Although December 2023 is only a third of the way, the weather in the central and eastern parts of my country is like a roller coaster, ushering in waves of cold air, warm waves, cold waves, rain and snow since December, especially in the past two days, a strong cold wave has moved south, triggering widespread snowfall, and it feels like winter has come exceptionally early.
A wide range of rain and snow weather has been in the south, sweeping many places in the central and eastern parts of China. **The precipitation map drawn by the meteorological observatory this morning can be seen that on the one hand, the four provinces of mountains and rivers have become the center of the blizzard, and there have even been heavy snowstorms in some areas of Shanxi, Henan, on the other hand, the rain and snow dividing line has developed southward with the cold wave, and this morning's rain and snow dividing line has broken through the Huai River into the Dabie Mountains, and Zhengzhou and the surrounding areas have more than 20 mm of snowfall, becoming the only provincial capital city that has become the center of the snowfall.
However, according to the latest news from the ** Meteorological Observatory, after the large-scale rain and snow weather from December 10th to 11th, the next wave of large-scale rain and snow weather is ready to go - from the 13th to the 15th, there will be a large-scale rain and snow weather process in the central and eastern regions, with light to moderate snow in the eastern part of Northwest China, northern North China and the central and southern parts of Northeast China, and locally heavy to heavy snowfall; There will be rain turning to sleet or snow in central and southern North China, Huanghuai and Jianghuai, light to moderate rain in central and southern Jiangnan and southern China, and heavy rain in parts of Jiangnan. Judging from the forecast, starting from December 13, a wide range of rain and snow weather will develop, and moderate to heavy snow can be reached in many places in North China.
In the widespread rain and snow from December 13 to December 15, the precipitation forecast map around December 14 shows that heavy rain and heavy snow will occur at the same time. A wide range of blizzard will appear in Shaanxi, Shanxi, Henan, Shandong, Hebei, Liaoning, and Jilin, which means that in addition to the four provinces of Shanhe continuing to be the center of the blizzard, it may also expand to many places in the northeast, and the scope of the blizzard is larger than the past round of blizzard. At the same time, the area of moderate to heavy rain will extend from the southern part of Shandong to Anhui, Jiangsu, Henan, Hubei, Chongqing, Sichuan, Hunan and other places, and some areas may also have heavy rain. With heavy rains and snowstorms or at the same time, this means that during this time, many provinces in our country may experience intense weather.
The main reason for this second rain and snow was the southward movement of the second cold wave and the northward movement of the warm and humid airflow. Cold air, which is air that is warmer than the surrounding air, usually comes from high latitudes or high altitudes. When cold air and warm and moist air currents meet, strong convection of cold and warm air masses is formed, resulting in widespread precipitation and cooling.
So, where does the cold wave come from? This brings us to the role of the Arctic vortex. The Arctic vortex refers to a large cold vortex system at high altitude in the Arctic region, which is a component of the atmospheric circulation in the polar region. Its location, intensity, and movement have a significant impact not only on the polar regions, but also on the weather at high latitudes. When the Arctic vortex is strong enough to stay in the Arctic, the mid-latitudes of the Northern Hemisphere will hardly be exposed to strong cold air. However, once the Arctic vortex weakens and there are large fluctuations in the westerly wind belt, warm air will take the opportunity to move north to seize the polar regions.
In December 2023, this is what happened. Due to the weakening of the Arctic vortex and **, strong cold air in the Siberian region and southward, especially around December 13, a sub-center of the Arctic vortex over Siberia broke south, from a relatively westerly path into China, at this time the subtropical high just strengthened, a large number of warm and humid air flow northward, and finally the cold and warm air masses met in the central and eastern parts of China, forming a strong convection of cold and warm air masses, resulting in a wide range of cooling and precipitation.
According to the forecast of the ** meteorological observatory, after the 13th, affected by the cold wave, most parts of China will have strong winds to cool down the weather, the temperature will drop significantly, and the temperature in many places in the north will be close to the lowest extreme value in the same period in history. Around the 18th, the minimum temperature from Guizhou to the north of Jiangnan will also drop below 0 degrees. As a result, under the influence of two cold waves one after another, the temperature in many places in China will also plummet and continue to be sluggish. According to the temperature anomaly forecast, the cold area in the central and eastern parts of China will be further expanded, from December 11th to December 20th, China will have a national low temperature, only Yunnan and some areas of the Qinghai-Tibet Plateau can barely maintain a high level.
Then some netizens are going to ask: It will be cold nationwide in the middle of the year, and this winter will not be a warm winter? This is not necessarily the case, because a warm winter is the difference between the average temperature during the three-month winter period and the average temperature for the same period of the year, which reflects the average trend of the three-month temperature, rather than the absolute temperature level. For example, if there are 10 days when the temperature is significantly low, but there are also 20 days when the temperature is significantly high, and the average temperature is still high for 30 days, in fact, in the past early December, a wide range of record-breaking warm waves have shown the power of warm air, and it is not surprising that there will be a big warmer in the later period.
In the context of global warming, the overall temperature in Japan is on the rise, so even if there is a cold wave, it does not necessarily mean that the winter will be lower than before. In fact, from December 2023 to February 2024, the temperature in most parts of China will be close to the same period of the year or higher, of which the temperature in the southern part of Northeast China, North China, and northern Huanghuai will be ** 1 2 degrees higher, which means that the current cold wave and cold may only be phased, and a single weather process cannot completely determine the climate trend of the whole winter, so it is necessary to further observe whether this winter will become colder.
This is not contradictory to the trend of global warming, but due to the instability of the polar vortex and the fluctuation of the westerly wind belt caused by climate warming, the cold wave has become more intense in the south, and the warm wave has become more frequent in the north. It seems that in the warmer winter, the temperature change will be like a roller coaster. Therefore, everyone should be prepared to keep warm from the cold, rain and snow, and also pay attention to the impact of climate change.
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