Is it sunny or rainy when the air pressure is high

The atmospheric pressure is high on sunny days. If the air pressure drops suddenly on a sunny day, it is a precursor to rain. If it rains for several days and the air pressure becomes higher, it can be expected that the weather will clear up.

Atmospheric pressure will increase or decrease with the weather. The air pressure is different between sunny and cloudy days. So, is the air pressure high on sunny days or cloudy days? Let's get to know each other.

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The change of atmospheric pressure is related to the weather. At different times, the atmospheric pressure in the same place is not exactly the same. We know that the density of water vapor is less than that of air. When there is more water vapor in the air, the air density will become smaller and the atmospheric pressure will also decrease.

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The change of atmospheric pressure is also related to temperature. Because the air density decreases when the temperature increases, the atmospheric pressure is smaller when the temperature is high than when the temperature is low.

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The atmosphere is the whole air layer around the earth, which contains not only nitrogen, oxygen, carbon dioxide and other gases, but also water vapor and dust. We call air with less water vapor (i.e. low humidity) "dry air" and air with more water vapor (i.e. high humidity) "wet air".

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Don't think that "dry" things must be lighter than "wet" things. In fact, the molecular weight of dry air is 28.966, while the molecular weight of water vapor is 18.0 16, so dry air molecules are heavier than water vapor molecules. Under the same conditions, the density of dry air is also greater than that of water vapor, and the density of water vapor is only about 62% of that of dry air.

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Because the atmosphere is in the open space around the earth, there is no specific boundary to limit its movement range, which makes it different from the gas in a closed container. For a closed container filled with air, as long as the gas in the container is not saturated, when we input water vapor into the container, the pressure of the gas will inevitably increase, but the atmosphere will not.

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