A lesson can be learned from the El Reno event by any chaser but you look at this video and you wonder how quickly things can change in a dangerously volatile environment! These guys were counting seconds I can assure you before they could have been in the fields. Apparently Tim Samaras was on the same route behind this. Why people were not taking notice of the wide mesocyclone I do not know! Look to the right of the main focus of the tornado hanging back and this was the sign of the killer about to happen unfortunately! David Croan and I both saw it and watched it!
Having said that, this is the largest wall cloud I have ever seen - check this as you watch them go down the road!