Abstract:During the summer of 2025, the rainfall belt in the central and eastern regions of China was mainly situated in the northern part. Precipitation across north-central North China, central and southern Inner Mongolia, and northern Shaanxi exceeded the climatological mean amount by 50% to 200%, result-ing in severe flooding and related disasters. The rainy season in eastern China exhibited a delayed onset, followed by an early withdrawal. In North China, the onset timing, duration, and accumulated precipita-tion of the rainy season all broke historical records. The excessive precipitation was primarily driven by the pronounced northward displacement of western Pacific subtropical high (WPSH) and the more strengthened East Asian summer monsoon. In addition, intraseasonal variations in the East Asian atmospheric circulation substantially modulated the spatial pattern of monthly precipitation anomalies. Among these influences, anomalous Madden-Julian oscillation (MJO) activity served as a key regulator of intraseasonal circulation variability. In June, frequent Northeast cold vortex activity, combined with a stronger and northward-migrating WPSH, triggered an earlier onset and prolonged duration of the Meiyu season in the Yangtze River and Huaihe River (Jianghuai) Basin, leading to significantly above-normal precipitation in the Meiyu region. In July, persistent MJO convection from the Maritime Continent to the western Pacific subtropical region promoted anomalous typhoon genesis and further northward shift of the WPSH over the northwestern Pacific. As a result, the main rainfall belt was located in the northern part of North China to Hetao Region, the southern part of South China and the southeast coast, resulting in severe typhoon rain and floods. In August, the MJO activity was enhanced in the African-Indian Ocean Region, favoring the even stronger, westward-extending and southward-moving WPSH, further increasing the rainfall amount in the areas north of the Yangtze River Basin.