BMKG Predicts Potential Rain in 17 Indonesian Regions Today

The Meteorology, Climatology, and Geophysics Agency (BMKG) has announced the potential for rain in 17 regions across Indonesia today, Tuesday, September 22nd. According to BMKG, while dry conditions still dominate most of Indonesia, moderate to heavy rainfall is expected to occur locally. Several factors are predicted to influence the potential for rain over the next week. Specifically, for the first and second ten-day periods of October 2026 (Dasarian I and II Oktober 2026), rainfall exceeding 150 mm per ten-day period is predicted for the western coast of Aceh and the western coast of North Sumatra. Rainfall is also anticipated during the period of September 18-24, 2026, in northern to central Sumatra, northern to central Kalimantan, central to southern Sulawesi, Papua Mountains, and Papua. This potential for rain is influenced by several atmospheric dynamics, including the Equatorial Rossby Wave, which is predicted to be active in North and West Kalimantan. Additionally, the Kelvin Wave is expected to be active in eastern Kalimantan, the northern coast of East Java to NTT, Sulawesi, Maluku, North Maluku, and western and northern Papua, supporting the formation of rain clouds. A cyclonic circulation is also predicted to form in the South China Sea, causing areas of wind convergence and deceleration that extend across several regions. "Supported by strong local instability, the process of lifting air masses becomes quite optimal, thus potentially increasing the possibility of rain in the affected areas," explained BMKG. The regions with potential for rain on Tuesday, September 22nd, are as follows: (Note: While the original text does not list all 17 specific regions, areas mentioned like 'northern to central Sumatra, northern to central Kalimantan, central to southern Sulawesi, Papua Mountains, and Papua' are likely included.)