Mai Van Khiem, director of the National Centre for Hydro-meteorological Forecasting, said Sinlaku is the fourth storm to develop in the region this year.
According to the Japan Meteorological Agency, the storm’s centre was about 3,000 km east of the Philippines as of 9 am, with maximum sustained winds at level 9 and gusts up to level 12.
The storm is forecast to strengthen rapidly over the next two days, reaching level 13 by April 12 and potentially intensifying to level 15, while moving west, northwest and then northwest at around 15 kph.
Forecasters said it is likely to curve northwards under the influence of a subtropical ridge before heading towards southern Japan, making the chances of entering the East Sea very low.
Such a trajectory is typical of early season storms in the northwest Pacific, which often follow a parabolic path.
The National Centre for Hydro, Meteorological Forecasting said the number of storms and tropical depressions in the East Sea this year is expected to be below average. The basin typically records about 12.7 systems annually, with around five affecting Vietnam’s mainland.
However, authorities warned of the risk of strong or rapidly intensifying storms with complex and unpredictable tracks.