利用常规高空探测资料,分析了2000—2012年4—6月850 hPa层位势高度差异常(上海宝山或大陈岛站850 hPa层位势高度值比贵阳站大7 gpm或以上)形势下低空环流与江西降水的关系.结果表明,这种形势下,700 hPa高度层上均有西南低涡活动.近50%的个例江西省上空850 hPa层出现风速16 m/s以上的低空西南急流,约40%的个例有切变线活动；若去除850 hPa无切变线影响和切变线出现较晚的情形,江西省出现10站以上暴雨过程的比例为85.7%.% The conventional observation data are used to analyze the relationship between low-level circulation and the precipitation in Jiangxi province under the background of unusual 850 hPa-geopotential height difference (the geo-potential height in Baoshan in Shanghai or in Dachen Island is 7 gpm larger than that in Guiyang). Under such situation there has southwestern vortex at 700 hPa, nearly 50% of the cases show low-level southwestern jet with 850 hPa wind speed more than 16 m/s over Jiangxi and about 40% of the cases show shear lines. The occurrence probability of heavy rainfall at more than 10 stations is 85.7% if there is no 850 hPa shear lines or the shear lines appear too late.
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