The government said it was still urging fishermen back to shelter despite typhoon Peipah, 400 km (250 miles) off Vietnam, weakening into a tropical depression. Rescue and sea patrols have been deployed off 19 coastal provinces from Quang Binh to Ca Mau, urging fishermen to take shelter, the government said in a report.
Storms and floods have killed nearly 200 people in central provinces since early October, and caused damage of US$300 million.
They have delayed the coffee harvest in the Central Highlands coffee belt, squeezing supplies to global markets.
More rain will also disrupt the harvest, which has just started after rain kept growers indoors in the last week of October, the usual start of the harvest.
Rain could also disrupt outdoor drying, delaying the delivery of robusta beans to Saigon Port for loading. It takes about 10 days to pick, dry and bag coffee cherries before delivery to the port in Ho Chi Minh City.
Agriculture and health officials also said receding floods could help spread bird flu now hitting ducks in Quang Tri province and make more people sick with the acute diarrhoea which has infected more than 1,200 people in the country.
The government was sending 5,500 tonnes of rice to feed flood victims in five central provinces as floods and rain have washed away their food stocks.
(Reporting by Ho Binh Minh; Editing by Michael Battye)