青海省短时强降水环境场特征和物理量诊断分析

利用常规气象资料、NCEP再分析资料和卫星资料，对青海2006～2010年2、6和6h以上3个时段短时强降水（1h≥25mm）天气过程的环境场和物理量进行了诊断分析。结果表明，多发区在青海南部和东部，7和8月为峰值区；6h以下时段内强降水发生的主要触发机制是中尺度低压和辐合线、干线，而6h以上是短波槽和切变线；强降水发生前，500hPa有强的水汽辐合，相对湿度大，有强烈的垂直上升运动；中低层风场的垂直风切变强，且风随高度顺转，发生在6h内的短时强降水天气的垂直风切变最弱，

Diagnosis and Analysis of Short Heavy Precipitation on Environment Field and Physical Quantity in Qinghai Province

Based on conventional observational data, the NCEP reanalyzed and satellite data, a diagnosis was carried out on three different time short period（2 h, 6 h, above 6 h） heavy precipitation process during 2006-2010 occurred in Qinghai. The results showed that the high zones is in southern and eastern of Qinghai, meanwhile, July and August is two peak; the main trigger mechanism of heavy precipitation is me-soscale depression and convergence line, trunk below 6 h, it is shore wale trough and shear line above 6 h; before heavy precipitation occurs, there is water vapor convergence, great relative humidity and strong updraft on 500 hPa; vertical wind shear become intense in middle anti low levels, it is the weakest in 6 h, meanwhile, wind follow height veering.