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Evolution of thunderstorm electrification before first lightning strike

Cloud-to-ground lightning flashes are among the most dangerous natural phenomena in the world. To reduce lightning hazards, it is needed to investigate the evolution of thunderstorm electrification before the first lightning strike by electric field measurement. Electric field measurement at ground level is used as a basis for lightning hazard warnings. Also, weather satellites can provide valuable information about the location of convective cells that can potentially become thunderstorms. In this study, the relationship between electric field changes at ground level and thunderstorms before the first lightning stroke to the ground was investigated. It was found that the first cloud-to-ground lightning flashes were always preceded by an atmospheric electrostatic field change at ground level by several hours.