A new round of precipitation is coming to the south! Beware of the "overlay effect" when traveling on May Day

It is the May Day holiday, but the weather is not peaceful. Starting from May 3, a new round of heavy rainfall will occur in southern my country, which will have a great impact on people's transportation.

01 What are the main areas and time periods affected by this round of heavy rainfall?

It is expected that during the daytime from May 3 to 5, heavy to torrential rain will occur from west to east in the central and eastern Guizhou, southern Jianghan, Jianghuai, Jiangnan, and southern China. Among them, parts of southeastern Hunan, central and southern Jiangxi, northeastern Guangxi, and central and northern Guangdong will experience torrential rain , accompanied by local strong convective weather such as thunderstorms, gales, or hail.

The cumulative rainfall in the above-mentioned areas is 40 to 80 mm, 100 to 180 mm in parts of southeastern Hunan, central and southern Jiangxi, northeastern Guangxi, central and northern Guangdong, etc., and up to 200 to 250 mm in some local areas; the maximum hourly rainfall in the above-mentioned areas is 30 to 50 mm, and up to more than 70 mm in some local areas.

In addition, there will be strong convective weather such as thunderstorms, gales or hail of levels 8 to 10 in Guizhou, central and eastern Guangxi, and central and western Guangdong.

On the 3rd, the heavy rainfall mainly affected eastern Guizhou, central and northern Hunan, eastern Guangxi, western Guangdong and other places; on the 4th, the heavy rainfall area moved eastward, mainly affecting southern Hunan, Jiangxi, northern Guangdong and other places; on the 5th, it mainly affected Guangdong and western Fujian, western Zhejiang and other places.

In addition, from the 5th to the 6th, the cyclone that enters the sea will continue to move northward and affect the Northeast region. Liaoning, central and eastern Jilin, southeastern Heilongjiang and other places will also have moderate to heavy rain and local heavy rain.

02 What are the characteristics of this round of heavy rainfall? Why has it rained so frequently in the south recently?

This round of heavy rainfall has the characteristics of wide impact area, strong local rainfall and storm weather. The heavy rainfall area overlaps with the previous rainfall area, so the disaster risk is relatively high .

Why is there so much rainfall in the south recently?

The plateau trough and southern branch system that have recently affected the southern region are active, and the water vapor supply from the South China Sea and the Bay of Bengal is abundant, resulting in frequent precipitation processes in the southern region and more precipitation days than the same period of previous years. At the same time, the temperature in the southern region is higher than the same period of previous years, and the atmospheric water content is rich and the unstable energy is high, which makes the convection develop vigorously and the rainfall intensity is large.

Meteorological monitoring shows that in April this year, there were continuous heavy rainfall processes in South China and Jiangnan. The cumulative rainfall in Hunan, Jiangxi, Zhejiang, Fujian, Guangdong, and eastern Guangxi exceeded 250 mm, and some areas in southern Jiangxi and central and eastern Guangdong reached 600 to 800 mm, and local areas in northern Guangdong reached 1,000 to 1,498 mm. According to statistics from the Guangdong Meteorological Department, the average rainfall in Guangdong Province in April was 497.4 mm, breaking the historical record of rainfall in April . The rainfall in Shaoguan, Heyuan, Huizhou, Meizhou, Guangzhou and other places was 3 to 4 times higher than the same period of previous years.

03 How will precipitation develop in the future?

After the heavy rainfall from the 3rd to the 5th, the rainfall in southern China will be generally weaker from the 6th to the 10th compared with the previous period, but there will still be a lot of rainfall in Guangxi, Guangdong, Guizhou, southern Hunan and other places, with heavy rain or rainstorms in some areas. The public still needs to remain vigilant and pay attention to the latest weather forecast. It is the May Day holiday, and while enjoying the holiday, the public also needs to pay special attention to the impact of this round of heavy rainfall on travel.

The public needs to strengthen prevention against disasters such as rainstorms and floods, and be alert to the lag in the occurrence of geological disasters . Before traveling, be sure to pay attention to the relevant warning information issued by the local meteorological department, plan your trip in advance, reduce going out during heavy rainfall, and avoid staying in low-lying areas such as mountain streams and rivers. At the same time, pay attention to rain and lightning protection, and guard against the risks of secondary disasters such as mountain torrents, landslides, and mud-rock flows.

04High temperatures in many places , many places in Northeast China experience advanced warmth

During the May Day holiday, high temperatures were recorded in many places. In the coming days, the temperature in the north will rise. The highest temperature in many places in the northeast will reach around 25℃ , which will be significantly warmer than the same period of previous years. The highest temperatures in Harbin, Changchun and Shenyang will all rise to above 25℃.

From the 5th to the 7th, the temperature in the northwest region will also rise significantly. The highest temperature in Urumqi on the 5th will hit 31°C, crossing into summer in one click.

However, due to the influence of rain and cloudy weather in other parts of South China and most parts of Jiangnan, the temperature will be lower than the same period in previous years. During the May Day holiday, the highest temperature in Hangzhou, Shanghai and other places is basically just over 20℃. The public going out needs to pay attention to the latest forecast and add or remove clothes in time.

Comprehensive sources: Central Meteorological Bureau, China Weather Network, CCTV 1, etc.