Conson was swirling around the southern part of the Hoang Sa archipelago at 01.00pm on September 10, with winds gusting up to 100kph near its eye, reported the National Centre for Hydro Meteorological Forecasting.
In the next 24 hours, the typhoon is anticipated to move to the west at a speed of approximately 10kph and gain its strength.
It will then move slowly and change its course to west and north-west to head toward the central coast of Vietnam.
On September 13 evening, Conson is likely to intensify before bartering central coastal provinces from Thua Thien-Hue to Da Nang.
National weather forecasters say Conson will dump heavy rain on coastal provinces stretching from Thanh Hoa to Quang Binh that may receive 100-200mm of rainfall.
Rainfall totals may also climb as high as 350mm in some localities in Quang Binh and Ha Tinh provinces.
Weather experts also ruled out the possibility of interaction between Conson and super typhoon Chanthu which is moving toward Taiwan (China), not the East Sea.