Abstract:A local heavy rainstorm in northeast and southern Hebei on July 18, 20 07 is analyzed by using conventional observation data, hourly data of automated weather station, TBB data and NCEP 6 hour re analysis data. Conclusions are dra w n that although in the same synoptic system, the rainstorm formation mechanism i s different in different regions. It is revealed that the upper level and low le vel jet streams as well as the interaction between the positive feedback of the jets and rainstorm are the main reasons causing the north east rainstorm in the m orning. The vapor is transported by low level jet stream. There are round li ke meso α convective cloud clusters with TBB less than -70℃ in the image of th e FY-2C. The severe event in southern Hebei in the afternoon occurred under the f av orable conditions of the high temperature, high energy and unstable stratifica tion when instable energy was triggered and released by the co ld front and the low pressure before the front. In the corresponding images there are quasi trans me ridian convective cloud clusters with minimum TBB less than -80℃. The streams a nd surface humid static energy calculated from automatic weather stations data h ave significant indication to prediction of this sort of summer strong convectio n weather.