黑龙江省一次局地强降水过程成因及预报难点分析  

Analysis on the cause and forecast difficulty of a local heavy precipitation in Heilongjiang

作　　者：孟莹莹[1] 赵玲[1] 

机构地区：[1]黑龙江省气象台,黑龙江哈尔滨150030

出　　处：《黑龙江气象》2017年第1期9-11,31,共4页Heilongjiang Meteorology

摘　　要：利用常规气象站观测资料和卫星云图资料,分析2015年8月8日发生在黑龙江省中西部地区一次局地对流性强降水量级预报偏小的原因。结果表明:中高层西南气流把干冷空气向黑龙江省中西部地区输送,并叠加在低层西南暖湿气流之上,热力抬升和低层切变辐合动力抬升共同作用,从而触发对流云团生成发展和局地短时强降水发生。强降水落区位于KI指数和高低空假相当位温差大值区叠加区域内;强降水发生在对流云团边缘云顶亮温梯度大值区以及TBB逐渐降低阶段。预报时只考虑低层暖湿气流偏弱,而忽略前期有持续性暖湿气流增温增湿使不稳定能量积蓄充足的特点,并且对500 hPa西南气流输送干冷空气这一罕见现象分析和认识不足,致使对黑龙江省中西部地区不稳定层结和短时强降水等强对流天气强度预报偏弱。Analyzes the reasons for the low level of local convective precipitation forecast in the middle and western regions of Heilongjiang province onAugust 8, 2015 with the observational data of conventional meteoro-logical stations and satellite cloud images.The results show that,the southwest airflow transport cold air to the top midwest area of Heilongjiang province, and superimposed on the low level southwest warm air, the interaction of thermal uplift and low layer shear convergence dynamic lifting trigger the occurrence and development of convective cloud formation and short local heavy rainfall. The strong drop area is located in the superimposed area of the KI index and the high and low altitude Equivalent potential temperature large value area. The strong precipitation occurred in the large area of the cloud top brightness temperature gradient and the decreasing stage of TBB. Considering the weak low-layer warm airflow only, however ignoring characteristics of accumulation of unstable energy because of increasing temperature and increasing humidity for continuous warmwet air and lacking awareness of rare phenomenon of southwest airflow conveying cold -dry air at 500 hPa, that leads to weak strength forecasting of Unstable stratification and short-time heavy precipitation in the central and western regions of Heilongjiang province.

关 键 词：降水量级预报 强降水过程 黑龙江省 中西部地区 暖湿气流 成因 卫星云图资料 对流云团 

分 类 号：P457.6[天文地球—大气科学及气象学] P458.121