According to the national centre for hydro meteorological forecasting, the system strengthened from a low pressure area and was located about 3,000 kilometres east of the Philippines as of 7 am on April 9.
The depression is packing winds of 50 to 61 kilometres per hour, with gusts reaching level 9 on the Beaufort scale.
Situated along the eastern edge of a subtropical high pressure ridge, the system is forecast to move slowly westward over the next 24 hours, with a high likelihood of strengthening into a storm.
If upgraded, it would be the fourth storm to form in the northwest Pacific this year.
Forecasters said the system is expected to follow a typical early season path, curving northward before turning west northwest towards waters south of Japan. Current projections indicate little chance of it entering the East Sea.
The Japan meteorological agency has issued a similar assessment under the framework of the world meteorological organisation.
Vietnamese authorities said they will continue to monitor the system closely.
