Why does the weather suddenly get hot a few days before the cold air goes south in winter? What is the reason?

In winter in our country, the weather before cold air goes south belongs to warm air control weather. Without the cooling effect of cold air, the ground will be heated by solar radiation. There is a lot of water vapor and humidity near the ground, so it is difficult to dissipate the heat on the ground, and the weather will naturally heat up.

The cold air heading south in winter and spring is formed under the influence of Asian high, so it can be said that it is weather under the control of anticyclone. However, in the process of cold air going south, a cold front phenomenon was formed. Therefore, cold air heading south in winter and spring is both anticyclone weather and cold front weather. Because cold front weather is more prominent, it is customary to say that cold air in winter and spring is cold front weather.

Extended data:

The cold wave invading China mainly includes:

1. West Road: It enters Xinjiang, China from the west of Siberia and advances to the southeast via Hexi Corridor;

2. Middle Road: After entering China from central Siberia and Mongolia, it passes through Hetao area and south-central China;

3. East Road: From East Siberia or eastern Mongolia, it enters the northeast of China and goes south through North China;

4. East Road plus West Road: The cold air in East Road goes south from the lower reaches of Hetao, and the cold air in West Road goes south from the southeast of Qinghai. Two cold air often meet on the east side of the Loess Plateau, between the Yellow River and the Yangtze River, causing a wide range of rain and snow, and then the two cold air merge south, causing strong winds and obvious cooling.