台风"泰利"影响庐山连续特大暴雨成因分析

应用NCEP再分析资料和观测资料,对2005年9月初庐山连续特大暴雨的成因进行了分析.分析结果表明,因北方高压脊的阻挡,“泰利“低压在赣西北停滞,导致庐山出现持续强降雨.强降雨期间,高层流线散开,低层流线汇合;“泰利“登陆后西北行时,低压西部有冷空气补充;庐山低层并未直接受冷平流影响;对应2次暴雨极值的出现,庐山高、低空的动力、热力、水汽和不稳定条件,均有利于降雨加大,高山地形有利于暖湿气流抬升,从而导致这次庐山降雨加强.

CAUSES ANALYSES OF LUSHAN PERSISTENT STORM INFLUENCED BY THE TYPHOON "TAILIM" CIRCULATION

A continual heavy rain took place at Lushan at early September 2005.With the observation and reanalysis data of NCEP,a study is made to discuss the reasons why it happened.The conclusions are reached as follows: It began to rain at Lushan when the landed and reduced vortex "TAILIM" moved to the south of Jiangxi province,and when Lushan located at the northeast of "TAILIM",the rain was strengthened.Because there was a stable ridge in the north,"TAILIM" stayed a long period at the southwest of Lushan,which led to the continual heavy rain at Lushan.The inverted trough at the north of vortex was the triggering system of the heavy rain,stream lines dispersed at high level but converged strongly at low level when it kept raining hard at Lushan.Cold air converged into "TAILIM" continually from the west after "TAILIM" landed and moved to the northwest,but the cold air advection did not influence Lushan during the heavy rain.The changes of physical factors at Lushan show that the conversions of dynamical,thermal,moist and unstable conditions are coinciding with the occurrence of peak rainfall of Lushan.