永州市2020年2月13-16日寒潮天气过程分析

Analysis of Cold Wave Weather Process From February 13 to 16, 2020 in Yongzhou City

2020年2月13-16日,永州市出现了寒潮天气,24 h内降温最高达20℃,并伴有全市范围偏北大风,中北部出现短暂雨雪(雨夹雪)天气。本文利于常规地面、高空气象观测资料、自动站资料等对本次过程进行了分析。结果表明:本次寒潮过程中高纬呈两槽一脊型,新西伯利亚附近有阻高,阻高前横槽不断加深南落,槽后冷平流使冷空气堆积,冷涡中心强度强。中低层西南气流强烈发展,地面升温明显,有利于加大降温幅度。有冷空气影响,且降水条件满足时,分析各层温度、探空曲线、冷垫厚度、逆温层高度、厚度、地面温度等各要素对于判断雨雪的相态有很重要的指示作用。

From February 13 to 16, 2020, there was cold wave weather in Yongzhou City, with the maximum temperature drop of 20℃ in 24 hours, accompanied by northerly gale in the whole city. There was a short period of rain and snow(sleet) in the middle and north of Yongzhou. This paper is conducive to the analysis of this process with conventional surface and upper air meteorological observation data and automatic weather station data. The results show that there are two troughs and one ridge in the high latitude during the cold wave, and there is a blocking height near Novosibirsk. The cold advection behind the trough makes the cold air accumulate and the strength of the cold vortex center is strong. The strong development of southwest air flow in the middle and low levels and obvious surface temperature rise are conducive to increasing the cooling range. When there is cold air influence and the precipitation conditions are satisfied, it is very important to analyze the temperature of each layer, sounding curve, cold pad thickness, inversion layer height, thickness, ground temperature and other factors for judging the phase state of rain and snow.