The fog at night indicates the weather the next day.

The fog is small and the weather is fine; The fog is thick and there is strong wind; Fog and heavy rain are fierce; The fog is small, and it will be fine the next day.

As the saying goes, it is foggy in the morning and cloudy at night. Fog and weather fog are clouds on the ground, and clouds are fog in the sky. Because clouds and fog are formed by condensation of water vapor in the air after cooling, they just appear in different positions. Clouds are floating in the sky and the ground is covered with fog. In order to see the fog accurately, we must contact the weather before the fog. As the saying goes, "sunny and foggy for a long time, foggy and sunny for a long time." "Because it is sunny for a long time, there is little water in the air. Although the temperature drops at night, there is generally no fog. If there's fog, it's something else: the warm and humid air in the place invades quietly, forming advection fog, so the weather will turn rainy in the future. On the contrary, there is a lot of water in the air after the rain. Because the clouds cover the earth with a quilt, the geothermal energy is not easy to dissipate. When the temperature drops at night, the temperature difference is not large, and fog cannot be formed. If there is heavy fog, it is a typical radiation fog, because the clouds in the sky split at night, which leads to a strong cooling on the ground and the weather will clear up. To accurately understand the sky through fog, we must look at the concentration of fog. Radiation fog is formed by condensation of water vapor in surface air, so it is relatively light. You can see the blue sky through the fog; Advection fog, on the other hand, is formed by the cold of a wide range of warm and humid air, which looks quite dense. The intensity of this fog has a lot to do with the weather. It is based on this relationship that people sum up their own experience: "The fog is small and the weather is fine; The fog is thick and there is strong wind; Fog and heavy rain are fierce; The next day it was foggy and sunny. "