Why is it boring before it rains in summer?

Because the air humidity is high before it rains. When it rains, the clouds are very low and cover the air like a quilt, so the heat and moisture in the air can't be emitted. In addition, summer is rich in water vapor and the air humidity is high. When the temperature is not too high, the sweat on people can't evaporate in time, and the sweat can't spread out of the body quickly, so it feels particularly sultry.

Specific reasons

Summer rainfall is generally caused by the combined influence of cold air and warm and humid airflow. The sultry weather is the expression of the increase of water vapor and temperature in the atmosphere, and it is also a precursor of summer thunderstorms. The rain in summer is mostly showers and thunderstorms, which is due to the fine weather, high temperature and strong air convection in some areas, which makes a large number of hot and humid air rise sharply and form cumulonimbus clouds.

At the same time, the hot air in the atmosphere increases and the water vapor is sufficient. The temperature doesn't change much at this time. However, because the atmosphere contains a lot of water vapor, which is saturated, it is difficult to evaporate the water on the ground.

Knowledge expansion

Every rainy day in the middle and lower reaches of the Yangtze River in China, there will be a long period of rainy and continuous temperature, at which time everything is very susceptible to damp and mildew.