2001—08—07河南省局地强风暴天气过程分析

2001年8月7日冷锋过境前河南中部出现了局地雷雨大风，冰雹，龙卷及短时强降水天气过程。分析结果表明：地面高温高湿，为强风暴的发生提供了热力条件；高层冷平流，低层暖平流提供了层结条件；地面流场上风向辐合提供了动力条件。强风暴出现在高能区，并在高能区传播和移动。雷达回波的反射率因子特征为强度强，高度高，移速快；强回波位于移动方向前方，弱回波位于移动方向后方。平均径向速度场特征为辐合系统和气旋性辐合系统，垂直剖面图上，低层有明显的辐合界面。

An Analysis on Local Powerful Storm Weather Process in HenanProvince on Aug 7,2001

On Aug 7,2001,local thunder shower and gale, hail tornado and short-range precipitation weather process had appeared in central Henan before a cold front passed. The following are analysis outcomes: High temperature and humidity on surface offered thermal conditions for the powerful storm. Cold advection on upper lever and warm advection on low lever offered stratified conditions.Wind concentrate on surface flow field offered dynamic conditions. The powerful storm appeared in high energy area spreader and moved in it. The characteristic of reflectivity gene of radar echo are powerful intensity high height?quick move speed; Powerful radar echoes were on the frontage of move direction but the weak were on the backside of move direction. The mean meridional speed field are concentrated systems and cyclone concentrated systems, Obvious concentrated interface on low-level on the vertical cross-section.