气旋爆发性发展产生的北方冬季雷暴天气分析

分析了１９９０年１２月２１日和１９９６年１２月３１日沈阳市出现的两次冬季雷暴天气过程，结果表明：这两次冬季雷暴天气都是由于气旋在短时间内爆发性发展所产生的。气旋的爆发性发展对我国北方除造成大范围降雪外，还可产生强对流天气。而气旋以“Ｕ”型路径移动，入渤海后迅速发展；８５０、７００ｈＰａ爆发性的增温增湿导致其以上气层出现潜在不稳定层结，是预报冬季雷暴的一个着眼点。此外，城市热岛效应对触发冬季雷暴也起

Analysis on Winter Thunderstorm in the North Created by the Explosive Developing Cyclones

The analysis was conducted for two winter thunderstorms on December 21,1990 and December 31,1996 in Shenyang, Liaoning province. The results show that the two winter thunderstorms were due to cyclones explosive developing in short time. The explosive developing cyclones cause both large range of snow in northern area and strong convection weather. Cyclones moved along the path as the letter "U", got into Bohai sea and developed quickly. 850 and 700 hPa high explosive warming and explosive wetting caused potential instable stratification occurrence, they are the key to the winter thunderstorm forecast. In addition, urban heat island effect is very important to trigger off the winter thunderstorm.