Lightning originates around 15,000 to 25,000 feet above the ground when raindrops are carried upward until some of them convert to ice. For reasons that are not widely agreed upon, a cloud-to-ground lightning flash originates in this mixed water and ice region.
The charge then moves downward in 50-yard sections called step leaders. It keeps moving toward the ground in these steps and produces a channel along which charge is deposited. Eventually, it encounters something on the ground that is a good connection. The circuit is complete at that time, and the charge is lowered from cloud to ground.
The return stroke is a flow of charge (current) which produces a luminosity much brighter than the part that came down. This entire event usually takes less than half a second.
Just to clarify what Galvan said about Lightning, the actual visible
lightning stroke travels from Ground to Cloud. There is video
evidence of this and I now call Streak Lightning, Ground to Cloud.
As for the Tornado question, people have lived through direct
tornado contact and have told us what they saw inside the tornado.
According to reports, you can see straight up the funnel to the sky.
There were 2 "mini-tornados" inside the funnel with constant lightning.
The Film "Twister" takes this question on, at the end of the film.
2 Mini-Twisters and constant lightning and able to see the sky.
So, what is inside a tornado? Mini-Tornados and constant lightning.
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