The location of lightning flashes at ranges less than 100 km

The positions of ground flashes were located to within a few kilometres from bearings given by a network of all-sky cameras. Comparisons between these bearings and those from electrical (crossed-loop) direction-finders showed that 60 per cent were within ± 5° of one another and 80 per cent were within ±10°. Ground flashes from a particular storm were often found to have occurred at random within an area of about 10 km2 during intervals of approximately 10 min. On occasions, consecutive flashes were displaced systematically relative to each other. Flashes frequently occurred close to the leading edge of precipitation.