**Rare advance warning from the Meteorological Observatory, 16 main railway lines will be affected.
Author: Tang Jiehu
*: Phoenix.com.
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1.One of the most intense rains and snows in recent years will arrive during this year's Spring Festival travel peak. On January 28, the ** Meteorological Observatory issued a rare early mid-term warning: in early February, there will be a wide range of persistent rain, snow and freezing weather in central and eastern China; Heavy snow will fall in 10 northern provinces, and most of the middle and lower reaches of the Yangtze River and most of the south and southwest regions will be covered by rain belts; At the same time, there will be a large area of freezing rain.
2.In terms of specific forecast details, the current meteorological observatories in Europe and the United States are not the same for the rain and snow weather, and the European EC forecast believes that there will be heavy snowfall in the north, and the formation of a Jianghuai cyclone will affect the south; The GFS in the United States believes that the snowfall intensity in the north is average, but there will be severe freezing rain in the area of the two lakes. The forecasts given by China's ** meteorological observatory are more comprehensive.
3.The rain and snow weather is mainly due to the superposition of the southern branch trough and the north branch trough in the westerly wind belt, which is conducive to the stable northward movement of the southwest warm and humid airflow, and the weak cold air continues to move southward, thus bringing a wide range of rain and snow weather. Judging from the forecast area of the ** meteorological observatory, a large area of freezing rain covered as many as 16 railway trunk lines, including Beijing-Guangzhou and Beijing-Shanghai, which had a great impact.
4.Although the intensity and duration of the upcoming freezing rain are not as strong as in 2008, and the current infrastructure and coping measures are stronger than at that time, the large-scale rain and snow during the Spring Festival will undoubtedly bring a lot of uncertainty.
Last week's rain and snow in Jiangnan is still fresh in my memory: there was a heavy snowstorm or a very heavy snowstorm in Hunan, and Changsha's Yuelu Mountain turned into a snow-capped mountain.
In February, a round of precipitation with a larger amount of rain and snow, longer duration, wider coverage, and complex changes in the phase of rain and snow will be triggered.
The wide-ranging, long-term, high-intensity rain and snow weather will become the strongest rain and snow weather in recent years! It is the peak of the Spring Festival, which is expected to have a serious impact on the traffic conditions in the central region of China.
Due to the clear trend and the direct impact on the Spring Festival, at 16 pm on Sunday, January 28, the usually conservative ** Meteorological Observatory issued a rare early mid-term warning: in early February, there will be a wide range of persistent rain, snow and freezing weather in central and eastern China.
Heavy snow or blizzards will occur in 10 northern provinces. Among them, the cumulative snowfall in Henan, Shandong, Hubei and other places is extreme. The five provinces of Henan, Hubei, Anhui, Hunan and Guizhou in the south will have freezing rain, and the rain south of the Yangtze River will not be weak, accompanied by thunder and lightning.
The specific time period is from January 31 (week.
3. 21st of the year) and lasts until February 5 (next week.
1. Year 26), the whole process is up to 6 days. The rain and snow lasted the longest since this winter and affected the most widely.
Since the rain and snow impact period coincides with the Spring Festival travel return period, and the severely affected areas of rain and snow happen to cover the central transportation hub provinces, which is very unfavorable to traffic travel, important weather reminders for the next 3 9 days were issued in advance on the weekend.
The rain and snow process covered most of China, and in terms of specific forecasts, the cumulative snowfall in northern Shandong, southern Hebei, southern Shanxi, central and western Henan, and western Hubei is 20 30 mm, which can be converted into 15 20 cm of snow.
From central Hubei to southern Henan, eastern Henan, southwestern Shandong, central Shandong and eastern Liaodong, the cumulative snowfall will exceed 30 mm, which is equivalent to the level of blizzard, and the snow cover can reach more than 25 cm.
Among them, heavy snowstorms or extremely heavy snowfalls may form in local areas, with a cumulative snowfall of more than 50 mm, close to or more than the historical record for the same period, and can reach the level of extremely heavy snowfall in a single day, which is extreme. There is a risk of snow overwhelming agricultural and livestock facilities and simple structures.
As for the rest of North China, the central and southern parts of Northeast China and the eastern part of the Northwest to the north and west of the heavy snowfall belt, it is a cumulative snowfall of 5 20 mm, which is equivalent to heavy snowfall. (The above is a 6-day cumulative forecast, and cannot be directly applied to a 24-hour snowfall level.) But it's really going to be pretty big).
In the south, moderate to heavy rain fell to 50 100 millimetres in the middle and lower reaches of the Yangtze River and most areas south of it, and may even be accompanied by a wide range of thunder and lightning events. The southwest region is also covered by a rain belt, with a cumulative rainfall of about 10 25 mm.
Among them, heavy rainfall is expected in some areas such as the Anhui River, the junction of Hunan-Jiangxi and Hubei, and northern Guangxi, with a cumulative rainfall of more than 100 mm, and it is expected to be 120 180 mm, which is 2 6 times more than the same period in normal years.
But the real trouble is the area between the snowfall and the rainfall zone: from eastern Lu, southern Lunan, northern Anhui, eastern Henan, southern Henan to central Hubei, western Hunan, eastern Guizhou and other places, this long area will be an area with mixed rain and snow phases.
Depending on the temperature, Jiaodong should be sleet or snow; However, from eastern Guizhou, western Hunan to central Hubei and even eastern Henan and northern Anhui, due to the vertical distribution of temperature, freezing rain is very likely. And because of the heavy rainfall, there will be a lot of trouble.
Fortunately, after the 6th, except for the southern part of Jiangnan, southern China and the eastern part of southwest China, the weather in most areas north of Jiangnan and north of Jiangnan turned clear. The temperature in most parts of the central and eastern regions will drop by 4 8 and can welcome the Spring Festival.
This round of rain and snow weather process has the characteristics of wide coverage, long duration, large range of freezing rain, and extreme cumulative precipitation in some areas. Rain and snow will be frequent in the next 10 days, and the temperature in the snowfall area will be slightly lower.
Especially during the return period before the Spring Festival, rain, snow and freezing weather will have a great impact on roads, railways, aviation, etc., and all localities need to make various emergency preparations in advance to strengthen the management of traffic operation and urban safety;
The forecast of this process is long (the next 3 9 days), the current is only the overall situation forecast, the specific situation will be adjusted later, the public needs to pay close attention to the latest weather forecast, reasonable arrangements for traffic travel plans, safe travel.
The details remain controversial
According to meteorological experts, the rain and snow weather is mainly due to the superposition of the southern branch trough and the north branch trough, which is conducive to the stable northward movement of the southwest warm and humid airflow, bringing a wide range of rain and snow weather. What is this?
The southern branch trough is an important system affecting the winter weather in southern China, and its full name is the south branch trough of the westerly wind belt. In winter, the subtropical high weakens and retreats southward, and the westerly belt system also controls the mid-latitudes with the southward movement, but it is divided into two branches in the north and south due to the large terrain barrier when passing through the Qinghai-Tibet Plateau.
When the path is pushed southward to the Bay of Bengal, it will absorb a large amount of water vapor and then enter Yunnan, South China and Jiangnan regions. In this way, the southern branch trough replaces the role of the summer southwest monsoon and continues to transport water vapor to the south.
When the southern branch trough is abnormally stable, the southwest warm and humid airflow is very strong, and if it encounters cold air of appropriate intensity, cold and warm air will meet and precipitation will be formed. Since mid-to-late January this year, the power of the southern branch trough has not been weak, and it is still strengthening.
The northern branch trough, which bypasses the Qinghai-Tibet Plateau and takes the northwest path, is related to the southward movement of the cold wave. Another key to the continuation of winter rain and snow is that the cold air is neither strong nor weak. Because the strong cold wave will directly push away all the warm and humid air currents, the precipitation will not last long.
The relatively weak cold air moves southward in batches and confronts the warm and humid airflow from the southwest to form precipitation, which is easy to cause a wide range of continuous heavy rain and snow. The current situation of atmospheric circulation is conducive to this.
Due to the continuous influence of the warm and humid airflow from the southwest and the moderate intensity of cold air, the trend of widespread rain and snow in early February has been determined, but the details are still full of controversy. Taking the international European EC and the American GFS automatic numerical forecast, the prediction of the future is still quite different.
The European EC forecast has consistently overestimated the intensity of the warm and humid airflow in the southern branch trough, and believes that there will be widespread heavy snowfall in the northern region, including Beijing-Tianjin-Hebei, and there will be heavy to heavy rain in the southern part of the Yangtze River. It is even predicted that on February 4 and 5, a Jianghuai cyclone will develop eastward.
The Jianghuai cyclone is a kind of extratropical cyclone, which roughly means that the cold air from the north moves southward and strongly intersects with the strong southwest warm and humid airflow, thus "rubbing" a cyclone in the Jianghuai area.
The cyclone shifted eastward, forming strong winds and heavy precipitation, affecting the Huanghuai-Jianghuai region. That's why it's called "JAC Cyclone". It then continues eastward into the sea, affecting South Korea, and sometimes northward to affect the Tohoku region, before weakening and disappearing.
It is not easy to generate a Jianghuai cyclone in winter, because it is closely related to the intensity of the warm and humid airflow from the southwest. Cyclones occur more frequently in spring and early summer, and the highest occurrence month is April, at the turn of spring and summer in the south. At this time, the warm and humid airflow is not affected by the subtropical high and is vigorous.
According to the European EC forecast, the southwest jet stream will have a wind speed of up to 35 meters per second (equivalent to a force 12 wind) at an altitude of 3,000 meters, and 126 kilometers per hour, which is four times the usual strength, which is extremely strong. It will rub out a cyclone and bring a wide range of blizzards to the blizzard.
However, the US GFS has always overestimated the intensity of the cold wave, believing that the warm and humid airflow will be suppressed by the cold wave and retreat southward. Therefore, the snowfall intensity in the north is average, but it will create strong freezing rain in the area of the two lakes, especially in Xiangxi. After the freezing rain is over, there will be another heavy snowfall in Hunan on the 8th.
As for the numerical forecasts such as the German ICON and the Canadian GEM, they are between the European EC and the American GFS, and are more EC-oriented. It is believed that the warm and humid air currents are strong, and the cold wave is also strong. There are blizzards in the north, there are also cyclones in the Jianghuai, and the freezing rain area in the south will be very large.
Germany ICON forecasts that on February 4, freezing rain will not only cover the whole province of Hunan, but also include northern Guangxi, Wuhan and Jianghan, and even the central Anhui region around Hefei. Severe freezing rain will have a significant impact on transportation and power systems, and it will also have a much greater impact on agriculture than snow.
Now it seems that several automatic numerical forecasts feel quite outrageous. In the end, which forecast is accurate? Perhaps it is a compromise between the families, that is, the content of the important weather reminder artificially issued by the China Meteorological Observatory on January 28.
Specific impact processes
The exact details are still to be determined, but many people need certainty in their spring schedules. Based on the forecasts of all parties, the specific stages of this rain and snow process should be as follows:
The first stage is from January 29 to 31 (Monday to Wednesday), when the cold air has not yet moved southward, and the warm and humid airflow prevails.
From January 29th to 30th, there was moderate to heavy rain in the southern part of Jiangnan, the western and northern parts of southern China, and heavy rain in some areas. In most cities and counties in Guangdong, fog and Huinantian tend to be obvious.
From January 31 to February 1, the south will also heat up on a large scale, and many areas will run to more than 20, and the maximum temperature in many places in South China will exceed 25.
But at the same time, this wave of rain and snow began, and Shanxi, Shaanxi, Hebei and other places took the lead in snowfall on January 31.
US GFS forecast for the 4th.
The second stage is February 1-3 (Thursday to Saturday), the cold air begins to move south, and around February 2, the cold air will advance to the south of the Yangtze River, when the maximum temperature in most parts of the north of the Huai River will be below 0, and the temperature will change from high to significantly low along the Yangtze River.
In addition, the cold air will also collide fiercely with the warm and humid airflow from the southern part of North China to the middle and lower reaches of the Yangtze River, creating a large-scale rain and snow weather process in the central and eastern regions. The snowfall line is pressed south to the Huanghuai area, while the north of the Yangtze River is sleet.
European EC forecast for the 4th.
The third phase is February 4-5 (Sunday and next Monday), which will be the peak of this round of rain and snow, especially on the 4th. The European EC forecast is that there will be a Jianghuai cyclone in northern Jiangsu and southern Lunan, bringing the most intense rain and snow, which will have a great impact.
The US GFS forecasts heavy snow in the vast area of Jianghuai from Chongqing in the west to Yancheng in the east, and freezing rain in northern Hunan. And this day is a compensatory day and you need to go to work, which will bring difficulties to urban travel.
Canada EC forecast for the 4th.
The US GFS also believes that the snowfall in Shanxi and Shaanxi is not strong but lasts for many days. Canada's GEM believes that there is a large area of snowfall in the north, whether it is northwest or north China, or even northeast and Xinjiang, and there is a large area of freezing rain in Hunan and other places, and almost the whole country is covered by rain and snow.
The forecast of China's ** Meteorological Observatory believes that the areas seriously affected by rain and snow are located in the central transportation hub provinces of China, which is very unfavorable to the Spring Festival transportation. In short, despite the fact that the details of the specific forecast are far from the same, there are hard-hit areas anyway.
After all, this is a medium-term forecast in 7 days, and there is great uncertainty about the intensity, time, and location of the cold and warm air currents. The first is the determination of the temperature near the surface, the distribution of rain and snow, and the specific location of the boundary between rain and snow.
Another is that the thickness of the vertical warm layer of the atmosphere determines the specific area where the freezing rain falls. At that time, it may be unexpected by all agencies, and no one will be able to do so. But at this stage, we should first believe in the forecast of the ** meteorological observatory adjusted by the manual experience of experts.
The level of freezing rain hazard has been increased
*According to the latest forecast of the Meteorological Observatory, freezing rain is expected to occur from eastern Guizhou, northwest Hunan, central and western Hubei to southern Henan, northern Anhui, northern Jiangsu, and southern Shandong from February 1 to 4.
This weather phenomenon is mostly seen in Guizhou, Hunan and other places, and such a large-scale and northerly freezing rain is rare, and it is also a point that needs special attention in the process of this round of rain and snow. It's a lot harder to deal with than a blizzard.
What is Freezing Rain? The simple understanding is that dripping water into ice. Due to the heavy density of cold air and its proximity to the ground, it infiltrates faster and more significantly when it moves southward, thus forming a vertical inversion layer of the atmosphere with the warm and moist airflow transported northward from above.
To the south of the snowfall zone, the surface temperature is already below 0, but the atmosphere is still above 0 at an altitude of about 1000-2000 meters above. In this way, when the rain falls to the ground, it will quickly freeze into ice, clump into lumps, and form a thick ice armor with heavy rainfall. This is freezing rain.
Freezing rain is different from snow, it is difficult to eradicate, and it is extremely harmful to transportation and power facilities, which will bring great trouble, especially in areas where there is no experience in dealing with freezing rain. Road travel will be disrupted.
Rail travel can also slip wheels and rails, and power catenary will also be affected. Even more difficult to deal with is the freezing of the power tower wires, which are overloaded and tear off and collapse. This involves not only transportation, but also the city's power supply, which will also be significantly affected or even interrupted.
Judging from the freezing rain forecast area of the ** meteorological observatory, this large-scale freezing rain area extends from the Zunyi-Kaili line in Guizhou to the northeast to Rizhao, Shandong 1,500 kilometers away, with a width of more than 250 kilometers and an area of 400,000 square kilometers.
Such a large area and long shape cover many of the most important railway lines, starting with the Luohe-Wuhan section of the Beijing-Guangzhou Railway and the Beijing-Guangzhou High-speed Railway, and the Qufu-Bengbu section of the Beijing-Shanghai Railway and the Beijing-Shanghai High-speed Railway. These are the two most important north-south arteries in China.
Superimposing the freezing rain forecast area on the railway map, from north to south and from east to west, you will also find that the following important lines are covered:
The Yanzhou-Rizhao section of the Wari Railway is an important coal-running maritime railway.
Rizhao-Lianyungang section of Qingyan Railway, Shangqiu-Lianyungang section of Lianhuo Railway and Lianhuo High-speed Railway.
Shangqiu-Huainan section of Shanghe high-speed railway, Zhoukou-Fuyang section of Zhengfu high-speed railway and Luohe-Huainan section of Luohuai railway.
Beijing-Kowloon Railway Shangqiu-Macheng Section. Lu'an-Nanyang section of Xihe Railway.
Wuhan-** section of Xiangyu Railway. Wuhan-** section of Wuxi high-speed railway.
Lu'an-Padang section of the Yangtze River Express Railway. Dengzhou-Yueyang section of Haoji Railway.
Nanyang-Wushan section of Zhengwan high-speed railway. Qianjiang-Yiyang section of the Chongqing-Xiamen Railway, Dengzhou-Huaihua section of the Zhiliu Railway.
Qianjiang-Huaihua section of the Chongqing-Huaihua Railway. Shanghai-Kunming Railway and Shanghai-Kunming High-speed Railway Lengshuijiang-Huaihua-Kaili Section.
There are 10 important east-west railways. There are 6 important railways in the north-south direction. And most of them are important trunk lines connecting the whole country, which can be said to lead the whole body.
At the same time, due to the heavy rainfall and heavy snowfall on the north side of the freezing rain area, the highways and national highways that pass through this large area will also be seriously troubled. Of course, such an incident is very undesirable.
First of all, there is still some uncertainty about this snowfall and freezing rain, and the transport and aggregation of water vapor are highly variable in various weather systems, and the forecasts of various countries are also highly divergent. In addition, the specific impact needs to be proved in practice.
However, it is certain that this large-scale heavy rain and snow process will have a serious impact on the Spring Festival transportation and travel, and both the transportation department and the public must be prepared to deal with it in the most comprehensive way. Travelers should plan their routes reasonably and try to avoid passing through these areas on 2-5 days.
Review 2008
When it comes to freezing rain disasters, the most important case is that in early 2008, it was the long-term residence of the southern branch trough, combined with the continuous southward movement of cold air from the north, that led to a rare rain, snow and ice disaster in the south, especially on the Nanling line of Guizhou-Hunan-Jiangxi.
At that time, the cold air met with the warm and moist air currents four times – the first from January 10 to 16, the second from the 18th to the 22nd, the third from the 25th to the 29th, and the fourth from the 31st to the 2nd of February. Snow or freezing rain falls in waves.
Millions of migrant workers from Guangdong Province who are eager to return to their hometowns for the Chinese New Year are targeting their hometowns – Hunan, Jiangxi, Guizhou, Chongqing, Sichuan, Hubei and Henan. At that time, it could almost only rely on a Beijing-Guangzhou railway that crossed the South Ridge.
Not only is the capacity seriously insufficient, but it is also in a semi-paralyzed state. The frozen roads are slippery, and neither the railway lines nor the road network can be navigated. As the Spring Festival (February 7) approaches, the number of people stranded at Guangzhou Railway Station has changed from 100,000, 200,000 and 300,000 to 500,000 and 800,000.
Even maintaining order and not appearing has become a big problem. In order to solve this problem, a large number of armed police were mobilized to divert passengers, mobilize de-icing and snow removal equipment to open up roads, and restore electricity, and the Ministry of Railways transferred 220 diesel locomotives and 1,800 passenger cars from the north for emergency response.
Railway workers were ordered to go to the front line to clear the snow and ice all night, and rushed through the Beijing-Guangzhou line, as well as through the Beijing-Kowloon line through Jiangxi, Sanmao line through Guangxi, Guangzhou station was able to send 700,000 passengers one after another, and the congestion that lasted for half a month was finally over.
At present, the duration and intensity of the upcoming rain and snow freezing process are far less than those of the low temperature rain and snow freezing process in southern China in early 2008. However, in 2008, only the Nanling section of the Beijing-Guangzhou Line from Shaoguan, Guangdong Province to Chenzhou, Hunan Province was involved.
The scope of the freezing rain forecast this time is extremely large, and the more than a dozen railways involving half of the country, including the middle section of the most important major corridors such as Beijing-Guangzhou, Beijing-Shanghai, Lianhuo, Shanghai-Kunming, Yanjiang, and Beijing-Kowloon, will be severely tested on transportation and power infrastructure.
The level of infrastructure is much higher now than it was in 2008, and the response tools and experience are much richer. However, we cannot hope that freezing rain disasters will not occur. You have to prepare for the worst and be prepared for the best.
For those who plan to travel and return home, it is best to keep an eye on the weather forecast and transportation system information. It is necessary to make proper arrangements according to the situation to ensure the safety and smoothness of the Spring Festival tourism returning home.