Thirty-three people have been confirmed dead and 18 are still missing after Beijing's heaviest rains on record, officials said Wednesday.

China's capital has been hit by record downpours in recent weeks, damaging infrastructure and deluging swathes of the city's suburbs and surrounding areas.

Officials said Wednesday that 33 had died in the recent bad weather in Beijing, mainly by flooding and buildings collapsing, almost three times the figure given by officials last Tuesday.

"I would like to express my deep condolences to those who died in the line of duty and the unfortunate victims," Xia Linmao, Beijing's vice-mayor, told a press conference, according to state broadcaster CCTV.

Scores have died in the floods across northern China, with Beijing on Friday saying 147 deaths or disappearances last month were caused by natural disasters.

Of those, 142 were caused by flooding or geological disasters, China's Ministry of Emergency Management said.

In Hebei province, which neighbours Beijing, 15 were reported to have died and 22 were missing.

And in northeastern Jilin, 14 died and one person was reported missing on Sunday.

Further north in Heilongjiang, state media reported dozens of rivers saw water levels rise above "warning markers" in recent days.

"I still feel scared when I recall the recent flooding," Zheng Xiaokang, a police officer from the province's Jiangxi village, told the state-run Xinhua News Agency.

"In the face of the persistent downpour and rising river water, the consequences would have been devastating had we not managed to timely evacuate the villagers," Zheng said.

Millions of people have been hit by extreme weather events and prolonged heatwaves around the globe in recent weeks, events that scientists say are being exacerbated by climate change.