China should be prepared for flash floods along the middle and lower parts of the Yangtze River basin after a prolonged drought had previously dried the area out, meteorological experts warned Friday.

There is a great possibility of flash floods in the area, said Lin Jian, chief weatherman with the National Meteorological Center (NMC).

The NMC on Friday forecasted that parts of China's southwestern provinces of Guangxi and Guizhou, as well as the lower and middle parts of the Yangtze River basin would experience heavy rains in the next 24 hours.

The NMC has issued a blue rainstorm alert, the lightest in the country's 4-level rainstorm alert system.

Parts of Hubei, Jiangxi and Hunan provinces will see downpours on Friday and Saturday, with 150 millimeters of precipitation in some regions, said the NMC.

Previous storms have triggered floods in Hunan, Guizhou and Jiangxi provinces which could cause waterlogging if the heavy rain continues, said Lin.

Persistent downpours have caused floods in Guizhou over the past few days, which have killed 21 people and left 32 missing, forcing nearly 100,000 people to evacuate.

Lin attributed the sudden shift between drought and downpours to an interruption of the moonson.

Chen Zhenlin, an official with the China Meteorological Administration said local governments should take precautionary measures to shore up river banks and reservoirs to lessen the risk of floods or landslides.

Mao Liuxi, an agricultural meteorology expert with the NMC, said the flooding is not likely to have a negative impact on China's grain production. Expected high temperatures in the south later this year would ensure normal production, he added.