BMKG Issues National Alert for Extreme Weather Conditions Through Early 2026

Weather Patterns Driven by La Niña

The Indonesian Meteorology, Climatology, and Geophysics Agency (BMKG) has issued a national alert regarding the continuation of extreme weather conditions through the end of 2025 and into early 2026. According to BMKG Chief Teuku Faisal Fathani, the current global atmospheric dynamics are still influenced by the weak La Niña phenomenon, which is directly impacting increased rainfall across various Indonesian regions ¹

The La Niña condition is characterized by lower sea surface temperatures in the Pacific and Indian Oceans compared to Indonesian waters, which are relatively warmer. This temperature difference triggers air mass flow towards Indonesia, forming high convective clouds that potentially result in heavy rainfall ¹

Regional Weather Projections

BMKG forecasts that the peak of the rainy season will occur in January 2026 in several key regions, including Sumatra Selatan, Java, Nusa Tenggara, Papua Selatan, and Sulawesi Selatan. In February 2026, while some areas will still experience high rainfall, regions like Aceh, Sumatra Utara, Riau, and Jambi will begin transitioning towards drier conditions ³

The agency has particularly warned about potential forest and land fires in February, especially in central and southern Sumatra Utara. Rainfall intensity is expected to be particularly high in Jawa Tengah, with some areas in Banten, Jawa Barat, Jawa Tengah, and Bali potentially receiving rainfall up to 200 mm ¹

Tropical Cyclone Monitoring and Impacts

BMKG is closely monitoring tropical cyclone systems in Indonesia's southern region. On December 25, 2025, a tropical cyclone embryo (96S) was detected, which developed into Tropical Cyclone Haily on December 26, although it didn't reach strong cyclone status. Another cyclone embryo (98S) was monitored north of Australia on December 27, 2025 ¹

The indirect impacts of these cyclone systems have been felt in Bali, NTB, and NTT, with increased rainfall intensity, strong winds, and sea waves reaching 1.2 to 2.5 meters in southern waters. BMKG emphasizes that weather information aims to protect public safety rather than discourage tourism ¹

Government and Public Response

The Ministry of Maritime Affairs and Fisheries (KKP) has also issued warnings to fishermen about extreme weather conditions. KKP's Director General for Capture Fisheries, Lotharia Latif, emphasized that safety is the top priority and urged fishermen not to force themselves to sea during adverse weather conditions ²