Abstract: This study has exploited daily reanalysis data and high-resolution precipitation data for the period of 1979 to 2007 to investigate the northward jump of the Meiyu rainbelt and its possible physical mechanisms. The northward jump dates of the Meiyu rainbelt are determined. Results show that the northward jump dates of the Meiyu rainbelt vary greatly from year to year. Composite results of the Meiyu northward jump process revealed in this study are consistent with results of previous studies. Water vapor transport and vertical motions in the middle troposphere play a crucial role in determining the spatial distribution of Meiyu rainbelt. Diagnostic results of the Omega equation indicate that anomalous circulations in the upper troposphere induce descending motion anomalies over the Yangtze-Huaihe River basin, which inhibit the northward jump of the Meiyu rainbelt. Meanwhile, diagnostic results of a vorticity equation suggest that the anomalous diabatic cooling associated with the anomalous descending motions over the Yangtze-Huaihe River basin produces anomalous anticyclonic vorticity tendency over East China in the lower troposphere, which is favorable for the westward shift of the subtropical high and the northward jump of the Meiyu rainbelt. The above results show clearly that the sudden northward jump of the Meiyu rainbelt is attributed to anomalous ascending motions over the Yangtze-Huaihe River basin, which are associated with circulation anomalies in the upper troposphere (primarily driven by zonal vorticity advection).