2021-12-26江西雨雪天气回波特征分析

Analysis of echo characteristics of rainy and snowy weather in Jiangxi on December 26,2021

为了更好地做好市县两级雨雪天气精细化监测预警工作,文章使用自动气象站数据、MICAPS天气图和江西WebGIS雷达拼图等资料,采用多种分析方法,对2021-12-26江西雨雪天气进行分析,结果表明:江西处于500hPa槽前偏西气流中,100hPa有出流区,850hPa有东北气流,地面弱风区中;南昌层结趋于稳定,在弱的暖平流环境下,反而有利于雨雪天气的形成;雨的回波呈絮状结构,CR强度20~35dBZ;雪的回波呈片状结构,CR强度10~25dBZ;雪的回波顶ET在6km以下,雨的回波顶ET可达9km;雪的垂直积分液态水含量VIL几乎观测不到,雨的VIL在10kg/m^(2)以下;雨雪回波垂直高度较低,20dBZ回波顶高在5km以下。这些研究结果对市县两级开展雨雪天气监测预警和预报服务提供指导和参考。

In order to better carry out the fine monitoring and early warning of rain and snow weather at the city and county levels,the rain and snow weather in Jiangxi on December 26,2021was analyzed by using the data of automatic weather station,MICAPS weather map and Jiangxi WebGIS radar puzzle.The results show that Jiangxi is in the west air flow in front of the 500hPa trough,and there is an outflow area at 100hPa,a northeast air flow at 850hPa and in the weak wind area on the ground.The stratification in Nanchang tends to be stable.Under the weak warm advection environment,it is conducive to the formation of rain and snow weather.The echo of rain is in flocculent structure,and the CR intensity is 20~35dBZ.The echo of snow is in flake structure,and the CR intensity is 10~25dBZ.The echo top ET of snow is less than 6km,and the echo top ET of rain is up to 9km.The vertical integral liquid water content VIL of snow can hardly be observed,and the VIL of rain is less than 10kg/m^(2).The vertical height of rain and snow echo is low,and the top height of 20dBZ echo is less than 5km.These research results have been guiding significance for rain and snow weather monitoring,early warning and forecasting services at the city and county levels.