Pujiang weather network

Since June every year, the central and eastern regions of China have gradually entered a period of precipitation concentration, but this June is particularly special, with a wide range, strong intensity and heavy rainfall. This year, floods caused by rainfall in the south have affected tens of millions of people in Guangxi, Guizhou, Hunan, Sichuan and Jiangxi provinces.

Why is there so much rain in the south this year? What is the trend of the future weather situation?

Data Map: On June 13, it rained cats and dogs in Pujiang County, Jinhua City, Zhejiang Province, and the traffic police were on duty in the rain to prevent vehicles from entering the flooded section. China News Agency issued Zhang Hao Zhenshe

Endless rain

Nearly one-sixth of the country's rainfall exceeds 200 mm.

Looking back on the past June, there were five large-scale rainfall weather processes in southern China. From June 2nd to July 2nd, the Central Meteorological Observatory issued a rainstorm warning for 3 1 day.

According to the statistics of China Meteorological Bureau, it is not an exaggeration to say that the rain in the south this year is "splashing water":

The accumulated rainfall of nearly 6.5438+0.5 million square kilometers of land exceeds 200 mm;

The cumulative rainfall of 700,000 square kilometers of land exceeds 300 mm;

Rainfall with a cumulative rainfall of more than 500 mm occurs in places around 50,000 square kilometers;

Distribution of national precipitation in June. Image source: Central Meteorological Observatory

How heavy is the rain?

12 Taihu Lake falls into Hubei.

According to the analysis of the Central Meteorological Observatory, this year's flood season has three characteristics: wide coverage, heavy rainfall and strong extremes.

The heavy rainfall in the flood season this year can be seen from the data that nearly one-sixth of the country's rainfall exceeds 200 mm.

According to statistics, the national average precipitation in June reached 1 10.9mm, which was 12% higher than normal, and was the ninth highest since 196 1( 1998 was the highest in the same period in history). If ranked by province, the precipitation in Hubei is the highest in the same period of history, and Jiangsu and Heilongjiang are the second highest in the same period of history.

To what extent? Taking Hubei Province as an example, the rainfall is converted into adult accumulated water of about 53 billion cubic meters, which is equivalent to 12 Taihu Lake and 0.5 Qinghai Lake!

Water quantity comparison Image source: Central Meteorological Observatory

Among the major cities in the south (National Meteorological Station), in June, Wuhan, Hubei Province ranked first with 465,438+09mm, followed by Hangzhou, Hefei and Nanjing, with rainfall above 300mm.

"The rain is so heavy that it can't fit anywhere." On June 7, the rainfall in Yangshuo County, Guilin City, Guangxi Province reached 327.7mm, breaking the local record of the largest single-day rainfall. You know, the average annual rainfall in Beijing is only 532.8+0 mm.

How heavy is the rain?

In June, it rained most of the time in the south.

The rainfall process that started on June 2 1 day is called the strongest rainfall since the flood season this year. This round of heavy rainfall lasted for a long time and affected a wide range. Guizhou, Chongqing, Hunan, Hubei, Jiangxi, Anhui, Jiangsu, Zhejiang, Shanghai, Guangxi and other 10 provinces were locked by it.

According to the Central Meteorological Observatory, in June, the rainfall area of southern 15 provinces (autonomous regions and municipalities) was over 250 mm 165438+ 10,000 square kilometers, and the rainfall area of over 400 mm was about 276,000 square kilometers.

During the whole June, except for north-central Yunnan, half of the time in southern China was spent in rain, and the rainy days in northeastern Guangxi and western Yunnan exceeded 25 days.

According to the previous judgment of the National Climate Center, from June to August,

China's climate conditions are generally biased, with more extreme weather and climate events, and the overall spatial distribution of precipitation is "more in the north and south, less in the middle", and waterlogging is more serious than drought. In other words, there may be heavy rain in the north and south for some time to come.

On the afternoon of June 18, a sudden rainstorm occurred in Kunming, Yunnan, and citizens traveled in the rain. China News Service reporter Liu Yuyang photo

How heavy is the rain?

Precipitation in many places broke through historical extremes

Generally, from April to early June, South China is in the pre-flood season, and parts of the south of the Yangtze River are in the rainy season. By mid-June, the rain belt will go north and enter the middle and lower reaches of the Yangtze River.

He Lifu, chief forecaster of the Central Meteorological Observatory, said that from the stage characteristics, the rainfall time in the south this year is still normal, but the intensity is indeed relatively strong. Recently, in some southern provinces, such as eastern Hubei, eastern Sichuan and Chongqing, the rainfall is 2-4 times more than normal, and even 5 times more in some areas.

Since June, 4 1 national meteorological stations in southern China have exceeded the daily rainfall extreme value in June, and 5 stations in Yangshuo, Guangxi have exceeded the historical extreme value.

Such heavy rainfall caused the water levels of rivers, lakes and reservoirs in the Yangtze River basin to rise rapidly, and some rivers experienced super-warning floods and some tributaries experienced super-historical floods, resulting in serious local geological disasters.

On June 22nd, Chongqing Hydrological Monitoring Station issued a red flood warning, which was the first time since 1940 was established.

On the afternoon of June 29th, fish fled from the water accumulation point in a residential area in Hongshan District, Wuhan, and some citizens fished on the water accumulation road after the rain. Image source: people's vision

The rainstorm warning lasts for 3 1 day.

Why is there a constant rainstorm in the south this year?

In June every year, China will enter the precipitation concentration period, which also declares that China has entered the main flood season in an all-round way. Rainfall needs conditions. According to the analysis of the Central Meteorological Observatory, water vapor, ascending motion and duration are the key reasons for frequent heavy rainfall.

Hu Xiao, chief meteorologist of China Weather Network, said that the most important reason why the rainfall in flood season is so fierce, lasts for a long time and has sufficient stamina is the good water vapor conditions. For example, the plum rains entrenched in Jiangnan and Jianghuai areas are the continuous rainfall brought by sufficient water vapor.

In addition, as the "pushing hand" behind the weather in flood season in China, the intensity and location of subtropical high determine the distribution changes of rain belts in central and eastern China.

According to experts' analysis, in previous years, the subtropical high was located to the east of Taiwan Province Province, China, but this year it is obviously located to the west, closer to China and stronger. Therefore, it helped the humid air flow that affected China.

The picture shows that on June 22, Tonglu County suffered from severe rainstorm and flood, and firefighters launched rescue in the flood. Photo courtesy of Zunyi Fire Rescue Detachment

It will rain in the future.

A new round of rainstorm has arrived, and Beijing-Tianjin-Hebei will also join.

According to the latest forecast of the Central Meteorological Observatory, from July/KLOC-0 to July 3, the rain is still strong in southeastern Sichuan, central and southern Chongqing, Guizhou, Yunnan, western and southern Hubei, and central and northern Jiangnan.

Chen Tao, chief forecaster of the Central Meteorological Observatory, analyzed that the rainfall intensity of this round is large, which overlaps with the affected area of the heavy precipitation process at the end of June, and the accumulated precipitation will be more than 1 ~ 2 times than normal.

It is worth noting that North China, Huanghuai and other places have also joined the "rainfall camp". From July/KLOC-0 to July 3, North China and Huanghuai will experience a rainfall process, with moderate to heavy rain and local heavy rain in some areas of Beijing, Tianjin and Hebei, accompanied by strong convective weather such as thunderstorms or hail.

On the 30 th, the mountain road in the township of Wucheng District was flooded.

Critical period of flood control!

There may be a regional flood.

On June 29, the Ministry of Water Resources held a video conference to analyze and judge the rain and water conditions and arrange the deployment of defense work. The meeting mentioned that it is expected to be rainy in the north and south during the main flood season, and regional floods may occur in the Yangtze River, Yellow River, Haihe River, Pearl River, Songhua River, Liaohe River and other basins, and local heavy rains and flash floods may occur frequently, which will put great pressure on reservoir safety and the flood control situation is not optimistic.

Wang, deputy director of the Department of Flood and Drought Disaster Prevention of the Ministry of Water Resources, said on June 30 that July and August are the key periods for flood control in China, and river floods show a trend of frequent occurrence, which needs to be highly concerned.

"This year's flood has four characteristics-there are many heavy precipitation processes, many rivers with excessive police, concentrated floods and high river water levels." Liu Zhiyu, deputy director of the Hydrology and Water Resources Monitoring and Forecasting Center of the Ministry of Water Resources, said.

Wang introduced that since the beginning of this year, heavy rains and floods have occurred frequently in China, with many processes and a large amount of water. Since June, the main control stations of Xijiang River, Beijiang River, Upper Yellow River, Taihu Lake and other rivers and lakes in the Pearl River Basin have experienced floods exceeding the warning water level (flow), and some small and medium-sized rivers have experienced frequent floods, and regional storms and floods are more serious than normal.

Since the beginning of June, there have been 250 rivers that have been flooded by the police, accounting for 92% of all the rivers that have been flooded by the police, mainly in Guangdong, Guangxi, Guizhou, Hunan, Hubei, Jiangxi, Sichuan, Chongqing, Anhui and other provinces and cities. (End)