There were two tornadoes in Jixi, Heilongjiang in 1 month. How do tornadoes form?

The formation of tornadoes is generally due to atmospheric instability, resulting in strong updraft, which is further strengthened due to the influence of the maximum transit airflow in the rapids. Due to the interaction with the wind direction with shear speed and direction in the vertical direction, the updraft begins to rotate in the middle troposphere, forming a mesoscale cyclone. With the development of mesoscale cyclone and its upward extension to the ground, it becomes thinner and its cooperation is strengthened, that is, the nascent tornado forms the same over-shaped tornado core as the cyclone generated inside the cyclone. The rotation in the core of a tornado is different from that in a cyclone, and its intensity is enough to make the tornado extend all the way to the ground. When the developing vortex reaches the ground level, the ground air pressure drops sharply and the ground wind speed rises sharply, forming a tornado.

Tornado is a vortex phenomenon in the atmosphere, and the wind power can reach more than 12. Although it didn't last long, it did great damage to some buildings and trees, and the weather forecast was difficult to predict. Generally speaking, tornadoes mostly occur in the south of our country.

Because tornadoes come quickly and are not easy to predict, we must respond quickly when tornadoes come. If we are in the house when the tornado comes and can't go out quickly, we should open the windows in the house immediately to reduce the damage to the house caused by the tornado, and don't be particularly close to the doors, external walls and windows. Find a hard wall or hide under a table to protect your head.

Relatively speaking, if there is a basement at home, it is safer to hide in the basement than in the house. On the other hand, if we are outside and encounter a tornado, we can lie on the ground with our heads in our arms, or we can choose a lower place to hide.

Tornadoes can only be formed when cold and warm air meet on the plain. There are mountains in the mountains, and when the wind weakens, it forms rainfall. Strong ocean warm current meets strong cold air in the north. On the plain, the east and west sides are blocked by mountains, and the low altitude of the North-South Great Plain forms a vortex of airflow, which is the easiest to form a tornado.

Because of the low airflow of strong cyclone, the harvesting effect on the ground is obvious, and there is no mountain block, which will form a strip of tens of kilometers, which will involve all the sand and vegetation on the ground and the seawater on the sea surface, forming the effect of carrying and moving. Destroy farmland and crops and take away livestock. Make people die and lose their homes. Roads have also been destroyed, and the destructive power is amazing.