Abstract: A thunderstorm weather that seriously impacted air traffic on 13 September 2013 in Shanghai is studied. Using satellite imagery,Doppler radar and conventional observations, synoptic and mesoscale weather conditions for this event are analyzed, with focus on the evolution of different weather systems and their interactions. Results are as follows. (1) This event occurred under the condition of a deformation field. Several factors are favorable to the development of the storm, such as strong unstable stratification, sufficient water vapor in the low level and strong large-scale the convergence and upward motion induced by high- and low-level jet interaction. (2) Under such favorable conditions,the surface wind convergence triggered the unstable energy to be released, and triggered the initial convection in northern Shanghai. (3)Based on meso-analysis, it is indicated that there are three γ or β-mesoscale convictive systems during this heavy precipitation event. The convective cells are initiated and propagated along the boundary layer convergence line. Therefore, boundary layer convergence line analyses is very important for early warning and prediction of the convective systems.