| 摘要: |
| 本文利用观测资料、广西中尺度自动站资料及FNL资料，分析了2022年2月中下旬影响桂北的一次低温雨雪冰冻天气。分析表明：（1）过程期间中高纬为两槽一脊型，乌拉尔山高压脊强盛发展，东移缓慢；脊前的强冷空气与南支槽前的西南暖湿气流在华南交汇为此次低温雨雪天气的产生提供了有利的环流形势。此次过程产生的重要原因是低层强锋区稳定维持。（2）从降雨转为雨夹雪，温度垂直结构，逆温层的高度、厚度及强度、0度层的高度，近地面融化层的厚度、地面温度都有显著变化。（3）持续的中低层水汽输送和辐合利于冰冻雨雪天气的发生及维持（4）湿层厚度的变化对雨雪相态的转化有一定的指示意义。 |
| 关键词: 低温雨雪；强锋区；锋面逆温，雨雪相态 |
| DOI： |
| 投稿时间：2022-08-30修订日期：2022-11-14 |
| 基金项目:广西自然科学基金项目（2020GXNSFBA297129）资助;柳州市科技计划项目（2020NBCA0801） |
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| Cause analysis of a low-temperature?and?freezing?rain weather process in Guangxi in mid and late February 2022 |
| liyaqin |
| (Liuzhou meteorological bureau) |
| Abstract: |
| Using the observational data, Guangxi mesoscale automatic station data and NCEP reanalysis data, this paper analyzes the low-temperature rain, snow and freezing weather affecting Guangxi in the middle and late February 2022. The results show that: (1) during the process, the middle and high latitudes are two troughs and one ridge, and the Ural Mountain high-pressure ridge is strong and develops, moving slowly eastward; The strong cold air in front of the ridge and the southwest warm and humid air flow in front of the South Branch trough intersected in South China, providing a favorable circulation situation for the occurrence of this low-temperature rain and snow weather. The long-term maintenance of 850hPa strong front area is one of the important reasons for this process. (2) From rainfall to sleet, the vertical structure of temperature, the height, thickness and intensity of inversion layer, the height of 0 degree layer, the thickness of near ground melting layer and ground temperature have obvious changes. (3) The continuous transportation and convergence of water vapor in the middle and low levels are conducive to the generation and maintenance of freezing rain and snow weather (4) the change of wet layer thickness has a certain indicating significance for the transformation of rain and snow phase. |
| Key words: now and freezing weather；Strong frontal zone；Frontal inversion；Rain and snow phase |
