Since April, most of the southern part of the country has experienced frequent rainfall, and in the past three days, many places in southern China have also suffered record-breaking rainfall, and the second flood of this year occurred in the Beijiang River in the Pearl River Basin. In the coming week (April 23-30), heavy rainfall will continue in many places in Jiangnan and South China, with localized or current heavy rainfall, and the rainfall area is highly overlapping with the previous period.
Why has it rained so heavily in the south recently? Which places need to be vigilant against disasters caused by continuous heavy rainfall?
How much rain has it been in the south lately?
In the past three days (from 8 a.m. on April 19 to 7 a.m. on April 22), the rain in the south mainly occurred in the northern and central eastern parts of Guangxi, Guangdong, southwestern Fujian, southern Hunan, southern Jiangxi and other places, and the cumulative precipitation in many places in northern Guangdong reached 200 to 300 mm. Among them, the daily precipitation in Shenzhen, Conghua, Fogang, Shaoguan, Lianzhou and other places in Guangdong exceeded the local single-day precipitation extreme value in April.
Not only in the past two days, but since the end of March, many places in the south have suffered extreme precipitation, especially in southern China, with a cumulative precipitation of more than 750 mm in Shaoguan, Guangdong. According to the statistics of the National Meteorological Information Center, from 20 o'clock on March 31 to 20 o'clock on April 21, among the national meteorological stations in the mainland, a total of 231 stations broke the record of April, 94 stations broke the record of April, and 2 stations even broke the local historical record.
What are the effects of heavy rainfall on the region?
Affected by the continuous heavy rainfall, many rivers such as the Hejiang River and the Beijiang River in Guangdong, and the Guijiang River and its tributaries in Guangxi have experienced super-alert floods. According to the Ministry of Water Resources, at 20:45 on April 20, the flow rate of the Shijiao Hydrological Station on the main stream of the Beijiang River in Guangdong rose to 12,000 cubic meters per second, according to the Ministry of Water Resources's "Regulations on the Numbering of Major River Floods in the Country", numbered as "Beijiang Flood No. 2 in 2024". As of 16:00 on April 21, a total of 24 rivers and 38 hydrological stations in Guangdong exceeded the alert water level. Heavy rainfall in South China will continue in the near future, and catastrophic flooding will occur in the Beijiang River in the Pearl River Basin.
The continuous heavy rainfall has also adversely affected production, life, transportation and travel.
On the 20th, a landslide occurred in Zhaoping, Guangxi, and Hezhou, Wuzhou and other places suffered different degrees of waterlogging.
On the 21st, many places in Guangdong issued notices of class suspension and scenic spot closure, and there was a small delay at Guangzhou Baiyun Airport.
Why is the rain so intense?
What is the reason for the recent heavy rainfall in the south?
Hu Xiao, chief meteorological analyst of China Weather Network, said that since the pre-flood season in South China this year, the subtropical high has been strong, continuously delivering abundant water vapor to South China, and the cold air from the north has continued to penetrate southward, confronting the warm and humid airflow, which has triggered continuous heavy rainfall and strong convective weather. At the same time, with the development of low vortex shear, the abundant water vapor continuously transported and the favorable dynamic lifting conditions can easily form a "train effect" in South China after the convection is stimulated, resulting in a long duration of local rainfall and a continuous superposition of the impact effect.
Which areas need to be particularly vigilant for disasters?
The Central Meteorological Observatory predicts that in late April, most parts of the south will still have a lot of rainfall, and the southern part of the Yangtze River and the central and northern parts of South China will experience continuous heavy rainfall, and the cumulative precipitation will be more than twice that of the same period in normal years.
Wang Weiyue, a meteorological analyst at China Weather Network, introduced: From the 22nd to the 23rd, the core area of rainfall in the south mainly appeared in the coastal area from Guangdong to Fujian, and there will generally be moderate to heavy rain, heavy rain in some areas, and local heavy rain.
During the day on the 24th, the rainfall in the above areas will weaken significantly, but a new round of precipitation will start again at night as the water vapor transport intensifies.
From the 24th to the 26th, moderate to heavy rain will occur in Jiangnan, South China and Guizhou, with localized heavy rain or heavy rain, accompanied by strong convective weather. Wang Weiyue introduced that the 25th will be the strongest rainfall period in this round of process, and the central and northern parts of Guangdong may encounter heavy rainfall.
The rain in the south will weaken briefly around the 27th, but from the 28th to the 30th, as the southern branch trough moves eastward, the water vapor conditions will improve again, and moderate to heavy rain will occur in Jianghan, western Jianghuai, Jiangnan, South China and Guizhou, accompanied by strong convective weather.
"Overall, at least in the next ten days, the rain in Jiangnan and South China will not stop, and the rainfall areas in many places are superimposed, and the risk of disasters is high. Wang Weiyue said that in the central and northern parts of Guangdong, northeast Guangxi, western Fujian and other places, it is necessary to strengthen the prevention of secondary disasters such as flash floods, debris flows, landslides, and urban and rural waterlogging that may be caused by continuous heavy rainfall, and the Beijiang, Dongjiang, Hejiang and Guijiang rivers in the Pearl River basin need to be vigilant against floods in small and medium-sized rivers.
How to avoid heavy rainfall?
When heavy rainfall hits, the road surface is slippery and visibility is reduced, so it is advisable for the public to minimize going out. If you need to go out, you should pay attention to traffic safety, and if you encounter strong wind and rain while driving, you should park your car in a safe place as soon as possible, and at the same time, evacuate the people on the car to a safe place as soon as possible, and do not wade into the water. Outdoor workers such as on duty and express delivery should do a good job of their own safety protection, and do not stay under tall buildings, billboards, temporary structures or large trees. In addition, the risk of secondary disasters such as flash floods, landslides, collapses, and debris flows in mountainous and shallow mountainous areas is extremely high, and the public should avoid going to mountainous areas, rivers, and areas with hidden geological hazards.
(Source: China Weather Network)