Abstract: A strongstorm weather occurred in the south Sichuan basin on May 7th,2015 was analyzed using the mesoscale weather charts and the radar data. The results are the followings. The convective weather arises in the regions with the cold and warm advections overlaying and the intersections of the medium to low level mains under the influence of the favorable synoptic scale system,according to the analysis on the radiosonde and ground observations. The convection storm indicates the hail echo features such as the bow echo,the vault echo and the weak echo. It is an important indicator for predicting the strong wind and the hail when the radial convergence in the middle layer occurred and the radar reflectivity rose and fall repeatedly. The sudden change of the VIL happened before and after the hail can provide the early warning of the hail. The strong wind is connected with the topography,which can promote the strong wind.