In the morning sky, long rows of clouds stretch from one end of the horizon to the other. They look much like enormous tubes—smooth in some places, undulating in others. This elongated cloud formation moves along with the wind. Seen from a distance, it can seem as though some giant roller is turning across the sky. This is no science-fiction scene. Such clouds are created in nature itself. Meteorologists know them as "roll clouds." Their most famous example is the "Morning Glory," which is seen...
