7 May 2014 Red River Supercell

VortexChasers.net provide this time-lapse of a nice supercell that traversed the Red River (of the south).

27 May 2012 Kansas Shelf Cloud

This lapse features the tail-end of a mostly disorganized, messy line of storms in north-central Kansas. A pool of cold outflow induces a roll-shelf cloud hybrid. I.e., it starts out as a roll cloud detached from the parent storm, but then transitions to a shelf as the outflow generates new convection. Though difficult to see in the lapse, a shear funnel forms within the shelf near the telephone pole at 0.07s.

Colorado Roll Cloud

This short sequence by John Huntington illustrates a neat roll cloud bear Brush, CO on 8 August 2010. Roll clouds are a type of arcus cloud, and are differentiated from a shelf cloud because a roll cloud is detached from the base of the thunderstorm.