Roll Cloud Uruguay

Roll Cloud

Photo Daniela Eberl.... Las Olas beach

This type of cloud form ahead of a cold front and can stretch for miles.
They are most common when an advancing storm front causes moist air to rise, then cool to the point where it becomes a cloud known as the dew point. These do not form into tornadoes

First New Cloud Specie Since 1951

http://news.nationalgeographic.com/news/2009/06/photogalleries/new-cloud-pictures/

http://www.meteorologynews.com/2009/06/06/new-cloud-type-discovered-undulus-asperatus/

Gavin Pretor -Pinney, Put the name of Undulatus/Undulus Asperatus forward as a new cloud specie in 2009 it now has official recognition as such