江西安福县一次局地强对流天气过程成因浅析

对2006年6月26日江西安福县强对流天气过程的天气形势、雷达回波资料和对流参数等进行了分析。分析结果表明,本次过程中高层有明显的低槽和切变线东移,中低层具备较好的水汽条件;对流有效位能不断积累,各种不稳定指数不断增大,为这次强对流天气过程提供了有利的热力条件;在强对流区,地面有中尺度涡旋生成;强对流发生在强反射率因子与强逆风区(伴随强辐合与中气旋系统)同时出现的区域,且回波经过山区迎风坡时明显加强,表明地形对强降水分布有明显影响。

Analysis of a Local Severe Convective Weather Process at Anfu County

The severe convective weather process on June 26,2006 at Anfu county was analyzed with synoptic situation,radar data and the convective parameters.The result indicates that,there were distinct trough and east-moved shear line in mid-high layers,and advantage humidity in low-mid layers.Indicated from convective parameter change of all levels,the accumulation of convective available potential energy,the increase of all kinds of stability indexes,provided the advantageous thermal condition for this severe convective weather process.In the severe convective region,there was meso-scale vortex on the surface.The severe convection occurred in the area where both strong reflectivity and adverse wind regions(associated with strong convergence and mesocyclone system) appeared simultaneously,moreover the echo strengthened after passing the windward slope,which indicated that the terrain has obvious influence on the distribution of heavy rainfall.