This image represents lightning strikes detected across North America by The Weather Network Lightning Detection Network during the half hour period prior to the time displayed. Each lightning bolt symbol corresponds to an individual strike. Both cloud-to-ground and cloud-to-cloud strikes are plotted. Lightning bolt symbols with a dark outline indicate areas of more frequent lightning activity.
Lightning is a discharge of electricity that occurs in mature thunderstorms. It always precedes thunder because lightning causes thunder. The lightning stroke momentarily heats the air it passes through to an incredibly high temperature. It can heat the air to 30-thousand degrees Celsius. The rapidly expanding air produces a sound called thunder. Along with the lightning and thunder, severe thunderstorms produce destructive hail, downbursts, and even tornadoes.