Why does the East China Sea have rainy summers?

The rainy summers in the East China Sea are primarily driven by the regional monsoon wind system, which results from the differential heating of land and water.12

During the summer, the Asian landmass becomes significantly warmer than the surrounding ocean, creating areas of low pressure over the continent. This temperature contrast generates monsoonal winds that blow predominantly from the southeast, drawing warm, moist air from the western Pacific Ocean into the region. This influx of moisture produces a rainy summer season. Additionally, this period is often accompanied by typhoons, which bring further torrential rains and strong winds to the area.123