2020年11月18—19日通辽市大暴雪成因分析  

The Cause Analysis of Heavy Snowstorm in TongLiao from November 18 to 19,2020

作　　者：赵梅兰 Zhao Meilan(Tongliao Meteorological Bureau,Inner Mongolia Tongliao 028000)

机构地区：[1]通辽市气象局,内蒙古通辽028000

出　　处：《内蒙古气象》2022年第3期9-14,共6页Meteorology Journal of Inner Mongolia

摘　　要：利用常规观测资料、NCEP再分析资料、多普勒雷达资料等多源观测资料,对通辽市2020年11月18—19日大暴雪过程进行成因分析。结果表明:高空低槽产生的高空强辐散与地面倒槽增强的辐合相互作用以及高、低层系统的适宜配置是产生此次大暴雪的有利环流形势。中层低涡的形成和加强以及低空强暖湿急流的适宜配置也是强降雪产生的一个有利因素。发展强盛的气旋东移过程中入海卷入大量水汽再北上,海上丰沛水汽沿着强低空急流输送,提供了丰沛的水汽。低层850 hPa以下有冷平流,中层西南暖湿气流在低层冷垫上爬坡,不稳定能量释放,是强降雪产生的动力作用。雨或雨夹雪期间出现明显的“零度层亮带”,雨夹雪转为雪后“零度层亮带”消失。By using the routine observation data, NCEP reanalysis data and Doppler weather radar data, this paper analysis the reason of a heavy snowstorm in TongLiao in november 18—19,2020. The result show that a high-altitude strong divergence forcing caused by upper trough,the convergence of the ground inverted trough interaction and proper configuration of high and low level system, it is the favorable circulation situation which produces this heavy snow storm.Formation and strengthening of mesoscale vortex in the middle layer and proper configuration of low-level strong warm-wet jet, it also is a favorable factor for heavy snowfall.During the eastward movement of the developing strong cyclone, a large amount of water vapor was sucked into the sea and then the cyclone moved north. Abundant water vapor from the sea is transported to our city along the strong low level jet stream and provide an abundance of moisture. The mid-level reflux warm moist air flow over the cold pad and release unstable energy, it is the power of heavy snowfall. The“zero layer bright band”has a good indication to the precipitation phase state, corresponding to the occurrence of rain or sleet.

关 键 词：暴雪 低槽 气旋 急流 水汽 

分 类 号：P426.63[天文地球—大气科学及气象学]