BEIJING -- China's national observatory on Thursday renewed the blue alert for rainstorms as incessant downpours continue to wreak havoc in vast stretches of the country.

From Thursday morning to Friday morning, heavy rain and rainstorms are expected in the regions of Yunnan, Hubei, Hunan, Anhui and Jiangxi, the National Meteorological Center said.

Some of these regions will see up to 70 mm of hourly precipitation accompanied by thunderstorms and strong winds, the center said.

The center advised local authorities to remain alert for possible flooding, landslides and mudslides and recommended halting outdoor operations in hazardous areas.

China has a four-tier color-coded weather warning system, with red representing the most severe, followed by orange, yellow and blue, and the center has issued rainstorm alerts for 31 days in a row.

Since June, continuous downpours have lashed large parts of southern China, and the waters of many rivers in the affected regions exceeded warning levels.

China's Ministry of Water Resources has called for all-out efforts to prevent floods and has dispatched teams to affected areas to facilitate flood prevention and control.