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In early February 2023, there was severe haze on the North China Plain (NCP) that was contemporaneous with heavy rainfall over southern China, which was known as southern rainfall-northern haze (SR-NH). Based on observational and reanalysis data, the meteorological causes of this SR-NH event are investigated in this study using correlation analysis, dynamic diagnostics and numerical experiments. The results show that the anticyclonic anomaly in the Pacific Northwest (also referred to as the northeast Asian anomalous anticyclone) is responsible for the SR-NH. On the one hand, this anticyclonic anomaly leads to persistent rainfall over southern China by causing strong ascending motion in conjunction with an anomalous cyclone over the Chinese mainland and transporting large amounts of water vapor there. On the other hand, it weakens the climatological northerly winds of the NCP through the …