The horizontal range of typhoon is generally oval. In summer and autumn, typhoons that affect China's coastal areas are mostly more than 1000 kilometers in diameter. In such a large horizontal range, the distribution of wind directions everywhere is very regular. Because typhoon is low pressure, its center pressure is the lowest; When the air is concentrated from all around to the center of the typhoon, it will be affected by the rotation of the earth, so the wind direction should deflect an angle. This deflection results in the wind direction in the horizontal range of typhoons in the Northern Hemisphere, which always blows counterclockwise from the periphery to the center. So the wind direction in the typhoon area is different, but there is a certain wind direction in a certain place. In addition, in the typhoon area, the closer to the center of the typhoon, the denser the air is, and the wind direction there moves almost along the circumference with the center of the typhoon as the center, so the deflection angle of the wind direction pointing to the center in a counterclockwise direction (i.e., the angle between the wind direction and the circumference tangent) is also small; The farther away from the center of the typhoon, the greater the declination angle. At the same time, the closer to the typhoon center, the stronger the wind will be; The farther away from the typhoon center, the smaller the wind. So no matter where you stand in the typhoon zone, as long as you stand against the wind, the center of the typhoon must be 45~90 degrees to the left in front of you.

As we know, the wind direction and the motion direction of the typhoon are two different concepts. Typhoons are mobile. For example, most of the typhoons that affect China's coastal areas move from the southeast; When its center is on the sea surface north of the Ryukyu Islands, its northwest edge may have extended to the Shanghai area. At this time, the Shanghai area will not blow southeast wind because the typhoon moves from the east. From the distribution map of wind direction in the typhoon area, we can know that the wind is blowing northerly at this time. At this time, if you are standing facing south, the typhoon center is 45 degrees to the left in front of you, which is the southeast of China.