Why do areas controlled by subtropical high pressure experience hot and muggy weather, and the weather is sunny and cloudy?

Let me give you an example first. Typhoons are formed because in low pressure areas, the air pressure is low and there is less air, so the surrounding air replenishes it. Due to the Coriolis effect, the replenishing air hovers. When it enters a low-pressure area, it becomes a typhoon. Similarly, the subtropical high pressure is a high-pressure area, and the air disperses around. Cold air cannot come, and convective clouds cannot enter. Therefore, high temperature and muggy weather will occur in the area controlled by the subtropical high pressure. And the weather is sunny and cloudy.

In addition, the air moves from high places to the ground, and the conditions for the formation of rain are updrafts and condensation nuclei, but no updrafts, so there is little rain.