Why is the air pressure higher on sunny days than on cloudy days? Sunny, direct sunlight, high temperature. Shouldn't the air pressure be very low?

If the horizontal movement of air is not considered, the high-pressure system corresponds to the descending airflow, and the low-pressure system corresponds to the ascending airflow.

The weather is fine because the air is under high pressure control, so it is not easy to rise to form clouds. So it's not because the weather is sunny that the air pressure is high, but if it is controlled by high air pressure, it will be sunny easily.

In addition, sunny days are conducive to high ground temperature and upward movement, which is also one of the conditions of cloudy and rainy days.

There is also the influence of water vapor on sunny and cloudy days.

Of course, this is the most simplified situation, and the actual situation is more complicated.