内蒙古中部2次高架雷暴的特征分析

Analysis of the Characteristics of Two Overhead Thunderstorms in Central Inner Mongolia

分析我国内蒙古中部地区2021年11月5日和2022年3月11日半夜至次日凌晨发生的2次“高架雷暴”时空分布、垂直热力特征等。结果表明:高架雷暴均出现在后半夜至早晨;700h Pa高度附近有强盛西南气流输送暖湿空气,使该高度层附近增温、增湿显著,存在明显湿层,假相当位温明显增加;逆温层顶之上存在对流性不稳定能量;平衡高度的温度在-20℃以下;对流触发机制是对流性不稳定层中的槽线,而不是逆温层中槽线或切变线。

This paper analyzed the spatial and temporal distribution and vertical thermal characteristics of the two“overhead thunderstorms”in the central Inner Mongolia on November 5,2021 and from midnight to early morning of March 11,2022.The results showed that all overhead thunderstorms occur from late midnight to early morning.The strong southwest air flow transported warm and humid air near altitude 700 hPa,which made the temperature and humidity increase significantly near this altitude.There was an obvious wet layer,and the pseudo phase equivalent temperature increases significantly;Convective unstable energy existed above the top of inversion layer;The temperature at the equilibrium height was below -20℃.The convective triggering mechanism was the trough line in the convective instability layer,not the trough line or shear line in the inversion layer.