深圳市前汛期西风带大暴雨天气形势特征

对1978～2008年深圳市前汛期西风带大暴雨期间的500、850 hPa和地面环流形势进行统计分析,发现深圳市前汛期大暴雨过程多由西风带系统引起,占总数的77%。4～6月均可出现大暴雨,6月份最多,4月份次多,5月份最少。深圳前汛期西风带系统大暴雨过程按天气形势特征分为锋面低槽和暖区两类,其中锋面低槽类又分东北低涡(低槽)型和西南低涡型。

Characteristics Analysis of Synoptic Situation on Heavy Rainstorms induced by Westerlies in First Flood Season in Shenzhen

Through statistical analysis on the weather situation at the levels of 500hPa,850hPa and ground during heavy rainstorm events in first flood season of Shenzhen from 1978 to 2008 ,it is revealed that 77% heavy rainstorms were induced by weather systems in westerly belt in first flood season in Shenzhen. Heavy rainstorms can occur from April to June,in which June take the largest proportion, then April followed by May. Heavy rainstorm processes can be classified as Type frontal trough and Type warm -sector vortex, and Type frontal trough can be further divided into northeast vortex （trough） and southeast vortex.