Why are tornadoes prone to occur in Central America?

Why are there so many tornadoes in America?

The United States is known as the "hometown of tornadoes". There are 1000 to 2,000 tornadoes every year, and the intensity is high, which is mainly related to the geographical location, climate conditions and atmospheric circulation characteristics of the United States.

The United States faces the Atlantic Ocean in the east, the Pacific Ocean in the west and the Gulf of Mexico in the south. A large amount of water vapor flows from the east, west and south to the United States. Too much water vapor can easily lead to thunderstorm clouds. When thunderstorm clouds accumulate to a certain intensity, tornadoes are produced. The United States is mainly in the middle latitude, and it is often controlled by subtropical high in spring and summer. Under the control of the subtropical high, warm and humid air from the Atlantic Ocean, the Pacific Ocean and the Gulf of Mexico is continuously transported to the United States, and thunderstorm clouds are accumulating.

The area with the most tornadoes in the United States is the Midwest, and half of them occur in spring. According to the data of the National Storm Prediction Center, it is rare that such a severe tornado occurred in the central part of the United States in June 5438+065438+ 10. The high incidence of tornadoes is generally from April to June every year. Since June, a lot of warm and humid air has moved northward to Kansas, Nebraska and Iowa, and moved to Canada in July. Since then, the number of tornadoes in the United States has been greatly reduced, but there will still be tornadoes. Statistics show that about 70 people in the United States die from tornadoes every year.

Tornado is a kind of vortex: the air rotates rapidly around the axis of tornado and is attracted by the extremely low air pressure in the center of tornado. In the thin layer of air tens of meters thick near the ground, the airflow is sucked into the bottom of the vortex from all directions. Then it becomes a vortex around the axis. The wind in a tornado is always cyclonic, and the air pressure in its center can be 10% lower than that around it.

Tornadoes are the product of thunderstorms in the clouds. Specifically, a tornado is a form in which a small part of the huge energy of a thunderstorm is released in a small area. The formation of tornadoes can be divided into four stages:

(1) The instability of the atmosphere produces a strong updraft, which is further strengthened due to the influence of the maximum transit airflow in the rapids.

(2) Due to the interaction with the wind with shear speed and direction in the vertical direction, the updraft starts to rotate in the middle of the troposphere, forming a mesoscale cyclone.

(3) With the development and upward extension of mesoscale cyclone to the ground, it becomes thinner and stronger. At the same time, a small area to strengthen cooperation, that is, the primary tornado is formed inside the cyclone, and the same process of producing the cyclone forms the tornado core.

(4) The rotation in the tornado core is different from that in the cyclone, and its intensity is enough to make the tornado extend to the ground. When the developing vortex reaches the ground, the ground air pressure drops sharply and the ground wind speed rises sharply, forming a tornado.