North Sumatra Waters Set to be Hit by High Waves, 23–26 May 2026

Fishermen using boats are advised to exercise caution when wind speeds reach 15 knots and wave heights reach 1.25 metres.

Medan (ANTARA) – The Meteorology, Climatology and Geophysics Agency (BMKG) says that several waters in North Sumatra are potentially exposed to high waves from 23 to 26 May 2026 and must be watched carefully as they could disrupt navigation, especially for fishermen using boats.

‘Waves could reach heights of 1.5 to 2.5 metres, potentially occurring from 23 to 26 May 2026,’ said Rizki Fadhillah Pratama Putra, BMKG forecaster at the Belawan Maritime Class II Meteorology Station in Medan, on Friday.

The wind pattern in the East Coastal waters of North Sumatra generally moves from West to North with wind speeds ranging from 2 to 15 knots.

Meanwhile, the wind pattern in the West Coastal waters of North Sumatra generally moves from West to Northeast with wind speeds ranging from 6-15 knots

High waves can occur in the West North Sumatra waters, Batu Islands waters, East of the Nias Islands waters, West of Batu Islands waters, West of the Nias Islands waters and the western Indian Ocean off the Nias Islands.

Fishermen using boats are advised to be cautious if wind speeds reach 15 knots and wave heights reach 1.25 metres; likewise, barges should exercise caution if wind speeds reach 16 knots and wave heights reach 1.5 metres.