The super cold wave is coming, do you feel the intensity of this process?

First let’s talk about the steep drop in temperature. It is expected that in the next few days, my country will see a large-scale cooling from north to south, extending from central Inner Mongolia to Guangxi. The temperature drop is generally above 6 degrees, with the highest The temperature drop will even exceed 10 degrees. By then, the lowest temperature in these cooling areas will generally reach zero degrees.

Let’s talk about what a cold wave is and under what circumstances a warning message will be issued. The definition of cold wave varies in different countries, and not every drop in temperature can be called a cold wave. Ordinary drops in temperature can only be called "cold air." In our country, a cold wave is generally defined as a cold wave when the temperature drops by 8 degrees or more within 24 hours, or has dropped by more than 8 degrees, and the minimum temperature is below 4 degrees, and a blue warning will be issued. If the temperature drops by 12 degrees or more within 24 hours, or has dropped by more than 12 degrees, a cold wave yellow warning will be issued. Similarly, if the temperature drops by more than 16 degrees, a cold wave red warning will be issued.

From the definition of cold wave and early warning information registration, combined with the "cooling forecast map", we can see that although this steep drop in temperature will affect 17 provinces, autonomous regions and municipalities, these 17 provinces Only some areas in districts and cities will issue "cold wave warnings", and all of them are blue warnings of the lowest level, mainly concentrated in North and South China.

Based on my country’s cooling data over the years during this season, this cold wave is just an ordinary cold air moving southward, and is not directly related to the so-called “cold winter” concept. For example, like the recent winter of 2018, On December 4 and December 24, large-scale cold waves occurred in our country, and cold wave warnings were issued for this reason. The scope of impact even exceeded the current 17 provinces, autonomous regions and municipalities. However, there was no "cold winter" in 2018. In contrast, this year's cold wave came later than in previous years.

In addition, the concept of cold winter is mainly related to the La Ni?a phenomenon, and its scope of influence does not only include our country. Although this year’s La Ni?a phenomenon has been declared to be formed, La Ni?a is only a statistical concept and can only be said to increase The probability of cold winter, but it cannot be used as the only basis for cold winter. Moreover, the cold winter caused by La Ni?a mainly affects the central and eastern regions of my country. However, this cold wave extends from north to south, and the areas with severe temperature drops are more concentrated in the central part. Therefore, it cannot be linked to the concept of "cold winter". The two are fundamentally different. meteorological system.

In fact, at this season of the year, the cold air that affects our country is basically generated in Siberia first, and then travels south in groups and enters our country through Mongolia. If the intensity of the cold air is not high, it will basically be blocked. To the north of the Qinling Mountains, once the cold air is strong, it will cross the Qinling Mountains and affect central and southern China. This cold air is an "enhanced" cold air, but there is no need to make a fuss, because the time has already arrived. Under the influence of the earth's revolution and the ecliptic angle, the temperature in Siberia at this time has already been around minus 25 degrees. The low temperature causes the air pressure in the region to continue to rise, eventually forming a cold air mass that presses towards low latitudes.

Although this cold wave is not directly related to the "cold winter", and the intensity is even lower than in previous years, this cold wave comes relatively late and affects the south, so the southern region must strengthen the cold wave control prevention. Because when the southern region encounters a cold wave, the increase in rain and snow and the high humidity can easily cause the road to become icy and slippery. When the humid environment is accompanied by a cold wave, the body temperature will be very low, even colder than in the Northeast, so be careful to add more clothes. .