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Using the synchronous data of the lightning monitoring and warning network， Doppler radar， and regional AWS precipitation from a severe storm occurred in Qinhuangdao on 6 July 2009， a detailed analysis is carried out. The results show that the lightning process was dominated by negative ground flashes， with the maximum of lightning frequency being 712 times per hour； the lightning discharge trajectory was northwestsoutheast oriented， moving from north to south， with the hourly rainfall being more than 100 mm per hour when the maximum lightning frequency occurred； there was simultaneous phenomenon of lightning frequency and precipitation intensity. The disasterinducing lightning and heavy rain event was caused by two βscale convective cloud clusters at the different phases， whose structures and physical characteristics of the radar echoes were obviously different. Between 06:00 and 07:00， the radar echo intensity was 45 to 50 dBz， with the main echo having a compact structure and the cloud top height being more than 10.5 km； the radial velocity chart had obvious adversewind areas and a strong lowlevel convergence zone， and there was strong vortex ascending motion， with the liquid water content being 20 to 25 kg/m2. Between 14:00 and 15:00， the radar echo intensity was 50 to 55 dBz， and the main echo was composed of multiple convective cells， with a relatively loose structure； the cloud top height was greater than 12.8 km， and the radial velocity had obvious wind shear; the liquid water content in the afternoon was slightly more than that in the morning， being 25 to 30 kg/m2； the lightning density area corresponded well with strong echoes； the movement of dense lightning areas reflected the trends of strong convective cell movement； the radial velocity convergence zone corresponded with the frequent lightning activities； the distribution of radar echo tops was the same as the distribution of lightning activities.