"The north wind blows, the snowflakes are fluttering …", with the strongest cold wave coming in the second half of the year, this lyric can be said to be gradually becoming realistic. And the most personal feeling of us, especially our friends in the north, is probably "cold is a word". One by one, they were "frozen into dogs" and fully realized the "sour and refreshing" of "cold heart and flying heart".
So, how "frozen" is this cold wave? Where did it come from? How should we "deal with" it?
Double warning of cold wave and blizzard, local cooling is over 16℃!
The Central Meteorological Observatory issued a yellow warning of cold wave at 06: 00 on the 20th and upgraded it to an orange warning on the 21st!
The Central Meteorological Observatory issued a blue warning of blizzard at 06: 00 on the 20th!
The China Meteorological Bureau launched a three-level emergency response to major meteorological disasters (cold waves) at 09: 00 on the 20th!
Judging from the actions of the meteorological department, this cold wave cannot be underestimated. So how fierce is it?
The local temperature drop will exceed 16℃. The cold wave weather process mainly takes place on the 20th to 24th, and there will be strong winds and cooling weather in most areas in the central and eastern regions, and the average temperature will generally drop by 6 ~ 10℃, among which the temperature in southeastern North China, central and western Huanghuai, central and western Jianghuai, Jianghan, most of the south of the Yangtze River, northern South China, eastern Sichuan, eastern Chongqing and central and eastern Guizhou will drop by 12 ~ 14℃, and in southern Henan, western Anhui, central and northern Hubei and central and western Hunan.
Temperatures in many places hit a new low since winter. The cold wave weather will cause the lowest temperature in many places in China since the winter of this year, and some areas may break the historical record. In the early morning of 24th, the lowest temperature in the northern part of North China Plain will reach -10℃, and the lowest temperature 0℃ line will be located in the northern part of Jiangnan, and the lowest temperature in the southern part of Jiangnan and northern part of South China will reach 4 ~ 8℃! At that time, the southern friends who are still showing short sleeves recently should also wear long pants (even wool pants and cotton pants)!
There is heavy snow in the north and heavy precipitation in the south. Since yesterday, North China has experienced a wide range of rain and snow, and Beijing, Tianjin and other places have ushered in snow at the beginning of this winter. Meteorological monitoring shows that the precipitation in the Beijing-Tianjin-Hebei region, western Liaoning and south-central Inner Mongolia is 2-9 mm, with snowstorms in northern Hebei and western Liaoning. With the continuous "going" of cold air to the south, affected by it and warm and humid airflow, North China, Huanghuai, central and southern Shaanxi, Jianghan Jianghuai and other places may usher in the first snow of this winter in this round. Today and tomorrow, there will be moderate to heavy snow and local snowstorms in southwestern Shaanxi, western Huanghuai, northern Jianghan and northwestern Jianghuai.
Beijing may welcome the coldest week in 30 years. Affected by strong cold air, the minimum temperature in Beijing will drop by 8 ~ 10℃ from 21st to 23rd, and it will drop to about -10℃ in the plain and -14℃ in the mountainous area. It is estimated that the highest temperature on Tuesday and Wednesday this week is only -2℃, and the last time such a low temperature occurred, it was -3.3℃ on November 28, 1987. The lowest temperature on Wednesday is expected to drop to -10℃, the lowest since -10.6℃ on November 29th, 1987.
In addition, it should be pointed out that in addition to low temperature, rain and snow, the above-mentioned cooling areas are accompanied by northerly winds of 4-6 grades, and the winds in the eastern and southern sea areas are 7-9 grades. Strong low temperature, coupled with rain (snow) water and strong wind as "accomplices", the somatosensory temperature will be even colder, and the kind of "sour" will make you tremble!
Where does the cold wave of "Crying You Frozen" come from?
When it comes to where the cold wave comes from, there must be many friends who come with their mouths open: Siberia! Because in everyone’s impression, cold air seems to come from there. For example, in the weather forecast, it is often heard that "a cold air front from Siberia arrived in northern Xinjiang this morning …". As the highest level of cold air, cold wave is no exception.
This answer is right, but it is not accurate enough. To put it simply, when Wan Li comes to China not far from the cold wave, he usually passes through three "old nests", a "gas station" and four "ordinary roads".
The so-called three "old nests" are actually the three main sources of cold air: the first is on the southeast side of Iceland, the second is on the west side of Xindi Island, and the third is on the east side of Xindi Island. These three sources are all at high latitudes, and they are often oblique to or rarely seen by sunlight all the year round. The ground receives less heat from sunlight and the temperature is very low. For example, the temperature in the Arctic Ocean is often below -20℃ in winter, and the lowest can reach-60 ~-70℃. The average temperature in January is often below -40℃, which can be said to be a "production base" with good cold air.
Among the three cold air sources, 95% of the cold air passes through the central part of Siberia, where it is accumulated and strengthened. It can be said that it is an important "gas station" for cold air to go south, and it is therefore called the "cold wave key area". Therefore, the cold in Siberia can be imagined. The winter is cold and long, mostly at-20 ~-45℃, and the average annual temperature is lower than 0℃. Oymyakon, the "cold pole" in the northern hemisphere, is located here. Just three days before the cold wave arrived in China, many places in Siberia had dropped below -40℃.
After the "transit" in Siberia, there are four main ways to come to China: the first path is called the West Road, and the cold air enters Xinjiang in the direction from west to east, and then goes south along the Hexi Corridor and the east side of the Qinghai-Tibet Plateau; The second path is called Northwest Road (also called Middle Road), and the main cold air passes through central Mongolia to the south of Hetao area in China, directly to the middle and lower reaches of the Yangtze River and South China; The third path is called East Road, where cold air moves to northeast and north China through eastern Mongolia, and then spreads south from the lower reaches of the Yellow River. The fourth route is called East Road and West Road. The cold air in East Road goes south from the lower reaches of the Yellow River, and the cold air in West Road goes south from the eastern part of Qinghai. Two cold air streams join forces with the Yangtze River in the south of the Yellow River, and then break out to the south, affecting Jiangnan and South China. The intensity and weather conditions caused by cold waves in different paths are very different. Specific to the cold wave process, the "main force" of its cold air mainly comes from the northwest road.
Bonus skills: what should I do in the face of the "high cold" cold wave?
1. When the temperature drops suddenly, it is necessary to add clothes to keep warm in time, especially to keep hands and face warm to avoid frostbite.
2. Beware of the strong wind brought by the cold wave, reinforce the structures that are easily blown by the strong wind, such as doors and windows, coamings, scaffolding and temporary structures, and properly arrange outdoor items that are easily affected by the strong wind.
3. When using coal stoves for heating (mostly in rural areas or some old residential areas), attention should be paid to keeping the room ventilated, so as to ensure that the furnace smoke is correctly discharged outdoors without leaking indoors, and to prevent carbon monoxide poisoning.
4. Avoid walking on the ice to prevent the road from slipping and falling; Try to avoid driving on roads, overpasses and bridges covered with snow and ice.
5. Old and weak patients, especially people who are sensitive to temperature changes such as cardiovascular patients and asthma, should try not to go out.
6. Pay attention to rest, don’t be overtired, and let your body have enough energy to keep warm.
The article was produced by China, a popular science student, and was authorized to be published in the column "Learning Science with Xiaobian" of CCTV. Please indicate the source for reprinting.
Production: weather intelligence team
Producer: computer network information center
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