Is cloudy or sunny? Is it stronger in summer or winter?

Sunny day is greater than cloudy day, which means the change of atmospheric pressure caused by the change of water vapor content under the condition of constant temperature.

Winter is greater than summer, winter is dry and cold, air density is greater than summer, and water vapor content is less than summer, thus making oxygen concentration higher than summer. So the air pressure in winter is higher than that in summer; The water vapor content in the air on sunny days is much less than that on cloudy days, and the relative oxygen concentration is higher, so the air pressure is higher than that on cloudy days.