Describe the weather, the beginning of a foggy morning.

Generally, there is more fog in autumn and winter morning, and it is usually very cold after fog. The temperature is higher during the day, so the air can contain more water vapor. This is the fog in the morning, and the temperature will rise after the fog. It is foggy at night, because the temperature drops and the air is quite humid. When it cools to a certain extent, some water vapor in the air will condense out and become many small water droplets suspended in the air layer near the ground, so the fog will last for a long time and the temperature will drop.

The specific knowledge is that when the air contains the largest amount of water vapor, it reaches saturation. The higher the temperature, the more water vapor is contained in the air. 1 m3 air, the maximum amount of water vapor can be 6.36g at 4℃. When the air temperature is 20℃, the maximum water vapor content in 1 m3 is17.30 g. If the water vapor content in the air is greater than the saturated water vapor at a certain temperature, excess water vapor will condense out. When enough water is combined with tiny dust particles in the air, water molecules themselves will also combine with each other and become small water droplets or ice crystals. Water vapor in the air exceeds saturation and condenses into water droplets.

If the ground heat is lost, the temperature drops, and the air is quite humid, then when it cools to a certain extent, part of the water vapor in the air will condense out and become many small water droplets suspended in the air layer near the ground. This is fog. Both it and clouds are caused by temperature drop, and fog can actually be said to be a cloud near the ground.

The temperature is higher during the day, so the air can hold more water vapor. But at night, the temperature drops and the ability to contain water vapor in the air decreases. Therefore, some water vapor will condense into fog. Especially in autumn and winter, due to the long nights, there are not many opportunities without Feng Yun, and the ground heat dissipation is faster than that in summer, which leads to a sharp drop in the ground temperature, so that the water vapor in the air near the ground can easily reach saturation and condense into small water droplets in the middle of the night and in the morning.

One of the conditions for fog formation is cooling and the other is humidification, which increases the water vapor content. This is formed by radiation cooling, which mostly occurs at night and early morning when the sun is shining, the breeze is blowing gently, and the water vapor near the ground is rich and relatively stable or there is inversion. Meteorology calls it radiation fog. The other is the fog formed by the horizontal movement of warm and humid air and the gradual cooling after passing through the cold ground or water surface, which is called advection fog in meteorology; Sometimes the fog formed by two reasons is called mixed fog. It can be seen that those conditions are late autumn and early winter, especially in the morning of late autumn and early winter.