People in Tan Chinh Ward in Da Nang City are placing blocks of wood and barrels and boxes of water on their roofs, which often get blown away by storms.
Early on Tuesday morning Storm Noru intensified and moved closer to the central coast.
It lay centered in the southeastern part of the Paracels archipelago at 7 a.m. with maximum winds of 183 kph, up from 149 kph the previous night.
The winds could maintain that strength by 7 p.m. Tuesday, when the storm would be situated 170 km from Da Nang and 120 km from southern neighbor Quang Nam Province, according to the National Center for Hydro and Meteorological Forecasting.