Disaster relief will continue in China's flood-hit central and eastern provinces, though the heavy rains are expected to weaken on Wednesday, authorities said.

Flooding resulting from rainstorms that began on Thursday has left dozens dead and affected millions more across Anhui, Hunan, Hubei, Guizhou and Jiangsu provinces.

In Anhui, about 713,000 people have been displaced, 29 are dead and two are missing, the provincial government's department of civil affairs said on Tuesday.

The province's emergency response for disaster relief was upgraded to the second-highest level on Monday, while Hefei, the provincial capital, upgraded its response to the highest level late in the day.

Zhang Qingjun, mayor of Hefei, warned that flooding around the city's Chaohu lake — the country's fifth largest — could be the worst to hit the area since 1991.

Provincial authorities have distributed nearly 3,500 tents and 5,200 beds, as well as quilts and clothing to flood-hit regions as disaster relief.

Weather reports show that the heavy rain, which has lasted for days, will weaken in Anhui, Hubei, Hunan and Jiangsu provinces starting on Wednesday, but the floods may still worsen in the coming week.

Anhui authorities warned that a second flood peak on the Yangtze River, which formed on Monday in neighboring Hubei province, will reach Anhui soon, causing the water level of local rivers and lakes to climb further.

The province has assigned nearly 12,000 soldiers and many more officials and volunteers to help with disaster relief so far.

Provincial education authorities began ordering all local schools to dismiss students from Tuesday, while summer courses, which were popular in the country, "should be absolutely banned", according to a statement filed on Monday.