March 2, 2012 Satellite Loop (NASA Earth Observatory)
The image you see here is the surface analysis of March 2, 2012 at 4:00pm. You can see very clearly the warm sector (the area of mild air) between the cold and the warm front. This warm raising air is one of the many factors acting as fuel which allowing the tornadoes to spin up within their supercells.
The image you see here is a still from the satellite loop video at the top of the page. Just like in the first video, you can see the funnel shape the cloud cover has taken on. This is the exit region of the jet stream, and is where the supercells are located. You can very clearly a few individual supercells at the narrow region of the funnel (cloud patches)