system seemed to have smaller amounts of static discharges then we often associate with storm clouds of this nature. These discharges we call lightening are caused by the transfer of electromagnetic charge from the surface to the atmosphere as the rising water vapour zooms upward. The actual lightening event actual occurs upward from the earth rather then downward as it appears to us on the surface. The static imbalance builds up until the potential exceeds the resistence of the air which normally an insulator rather then a conductor of electricity. If you are ever in an open place and notice your hair or fibers beginning to rise upward with a cloud over head, get under cover immediately as lightening is imminent and the discharge can be deadly.
The image above is the same cloud seen on the previous page, only now the bottom edge of it has come over us. The undulating appearance of the bottom of a cloud of this type indicates the continuing and strong updraft of rising moist air up into the towering cloud.