Vaisala Lightning Explorer

Vaisala Lightning Explorer, is a free online lightning map that is accessed by a web browser, and it displays thunderstorm movement and lightning activity recorded during a 30 minute period, on a map of continental U.S.A. Lightning activity data is refreshed every half an hour.

Lightning data source is the U.S. National Lightning Detection Network®.  Lightning data of the U.S.A. is only available,  as the NLDN only covers continental U.S.A.