摘要
2011年8月21—22日宁夏自北向南部分地区出现了强对流天气,局部地区遭受冰雹袭击,最大冰雹直径达4.0 cm,是近40 a以来所罕见.利用常规气象资料、加密自动气象站资料和多普勒雷达资料,对这次突发性短时强对流天气的环流背景、影响系统及中小尺度系统发生发展等进行了综合分析.分析表明,本次强对流天气具有明显的中小尺度系统特征,主要影响系统为高空冷槽、低层切变线及地面中小尺度系统.500 hPa蒙古冷槽、高低空垂直风切变是强对流天气发生发展的重要条件;多普勒雷达基本反射率因子的形态、强度、移向等特征及平均径向速度场中逆风区等对强对流天气的预警至关重要.
A strong convective weather occurred from north to south in Ningxia in August 21 to 22,2011,some areas suffered from hail, diameter of the largest hailed up to 4.0 cm, which is rare in the nearly 40 years. Using conventional observation data, automatic weather station data and Doppler weather radar data, the circulation background, affect system and process development of small scale system were analyzed. Results show that the strong convective weather has features of small scale system, the main affect system are high-altitude cold trough, low-level shear line and small scale systems on surface. Mongolian cold trough at 500 hPa, high and low altitude vertical wind shear is important condition for development of strong convective weather; Form, strength and direction of Doppler radar basic reflectivity factor and adverse wind regions in average radial velocity are crucial to warning of strong convective weather.
出处
《宁夏工程技术》
CAS
2013年第4期319-324,共6页
Ningxia Engineering Technology
关键词
强对流
中小尺度
反射率因子
strong convection
small scale
reflectivity factor
