After weeks of pounding rains, two provinces in southern China upgraded warnings on Tuesday as floods reached record levels and rivers overflowed their banks, prompting relocation of people and work disruptions, state media reported.

Guangdong province's Shaoguan city, where average rainfall since late May has breached historical records, raised the flood alert to "Level I", the highest.

Local authorities asked residents along river banks and low-lying houses to relocate to higher ground, after floodwaters hit a 50-year high, state television reported.

The city's flood, drought and wind control headquarters said shutdown measures may be enforced at construction sites, businesses, public transportation and docks while workers unable to show up at work should not be forced to.

The water level of Guangdong's Beijiang River also rose past warning levels and beat a 1994 record.

In Jiangxi province to the northeast, authorities raised a flood "red alert" after 485,000 people in nine districts were affected, Xinhua news agency said.

Economic losses reached 470 million yuan, with 43,300 hectares of crops destroyed, Xinhua reported.

The rains in the southern provinces, expected to peak on Tuesday, were forecast to shift northward from Wednesday.

Regions north of the Yangtze River have been experiencing searing heat, pushing up power consumption the past weekend.

China's Central Meteorological Observatory continued to issue a high temperature "orange warning" for northern areas such as central and southern Hebei, most of Beijing and parts of Shandong, Tianjin and Henan. (Reuters)