豫东地区“6.3”与“7.17”两次致灾大风雷达资料对比分析

利用加密自动站常规、非常规资料和多普勒雷达资料,分析了2009年6月3日(简称"6.3"过程)和2010年7月17日(简称"7.17"过程)在豫东地区出现的大范围强对流、大风天气过程。结果表明,"6.3"和"7.17"过程虽然都有高空槽和槽后西北气流引导北方冷空气南下,使中高层气温迅速下降,造成大气层结的极不稳定和高低空风的垂直切变,进而高空动量下传,形成强对流的发生、发展、维持和传播。雷达径向速度和风廓线显示,"6.3"过程"弓形"出现了强回波区并位于回波区前沿,其移动速度快,具有径向风速辐合等飑线特征;"7.17"过程则是在中尺度涡旋云系中形成多个局地对流旺盛的单体,最终造成强降雨、雷电和局地强风暴等强对流天气。

Contrast of Radar Information between Two Destructive Gales Occurred in the East of Henan Province on June 3 and July 17

Using the conventional and non-conventional data,the gales occurred in the east of Henan Province on June 3,2009(’6.3’ process for short) and July 17,2010(’7.17’ process for short) are analyzed.The result shows that though the upper-level trough and the northeast wind behind trough cause from cold air of Northern China to south both in ’6.3’ and ’7.17’ processes,the temperature in middle troposphere rapidly fell,which cause the instability of atmosphere and the vertical wind shear of upper and lower tropospheres,and then the downward transport of momentum cause the occurrence,development,maintenance and spread of strong convection.According to radial velocity of radar and wind profile,’6.3’ process is of such squall line features: The strong echo region is in the front of echo region and likes a bow,moving speed of the echo is fast,and convergent radial wind.However,’7.17’ process forms much strong local convection cells in mesoscale vortex cloud system,contributing to heavy rain,thunder and lightning,severe local storm and so on.