Why do typhoons bring natural disasters such as precipitation and strong winds?

The horizontal distribution of various meteorological elements and weather phenomena in typhoon can be divided into three areas: outer cloud area (including outer cloud area and inner cloud area), cloud wall area and typhoon eye area. The vertical direction can be divided into three levels: low-altitude inflow layer (below about 1 km), high-altitude outflow layer (above about 10 km) and middle-level updraft layer (from about 1 km to 10 km) (Figure 1 typhoon structure diagram). In the lower layer around the typhoon, several spiral air currents with isobars in the typhoon area are involved in the typhoon area and converge to rise, which promotes the development of the convective cloud system and forms the outer and inner cloud areas of the typhoon. There are several spiral rain belts in the corresponding cloud system. The more spiral airflow involved in a typhoon, the faster the tangential wind speed becomes. At a certain distance from the typhoon center, the airflow no longer hovers, so a lot of wet air is forced to rise strongly, forming a towering cloud wall around the center. The top of the cumulonimbus cloud wall can be as high as 19 km, which is the cloud wall area.

In typhoon, the maximum wind speed occurs inside the cloud wall, and the maximum rainstorm occurs in the cloud wall area, so the cloud wall area is the storm area most prone to disasters. When the updraft in the cloud wall area reaches high altitude, due to the weakening of the pressure gradient, a large amount of air is forcibly thrown out, forming an outer layer, and only a small amount of air flows inward into the typhoon center and sinks, forming a clear typhoon center, which is the typhoon eye area. The radius of typhoon eye is about 10 ~ 70km, with an average of about 25km. The release and warming of latent heat in the cloud wall area and the sinking and warming of the typhoon eye area make the typhoon a warm-hearted low-pressure system.