The tracks of super typhoon “Nepartak” and “Meranti” (in 2016) are very similar. They both landed in southern Fujian, turned northward, crossed Taihu Lake Basin, and moved into the Yellow Sea. But the precipitation in Taihu Lake basin caused by the two TCs are quite different, while the former caused only scattered rainstorms, the latter generated large scale rainstorms. In this paper, the environmental conditions and structures of the two typhoons are compared and analyzed based on conventional observations, Doppler radar data, CMA-STI Best Track Dataset, and NCEP reanalysis data. The results show that: 1) The Merantis circulation structure was maintained during its landing and advance northward. With significant interactions between Meranti and the low level cold air, and strong water vapor transmission from ocean, large range heavy rainfall in Taihu Lake Basin was generated within the typhoon Inverted Trough. 2) Nepartak weakened rapidly after landing, resulted in hollowing out cyclonic circulation. The transmission of water vapor from ocean was weak and blocked. Though the superimposing of Nepartaks residual vortex and weak cold air in mid troposphere triggered scattered rainstorms, no large range of heavy rainfall presented in the Taihu Lake Basin. 3) In operational forecast, the precipitation caused by Meranti was over estimated due to a misleading stronger TC intensity forecast by numerical model. 4) Mutually validation of the forecast from empirical concept method and the ensemble model is beneficial for forecasters to get a better skill than that of the deterministic model, especially for mid-term forecast.