Based on the data measured by PMS and GPS during a cold front process on April 24,2002, the horizontal and vertical distributions and spectrum characteristics of microphysical quantities of cloud drop and ice crystal were analyzed in this paper. And the optimum parameters of simulated functions were given out, the possible microphysical mechanism which involved were discussed. On these facts, the potential ability of enhancement rainfall was discussed and estimated.

By using the lightning data in 2000 and 2002 around Lanzhou，lightning characteristics such as daily variation，spatial density，intensity and polarity of lightning are analyzed and also compared with those in Shandong province.The results indicate that major cloud-to-ground（CG）flashes of lightning are negative.The mean intensity of positive flashes is stronger than that of negative flashes and their ratio is over average during 12：00 to 00：00.Daily variety of the CGand negative flashes is bimodalundulance，other than positive flashes unimodal.The biggest flashes frequency center locates in Weiyuan and Longxi county，and accord with the location of hail source are aand hail affecting zone. Furthermore，the spatial distribution of lightning is closely related to the topography and under lying surface and synoptic climatic background