The floods affected China's Qinghai province, while millions of people in the southwest suffered a crushing heatwave.
Sixteen people have died and 36 others are missing after flash flooding hit northwest China.
A search and rescue operation has been launched, the provincial emergency management department said in a statement on Thursday, without providing more details.
The floods occurred in a mountainous region of Datong county in Qinghai province.
The deluge comes during a summer of extreme weather in China, with multiple cities recording their hottest days.
Why are rain-triggered floods becoming more intense and more frequent around the world? pic.twitter.com/kju9iOyY4f— TRT World (@trtworld) July 31, 2022
Heatwaves and floods
Four people were killed and nine others injured in a flash flood in southwest China on Saturday, local authorities said.
And severe flooding in southern China in June displaced more than half a million people and caused an estimated $250 million in damage.
Meanwhile, millions of people in southwest China are facing rolling power cuts this week as a crushing heatwave led to an electricity supply crunch that has forced factories to halt work.
Scientists say extreme weather across the world has become more frequent due to climate change, and will likely grow more intense as global temperatures rise.