At least 37 people were killed during a record 16-hour thunderstorm in south-west China that included 40,000 lightning strikes, state media said.
Rescuers had to evacuate stranded residents in Chongqing
The city of Chongqing received more than 26cm (10 inches) of rain, the most in a 24-hour period since records began more than a century ago.
Air, road and rail traffic was brought to a halt.
Storms and floods in south-west China have caused about $5 billion (£2.5 billion) worth of damage this year.
A total of 32 of the dead in Chongqing - along with 128 injured - were hit by mudslides on Tuesday.
The ministry of civil affairs said in a news release on its website: "Some famous cultural relics were damaged by the floods. The mountain city of Chongqing has become a water city."
Landslides and lightning killed five more in the neighbouring province of Sichuan.
Both places have already suffered badly from storms and floods this year and were hit by the worst drought in more than a century last summer.
Millions of people in central and southern China live on reclaimed farmland in the flood plains of rivers.