Guangxi began to defend against typhoon Ⅳ.
Affected by high trough, low-altitude shear line and weak cold air on the ground, there will be a heavy rainfall process in Guangxi. It is accompanied by strong convective weather processes such as 8 ~ 10 thunderstorm and strong wind. The precipitation in northern Guangxi will reach 50 ~ 150 mm, and some areas will exceed 250 mm. The upper reaches of Liujiang River and some tributaries such as Longjiang River, Guyi River, Luoqinghe River, Gui Jiang River and Hongshui River may be flooded. There may be a flood near the warning water level of Liujiang River. Mountain torrent disaster refers to river floods, mudslides and landslides caused by rainfall in hilly areas, which cause losses to the national economy and people's lives and property.
Guangxi is located in the subtropical monsoon climate zone and is often affected by typhoons in summer and autumn. There are many rocks and mountains in the mountains, and the drainage is not smooth, which leads to flooding. The flood control facilities of major rivers in Guangxi are in good condition, such as Baise water control project, Yongjiang levee and Xijiang water control project. At the beginning of the flood season every year, Guangxi will be hit by several rounds of heavy rainfall. One of the important reasons is the large rainfall and wide range. Gao Anning, chief engineer of Guangxi Meteorological Observatory, said that the rainfall in 95 townships exceeded 400 mm in this round of rainfall, including 8 17 mm in Luojin Town, Yongfu County, Guilin City, 13 hours 6 18 mm.
Due to the difference of land and sea distribution, the boundary layer heating area is easy to trigger the mesoscale weather system, which leads to frequent rainstorms. Affected by topography, the time and intensity of rainstorm in Guangxi are different. The upper reaches of Liujiang and Gui Jiang are located in the high precipitation area in northern Guangxi. Although the reach above Liucheng County in Rongjiang River and Guilin City in Gui Jiang have fallen below the warning water level, the flood peak in the upper reaches is advancing towards the mainstream of Xijiang River, while the reach below Yangshuo County in Gui Jiang, the middle and lower reaches of Liujiang River and Xijiang River still exceed the warning water level, and the flood control situation in Guangxi is still not optimistic.