Why do local severe convective weather also occur under the control of subtropical high pressure?

The subtropical high plays an important role in the transport and balance of water vapor, heat, and energy between mid- and high-latitude regions and low-latitude regions. It is an important system of atmospheric circulation.

As far as the subtropical high pressure is concerned, the vertical movement of the atmosphere in the east and west is very different: in the east of the high pressure, the subsidence movement is particularly strong, and the downdraft changes due to adiabatic compression. warm, causing a strong sinking inversion, called a trade wind inversion. The stratification of this strong temperature inversion is very stable, inhibiting the development of vertical convection, allowing continued sunny weather, and forming a dry climate zone on the west coast of the subtropical continent.

The western part of the subtropical high is an area of ??convergent and upward movement of low-level warm and humid air, which is prone to thundershowers.

As the seasons change, the intensity and location of the subtropical high pressure belt will also undergo obvious seasonal changes. From January to July, the main body of the subtropical high pressure in the northern hemisphere shows a trend of moving north and west and increasing in intensity; from July to January, the main body of the subtropical high pressure moves south and east and weakens in intensity. This seasonal change also has distinct stages of slow change and jump change.