摘要: |
本文利用常规天气资料,物理量场资料,云图和雷达回波以及EC模式预报资料,分析了2020年4月16日8时—17日12时,葫芦岛地区出现了中雨,局部大雨的过程的成因,结果表明:受高空冷涡东移南下与低涡共同影响,我市建昌县最先开始降水,高空冷涡位于河北北部内蒙古一带,低空有低涡切变系统,低涡东南侧有偏南急流输送大量水汽北上,暖湿气流拐弯减速辐合,水汽辐合抬升,并且位于高空冷涡东南侧动力抬升区。辐合抬升结合动力抬升引发强降雨,从低空风切变,正涡度平流看,动力条件非常好,葫芦岛地区位于倒槽顶部冷暖空气交汇处,也是造成此次葫芦岛地区春季透雨的主要原因。 |
关键词: 高空冷涡,春季透雨,水汽辐合 |
DOI: |
投稿时间:2020-04-23修订日期:2020-07-15 |
基金项目: |
|
An analysis of the causes of the spring rainfall in Huludao caused by a low vortex system |
lilin,yuyawei,lizheng,zhangyuyuan |
(suizhongxianqixiangju;huludaoshiqixiangju;xingchengshiqixiangju) |
Abstract: |
Based on the conventional weather data, physical field data, cloud chart, radar echo data and EC model forecast data, this paper analyzes the causes of moderate rain and local heavy rain in Huludao area from 8:00 to 12:00 on April 16, 2020. The results show that: due to the influence of the cold vortex moving eastward and southward and the low vortex, Jianchang County of our city began to rain first, and the cold vortex is located in the Inner Mongolia area in the north of Hebei Province, There is a low-level vortex shear system, a southerly jet on the southeast side of the low-level vortex transports a large amount of water vapor northward, the warm moisture flow turns to decelerate and converge, the water vapor converges and rises, and it is located in the dynamic uplift area on the southeast side of the high-level cold vortex. The convergence uplift combined with the dynamic uplift causes heavy rainfall. From the low-level wind shear and positive vorticity advection, the dynamic conditions are very good. Huludao area is located at the intersection of warm and cold air at the top of the inverted trough, which is also the main reason for the spring rainfall in Huludao area. |
Key words: Cold vortex at high altitude, rain in spring, convergence of water vapor |