The work describes the equipment, and its advantages, used for in-situ ground measurements of thunderstorm phenomena using measuring cars. By using all-sky high-speed cameras, radio receivers, and electric field measurements, typical lightning discharges in the central Europe region have been characterized. Measurements of ionizing radiation during storms using a gamma spectrometer were also performed. At the ground level, no ionizing radiation originating in the storm cloud was detected even though during other experiments, using the same equipment at lower altitudes corresponding to the lower part of the storm clouds, ionizing radiation was detected. We showed that radio antennas with appropriately constructed receivers and all-sky high-speed cameras are devices that can significantly contribute to the understanding of processes taking place in the storm cloud during lightning discharges. On the contrary, measurements of the vertical electric field did not provide any new information about the processes occurring in the thunderclouds.