BMKG issues warnings for high waves and tidal flooding in Java

The Meteorology, Climatology, and Geophysics Agency (BMKG) has issued warnings for significant maritime and coastal hazards across parts of Java, Indonesia, in late October 2026.

In the southern waters of the Special Region of Yogyakarta (DIY), high waves between 2.5 and 4 meters are expected from October 23 to 26. This risk affects the waters of Kulon Progo, Bantul, and Gunung Kidul, driven by easterly winds and cyclonic activity near Aceh and Papua. BMKG advises fishermen to exercise caution, noting that wind speeds and wave heights pose specific risks to fishing boats, barges, and ferries.

Simultaneously, the coastal areas of East Java face threats of tidal flooding (rob) from October 26 to 29. This phenomenon is triggered by the combination of a full moon on October 26 and the perigee phase on October 29. Potential impact zones include West Surabaya (Gresik, Lamongan, Tuban), the Port of Surabaya (North Surabaya, Benowo, Kalianak, Krembangan), and the East Surabaya coast (Sidoarjo, Pasuruan, Probolinggo). The flooding is expected to disrupt port activities, residential areas, salt ponds, and inland fisheries.