乌兰察布市2010年一次大风、寒潮天气的分析

Analysis on a Gale and Cold Wave Synoptic in Ulanqab City

运用常规气象观测资料和欧洲数值预报图,对2010年1月19—22日从西北方向入侵的强冷空气引发大面积的大风降温天气过程进行分析。结果表明:此次寒潮主要是由贝加尔湖附近的横槽内聚积一股较强的冷空气(高空500hPa冷中心强度达-45℃、地面冷高压中心强度达1060.0hPa[1])。西西伯利亚的阻塞高压与贝加尔湖高空冷槽共同作用,西北路冷空气不断向东南侵袭,乌兰察布市处于西风带控制,横槽沿西风带向东移动分裂为两股冷空气。阻塞高压前偏北冷空气不断东移南下,引发横槽转竖并向南加深。持续性降温导致强寒潮天气过程。

By using the meteorological observation data and the European numerical forecast map, the storm weather process on January 19 to 22, 2010, were analyzed for which was caused by the strong cold air from the northwest. The result showed that the strong cold air accumulated in the transverse slot near the Lake Baikal was the main reason of the cold wave （the strength of the high altitude 500 hPa central was -45℃, the strength of the surface cold high pressure center was 1060.0 hPa）. For both of the influences of West Siberia blocking high pressure and the Lake Baikal high cold trough, the northwest cold air attacked to the southeast constantly. Be- cause Ulanqab City was controlled by westerlies, the transverse slot split into two shares of cold air during the process of moving east along the westerlies. The north cold air of blocking high pressure continued moving south, causing the transverse slot to vertical and deepened southward. Continuous cooling process led to a strong cold weather.