“2007.08.13”汕头强雷暴天气雷达回波特征分析

根据2007年8月13日汕头强雷暴天气的雷达资料和闪电定位资料,利用统计和对比分析的方法,分析闪电活动与雷达回波之间存在的关系。结果表明:强回波面积与闪电次数具有显著相关关系,闪电活动相对于强回波面积的变化有10 min的提前量;闪电发生的位置变化与强回波的移动密切相关,而速度回波更清晰地反映和预示雷达回波的移动趋势。基本速度图中的辐合区也是闪电活动频繁的区域,雷暴发生前40 min,风廓线图中出现断裂的双干区,随后该双干区自上而下迅速遭到破坏。双干区的出现和破坏是雷暴天气产生的先兆特征。

Radar echo characteristics of severe thunderstorm weather on August 13,2007 in Shantou,Guangdong province

Based on Doppler radar data and lightning location system data of severe thunderstorm weather on August 13,2007 in Shantou,Guangdong province,the relationships between lightning and radar echo were analyzed by statistical method and comparative analysis method.The results indicate that there is a distinct correlation between strong echo areas and lightning times.Compared with the changes of the strong echo areas,the lightning activities are ahead of 10 min.The changes of lightning positions are relative to the strong echo shifts,and velocity echo can predict the trend of radar echo shift.Lightning activities often occur in convergence areas.Double-dry regions appear ahead of 40 min in the wind-profile figure before thunderstorm happens,and then double-dry regions are destroyed rapidly from up to down.The appearance and breakage of double-dry regions are the premonition of thunderstorm weather.