Beijing, March 15 (Reporter Zhang Ni) Recently, the rising temperature in most parts of the country made people feel the warmth of spring, and the temperature in many cities even hit a new high this year. However, from today, affected by cold air, the north will usher in a "weather change", and the temperature drop in some places may reach 20 C.
The temperature in the north "reverses the daily limit" and Jinan cools down or reaches 20 C.
Recently, the temperature in North China, Huanghuai and other places climbed to a new high this year.
According to China Weather Network, the temperatures in Beijing, Shijiazhuang, Zhengzhou and other cities all hit new highs this year, while Linzhou (30.6℃) in Henan and Shexian (30.5℃) in Hebei exceeded 30℃, making them the first two cities in northern China to reach above 30℃ this year.
On the 14th, the warmth in the north continued. The highest temperatures in Lanzhou and Xining were above 20℃, which was as warm as early May.
However, after the warmth reached its peak, the temperature in the north ushered in a "daily limit reversal".
The Central Meteorological Observatory issued a forecast on the 14th that in the next three days, the temperature in the central and eastern regions will reverse, and the temperature in the north of the middle and lower reaches of the Yangtze River will drop by 6 ~ 10℃, and the local temperature drop can reach more than 12℃. Some areas in the northwest will also be accompanied by windy and dusty weather. At present, the temperature in the south is high and the unstable energy is sufficient, so it is easy to stimulate strong convective weather when it meets cold air.
The reporter observed that there will be a "big diving" of temperature in some cities on the 15th, from spring to winter.
For example, according to the data of Jinan Meteorological Bureau, the highest temperature in Jinan reached 27℃ during the day on the 14th, and it will be only 7℃ during the day on the 15th, with a drop of 20℃.
In addition, the influence of cold air on North China, Huanghuai and other places will start from the night of 14th, and the temperature will dive sharply on 15th, and the maximum temperature will drop to around 10℃. At the same time, the arrival of cold air will obviously alleviate the low visibility weather that lasts for many days.
Data Map: On March 9, 2016, affected by strong cold air, snowfall and cooling weather occurred in many places in Gansu. The picture shows the citizens walking in the snow. Photo by Chen Fei
The temperature plummeted, and the "cold spring" came?
The attack of cold air makes people feel chilly in spring, so does it mean that the cold spring is coming?
The reporter found that the cold in late spring refers to the weather phenomenon that the temperature rises rapidly in early spring (generally refers to the end of February and the beginning of March) and the temperature is lower than normal in late spring (generally refers to April).
Long-term rainy weather or frequent cold air invasion, or strong radiation cooling on sunny nights under the control of continuous cold and high pressure, can easily cause late spring cold. The climate in early spring is changeable. If the cold air is strong, the temperature can drop below 10℃, even in rainy and snowy weather.
However, the reporter noted that although it has been more than one month in beginning of spring, many areas have not yet entered the meteorological spring.
According to the Division of Climatic Seasons, the 5-day moving average temperature based on the current year’s temperature series constitutes a moving average temperature series. When the moving average temperature series is more than 10℃ and less than 22℃ for 5 consecutive days, the first date in the corresponding current year’s temperature series that is more than 10℃ is taken as the start date of spring.
According to this standard, many parts of the country, including Beijing, have not yet officially entered the spring, so this cooling can not be called "late spring cold".
Why is the weather changeable in spring?
The recent temperature "roller coaster" has made people realize what "a child’s face changes three times a day in spring".
Why is the weather changeable in spring? In this regard, the meteorological department gave three reasons.
First, the atmospheric circulation situation has been adjusted. In spring, the high-altitude westerly circulation affecting China becomes relatively flat, the intensity of the weather system weakens, and the mobility is very obvious. Cold air, like a passer-by, meets with warm air, and jointly staged a series of rainy and snowy weather "short plays".
Second, the cold and warm air are evenly matched. In spring, the warm and humid air flow from the ocean is becoming more and more active, and at this time, the cold air is not willing to quit the weather stage. The two are frequently dispatched, and they advance and retreat with each other, staged scenes of spring thunder, rain and snow. Once the rain clears in the south, the temperature will rise again soon.
Third, solar radiation began to strengthen. After entering March, the direct point of the sun gradually moved from the south of the equator to the north hemisphere. At this time, the sunshine was stronger than that in winter, but after all, it was not so strong, which made people feel that there was still cold in the morning and evening, and the temperature rose obviously around noon.
At the same time, experts also remind the public to pay attention to "spring cover" when it is warm and cold, and adjust their clothes according to the temperature and humidity at that time. The temperature is lower in the morning and evening of spring than at noon, so it is better to wear more clothes than at noon in the morning and evening. When reducing clothes, you should reduce your coat first, then lower your clothes, and pay more attention to keeping your lower body warm. (End)