【摘要】 通过对2007年7月24日发生在陕西省的一次"干"对流风暴过程的分析,发现这次对流性风暴有2个主要特点:①风暴区的水汽输送和辐合均比较弱;②风暴发生在高空急流入口区内和低空急流轴左前方3~5个纬距内。高、低空急流耦合激发了急流次级环流的产生和发展,急流次级环流对风暴又产生了正反馈作用;地面中尺度涡旋是由急流次级环流上升支引起的。更多还原

【Abstract】 In this study,a mesoscale analysis of a "dry" convective windstorm that occurred in Shaanxi Province on July 24,2007 was conducted.The preliminary results were as follows: The vapor transfer and convergence over the windstorm area were weak.The windstorm occurred in the area under the upper-level jet stream within 3 to 5 latitudes left forward of the axis of the low altitude jet stream.The formation and development of the jet secondary circulation were excited by the coupling of the upper-level and low altitude jet streams,and the jet secondary circulation provided positive feedback to the windstorm.The circulation provided a strong impetus to the continuing uplift force that induced the strong convective weather,and the "Dry" convective windstorm occurred in a rapid rise in a subbranch of the circulation.The rising branch of the Jet secondary circulation resulted in a surface mesoscale vortex.更多还原