2005年6月18-22日浙南持续性梅雨锋暴雨过程诊断分析

Diagnostic Analysis of a Continuous Meiyu Front Heavy Rainfall Event From June 18 to 22,2005 in Southern Zhejiang

利用NCEP 1°×1°的6 h再分析资料、常规观测资料和逐小时加密雨量资料,对2005年6月18-22日浙江省中南部地区出现的一次持续性梅雨锋暴雨过程进行诊断分析。结果表明:此次持续性梅雨锋暴雨过程是在两槽一脊的大环流形势下,由中低层切变、西南涡和冷空气共同影响造成的;过程具有明显的中尺度特征,12个中尺度雨团的持续生成东移导致了暴雨的发生。正涡度大值中心值的强度和中尺度雨团的强弱以及暴雨落区有较好的对应关系;垂直速度以及垂直螺旋度的强弱和中尺度雨团的强度变化一致。急流核的出现导致水汽辐合明显加强,从暴雨区和急流核的位置配置来看,暴雨区出现在急流核的左侧。

Based on the reanalysis data （1°×1°, 4-times-a-day＇ s） of NCEP, the conventional data and hourly intensive rainfall data, a diagnosis of continuous rainfall event from June 18 to 22, 2005 in southern Zhejiang is made. The result showed the rainfall event was caused by the low-level shear, south- west vortex and cold air on the circulation pattern of the two troughs and a ridge, and had obvious me-soscale characters. The 12 mesoscale rain cluster which continuous generated caused the heavy rainfall The large value of vorticity center can reflect the strong of mesoscale rain cluster and the area of heavy rainfall. The strong of vertical speed and vertical helicity were consistent with the mesoscale rain cluster. The jet-cores caused the water vapor increased. From the point of view the configuration of rainfall areas and jet-core location, the heavy rainfall happened on the left of the jet-cores.