Abstract: In this study, the generalized moist potential vorticity (GMPV) anomaly and radar echoes were compared to verify the potential application of the GMPV anomaly in the development prognosis of the convective systems that are triggered by terrain and interact with sea breeze front in the Beijing-Tianjin-Hebei region. Simulations of two cases with the WRF (Weather Research and Forecasting) model were carried out for the analysis. The results showed that GMPV anomaly emerged about 0.5 to 1 hour earlier than radar echoes for the tracing of the development of convective systems triggered at the mountain leeside and around sea breeze front. The interaction between baroclinity and water vapor gradient (IBWVG) as well as diabatic heating made important contributions to the earlier appearance of GMPV anomaly. Notable perturbation of over-mountain flow and the convergence ascending of relatively moister and colder (compared to atmosphere near the land surface) sea breeze in the afternoon were the causes of the significant productions of IBWVG at mountain leesid and sea breeze front, respectively.