V-3θ图在一次特大暴雨预报中的应用

Application of V-3θ Chart in Forecasting of a Severe Storm

利用MICAPS 3版中自带的分析软件,分析了2009年7月17日夜间山东半岛一次副高边缘特大暴雨。结果表明,V-3θ图可以明显表示出本次特大暴雨的征兆。对流层顶层的超低温、对流层中层有冷空气侵入引发剧烈对流、低层水汽充沛是引发特大暴雨的原因。分析上游台站的V-3θ图可以判断水汽的来向和输送强度。海陆不同的下垫面分布是形成大暴雨的重要条件。分析V-3θ图的上述特征可以提前12h作出大暴雨以上的降水预报。

An analysis is made of a severe storm occurred on 17 July 2009 in the Shandong peninsula by using the V-3θ chart based on the analysis software of MICAPS（3rd edition）.The results show that the V-3θ chart can reveal the signs of severe storms.The ultra-low temperature at the tropospheric top,cold air intruding into the middle-level troposphere,the caused severe convection,and abundant moisture at lower levels are the causes of the severe storm.The V-3θ charts of the upstream stations can be used to estimate the direction and intensity of moisture transport.The difference in the underlying surface between sea and land is also an important cause of the severe storm.The characteristics of the V-3θ chart are useful in forecasting severe storms more than 12 hours in advance.