The two different wind elements combined lifting dust into the air thousands of feet. The base of the cloud is about 6,000 feet above the ground. This extreme wide angle image shows the two circulations well defined under the rotating cloud. Dust from the south vortex is well over a thousand feet into the atmosphere and rising. During the early development stage of these two circulations dust may be seen rising to cloud base as multiple whirls spin in the field.
Dust is obvious entering the cloud base.
Most of these shots are from a wide prospective. I was under a mile from the event. I'll estimate the base of the south circulation at 100 meters wide and the north one about 40 meters wide. Wind speed was probably near 50-60 mph. First, it's interesting that small circulations like this carry dirt to the cloud base over a mile above the field.