The Indonesian government has used 97.8 tons of seeding materials like sodium chloride and calcium oxide in the Weather Modification Operation (OMC) since January 12, 2026, to control extreme rain in the Jabodetabek area. The operation involves BNPB, BMKG, TNI AU, and local BPBDs, with potential extension until February 1, 2026, to prevent flooding. Jakarta Governor Pramono Anung stated that funding has been allocated for this effort.
The Weather Modification Operation (OMC) was launched on January 12, 2026, by the National Disaster Management Agency (BNPB), the Meteorology, Climatology, and Geophysics Agency (BMKG), the Indonesian Air Force (TNI AU), and the Regional Disaster Management Agencies (BPBD) of DKI Jakarta and West Java provinces. Its goals are to accelerate rainfall over the ocean and inhibit the formation of new rain clouds to reduce flood risks in densely populated areas like Jabodetabek.
By January 26, 2026, a total of 97.8 tons of seeding materials had been dispersed through 112 flight sorties using six aircraft from Halim Perdanakusuma Air Base in Jakarta and Husein Sastranegara Air Base in Bandung. The materials consisted of 57.6 tons of Sodium Chloride (NaCl) and 40.2 tons of Calcium Oxide (CaO). The fleet included four Cessna Caravan 208B aircraft (PK-JVH, PK-YNA, PK-SNG, PK-SNK) and two Casa 212 aircraft (A-2105, A-2107). The operations cover airspace over Jakarta, West Java, and Banten.
On the 12th day of operations, DKI Jakarta's BPBD conducted four sorties seeding 3.2 tons of materials, including 800 kg of NaCl over northern Jakarta waters and 2.4 tons of CaO over South Jakarta, Bekasi, and Bogor Regency. DKI BPBD's Acting Head, Isnawa Adji, stated: "On the 12th day, we conducted four flight sorties as an effort to suppress high rainfall."
Jakarta Governor Pramono Anung has opened the possibility of extending the OMC until February 1, 2026, due to BMKG's forecast of heavy rain. "BMKG's results indicate a possibility that weather conditions until February 1 will still require OMC. The budget has been allocated, so if needed, we will proceed," Pramono said on January 27, 2026. He emphasized that efforts include border areas like Tangerang, Bogor, and Bekasi to reduce incoming floods. Jakarta's river system can only handle up to 150 mm of daily rainfall, and mid-January floods were caused by high-intensity rain plus upstream flows.
"The most important thing is to prevent high rainfall from causing major floods again. That's what we're anticipating," Pramono added. This operation is part of the government's hydrometeorological disaster mitigation strategy.
