中文摘要：

利用雷电定位资料、多普勒雷达资料和FY-2E卫星红外资料对发生在滇西南的一次MCS过程进行了分析,结果表明：西移的＂凡亚比＂热带低压和低空东风急流为MCS的发展提供了较好的暖湿条件;整个MCS过程负地闪占主导地位,发展阶段负地闪频数波动增加.成熟阶段以负地闪占绝对优势,负地闪频数〉150次/10 min,正地闪开始出现并缓慢增加,消亡阶段,负地闪明显减弱,正地闪频数剧增;MCS的3次飑线过程较好地对应着负地闪频数的3个峰期,负地闪密集出现在MCS成熟阶段云顶亮温≤-60℃的区域和前部云顶亮温梯度大值区,正地闪出现在密集负地闪后部和云团中部;在多普勒天气雷达上,MCS表现为由多个不同尺度对流单体组成、具有不均匀结构的中尺度带状回波,上升气流的倾斜特征使负地闪密集出现在强回波区左后侧强度≥40 dBz、回波顶高≥10 km的区域,与最大回波区位置并不重合,回波顶高与地闪发生位置有较好的正相关;负地闪频数达到最大峰值后正地闪开始出现;飑线减弱阶段正地闪频数增加且分散在强回波后部边缘或后部弱对流回波和层状云回波上;〉12 m/s的大风区不利于产生强地闪活动.

英文摘要：

Using the lighting data, Dopplar radar data and FY -2E satellite infrared data, a Mesoscale Convective System process in south - west of Yunnan is analyzed, The results show that the advantageous conditions of warm atmosphere and wet atmosphere are supplied by tropical depression moving west and east jet on the low layer. The negative cloud - to - ground （ - CG） lightning is predominant to positive cloud - to - ground （ ＋ CG） lightning during the whole lifetime of MCS and - CG flash rate increase slowly with the fluctuations at the first developing stage. -CG lighting occupies absolute predominance and flash rates is above 150 times every 10 minutes as the same time as the ＋ CG lighting increasing slowly at the ripeness stage, - CG lighting declines obviously and the ＋ CG lighting insreaes rapidly at dissipating stage; there are three peak stages of -CG flash rate corresponding to three squall lines nicely, -CG lighting mainly clusters in the region that cloud top temperature is under -60 ℃ and the fore cloud top temperature gradient is largest at the ripeness stage, but ＋ CG lighting disperses in the rearward of dense - CG lighting and the cloud center during the process of MCS ;The mesoscale zonal echo with asymmetric configuration figures formed by many different scales of convection cells on Doppler weather radar; -CG lighting mainly clusters in the left rear region echo with high reflectivity （ ≥40 dBz） and high Echo Top （ ≥ 10 km） because of the sideling feacture of updraft inside MCS,that is not coincided to the Strongest echo region, the reion of echo top is positive correlate to that of - CG lighting; The ＋ CG lighting begins to grow after the peak stage of - CG lighting,The ＋ CG flash rate increases and disperses in the rearward of intense echo region or on the weak convective echo or sheet echo at dissipating stage, CG lighting emerge less in the blustery region（ 〉 12 m/s） ;the character of echo intensity ≥48 dBz at -10 ℃ altitude layer,echo top≥15 km can b