The Can Tho Hydrometeorological Station said the water level at Can Tho station reached 2 metres at 5 am on September 26, up 0.10 metres from 1.90 metres at 4.30 am a day earlier.
It was the first time during the current high-tide period that the water level had reached warning level three.
The September 26 reading was 0.15 metres below the 2.15 metres previously forecast, while the expected peak for the period was revised down from 2.33 metres to 2.28 metres.
Water levels are forecast to rise rapidly from September 27 to 29, reaching 2.10 metres on September 27 and 2.20 metres on September 28.
The highest tide is expected at around 5.30 pm on September 29 at 2.28 metres, 0.28 metres above warning level three.
Levels are then forecast to ease gradually but remain high, with peaks of 2.23 metres on September 30, 2.13 metres on October 1 and 2.08 metres on October 2.
The station said rapidly rising water levels on the Hau River, combined with high tides and local rainfall, could cause deep flooding in Binh Thuy and Cai Khe and localised flooding in Ninh Kieu, Cai Rang and other low-lying areas outside dykes.
City agencies have been instructed to closely monitor weather and water levels, inspect dykes, embankments and drainage systems, and operate tidal-control sluices and pumps where necessary.
Traffic authorities have also been asked to deploy personnel to flood-prone roads, while schools may adjust class times or suspend classes in areas where deep flooding disrupts transport.
Local authorities were told to prepare rescue and evacuation plans for residents in high-risk areas.
Residents have been advised to closely follow weather and flood warnings, particularly from September 27 to 30 when water levels are expected to remain high.
The forecast peak of 2.28 metres is just 0.01 metres below Can Tho's record of 2.29 metres, set on October 22, 2025. That level surpassed the previous record of 2.27 metres recorded on October 12, 2022.
