According to its weather-forecast model, a tropical convergence zone is gradually spreading northward and weakening.
From September 12 to September 13, a low-pressure trough is forecast to form across Southern Vietnam, accompanied by weak upper-level wind disturbances.
During the days, residents should be on alert for thunderstorms, lightning, whirlwinds and rainfall of up to 125mm covering Thu Duc, Cho Lon, Con Dao and Bac Tan Uyen.

In the past 24 hours, water levels along the lower Saigon–Dong Nai river system have risen sharply.
At 7 a.m. on September 9, tide levels rose sharply, measuring 1.43 meters at Nha Be station, 1.42 meters at Phu An station, and 1.49 meters at Thu Dau Mot station, already surpassing alarm level 2.
During the period, the peak tides are likely to fall between September 9 and September 11 (from the 18th to the 20th day of the 7th lunar month), occurring at 5 a.m.–7 a.m. and at 5 p.m. –7 p.m.
Residents are recommended to prepare for heavy rain combined with high tides, which may cause waterlogging in low-lying and riverside areas, disrupting traffic and socio-economic activity in Ho Chi Minh City.