Nari is expected to slam into central Vietnam on Tuesday morning, after ripping off rooftops, toppling trees and triggering flash floods in the northern Philippines over the weekend.
"Very strong winds are expected from Monday. There might be heavy rains of up to 500 millimeters over the next few days," said Bui Minh Tang, head of Vietnam's national weather forecast centre.
Authorities in the central provinces of Thua Thien Hue and Da Nang were moving roughly 66,000 people in vulnerable coastal area to safety, according to the state-controlled Tuoi Tre newspaper.
Boats have been urged to seek shelter and food has been prepared for residents in case of prolonged flooding, reports said.
Vietnam is hit by around eight to 10 tropical storms every year, often resulting in loss of life and heavy material damage.
Last month Typhoon Wutip left a trail of destruction in the communist state, ripping the roofs off nearly 2,00,000 houses and leaving several people dead, according to state media.
Forty people have been killed in flooding in Vietnam since early September, according to an official toll.


Latest News from World News Desk