Why is it humid in spring?

This is a common phenomenon of returning to the south in the southern coastal areas.

Returning to Nantian is a phenomenon of warmer weather, which generally appears in February and March in spring. The main reason is that after the cold air leaves, the warm and humid airflow quickly counterattacks, resulting in an increase in temperature and air humidity. Some cold objects are easy to produce water droplets when they encounter warm and humid airflow. When Return to the South Sky appeared, the air humidity was close to saturation, and the walls and even the ground would "bubble". Everywhere is wet, and the air seems to be able to wring water out. Dense fog is the most distinctive appearance of "returning to the south sky" According to statistics, when the phenomenon of returning south is serious, the visibility can be reduced to 50 meters. In the return weather in the south, some items or food are easy to get wet, and then moldy and rotten. Therefore, appropriate moisture-proof measures should be taken.

In spring, water will come out from the walls and floors in the southern sky, which is actually very similar to the principle of sea fog.

Warm and humid ocean air flows from the warmer sea surface to the colder sea surface, and the water vapor in the air condenses into droplets, which accumulate in the air to form fog. If the temperature difference between the sea surface through which the airflow passes is large, there is a greater chance of forming fog.

Similarly, due to the cold weather in winter, the walls and floors are very cold inside and outside. If warm and humid air flows through the walls and floors at this time, the water in the air will condense into water droplets and adhere to the walls and floors, just as water seeps from the walls and floors.

In summer, even if there is humid ocean airflow, the walls and floors are not cold enough inside and outside, and the walls and floors will not get out of water.

Returning to Nantian is especially common on the island where I was born. Almost every day for a period of time, not only everywhere is wet, but also clothes and shoes are easy to get moldy. Some time ago, it was freezing in Guangzhou, and the temperature suddenly came up, which became a "tidal" state ... You can turn on the "dehumidification/dehumidification" function of the air conditioner/fan at home and open fewer doors and windows.