Abstract:

Diagnostic analysis on the torrential rain process on 9 July 2012 in southern region of Shandong Province was made by using conventional meteorological data，the intensive observations of automatic weather station， FY－2E satellite images，NCEP reanalysis data and Doppler weather radar．The results show that the heavy rain occurred under the circulation form of two high confrontation ．The location and intensity of the upper and lower－level jet streams influenced rainstorm area and rainfall intensity． The occurrence and development of ground meso － scale cyclone was the direct cause of the torrential rain．The strengthening of the high pressure system over the west of Lake Baikal guided the cold and dry air from its north into southern area of Shandong，which cased ground convergence to strengthen and triggered the initial meso － scale cyclone generating． Cold and warm air over the storm area merged and triggered the release of unstable energy，which directly resulted in the torrential rain． The VWP product of Doppler radar could be a good catch for cold and warm air activities．

Key words: torrential rain, meso － scale cyclone, cold and dry air, triggering mechanism

摘要：

应用常规气象观测及地面加密自动站观测资料FY－2E红外云图、NCEP再分析资料和多普勒雷达资料，对2012年7月9日山东南部一次大暴雨过程进行诊断分析。结果表明:这次鲁南大暴雨发生在2高对峙的环流形势下；高、低空急流的位置和强弱影响大暴雨的落区和降水强度大小;地面、β中尺度气旋的发生发展是造成本次大暴雨的最直接原因；贝加尔湖以西高压系统加强引导其北部的干冷空气南下进入鲁南地区是地面辐合加强生成初始β中尺度气旋的触发机制;冷暖空气在暴雨区汇合并触发不稳定能量释放是造成本次大暴雨的根本原因;多普勒雷达VWP产品可以很好地捕捉冷暖空气的活动情况。

关键词: 大暴雨, 中尺度气旋, 干冷空气, 触发机制