Abstract:In the springtime (March-May, MAM) of 2024, the average precipitation in China was 163 mm, ranking the sixth most precipitation since 1961. During April-May, eastern region of China experienced both severe droughts and floods. South China and most of Jiangnan Region experienced significantly above-average rainfall, with most parts of South China receiving rainfall more than normal by over 50%. Thus, multiple times of torrential rain events led to flood disasters in some areas. Conversely, northern Jianghuai and Huanghuai regions had notably below-average precipitation, which caused the rapid development of drought in later spring. The phenomenon of “floods in South China and droughts in Huanghuai Region” was mainly influenced by atmospheric circulation anomalies in East Asia and their intraseasonal variation. The abnormally strong and southward western North Pacific subtropical high (WPSH) and extremely strong anomalous western North Pacific anticyclone (WNPAC) in April provided favorable conditions for moisture transport, leading to frequent occurrence of intense precipitation events in southern China. The drought over Huanghuai Region was primarily dominated by persistent strong high pressure system near the Korean Peninsula-Japan Sea (Bonin high) in April-May, along with a southward shift of the WPSH. Additionally, the attenuation of El Ni〖AKn~D〗o and abnormally warm sea surface temperature in the tropical Indian Ocean contributed to the activation of abnormally strong WNPAC, which built the important oceanic external forcing background for heavy rainfall in southern China.