Lightning is complex.
The air at the lightning bolt is heated to about 30,000 degrees, three times the temperature at the surface of the sun. The current carried in a lightning flash can be as high as 10,000 to 20,000 amps. The start of lightning occurs with an intense electric field. This field accelerates the few free ions in the atmosphere to very high velocities. These ions smash into molecules and atoms of oxygen and nitrogen and break them apart, creating even more ions and electrons.