云南省一次局地短时强降水中尺度特征与诊断分析

利用常规观测、卫星云图、CINRAD-CC多普勒天气雷达观测、NCEP1°×1°再分析资料,对2013年云南中东部“5.23”短时强降水过程进行中尺度特征和成因研究,结果表明,该次过程前期全省晴热高温,早晨近地层“干暖盖”有利于不稳定能量积累,夜间700hPa切变线和低涡南下致使不稳定能量释放,产生强对流天气,强降水期间具有中等强度垂直风切变环境。强降水发生在对流层低层能量舌尖附近。强降水的水汽源地是700hPa西南气流从孟加拉湾输送的丰富水汽与850hPa层上偏东风输送的次强水汽中心。

MESOSCALE CHARACTERISTICS AND DIAGNOSTIC ANALYSIS OF A LOCAL SHORT-TIME STRONG RAINFALL IN YUNNAN PROVINCE

Based on conventional observations,satellite cloud images,CINRAD-CC Doppler weather radar observations and 1 degrees ×1 degrees long NCEP reanalysis data,the mesoscale characteristics and genesis of short-term heavy rainfall in the middle and eastern part of Yunnan Province in “5.23” in 2013 are studied.The results show that:In the early stage of this process,the whole province was hot and sunny,and in the morning,the “dry and warm cap” of the surface strata was conducive to the accumulation of unstable energy,and the 700 hPa shear line and the south of the vortex at night resulted in the release of unstable energy,resulting in strong convective weather.During heavy precipitation,there is a medium intensity vertical wind shear environment.Heavy precipitation occurs near the tip of the lower tropospheric energy tongue.The water vapor source of heavy precipitation is the center of abundant water vapor transported by southwestern flow of 700 hPa from the Bay of Bengal and the secondary strong water vapor transported by easterly wind over the 850 hPa layer.