登封2007年春季大到暴雨的特征分析

Characteristic Analysis of the Rainstorm over Dengfeng in 2007 Spring

利用NCEP提供的再分析资料(Global Final Analyses),对2007年3月3日登封市大到暴雨天气过程从动力和热力条件、水汽输送、湿Q矢量等方面进行分析,结果表明:这次降水过程的两个主要降水时段都出现在次级环流的垂直运动上升区内;暴雨过程中登封上空中低层维持一高能区;温度平流值陡降,导致这次降水过程结束和强降温天气的发生;整个暴雨过程登封维持着通畅的水汽通道和较强的水汽辐合,水汽辐合中心区对应降水集中时段。

Based on the final analysis data of NCEP, the rainstorm occurred in Dengfeng on March 3, 2007 is analyzed from the following aspects： dynamic and thermal energy conditions, water-vapor transportation, wet Q vector and so on. The result shows ： two of the main precipitation time interval both appear in the vertical rising area of the secondary circulation; a high energy region maintains in low-altirude layers; the end of precipitation process and occurrence of strong temperature decreasing are caused by sudden drop of temperature advection; unobstructed water vapor channel and strong water vapor convergence maintain over Dengfeng in the whole process, and water vapor convergence central area is corresponding to the main precipitation time interval.