哈密南部一次区域性强风沙天气诊断分析

Diagnostic Analysis of a Regional Strong Wind and Sand Weather in Southern Hami

摘要: 本文利用地面常规、区域加密自动站及高空观测等资料，对哈密市伊州区2023年4月18~20日一次区域性强大风、沙尘暴天气过程从天气学角度进行诊断分析，得出结论。结果表明：大风沙尘暴天气发生在有利的气候背景下，高空斜压槽及强锋区和地面冷锋是触发强风沙的重要天气系统。前期持续增温为其提供了有利的热力条件；高空急流动量下传、强气压梯度区和变压差是大风沙尘暴产生的动力条件。大风沙尘暴发生区域，对流中低层存在不稳定层结，加剧了低层辐合、高层辐散的垂直运动发展；地面气象要素的强烈变化可作为大风沙尘暴预报的重要参考依据和着眼点。数值预报产品具有一定的预报能力，但预报量级和影响时间存在偏差。

Abstract: Based on the ground routine observational data, regional encrypted automatic station observational data and upper air observation data, a regional strong wind and sandstorm weather process was diagnostic analyzed from meteorological perspective in Yizhou District of Hami from April 18~20, 2023. The results showed that the wind and dust storms occur in the favorable climate background, and the cold front on the ground is the important weather system to trigger the strong wind and sand. The continuous warming in the early stage provides favorable thermal conditions; the momentum of the upper air jet streams transmission downwards, strong pressure gradient and pressure difference are the dynamic conditions of gale dust storms. In the area where gale sandstorm occur, there is unstable stratification in the middle and low levels of convection, which intensifies the vertical movement development of low-level convergence and high-level divergence; the strong change of ground meteorological elements can be used as an important reference basis and starting point for gale sandstorm forecast. Numerical prediction products have a certain prediction ability, but there are deviations in the forecast magnitude and influence time.