these wave clouds typically form in clear conditions, as Wilkie saw in Calgary, they can also form ahead of thunderstorm shelf clouds of severe thunderstorms in rare instances, as shown in ...