In his Thunderblog on 2017-06-13, Hall described a tornado as an electric current from the cloud to the ground.

If the ionization rate exceeds the rate of recombination, the plasma will build a streamer, a tendril of plasma from cloud to earth, pushing a plasma generating ionization region ahead of it, and drawing behind it a cloud of cold plasma. When this plasma hits ground, a cathode spot is produced, and the electromagnetic field redistributes along the plasma channel, focusing it.

 

The cathode spot on the ground draws a positive charge to it, dragging neutrals, again by electrokinesis, and creating the in-flowing winds that generate a ground vortex. This is the moment of a tornado touchdown, as charged air and dust flow in and spiral upwards around the invisible plasma tendril.

So he has the current going into the ground. But then he has air being drug into the cathode spot, because of the electric force on charged particles in the air. The problem is that the solid Earth is a much better conductor than the air, and if not adequately insulated from the discharge path, will handle as much current as the cloud has. By comparison, the air is a fair resistor, and thus wouldn't be involved. Indeed, an "ionic breeze" is easy to demonstrate with 6 kV applied to a needle grid (i.e., enough to ionize air molecules). But not in the presence of a solid conductor, which handles the current before the surrounding air gets a chance to look at it.

 

If Hall is going to stick to the cloud-to-ground current model, the next really tough question is, "Why isn't there evidence of such a current on the ground?" I'm using 10 amps as the minimum current to sustain an EF1 tornado. Most researchers go with a lot more. Anything with more resistance than a 14-gauge solid core copper wire is going to burn up if 10 amps tries to flow through it. And yet selective charring or vaporization has never been observed in the damage path of a tornado. And we should remember that such debris is sorted by hand, as people try to recover their valuables. If a 10+ amp electric current was present in every tornado, the evidence would be everywhere, and we would know all about it.

 

And the next problem with a cloud-to-ground current is that it would latch tightly onto good conductors, such as railroad tracks, rivers, etc., and not let go until it found the next best conductor nearer to the source of the electrons. But tornadoes slide right over railroad tracks and rivers, as if they weren't there. The damage paths of over 1,000 tornadoes are cataloged every year in the U.S., going back 50 years with good records, and no one has found a correlation between tornado path & terrain.

 

Clearly the ground is not involved in the current.