Typhoon Conson weakened as it headed toward Vietnam, after passing over the Chinese island of Hainan where falling billboards killed at least two people.
The typhoon was downgraded to a tropical storm as it moved past Hainan, the Tropical Storm Risk site (www.tropicalstormrisk.com) said.
Vietnamese police dispersed groups of curious tourists and local people who gathered on the beaches of Hai Phong to watch the high waves, the Voice of Vietnam said in its evening broadcast.
The storm is expected to come ashore in northern Vietnam's scenic Ha Long Bay, near the industrial port of Hai Phong, on Saturday night. The army is evacuating about 150,000 people in its path.
Heavy rain, with strong wind, started falling on Saturday in coastal provinces and sea waves of up to 5 meters (16 feet) pounded the coastline in Nam Dinh province, the radio said.
Strong wind and heavy rain partially cut power in Sanya, a resort city on the southern tip of Hainan, after the first typhoon to hit China this season hit on Friday evening.
A security guard was buried when a billboard toppled over near Sanya, and a motorcyclist died when he was clipped by another falling billboard, China's Xinhua news agency said.
Fishing boats were called back to port from the East Sea.
Several tours to Ha Long Bay and nearby coastal areas this weekend have been canceled and boats have been called back to shore, the official Vietnam News Agency reported.
The Vietnamese government warned that flash floods and landslides could strike mountainous areas after a prolonged dry period has dried up the soil there.
National flag carrier Vietnam Airlines said it had canceled 10 flights in and out of Haiphong and Hanoi on Saturday, including a flight to and from Myanmar's Yangon, having moved part of the affected passengers on domestic flights to Sunday.
Typhoons and tropical storms regularly hit the Philippines, China, Taiwan and Japan in the second half of the year, gathering strength from the warm waters of the Pacific Ocean or East Sea before normally weakening over land.
Conson left at least 39 people dead in the Philippines.
The storm brought wind and rain to the Chinese coastal province of Guangdong, and forced shipping services and flights from Hainan to be halted since Thursday.