1998年6月28日～7月2日淮河流域暴雨分析

ANALYSES OF HEAVY RAIN IN HUAIHE RIVER BASIN DURING 28 JUNE—2 JULY, 1998

摘要: 文中对比分析了1998年6月28～29日和7月1～2日淮河水循环试验期间两次特大暴雨过程的天气形势、红外卫星云图上降水云系的特征及其水汽来源。结果表明:(1)6月底的暴雨是一次东移的西南低涡引发的暖性切变线降水,β中尺度对流系统起主要作用。7月初的暴雨过程是一次移动缓慢的锋面降水,锋面上有中尺度的云团活动,这是一次大中尺度系统相互作用的结果。(2)两场特大暴雨的水汽源地都为中国南海北部地区,而强度达到18～22m/s的西南低空急流是水汽的输送带。

Abstract: The features of cloud system and vapor sources of two heavy rain cases on 28-29 June 1998 and 1-2 July 1998 during the GAME/HUBEX Experiment were analyzed and compared by the satellite infrared images and the diagnostic technique.The results showed that:(1) The precipitation at the end of June is produced by the meso-β-scale convective system,which was trig gered by a warm shear associated with southwest vortex.The precipitation at the beginning of July was associated with the interaction between a cold front moved slowly and some MCSs embedded in this cold front.(2) The vapor sources of these two cases both were the north of the South China Sea,and the strong southwest low-level jet (about 18 22m/s) was the conveyer belt of moisture.