Three local heavy rain events have similar location of rainfall, which occurred in Xiangshan, Shijingshan and Mentougou area in the west of Beijing fr om the end of June to early August of 2006. Product of Doppler radar exploration is used to do fine analysis and research. The result shows that development and evolvement of radar echoes in these three events are different thoughsimilar l ocation of rainfall. The influence of vertical wind profile of westerly in bound ary layer on location of torrential rain is consistent under the action of topog raphy. The south-east wind from the plain in surface layer is almost vertical to the mountain lasting about 6 hours and strengthens temperature and humidity con dition in surface layer in the front of mountain. Convergence and lifting in sur face layer in the front of mountain form under obstruction of mountain in the we st of Beijing. Westerly winds in boundary layer around top of the mountain provi de beneficial factor for divergence in boundary layer by lifting in atmospheric surface layer. Studies also indicate that development and evolution of mesosca l e and microscale systems such as thunderstorm cell around location of rainfall and mesocyclone are key factors that decide the location of torrential rain.