At 07:00a.m. the tropical depression was about 420km east and southeast of the Hoang Sa (Paracel) archipelago of Vietnam, with winds gusting 61kph near its centre.

In the next 24 hours, the tropical depression will be moving west and northwest at a speed of between 10-15kph, and is likely to gain further strength into a tropical storm.

The tropical depression will cause rough seas of 2-4m high waves, said the National Centre for Hydro-meteorological Forecasting.

This is a complicated tropical depression and the centre is closely monitoring its track to release timely warnings, it said.

With El Nino fading away and La Nina coming, the stormy season this year is anticipated to be complicated.

It is expected that between 6 and 8 tropical depressions/tropical storms will form in the East Sea, with 2-4 of them expected to batter the mainland of Vietnam from now till October 2024.