Comparison of lightning detection from satellite and ground-based measurements during selected cases of convection with hail

The development of satellite-based lightning detection has enabled continuous monitoring of total lightning activity over a widespread area. However, in order to properly interpret satellite-derived lightning data, it is important to compare them with existing ground-based lightning detection networks. This study uses satellite observations from Meteosat Third Generation Lightning Imager (MTG LI) and ground-based measurements from the Low-frequency International Lightning Detection Network (LINET). A total of ten hail-producing convective cases over Croatia and neighbouring countries were selected for the period from July 2024 to July 2025.  

The main goal of this research is to compare lightning detection from MTG LI and LINET during different phases of convective storms with hail. Therefore, both spatial and temporal differences in lightning detection before, during and after hail occurrence were analysed. In addition, temporal changes in lightning properties were observed, including flash duration, area and radiance, as well as lightning type, height and current amplitude. To assess the role of storm intensity in the observed differences, the convective mode was determined for selected storms.  

The results show a good spatial agreement between the two measurement systems and a similar temporal evolution of observed lightning activity. However, the number of detected lightning flashes strongly depends on individual storm characteristics, which influence the detection efficiency of both systems. A decrease in flash area, duration and radiance was observed shortly before and during hailfall.