乌鲁木齐机场一次雷暴大风天气成因分析

The Analysis of the Cause of a Thunderstorm and Strong Wind Occurred at Urumqi Airport

摘要: 本文利用常规高空地面探测、新疆区域加密自动站、FY4A卫星TBB、乌鲁木齐机场多普勒天气雷达资料对2022年6月30日夜间发生于乌鲁木齐机场的一次雷暴大风天气进行研究，着重分析雷暴大风天气的环流形势、β中尺度MCS特征发展演变的卫星、雷达特征。结果表明：1) 此次雷暴大风天气是在高空西西伯利亚低涡底部偏西气流分裂的短波槽东移、高层处于西南急流出口区右侧的辐散区、低层切变线共同作用下产生的。地面温度持续升高为强对流的发生提供较好的不稳定能量和不稳定层结。2) 多个γ尺度对流云团在发展过程中合并加强生成β中尺度对流云团并逐渐东移影响机场及乌鲁木齐市区。对流发展至鼎盛时期MCS的长轴达300 km，短轴近100 km，较强的MCS中尺度系统造成沿天山一带出现雷暴大风天气。3) 雷达图中可以明显看到强回波云团在发展过程中，在其移动方向前方不断激发新的回波云团发展并加强，多个强回波云团簇合并且发展加强形成成片的强对流回波，造成大范围、长时间雷暴大风天气。4) 地面风场辐合线的存在有利于两个对流云团发展加强，促使地面风进一步加强，有较强正反馈作用。

Abstract: Using high and ground sounding data and Xinjiang Regional automatic weather station and FY4A satellite TBB and Urumqi airport doppler weather radar data to analyze the circulation pattern and development and evolution characteristics of beta MCS characteristics which accompanied with a thunderstorm and strong wind occurred at Urumqi airport On the night of June 30, 2022. The result shows that: 1) The thunderstorm and gale weather was caused by the combined action of the short wave trough splitting the west air flow at the bottom of the high-altitude West Siberian vortex, the divergence area on the right side of the southwest jet outlet area at the upper level, and the low-level shear line. The continuous rise of ground temperature provides better unstable energy and unstable stratification for the occurrence of strong convection. 2) Multiple γ Mesoscale convective cloud clusters merge and strengthen in the development process β the mesoscale convective cloud cluster gradually moved eastward to affect the airport and Urumqi city. The long axis of MCS reached 300 km and the short axis was nearly 100 km when the current developed to its peak. The strong mesoscale system of MCS caused thunderstorm and gale weather along the Tianshan Mountains. 3) In the radar field, it can be clearly shows that the severe echo cloud cluster is always developing, and new echo cloud clusters are constantly excited to develop and strengthen in front of its moving direction. Multiple echo clouds cluster merge and develop to broad of severe convective echo which resulting in large-scale and long-term thunderstorm and gale weather. 4) The existence of the convergence line of the surface wind field is conducive to the development and strengthening of the two convective cloud clusters, and promotes the further strengthening of the surface wind, which has a strong positive feedback effect.