Is the air pressure high on sunny days or cloudy days?

Generally speaking, in the same area, the air pressure in sunny days is higher than that in cloudy days, and that in winter is higher than that in summer. Atmospheric pressure is related to air density. The density of water vapor is less than that of air. On cloudy days, there is a lot of water vapor in the air, so the air pressure becomes lower.

Atmospheric pressure is the atmospheric pressure acting on the unit area, which is equal to the weight of the vertical air column extending upward to the upper limit of the unit area. Pressure is related to altitude, temperature and other conditions. Generally speaking, it decreases with the increase of height. In the horizontal direction, the atmospheric pressure difference causes air to flow.