乌鲁木齐机场1次短时雷雨大风天气特征及成因分析

Weather characteristics and cause analysis of a short-term thunderstorm gale at Urumqi Airport

文章利用FNL 0.25°×0.25°逐6 h再分析资料、加密自动气象站和机场自动观测数据及雷达数据,对2020-06-05乌鲁木齐机场雷雨大风天气特征及成因进行分析,结果表明:1)此次过程持续时间短,影响大。在雷雨大风来临前、影响过程中及影响后期,都产生了较强的跑道水平风切变,尤其前期和后期时段,对飞行危害极大。2)在西西伯利亚低涡分裂低槽东移南下背景下,低层暖湿平流积聚大量不稳定能量,形成利于强对流发生发展的不稳定层结和环流背景。机场上空对流有效位能大量累积,气层处于强烈不稳定状态,非常容易产生强对流天气。3)在大尺度强迫抬升和低层切变辐合共同作用下触发了此次雷雨大风天气,地面中尺度辐合线促使对流云团进一步发展和维持。

Based on the FNL 0.25°×0.25°reanalysis data every 6 hours,encrypted automatic weather station,airport automatic observation data and radar data,this paper analyzes the characteristics and causes of thunderstorm gale at Urumqi Airport on June 5,2020.The results show that it lasts for a short time,but has a large effect.Before the thunderstorm gale,during and at the late stage of thunderstorm gale,a strong horizontal wind shear of runway is generated,especially in the early and late periods,which is extremely harmful to flight.Under the background of the west Siberian vortex splitting trough moving southeastward,the low-level warm moist advection accumulates a large amount of unstable energy,forming the unstable stratification and circulation background favorable for the development of strong convection.A large amount of convective available potential energy is accumulated over the airport,and the atmosphere is in a strong unstable state,which is very easy to produce strong convective weather.Under the combined action of large-scale forced uplift and low-level shear convergence,this thunderstorm gale weather is triggered,and the surface mesoscale convergence line promotes the further development and maintenance of convective cloud clusters.