利用常规气象观测资料、加密自动气象站风场资料及雷达回波资料对2016年8月7—8日大连地区一次漏报的局地大暴雨过程的中尺度特征进行分析,并探讨了加密自动气象站数据的应用.结果表明:2016年大连地区此次局地大暴雨过程T639、欧洲和日本3种数值模式预报结果差异较大,均漏报了暴雨和大暴雨量级降水.环流形势和物理量场对此次暴雨过程的暴雨与大暴雨量级降水落区均无明显预报指标,而卫星云图上有TBB<-45 ℃的中尺度对流云团与强降水区域对应;最强短时强降水区域雷达回波上有对流风暴单体,最大回波强度达55 dBz,高度上升至4 km,50 dBz强回波从地面伸展至6 km高度,且强度均匀,为低质心强降雨回波;同时,由加密自动气象站风场资料可知,提前1h左右强降水落区有中小尺度辐合线形成,最强区域为中尺度气旋,这个指标配合雷达回波和卫星云图资料可以在环流形势、物理量场和数值预报均无明显特征时,作为局地大暴雨预警的指标.%Using the conventional meteorological data,wind field of automatic weather station(AWS)data and weather radar imagery,the meso-scale feature of a missing report local rainstorm was analyzed.The applications of the AWS data were discussed as well.The results show that the outputs from the T639,European and Japanese nu-merical weather prediction models demonstrate obvious deviations,and they all fail to predict heavy rain and rain-storm scenarios.Few evident forecasting indices on the background circulation and physical parameter fields can be found to indicate the heavy rain and rainstorm events.While the satellite imagery shows that the meso-scale con-vective cloud clusters with TBB(Temperature of Black Body)less than-45 ℃ consist with the heavy rainfall re-gion.The maximum rainfall intensity region corresponds to a single-cell convective storm with the maximum echo of 55 dBz reaching 4 km and the 50 dBz echo reaching up to the height of 6 km.Its intensity is uniform.The entire feature indicates it is a low-mass-center strong rainfall radar echo.Meanwhile,the formation of a meso-scale con-vergence line is identified from the AWS data in the same region as the heavy rainfall happens one hour ago.The maximum convergence region shows a meso-scale cyclone feature.This feature along with the weather radar and satellite imageries can be used as an indicator for the local rainstorm alert when there is little convincing general circulation,physical parameter and the NWP output information.
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