乌鲁木齐机场春季东南大风的多资料天气过程及风切变分析

Analysis of Multi-Data Weather Process and Wind Shear of Southeast Gale in Springat Urumqi Airport

摘要: 本文利用FNL 1˚ * 1˚再分析数据、EC-thin数值预报、激光雷达数据、机场周边气象站、机场AWOS等资料对乌鲁木齐机场2022年4月18日~19日春季天气背景下的一次东南大风天气过程及低空风切变特征进行分析，结论如下：此次东南风长时间维持的原因为：1) 本次东南大风以锋前减压加回流型为主。2) 新疆脊区发展导致冷空气从脊前补充南下，使得东疆至甘肃一带冷槽维持；脊区东升导致高压南压，高压主体稳定在西藏青海一带并明显加强，地面逐渐形成东高西低、南高北低的气压形势场。北疆地区受低压系统和其前部减压影响，更有利于维持东高西低的气压场形势。3) 达坂城站与乌鲁木齐机场的气压场与机场风速的相关性较好。4) 在东南风持续期间，R07与MID端有明显的风速差，其风切变值超过安全阈值。5) EC-thin数值预报对此东南风的预报时长误差较大，预报风场的风速明显比实况偏大。6) 激光雷达风廓线资料700~1200米高度及500米高度的东南风层资料对本场东南风预报有一定的参考价值。

Abstract: In this paper, using the 1˚ * 1˚ FNL reanalysis data, EC-THIN numerical forecast, laser radar data, weather stations around the airport, and AWOS data to analyze the weathering process of a southeast wind and low-level wind shear characteristics under the background of spring weather of Urumqi airport from April 18 to 19, 2022. The conclusions follow: the reason why the southeasterly wind maintained for a long time: 1) The southeast gale was mainly prefrontal decompression and reflux type. 2) The development of the Xinjiang ridge area leads to the cold air moving southward from the front of the ridge and maintaining the cold trough from eastern Xinjiang to Gansu; The eastward rise of the ridge leads to the southward pressure of the high pressure, and the main of the high pressure is stable in Tibet and Qinghai and strengthened obviously. The surface gradually forms a pressure field with high pressure in the east and low pressure in the west, high-pressure in the south and low-pressure in the north. Under the influence of the low-pressure system and its front decompression, the northern Xinjiang area is more conducive to maintaining the high-pressure field in the east and the low-pressure field in the west. 3) The pressure field of Dabancheng Station and Urumqi Airport has a good correlation with the airport wind speed. 4) During the duration of the southeast gale, there is an obvious wind speed difference between R07 and MID, and the wind shear value exceeds the safety threshold. 5) The time error of the EC-THIN numerical forecast is relatively large, and the wind speed of the predicted wind field is obviously larger than the real wind. 6) The laser radar wind profile data of 700~1200 m height and the southeast wind layer data of 500 m height have certain reference values for the southeast gale forecast.