驻马店一次冰雹天气过程的诊断分析

Diagnostic Analysis on a Hail Storm Occurred in Zhumadian Area

从天气背景入手,运用常规观测资料、四要素站、多普勒天气雷达等资料,讨论了2010年6月18日出现在驻马店市驿城区的冰雹天气的大气不稳定层结、水汽条件和上升运动等特点,并结合多普勒雷达探测资料对冰雹云的回波特征做了分析。结果发现,这次降雹过程高空形势表现为冷涡型,冰雹落区主要在地面辐合线两侧;大气层结的不稳定性在K指数、SI指数、CAPE值、θse和风随高度的变化等方面均表现明显,0及-20℃层高度也有利于冰雹的产生,强的垂直上升运动和深厚的湿度大值区也为冰雹的产生提供了有利的环境条件;冰雹回波面积小但强度大,伴有V型缺口和强辐合区,强回波下方由上升气流造成的弱回波区表现明显。

According to the weather background of the hail storm,by using conventional observational data,four elements stations and Doppler radar detection data,the unstable atmospheric layer,the moisture condition and the upward motion character etc.that caused the hail storm weather on June 18,2010 in Zhumadian were discussed,and combined with the Doppler radar detection data,hail storm cloud echo characters were analyzed.It was found that the high-altitude situation is a cold-vortex,hail storm fall mainly along the surface convergence line.The K index,SI index,CAPE value,and the wind changes with height all showed clearly that the atmospheric layer is instable.0 ℃-layer-height and-20 ℃-layer-height are also conducive to the production of hail storm.Strong upward motion and deep vertical humidity values also provide favorable environmental condition.The hail storm echo area is small,but strong,accompanied by V-notch and strong convergence zone,and there is the weak echo region caused by the rising air below the strong echo.