Using the ECMWF-HRES model as a benchmark, this study conducts a comparative verification and evaluation of 12-84 h operational forecasts produced by the CMA-GFS-V4.0 and CMA-GFS-V4.2 models over the Changjiang-Huaihe region during the 2024-2025 Meiyu periods. The results are as follows. (1) The depiction of the 500-hPa large-scale circulation during the 2024 Meiyu period by CMA-GFS-V4.2 is generally consistent with that of CMA-GFS-V4.0, with improved simulation of the East Asian jet position; however, the 850-hPa low-level jet forecasts still exhibit overestimated intensity and excessively large spatial extent. (2) In terms of graded precipitation forecasts and the spatial distribution of precipitation, CMA-GFS-V4.2 shows notable improvements over CMA-GFS-V4.0. The verification results for the 12-84 h forecasts indicate that although the false alarm rates increase for moderate and heavy precipitation categories, the forecast performance for light rain, rainstorms and severe rainstorms is significantly enhanced relative to CMA-GFS-V4.0, with higher threat scores (TS), Bias values closer to 1, and overall improvements in statistical metrics including correlation coefficient, standard deviation and centered root mean square error (CRMSE). Compared with ECMWF-HRES, CMA-GFS-V4.2 demonstrates superior capability in predicting extreme precipitation events of severe rainstorm intensity or above over the entire verification period. During the operational forecasts of the 2025 Meiyu period, CMA-GFS-V4.2 exhibits stable performance and overall outperforms ECMWF-HRES in the forecasts of rainstorms and more intense precipitation. (3) CMA-GFS-V4.2 is able to better depict the primary heavy precipitation centers, effectively alleviating the spurious precipitation bands and false alarms over the coastal land-sea transition zones present in the previous version; however, its performance in forecasting large-scale precipitation remains relatively weak and requires further optimization.