On May 17th, the precipitation of SCS changes abruptly, the regional averaged precipitation increases and exceeds 6 mm/day, which indicates the onset of SCS summer monsoon.

• 突变检验表明,5月17日,南海SCS4区降水发生明显的突变,与5月15日相比,SCS4区降水场形势发生明显变化,其区域平均降水突增超过6 mm/day,标志着南海夏季风降水的爆发。