In which month does the cold wave usually appear?

With the passage of time, the weather is getting colder and colder. The arrival of the cold wave leads to the rapid cooling in some parts of China, and the appearance of the cold wave is also regular. So what month does the cold wave usually appear? Where does the cold wave mainly occur? Many friends want to know the answer to this question. Let's have a quick look.

In which month does the cold wave usually appear?

The occurrence time of cold wave is generally165438+1the end of October and 65438+1the beginning of October. Cold wave is a kind of disastrous weather in winter, and people are used to calling it cold wave. China's meteorological department stipulates that after cold air passes through a certain area, the temperature will drop by more than 8℃ within 24 hours, and the minimum temperature will drop below 4℃. Or the temperature drops 10℃ or above within 48 hours, and the minimum temperature drops below 4℃. Due to China's vast territory, great differences in climate between the north and the south, different lifestyles of people in different places, and great differences in the impact of the cold wave on the economy and society, the criteria for defining cold wave weather in different regions are also different. According to the China Cold Wave Yearbook, at least 32 stations in the north and at least 13 stations in the south meet the cold wave standard, or more than 40 stations in the country meet the cold wave standard, and the number of main stations with the temperature always decreasing more than 7℃ and the absolute value of negative anomaly greater than 3℃ exceeds 90, which is the national cold wave.

Where does the cold wave mainly occur?

It mainly occurs in the northeast and northwest of China, because this area is close to the cold wave source and is strongly affected by the cold wave. Cold wave is the rapid invasion of strong cold air, which will cause a wide range of severe cooling phenomenon, accompanied by strong winds, rain, snow and freezing, causing disasters. The cold wave invading China is mainly the cold high pressure that broke out in the Arctic, Russia, Siberia and Mongolia. Most of these areas are located in the Arctic. In winter, there is no sunshine for a long time, and there is snow and ice everywhere. The air mass left in these areas seems to be located in a huge natural ice bank, becoming colder and drier. When this cold air accumulates to a certain extent and the air pressure rises far above the south, it is like a flood piling up on a mountain. Whenever there is an opportunity, it will flood into the lower air pressure in the south, forming a cold wave. The formation of cold wave is usually mainly caused by cold high pressure erupting southward in the Arctic, Siberia, Russia and Mongolia. Most of these areas are located in the Arctic. In winter, there is no sunshine for a long time, and there is snow and ice everywhere. The remaining air quality in these areas is getting drier and drier. When this cold air accumulates to a certain extent, the air pressure increases to a much higher level than that in the south, just like a flood piled up on a mountain. Whenever there is an opportunity, it will flood into the south, where the air pressure is low and a cold wave will form.

The temperature will plummet in most parts of the country.

The Central Meteorological Observatory106: 00 on October 5, and the yellow warning of cold wave will be issued continuously106: 00 on October 5118, there will be a gale cooling weather process from northwest to southeast in China: the temperature in northwest, most of Inner Mongolia and most of North China will drop by 8℃ ~/kloc. Accompanied by 4 ~ 6 northerly winds, gusts 7 ~ 8; On the morning of the 8th, the lowest temperature 0℃ line is located in the area from central Shandong and central Henan to northern Sichuan, and the lowest temperature in northern South China will drop to about 10℃. It is estimated that the temperature in eastern and southern Xinjiang, most of Inner Mongolia, northern Qinghai, Gansu, Ningxia, Shaanxi, North China and most of Northeast China will drop by 8℃ ~ 10℃ from 08: 00 on the 5th to 08: 00 on the 7th, with the drop in most of Inner Mongolia, Gansu, western Shaanxi and parts of North China reaching12℃ ~/kloc-. It is accompanied by northerly winds with grades 4-6 and gusts 7-8.

What are the hazards of the cold wave?

When the cold wave comes, there will usually be windy weather, mostly in the north and northeast of China, usually above level 5. The appearance of cold wave and windy weather will have a certain impact on people's travel. At the same time, windy weather is easy to cause colds and blow down surrounding buildings. Therefore, for the sake of safety, it is not recommended to go out in windy weather. Cold wave will bring snowy weather. If it snows heavily, the road will be blocked, and then the telephone poles may be crushed, resulting in power failure. Therefore, we must do a good job in prevention and deal with the inconvenience caused by heavy snow in time.