Abstract <p>Lightning is presented as a multistable system demonstrating the ability to self-regulation by maintaining its own electrical neutrality. A nonlinear parabolic equation is obtained within the description of the lightning channel using telegraph equations with a nonlinear voltage dependence of the rate of change of the linear charge of the plasma core. The analysis of the model shows that the lightning channel is alternately developed in one of the two modes, each of which is characterized by the attenuation of the longitudinal current from one end of the lightning to the other. The transition between the modes is carried out by exciting a fast switching wave. The lightning development within each mode is accompanied by recharging of the leader system sheath and the movement of the point of the zero charge of the sheath (called the lightning reversal point) towards an increase in the longitudinal current. The movement of the reversal point is due to a change in the average potential of the discharge tree during the recharging of the sheath and explains the observed dynamics of lightning transients.</p>