Why do tornadoes frequently hit China cities recently？ Chief forecaster of the Central Meteorological Observatory explained

　　[Global Times Comprehensive Report] Recently, strong convective weather occurred in many places in China, and Suzhou and Wuhan were hit by tornadoes. Up to now, 12 people were killed, hundreds were injured and a large number of houses collapsed. In many people’s minds, tornadoes should be a very rare natural phenomenon. Why have the serious consequences of hurting people occurred frequently recently?

　　Zhang Tao, chief forecaster of the Central Meteorological Observatory, explained that tornado is a local, small-scale and sudden strong convective weather, and it is a strong and small-scale air vortex caused by air convection movement under extremely unstable weather conditions. The space-time scale of tornadoes is very small, the diameter is generally less than 100 meters, and the time from occurrence to dissipation is several minutes to dozens of minutes.

　　From this point of view, strong convective weather is the basic condition for tornado. At present, China has entered a period of high incidence of strong convection, and the types are complex and mixed, mainly concentrated in the middle and lower reaches of the Yangtze River. Zhang Tao said that at the beginning of this year, the severe convective weather in China was less and late, but now it has developed to a stage of more and stronger, which is exactly different from previous years. In addition to the conditions of strong convection, the strong low-level jet will greatly increase the probability of tornado. In addition, the plain area is a relatively high incidence area of tornadoes. For China, the middle and lower reaches of the Yangtze River, the Pearl River Delta, the Northeast Plain and the North China Plain are all areas where tornadoes occur frequently. Plain areas are often densely populated areas, so special attention should be paid to prevention and response.

　　At present, it is very difficult to monitor tornadoes at home and abroad, and it is difficult to directly monitor tornadoes with existing meteorological observation equipment. Because the scale of tornadoes is very small, this means that the probability of tornadoes being captured by meteorological observation stations is small, and there is almost no direct observation data. Therefore, the direct identification of tornadoes depends on witness. If there is no witness, the occurrence of tornadoes can only be indirectly determined through disaster investigation and radar telemetry data.

　　When preventing tornadoes, we should first pay attention to the early warning information of tornado background, that is, the possibility of strong convective weather; When the meteorological department issued an approaching forecast and warning minutes to hours ago, it is necessary to reduce going out and avoid strong convective weather and possible tornadoes in safe places; When faced with the threat of tornado, observe the tornado dynamics outdoors and avoid its path in time. If indoors, stay away from doors, windows and the outer walls of houses. The safest place is the basement or semi-basement. When you go out by car and encounter a tornado, you must never drive to avoid it, nor do you avoid it in the car. You should leave the car immediately and take refuge in low-lying areas. (Ma Jun)