The South China Sea summer monsoon is expected to break out around the 20th, and it is preliminarily judged that there are five large-scale precipitation processes in Guangdong during the "Dragon Boat Water" this year
Yangcheng Evening News reporter Liang Yitao Guo Siqi Correspondent Yue Ying Xuan Sui Ying Xuan Liang Qiaoqian Hao Qiannan
This year's first "Dragon Boat Water" hit Guangdong on the 19th. According to the recent monitoring by the meteorological departments of Guangdong Province and Guangzhou City, the South China Sea summer monsoon that triggered the "Dragon Boat Water" phenomenon may break out before or after May 20. It was initially determined that there were five large-scale precipitation processes during the "Dragon Boat Water" period in Guangdong this year, with high disaster risk. From 19th to 20th, Guangdong ushered in a new round of heavy rainfall. The provincial defense headquarters issued a notice requiring all local departments to do a solid job in preventing heavy rainfall during the "Dragon Boat Water" period to ensure the safety of people's lives and property. The meteorological department of Guangdong Province reminded residents all over the country to prevent continuous heavy rainfall.
This year's "Dragon Boat Water"
Slightly heavy rainfall
The onset of the South China Sea summer monsoon refers to the phenomenon that the wind direction in the South China Sea suddenly changes to warm and humid southwest wind in a large range in May every year. The South China Sea summer monsoon will carry a large amount of water vapor into South China and condense into rain in the terrain of Guangdong, which is low in the south and high in the north; At this time, although the northern cold air force weakened, it was still able to reach South China, and the cold air met the South China Sea summer monsoon to form frontal precipitation. The above weather phenomenon led to concentrated precipitation in South China around the Dragon Boat Festival, which is popularly known as "Dragon Boat Water". For the convenience of statistics, the meteorological department usually counts the precipitation from May 21 to June 20 as "Dragon Boat Water".
According to the recent monitoring by the Guangzhou Meteorological Department, the South China Sea summer monsoon in 2024 is expected to break out from the end of the fourth to the beginning of the fifth month in May (around May 20), with the onset time approaching the normal year (the fourth month in May) or slightly later.
The meteorological department of Guangdong Province predicted that during the "Dragon Boat Water" period this year, the overall rainfall in Guangdong was slightly heavier, with the provincial average rainfall of about 350 mm (325.2 mm throughout the year, 514.5 mm in 2022); The spatial distribution of precipitation varies greatly, with one to two percent less precipitation in eastern Guangdong, nearly or slightly less precipitation in southwestern Guangdong, and about ten percent more precipitation in most of the rest. It is estimated that the main precipitation period in Guangdong will be from May 19 to 21, May 25 to 27, May 29 to June 1, June 8 to 12, and June 16 to 18 before and after the "Dragon Boat Water" statistical period.
According to the local prediction of Guangzhou, the weather department of Guangzhou City, the intensity of the South China Sea summer monsoon this year is weaker than usual; However, in combination with the favorable moisture and heat conditions brought by the monsoon advancement, the average rainfall of Guangzhou during the "Dragon Boat Water" period will be more than 30% to 30% more than the same period of the year, when the average accumulated rainfall of the city will be 400-500mm.
Make a new round
Heavy rainfall prevention
According to the monitoring and forecast of the meteorological department, there were heavy rain to heavy rain and local heavy rain in western Guangdong, the Pearl River Delta and eastern Guangdong from 19th to 20th, and heavy rain to heavy rain and local heavy rain in northern Guangdong; The local area is accompanied by short-term heavy rainfall, thunderstorms and gales of about magnitude 8 and other severe convective weather. It is estimated that the risk of floods, mountain torrents, geological disasters and urban and rural waterlogging in small and medium-sized rivers in Guangdong Province is relatively high.
According to the Emergency Plan for Flood Control, Drought Control, Wind Control and Frost Prevention of Guangdong Province and the relevant regulations of the Provincial General Administration of Flood Control, the Provincial General Administration of Flood Control decided to launch the flood control level IV emergency response at 12:00 on May 18. The provincial defense headquarters requires all local departments to strengthen consultation, research and judgment, timely launch emergency response, implement various defense measures, and spare no effort to ensure the safety of people's lives and property, and minimize disaster losses.
The Three Prevention Offices of Guangzhou said that after the onset of the South China Sea summer monsoon, the precipitation in Guangzhou had the characteristics of strong local rain, and it was even possible to exceed the rain intensity in April. The maximum hourly rain intensity of the rainstorm from 19 to 20 could reach about 80 mm. At present, the soil water content in Guangzhou is still high. It is predicted that the areas with high risk of geological disasters in this round of rainstorm are: Conghua Aotou Huadu Huashan, Conghua Hot Spring Zengcheng Paitan, Panyu Dafu Mountain, Nansha Huangshan Lu and other places. In this process, the local rainfall is strong, and the predicted areas with high risk of urban waterlogging are: urban area, Panyu Nancun, Luopu, Dashi, Shiqiao, Nansha Hengli, Dongchong, Nansha Street, Huadu Xinhua Street, etc.
Editor: Nie Yue