The last storm shot I would take while chasing in Oklahoma, during 2010. This cloud had produced three tornados earlier in the day, and I was waiting for it to pass the township of Guymon before trying to get to my hotel. It was still spewing 1-1/2" hail and I didn’t want to get caught in that. The streak you see along the horizon is a car approaching me down hwy 412 during the time I had my shutter open.
I previously did post a shot that looked a lot like this one, but I think I got a better exposure here, which shows off more detail of the shape of the cloud structure.