Why was the temperature very hot before it rained, but it cooled down after it rained?

The temperature will be lower after the rain. The degree of reduction is related to the difference of air humidity before and after rain. The greater the humidity difference, the more obvious the temperature drop.

The reason for this is the following：

First, water can absorb heat. Water can store heat. When water (raindrops) comes into contact with the air, the heat in the air can be transferred to the water, making the temperature of the water rise and the temperature of the air drop.

Second, evaporation of water can take away a lot of heat. The heat of vaporization of water is 40.8 kJ/mol, which is equivalent to 2.260 kJ/g. Water will evaporate in the air, and when it evaporates, it will absorb a lot of heat from the environment, and the temperature of water vapor will not rise, which is the same as the water temperature before evaporation. Because raindrops can only absorb heat in the air when they evaporate, the temperature usually drops a lot after rain.

The former reason is not the main reason, but the latter reason is the main reason.

Extended data:

The air in summer is very humid, and there is a lot of water in the air. At night, the atmosphere is easy to gather and condense without being heated by the radiation of the sun; Thereby forming a larger and thicker cloud mass, so it is easier to rain at night.

There are many reasons for the rain, and the manifestations are also unique, such as Mao Mao rain, continuous rain, pouring rain and so on. After the water on the earth is irradiated by sunlight, it becomes steam and is evaporated into the air. Water vapor condenses into small water droplets when it meets cold air at high altitude. These water droplets are very small, with a diameter of only 0.0 1 ~ 0.02 mm and a maximum of only 0.2 mm. ..

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