午夜欧美大片免费观看,欧美激情综合五月色丁香,亚洲日本在线视频观看,午夜精品福利在线

On the basis of the atmospheric circulation background and the objective diagnosis of physical quantities with newgeneration weather radar data at Xifeng, an analysis is made of the shorttime severe rainstorm event, induced by the Hetao vortex, in Huanxian of Gansu Province on 24 July 2007. The results show that there existed a deep positive vorticity field corresponding to the Hetao vortex in the vertical section; the echo reflectivity factor is greater than 50 dBz before the hail storm, with the strong echo center in the vicinity of the 0 ℃ layer, and there was no obvious “jumping” feature with altitude; the high value centers of horizontal convergence on the radial velocity echo image (≥±20 m/s) were highly active in the layer of 2 to 7 km; there were significant “jumps” of cloud top heights; the area of VIL being greater than 45 kg〖DK〗·m-2 expanded quickly, which has indicative significance for the earlywarning and monitoring of shortrange severe weather and hail suppression operation.