Abstract:This paper analyzes the characteristics of cloud-to-ground (CG) lightning in rainstorm and hail event that caused by a cold vortex, by using data collected in lightning detection network, Doppler radar and intensive automatic weather stations. The results show that there are dense areas of CG lightning in the process of rainstorm and hail, and the proportion of positive CG lightning in hail is higher than in rainstorm; the negative CG lightning predominates in rainstorm, which is mostly located at the core area of rainstorm and mainly in the radar echo area of above 45 dBz, and its lasting time is equivalent to the duration of rainstorm. The negative CG lightning frequency and its growth rate reach the peak 30-70 min ahead of the area of strong radar echo, and it has a certain prediction significance for short term rainstorm forecasting and early warning. In the hail process, negative CG lightning is concentrated in front of hail cloud, and the positive CG lightning is located at the core area of hail cloud, which is consistent with hail area, and the regions of positive and negative CG lightning begin to separate. The total number of CG lightning and the area of strong radar echo have a similar changing trend. Positive CG lightning occurs about 30 min ahead of hail. The total CG lightning and positive CG lightning frequencies are increasing considerably before hail. Hail occurs during the period that the total CG lightning, positive CG lightning and the area of strong radar echo reach the peak and decrease rapidly. The total CG lightning number decreases, but the positive CG lightning increases in the dissipating and weakening phase of hail cloud.