Why lightning often strikes twice

Scientists have used the LOFAR radio telescope to study the development of lightning flashes in unprecedented detail. Their work reveals that the negative charges inside a thundercloud are not discharged all in a single flash, but are in part stored alongside the leader channel at Interruptions, inside structures which the researchers have called needles. This may cause a repeated discharge to the ground.

from Latest Science News -- ScienceDaily http://bit.ly/2IEweis