What is the foggy weather phenomenon?

The conditions for fog formation are cooling, humidification and concretion.

When the relative humidity reaches 100%, the water vapor in the air will condense into fine water droplets suspended in the air, which will reduce the visibility on the ground. This weather phenomenon is called fog. Most of them appear between February and April in spring.

The duration of fog is mainly related to the humidity of the local climate: generally speaking, the short fog in arid areas dissipates within 1 hour, while the long fog in humid areas is the most common and lasts for about 6 hours.

Extended data

The temperature is higher during the day, so the air can hold more water vapor. But at night, the temperature drops and the capacity of 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 makes the ground temperature drop sharply, so that the water vapor in the air near the ground can easily reach saturation in the middle of the night, condense into small drops and form fog. In autumn, winter and spring, when the temperature is lowest in the morning, the fog is thickest.

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