BEIJING, June 20 (Xinhua) -- China's national observatory on Saturday renewed a blue alert for rainstorms across vast stretches of the country for the next 24 hours.

From Saturday morning to Sunday morning, heavy rain and rainstorms are expected in the provinces of Sichuan, Guizhou, Hunan, Hubei, Henan, Jiangxi, Anhui, Zhejiang, Yunnan, Heilongjiang, Tibet Autonomous Region and Chongqing Municipality, the National Meteorological Center said.

Some of these regions will see up to 60 mm of hourly precipitation, the center said.

China has a four-tier color-coded weather warning system, with red representing the most severe, followed by orange, yellow and blue.

Local governments should remain alert for possible flooding, landslides and mudslides caused by heavy rain, and outdoor operations should be halted in hazardous areas, the center said.