What are the weather systems that affect the advancement of the rain-snow dividing line?

The weather systems that affect the advancement of the rain-snow boundary mainly include the Mongolia-Siberia high pressure and cold fronts. The strong Mongolia-Siberia high pressure pushes the cold air southward, and the cold and warm air meet, forming a cold front in front of the cold air. As the cold front moves southward, it brings rain, snow and cooling weather, causing the rain-snow dividing line to continue to advance southward.

1. The Siberian High (also known as the Mongolian-Siberian High or the Asian High) mostly occurs between the autumnal equinox and the winter solstice. In winter, it is located in the large-scale high pressure (anticyclone) center in Siberia and Mongolia. It is a typical Due to the different thermal properties of land and sea, the continental air mass cools quickly in winter and the ocean cools slowly. Asia is the largest continent in the world and has an obvious continental climate. The east of Asia is adjacent to the Pacific Ocean, and the airflow flows from the Pacific Ocean to Eurasia. In Siberia A high pressure area forms in the area. The Siberian High is one of the four major seasonal atmospheric activity centers in the Northern Hemisphere. Its existence strongly affects eastern Asia, making the region's winters colder than those at the same latitude.

2. When the front moves, the cold air mass plays a leading role, pushing the front to move to the side of the warm air mass. This kind of front is called a cold front. Cold front is what everyone often refers to as the cold air front. It is the vanguard of southward cold air and is the most common weather system affecting China, especially in the winter half of the year. Every few days in winter, a stream of cold air invades the interior from northwest and north China. When a cold front passes through, it will be accompanied by an increase in northerly winds, an increase in air pressure, and a decrease in temperature. Sometimes it will cause rain and snow, and even heavy rain in summer. Generally, after the cold front passes through, the local area will be controlled by cold high pressure. The weather became sunny.