BMKG: High Waves Up to 4 Metres Expected in Indonesian Waters Early June

The Indonesian Meteorology, Climatology, and Geophysics Agency (BMKG) has warned of potential high waves up to four metres in several sea areas during early June 2026, posing significant risks to national maritime safety.

BMKG Maritime Meteorology Director Eko Prasetyo urged all sea transport operators, ship captains, and traditional fishermen to remain vigilant and adhere to safe operational limits from 30 May to 2 June 2026.

“High waves in these areas could endanger maritime safety. The BMKG advises the public, especially fishermen using transport vessels, to stay alert,” Prasetyo stated in a press release on Saturday, 30 May 2026.

He detailed that fishing boats are highly vulnerable if sailing with wind speeds exceeding 15 knots and wave heights above 1.25 metres, while barges face high risks with winds over 16 knots and waves exceeding 1.5 metres.

Ferry vessels have safe operating parameters of wind speeds below 21 knots and maximum wave heights of 2.5 metres.

Larger vessels such as cargo ships or cruise liners should exercise caution when wind speeds surpass 27 knots and waves exceed 4.0 metres.

The highest risk areas currently include the North Natuna Sea, northern Strait of Malacca, and the western Indian Ocean near Aceh, where waves of 2.5 to 4.0 metres are expected due to winds of up to 25 knots.

Additionally, moderate waves ranging from 1.25 to 2.5 metres are forecast across a wide area, from the southern Indian Ocean off Java to East Nusa Tenggara (NTT), northern Makassar Strait, Sulawesi Sea, Banda Sea, and Arafura Sea.