夏季青藏高原常有低涡(下称高原低涡或高原涡)生成，是造成高原地区降水的主要天气系统，最近的统计分析表明移出高原的高原低涡不仅影响高原及周边省，并且大多数可造成四川盆地大雨以上的降水，还可造成云南大到暴雨。云南地处青藏高原东南麓，受青藏高原低涡的影响，使这里汛期暴雨天气频繁发生，并常造成洪涝灾害。对移出高原的低涡或低值系统对云南降水的影响过去并没有引起重视，由此产生暴雨的触发机制是什么也一直并不清楚。因此，通过资料统计分析、数值模拟及理论研究来揭示高原涡影响下的云南暴雨落区分布及日变化特征；揭示高原涡影响下云南暴雨的水汽来源、集中的特点。研究揭示高原涡与地形相互作用产生云南大雨暴雨的机制，为这类暴雨预报提供科学预报思路和预报着眼点。并为减少这类暴雨灾害造成的损失提供有效的科学理论基础，这也是云南暴雨预报业务的迫切需求。

In summer, the Tibet Plateau often produces low vortex (Hereinafter referred to as the plateau low vortex or plateau vortex) that is the main weather system that causes precipitation in the plateau area. Recent statistical analysis show that the plateau vortexes removed from the plateau not only affect the plateau and the surrounding provinces, and mostly make the heavy rainfall in the Sichuan Basin but also make the heavy rainfall in Yunnan. Yunnan is located on the southeast side of the Tibetan Plateau, under the influence of the Tibetan Plateau Vortex, where flood season rainstorm weather occurred frequently, and often cause floods. Previous studies were not paid attention to the influence of the vortex or low vortex system moving out of the Tibetan plateau on the precipitation in Yunnan. So it's unclear what the trigger mechanism of rainstorm is. Therefore, by the statistical analysis of data, numerical simulation and theoretical research, the distribution and diurnal variation characteristics of rainstorm in Yunnan and the characteristics of the water vapor source of Yunnan heavy rain under the influence of plateau vortex will to be revealed. The urgent need for Yunnan rainstorm forecasting is to study the mechanism of the interaction between the plateau vortex and the topography to produce the heavy rain and rainstorm in Yunnan, and provide scientific forecasting ideas and forecasting points for such rainstorm forecast. It can provide an effective scientific theoretical basis for reducing the losses caused by such storm disasters.