Streamer Meets Step Leader

Okay, the quality of these images is not great. But hey, they were shot at night from a long distance, shot through our chase vehicle's window glass, shot while moving and are video frame captures...With that said, these three images show a streamer (arrow, left panel) moving upward from the ground, meeting a step leader from above as a lightning bolt (middle) and its dissipation (right). These views look east from US Highway 71, about 5.5 miles south of Early, Iowa around 8:50 PM, Saturday, April 9, 2011, and were part of a brilliant lightning display. Streamers form as objects on the surface responding to a strong electric field. The objects reach out to the cloud above by growing positive streamers. If a negatively charged step leader from above meets the streamer, an ionized conductive path is completed creating the flow of current which we know as lightning.