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Based on the lightning monitoring data from the Chinese ADTD (Advanced TOA and Direction system) lightning locator network and the NCEP (National Centers for Environmental Prediction) reanalysis data from 2010 to 2019, this analysis combines weather verification indicators such as TS scores and forecast deviations to provide the physical characteristics of environmental conditions related to lightning in different regions in China. The characteristics of lightning activity show a pattern of more lightning in the south and less in the north, with the highest lightning density in South China, followed by the eastern parts of Jiangnan and the eastern regions of Southwest China. Regarding monthly frequency variations, except for June, which sees a higher occurrence of lightning in South China, August records the highest lightning frequency nationwide and in most regions. In terms of diurnal variation, cloud-to-ground (CG) lightning activity is most concentrated in the afternoon, with the daily peak at 16:00. The analysis of environmental conditions indicates that thermal environmental characteristics significantly indicate lightning occurrence, and thermal-related physical quantities have the best indicative significance for lightning occurrence, followed by water vapour physical quantities. The indicative role of dynamic-related characteristic quantities is not significant. Among them, the K index is the best index nationwide, with an optimal threshold of 37 ℃. For different regions, there are significant differences in the conditions of low-level water vapour, mid-level water vapour saturation, cold air intensity, and temperature difference between high and low levels. Comprehensive statistics show that regions with better low-level water vapour conditions are more sensitive to the K index and have relatively higher thresholds, such as northern China, the Yangtze River Basin, and southern China. For mid to high latitude regions, atmospheric instability is more sensitive to lightning occurrence, so indices such as BLI and LI perform better. The water vapour condition is a necessary factor for lightning occurrence, but its indicative significance for lightning cannot be used alone as a basis for lightning prediction. It should be determined by combining atmospheric circulation and other environmental field characteristics. Dynamic effects are deemed a necessary condition for the development of severe convective weather, although their ranking in the verification of dynamic indicators is relatively lower, failing to accurately reflect their importance for lightning occurrence. The lightning forecasting in China mainly relies on the determination of the location of lightning occurrence. It is necessary to combine the atmospheric circulation situation and environmental water vapour, dynamics, and thermal conditions to determine the area and possibility of thunderstorm occurrence, and then measure the accuracy of the forecast through weather verification indicators. These findings provide an objective reference for understanding and forecasting lightning activity in different regions in China.