Since ancient times, there has been a Xi of "counting nine" among the people of the mainland, and from the winter solstice, every nine days is counted as one "nine", and yesterday (January 9) was the first day of "three nine". It is said that "Sanjiu is cold", and often "Sanjiu Day" is the coldest season in the north.
However, according to the forecast, during this year's "March Nine" period, the temperature in most parts of the mainland will be higher than that of the same period in normal years, and the warmth in many places in the south will even be comparable to that of normal March. However, in the later period of "March Nine", there may be a wide range of rain and snow weather processes in the central and eastern regions.
▲Source: Central Meteorological Observatory
The temperature in most parts of the mainland was high during the "March Nine" period
The south is as warm as March
According to meteorological analysts, during this year's "March 9" period (January 9 to 17), the cold air affecting the mainland is more frequent, but the forces are relatively weak, and the impact is northerly, and most parts of the country basically show a trend of rising temperatures. Among them, around the 14th, the maximum temperature in many places in the middle and lower reaches of the Yangtze River will break through 20 °C, which is as warm as normal March.
Judging from the temperature trend in various places, from the 11th to the 14th, the maximum temperature of 10 °C line will be rapidly raised northward, from the Yangtze River all the way north across the Yellow River to the south of North China, when the temperature in the north of the Yangtze River will be high in a large area, Gansu, Ningxia, Inner Mongolia, Shaanxi, Shanxi, Henan Some places The maximum temperature may be close to or break the highest record in the same period in history.
Why is the "39" season the coldest?
According to the average temperature statistics of the past 30 years, nearly eighty percent of the regions on the mainland have the lowest temperature in the "39" and "49". Among them, most of the northern regions entered the coldest time of the year in "March 9".
▲ Source: Calle Pictures. Photo by Ning Ying
This is because, during the winter solstice, there is still "residual heat" on the earth. During the winter solstice, the sun's rays hit the Tropic of Capricorn directly, and the solar altitude angle in the Northern Hemisphere is the smallest, making the winter solstice the shortest day and the longest night in the Northern Hemisphere. At this time, the surface of the northern hemisphere, where the continent is located, receives weak solar radiation energy, so the temperature is low. After the winter solstice, although the solar altitude angle begins to gradually increase and the length of the daylight gradually increases, the daily heat loss from the surface is greater than the solar radiation received. This kind of energy will continue until the "39" and "49", when the heat budget on the surface is close to balance, and the overall "accumulated heat" on the surface is the least, and for many places on the mainland, the lowest temperature of the year usually occurs at this time.
However, the continent is vast, and the climate varies significantly from region to region, and the coldest periods are not exactly the same in different regions. The eastern part of the Yangtze River and most of South China are colder in the "49th". Yunnan, southeastern Tibet and other places may enter the coldest period of the year after the winter solstice. In places such as the southeast coast of the mainland and Hainan Island, the lowest temperature may occur on "May 9".
Rain and snow in the late "39" period
There will be widespread precipitation in the central and eastern regions
According to meteorological analysts, starting from January 15, with the strengthening of the southern branch trough, the bottom water vapor conditions will improve, and the central and eastern parts of the mainland will welcome a wide range of rain and snow weather processes.
According to the forecast of the Central Meteorological Observatory, from the 15th to the 17th, there will be light to moderate snow or snow showers in the eastern part of Northwest China, southwestern North China, and northern Huanghuai, and light to moderate rain from southern Huanghuai to northern Jiangnan, with locally heavy rain.
▲Source: Central Meteorological Observatory
In the latter part of this year's "March Nineth", a wide range of rain and snow weather hit the mainland, and all localities should pay attention to preventing the adverse effects of slippery roads and reduced visibility on transportation.
On the "39" day, pay attention to these things
As the saying goes, "cold in Sanjiu", cold not only brings physical discomfort, but also brings pressure to the cardiovascular system.
According to the survey, there are obvious seasonal changes in the incidence of cardiovascular diseases in the mainland, especially in the cold winter, the incidence of coronary heart disease, stroke and other diseases will increase significantly!
▲ Source: Picture Worm Creativity
In the cold winter wax moon, sometimes an inadvertent action may make the blood vessels "collapse instantly", so everyone must be careful. To protect blood vessels, do 3 actions less:
- Action 1: Get up too violently
6~10 o'clock in the morning is the "danger period" of blood pressure, and about 40% of myocardial infarction and 29% of sudden cardiac death occur at this time.
If you wake up abruptly, it is likely to cause a sudden increase in blood pressure, which can easily lead to an acute attack of cardiovascular disease.
Suggestion: After waking up in the morning, give yourself about 5 minutes to "lie in bed", stretch your waist first, wake up and nap, and then get up slowly.
- Action 2: Frequent entry and exit of the heating room
In winter, the outdoor temperature is low, and the indoor air conditioner and heating are usually turned on, and the temperature difference between indoor and outdoor is large.
If you go in and out frequently in a short period of time, it is easy to catch a cold, and it is easy to cause vasospasm, which increases the risk of cardiovascular accidents.
- Action 3: Turn your head sharply
For the elderly, especially those with arteriosclerosis, the fast and large movements of turning back and turning around are likely to induce vascular dissection, cerebral infarction and other diseases, especially in winter.
Source: Xiaokang Toutiao WeChat public account comprehensive CCTV news client, People's Daily, Central Meteorological Observatory, Hebei weather, @中国天气
Editor-in-charge: Tian Yuanhuaying
Proofreading: Zhou Jingtao
Review: Wang Fang