BMKG Prepares Gradual Weather Modification to Anticipate El Niño in the Dry Season

Across Indonesia, the OMC strategy will focus on filling water storage structures such as embung (small reservoirs), waduk (reservoirs) and catchment areas as the dry season approaches, to ensure water reserves remain sufficient during prolonged drought. The operation will be carried out even while clouds remain, intervening to fill catchment areas and embungs and reservoirs up to Lake Toba to improve preparedness. BMKG estimates El Niño to become active in June 2026 with moderate to strong intensity, which could prolong the dry season and intensify drought compared with the 30-year average, particularly at the peak period in August–September. Government measures to mitigate drought and forest and land fires are being prepared, with BMKG focusing surveillance on six fire-prone provinces: Riau, Jambi, South Sumatra, West Kalimantan, Central Kalimantan, and South Kalimantan. OMC can only be implemented if there are clouds to seed; interventions are carried out earlier before conditions become truly dry. Previously, BMKG had optimised OMC in the Lake Toba area to maintain water availability for power generation, irrigation and community needs as part of the 2026 dry-season anticipation.