China's national observatory on Friday issued a blue alert for a new round of rainstorms expected to hit the country's southern regions over next three days.

From Saturday to Monday, heavy rains are likely to fall in most parts of regions along the Yangtze, Hanjiang and Huaihe rivers as well as south China, the National Meteorological Center said.

Some parts in Guizhou, Hubei, Hunan, Jiangxi and Guangdong provinces, Chongqing municipality as well as Guangxi Zhuang autonomous region will also likely see heavy rains from Friday to Saturday, the center said.

Of these regions, Chongqing, Guizhou, Hunan, Hubei and Jiangxi are expected to see rainstorms, it said.

From April 5 to May 10, the country's southern regions have experienced eight rounds of heavy rainstorms, pushing up water levels of major rivers, it said.

The center urged local authorities in south China to strengthen monitoring and guard against possible geological disasters such as landslides.

Meanwhile, it forecast thunderstorms, strong winds and hail in southeastern parts of northwest China, Sichuan province and Qinghai-Tibet Plateau within the next 24 hours.

The national observatory uses a four-tier color-coded weather warning system, with red being the most severe, followed by orange, yellow and blue.