The typical large scale circulation model of persistent heavy rain in Jiangxi

With the 500 hPa daily weather images over Eurasian region from 1961 to 2010,the large scale weather patterns of 74 persistent heavy rain cases in Jiangxi were analyzed.Based on the analysis results,the large scale circulation model for Jiangxi persistent heavy rain was established.In this model,two blocking high located in the west side of Ural Mountains and the west side of the Okhotsk Sea respectively.There was a low vortex in the Northeast China,and a deep trough(North China trough) lay from the center of the low vortex to the Jiangxi area.The west Pacific subtropical high located over western Pacific region at low latitude,its ridge line lied near 20°N,west ridge point situated near 110°E and584line was at north side of the subtropical high loacated near 27°N.The cold dry air at rear of North China trough continuously converged with the warm wet air in the northwest of West Pacific subtropical high over Jiangxi,which provided the favourable conditions of water vapor transportation and convergence uplift for persistent heavy rain in Jiangxi.Both the 500 hPa daily weather images and NCEP data weather patterns indicated that this model was applicable.