Study on thunderstorm characteristics over the capital international airport of diurnal and spatial distribution and moving under different weather situations

Using sounding and radar data at the capital airport from 2008 to 2014 (except for 2010), the diurnal and spatial distribution and moving characteristics of thunderstorms happened over the capital international airport were studied. The results show as follows. Firstly, the multicell thunderstorms come mainly from the west and northwest mountain areas, while single-cell thunderstorms were generated in the plains. Meanwhile, the number of multicell thunderstorms moving from northwest to southeast is the same as that of thunderstorms moving from southwest to northeast. Most single-cell thunderstorms move from southwest to northeast. Both average moving speed of multicell and single-cell thunderstorms are 43 km/h. But the multicell thunderstorms which move from northwest to southeast are the fastest (45 km/h) among all multicell thunderstorms. The average speed of the single-cell thunderstorms moving from west to east are the fastest (57m/h). Except that the average speed of the multicell thunderstorms moving from southwest to northeast is the same as that of single-cell thunderstorms, the moving speed of those from other directions are faster than that of multicell thunderstorms. The main period of the mountain area thunderstorms, which mainly move from northwest to southeast, is 03-13UTC, with the peak value appearing around the early evening (11UTC). The maximum peaks of thunderstorms that concentrate on two slope areas are 07UTC (15BT) and 10UTC (18BT), respectively. The thunderstorms generated on the southwest slope all move from southwest to northeast, while the thunderstorms on the northwest slope mainly move from northwest to southeast. The plain thunderstorms mainly occur during 07-13UTC, with the peak appearing at 09UTC. The thunderstorms on the foot of the mountain move from west to east, while the others move from southwest to northeast.Secondly, after classing different situations, it is found that the thunderstorms which are triggered by westerly trough and low vortex mostly move from southwest to northeast, but the thunderstorms which are triggered by northwest airflow and cross trough mainly move from northwest to southeast. The westerly trough and transverse trough thunderstorms occur mostly on the plains, and move from southwest to northeast. The northwest airflow thunderstorms mostly occur in the mountains, and move from northwest or west to the southeast. The number of thunderstorms that are triggered by low vortex generate in the mountains and the plains are the same, but the thunderstorms from the mountains move from northwest to southeast, and the thunderstorms generated in the south plain move from southwest to northeast. Among the thunderstorms that move from southwest to northeast, the vortex thunderstorms move the fastest (55 km/h), followed by the northwest airflow type(44 km/h), and the slowest type is westerly trough (39 km/h). Among the thunderstorms moving from northwest to southeast, the westerly trough and transverse trough type move the fastest (50 km/ h), followed by the northwest air flow type (42 km/h), and the vortex type (41 km/h) moves the slowest. Among all westerly trough type thunderstorms, the thunderstorms moving from northwest to southeast are the fastest. Among the northwest airflow type thunderstorm, the average speed of the thunderstorms moving from southwest to northeast and from northwest to southeast are similar, while the average speed of the thunderstorm triggered by the vortex moving from southwest to northeast is faster than those from other directions.