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Based on the intensive automatic weather station and radar wind profiler data with high temporal and spatial resolution， the mesoscale observational characteristics of three shortduration rainstorm processes in Xingtai city are analyzed. The shortduration rainstorm was produced under the favorable largescale circulation background. The lower layer shear system， strong vertical wind shear between middle and low levels， surface low pressure and inverse trough were the favorable conditions for convergence and ascending motion. The warm wet air flow from southwest interacted with the cold air from the westerly winds and northeast backflow. The surface mesoscale shear was the trigger system， whose position was consistent with the intensive precipitation area. The intensive precipitation corresponded to the beginning， duration， and strength of east winds in the boundary layer. The surface ascending eastwinds were forced by the convergences resulted from the topographic forcing， and so the mesoscale convergence system was strengthened. The urban atmospheric thermal forcing and topographic effect triggered jointly the urban shortduration rainstorms.