【摘要】 本文重点分析了2021年“7.20”河南暴雨水汽输送特征、水汽来源以及关键天气尺度系统。双台风“烟花”和“查帕卡”以及西太平洋副热带高压共同为“7.20”河南暴雨提供了充足的水汽条件。然而，就暴雨的水汽供应而言，仅以台风和西太平洋副热带高压的作用难以解释2021年7月20日发生的日降水量663.9 mm和1小时最大降水量201.9 mm的极端暴雨事实。水汽通量分析和LAGRANTO模式轨迹分析结果表明，20日在河南南侧形成了一个很强的经向水汽通量带（850 hPa以上），它与台风和西太平洋副热带高压引起的低层水汽通量带在河南附近汇合，为暴雨提供了最为充沛的水汽条件。我们强调，20日在河南以西地区上空发生了对流层顶反气旋式波破碎事件，它与台风协同作用，引发了河南南侧的强经向水汽通量，从而导致此次极端暴雨事件。更多还原

【Abstract】 This study analyzes the water vapor transportation features, water vapor sources, and key synoptic-scale systems of the “7.20” rainstorm in Henan in 2021. Double typhoons “In-fa” and “Cempaka” and the western Pacific subtropical high jointly provided sufficient water vapor conditions for the “ 7.20” rainstorm in Henan. However, the extreme rainstorm event, which has daily precipitation of 663.9 mm and 1-hour maximum precipitation of 201.9 mm on July 20, can hardly be explained only by the roles of typhoons and western Pacific subtropical high. Results of the water vapor flux analysis and trajectory analysis based on the LAGRANTO model show that a strong northward water vapor flux zone(above 850 hPa) was formed on the southern side of Henan on July 20, 2021. It then converged with the lowlevel water vapor flux zone facilitated by the typhoon and western Pacific subtropical high near Henan, thus providing the most abundant water vapor conditions for the rainstorm. This work emphasizes that the anticyclonic wave-breaking event that occurred at the tropopause to the west of Henan on July 20 triggered a strong meridional water vapor flux on the southern side of Henan and worked synergistically with typhoons, resulting in this extreme rainstorm.更多还原