东津水库“6·30”强降水过程分析及预报服务思考

Analysis of Precipitation Process in Dongjin Rese-rvoir On 6.30

本文利用常规气象观测资料、加密自动站雨量资料及FNL再分析资料,对比分析2020年6月29—7月1日东津水库持续暴雨天气从天气形势、水汽输送、热动力条件及雷达回波等方面。结果表明:入库水位上涨对强降水有较好的响应,但存在8~12 h的时间差;中低层辐合区和切变线的共同作用为强降雨天气提供了有利抬升条件,低层辐合和高层辐散形成的“抽吸作用”有效促进了低层水汽的上升运动;在强降水天气出现的过程中,垂直运动和位涡发展对库区暴雨落区与强度预报有一定的指示意义;雷达回波上,逆风区长时间出现和“列车效应”,对暴雨天气有良好的预报参考意义。

Based on conventional meteorological observation data,rainfall data of encrypted automatic station and FNL reanalysis data,the continuous rainstorm weather of Dongjin Reservoir from June 29 to July 1,2020 is compared and analyzed from the aspects of weather situation,water vapor transportation,thermal power condition and radar echo.The results show that the rise of water level in storage has a good response to heavy precipitation,but there is a time difference of 8~12 hours.The combined action of middle and low layer convergence zone and shear line provides favorable uplift conditions for heavy rainfall weather.The"suction effect"formed by low layer convergence and high layer divergence effectively promotes the rising movement of water vapor in the lower layer.In the process of heavy precipitation weather,the vertical movement and bit vortex development have some instructive significance for the heavy rainfall fall area and intensity forecast in the reservoir area.On the radar echo,the time of adverse wind area governor and"train effect",which have a good reference significance for rainstorm weather.