初夏昆明罕见大暴雨分析

Analysis of An Early Summer Exceptionally Heavy Rainstorm over Kunming

１９８６年６月６—７日，云南昆明出现了１９５１年以来一次最大暴雨。天气学与诊断分析表明，初夏云南可产生单点局地大暴雨，量级与盛夏、秋季相当。５００ｈＰａ干冷糟东移，７００ｈＰａ双涡吸引旋转西移，地面弱冷空气诱发静止锋锋生，强垂直风切变，昆明上空出现正反环流圈是该次过程的主要特征，与低纬高原地区区域性大一暴雨特征不同。

ynoptic and diagnostic analysis have been performed for a heavy rainstorm in June, 6-7, 1986 in Kunming, Yunnan Province, of which is Kunming'S maximum daily precipitation since 1951. The results show that local heavy rainstorm may occur at single point in early summer in Yunnan Province,with its rainfall equals that in midsummer and autumn. The main characters of heavy rainstorm are as following. Dry cold trough at 500hpa moved eastward while double vortexes attracting and rotating moved westward. Weak cold air at surface induced stationary front with strong vertical wind shear,and therefore there existed a direct circulation and a counter circulation. These are different from the regional heavy rain and heavy rainstorm in low latitude plateau area.