The heavy rain follows Tropical Storm Kajiki, which made landfall in central Vietnam Monday afternoon. The storm weakened into a tropical depression on Tuesday.
At least eight deaths were reported after heavy rain caused flooding and landslides in parts of Southeast Asia on Wednesday.
Flooding in several northern and central provinces of Vietnam killed seven people and injured at least 34 others, state media reported.
In Thailand, one person died from a landslide in the northern city of Chiang Mai. Several others were injured from flash flooding and landslides in the north of the country, Thailand’s Department of Disaster Prevention and Mitigation said.
The rain was an aftermath of Tropical Storm Kajiki, which made landfall Monday afternoon in central Vietnam, prompting the evacuation of thousands of people located in high-risk areas.
Last year, scientists warned that climate change would lead to warmer seas, which in turn would cause cyclones in Southeast Asia to form closer to land, intensify more rapidly and last longer.
They also raised concerns about the dangers of tropical cyclones happening near the coastline, due to the high population densities in low-lying coastal areas.
Tropical Storm Kajiki also brought strong winds and heavy rainfall to China's southern Hainan Island and nearby parts of Guangdong province on Sunday. At least 20,000 people were evacuated, China's Xinhua News Agency said.
Kajiki weakened to a tropical depression on Tuesday when it moved towards Laos, the national weather agency reported.