台风“麦德姆”引发浙江暴雨的成因分析

利用NCEP再分析资料、MICAPS资料、常规自动站资料对台风“麦德姆”过程进行综合分析，主要对其在浙江中南部和西部造成的暴雨成因作诊断分析.结果表明：（1）副高外围气流为麦德姆移动路径起着关键的引导作用；（2）暴雨区上空较强的水汽通量、高温高湿的湿能量积聚、不稳定的大气层结以及持续长时间的上升运动都为暴雨发生提供了有利条件；（3）根据湿位涡分析，本次过程是一次对流不稳定和斜压不稳定均存在、以对流不稳定为主的台风暴雨过程.暴雨区发生在MPV1负值中心附近，尤其700 hPa的MPV1值指示效果最好，且降水强度与该值有正相关性，中低层深厚的MPV1负值区配合其高层正值区有利于暴雨发生，此外MPV2表征的大气斜压性也与降水强弱呈正相关关系.

Causation analysis of the heavy rain in Zhejiang Province caused by typhoon “Matmo”

NECP reanalysis data, MICAPS data and the data of general automatic stations are used to synthetically analyze the process of typhoon “Matmo”, mainly diagnostically analyze the reason of the heavy rain in south central and western Zhejiang Province. The results show that:（1）The air flow on the peripheral of subtropical high plays an important role in leading the moving path of “Matmo”;（2）The fairly strong water vaporflux，accumulation of moist power with high temperature and high humidity，unstable atmospheric stratification and the persistent ascending motion above the heavy rain area all provide favorable conditions for the occurrence of the heavy rain;（3）According to the analysis on moist potential vorticity，this heavy rain process caused by typhoon has both convective instability and baroclinic instability, but mainly based on convective instability. The heavy rain area was neighbouring the MPV1 negative center, especially the MVP1 value in 700 hPa has the best indication effect. And the precipitation intensity has a positive correlation with the MVP value.The deep thick MPV1 negative value area in the middle low level with the positive area in high level is beneficial to the occuring of heavy rain.In addition, the atmospheric baroclinicity that MPV2 represents also reveals a positive correlation with the precipitation intensity.