BEIJING -- China's top observatory on Thursday issued a blue alert for heavy rain from now to Friday, the lowest level in the country's four-tier warning system.

Heavy rain is expected to hit parts of the Northeast and Southwest China, as well as the southeastern province of Fujian, according to the National Meteorological Center (NMC).

Some areas in Jilin, Liaoning and Guizhou provinces will be hit by 250-300 mm of rainfall within 24 hours and severe convective thunderstorms.

NMC advised local governments to prepare for possible urban flooding, landslides, and mudslides caused by the heavy rain and recommended outdoor operations be halted in hazardous areas.

China also renewed a blue alert for Typhoon Soulik, which is expected to move northward at a speed of about 10 km per hour and bring gales in coastal areas of eastern provinces of Jiangsu and Shandong.

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