| 摘要: |
| 2018年7月22日三都县城出现局地短时大风,利用实况观测资料、多普勒雷达资料及 FNL再分析资料对此次过程的气象要素变化、环境场、雷达、地形影响进行分析,发现：此次过程大形势不具备形成大风的条件,是午后热对流形成的雷暴大风；在大风发生前5天三都县城气温维持35℃以上的高温天气,气压呈现降低的趋势,大风发生前1天三都与周围站点气压差开始增加；此次大风雷达回波生成于较高层次,在大风发生前出现了明显的反射率因子核心降低和中层径向辐合,有利于地面大风的出现,同时地形“狭管效应”与下垫面的影响使得河面上风力加大。 |
| 关键词: 雷暴大风;要素变化;雷达;地形 |
| DOI： |
| 投稿时间：2018-10-17修订日期：2018-12-29 |
| 基金项目: |
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| Analysis of the Gale in Sandu,Guizhou on July 22 |
| ZHAO Jie,PAN Qixue,HUANG Guidong |
| (Qiannan Meteorological Bureau) |
| Abstract: |
| On July 22, 2018, there was a short-term strong wind in Sandu County. The live observation data, Doppler radar data and FNL reanalysis data were used to analyze the changes of the meteorological element, environmental field, radar and terrain. It shows that the big situation of this process does not have the conditions for the formation of strong winds, and it is the thunderstorm wind formed by the afternoon heat convection; 5 days before the strong winds the temperature of Sandu County maintains the temperature above 35 ℃ , the pressure is decreasing. 1 days before the strong winds The difference in air pressure between the Sandu and the surrounding sites began to increase; the gale radar echoes were generated at a higher level, and before the occurrence of strong winds, there was a significant reduction in the core of the Reflectivity factor and the radial convergence of the middle layer, which was conducive to the occurrence of ground winds. At the same time, the influence of the “venturi effect” and the underlying surface of the terrain makes the wind on the river surface increase. |
| Key words: Thunderstorm; meteorological element change;radar;terrain |
