Enviro News Asia, Jakarta – Indonesia should strengthen its preparedness for a potentially intensifying El Niño during the second half of 2026, as the climate phenomenon is expected to reduce rainfall, heighten drought conditions, increase the risk of forest and land fires, and place growing pressure on water security and agricultural production.
The warning is based on an analysis of Indonesia’s weather and climate outlook prepared by climate expert A. Karsidi on June 24, which indicates that atmospheric and oceanic conditions through the second 10-day period of June signal a stronger transition into the dry season. The report shows increasingly evident El Niño conditions, while the Indian Ocean Dipole (IOD) remains relatively weak but could shift into a positive phase later this year.
“Indonesia is entering a period of increasingly pronounced El Niño conditions. Sea surface temperature anomalies in the Niño 3.4 region continue to strengthen, and international forecasting models indicate that the phenomenon could persist through the end of the year,” Karsidi said.
According to the analysis, sea surface temperature anomalies in the Niño 3.4 region rose to +1.61 degrees Celsius during the second 10-day period of June, up from +1.40 degrees Celsius in the previous period. The U.S. National Oceanic and Atmospheric Administration (NOAA) has also issued an El Niño Advisory, confirming that both oceanic and atmospheric indicators support the development of the climate phenomenon.
Karsidi said the strengthening El Niño signal suggests that rainfall across much of Indonesia will gradually decline beginning in July, with the most significant reductions expected between August and October.
“The period from August to October 2026 is expected to be the most critical, characterized by widespread rainfall deficits, intensifying meteorological and hydrological drought, and an elevated risk of forest and land fires,” he said.
The report notes that the early stages of the dry season may still experience intermittent rainfall, commonly referred to as a “wet dry season.” This pattern is influenced by intraseasonal climate variability, including the Madden-Julian Oscillation, equatorial wave activity, and relatively warm sea surface temperatures surrounding Indonesia. However, these conditions are expected to weaken as El Niño strengthens.Regions likely to experience dry conditions earlier in July include Java, Bali, West Nusa Tenggara, East Nusa Tenggara, Lampung, South Sumatra, South Kalimantan, and parts of South Sulawesi. Between August and September, below-normal rainfall is forecast to expand across Java, Bali, the Nusa Tenggara islands, South Sumatra, Lampung, Kalimantan, Sulawesi, and Maluku.
Karsidi warned that October could mark the peak of Indonesia’s dry season, with above-average temperatures, declining humidity, prolonged dry spells, higher evapotranspiration rates, and significantly increased wildfire risks.
He emphasized that government policies should extend beyond weather monitoring and focus on anticipatory adaptation measures, including water resource management, forest and land fire preparedness, adjustments to planting calendars, and the strategic use of weather modification operations.
The analysis identifies four major risks requiring immediate attention: meteorological drought, water resource shortages, increased forest and land fire hazards, and disruptions to agricultural production. Parts of Central Java, East Java, West Nusa Tenggara, East Nusa Tenggara, and South Papua have already entered drought alert status.
Karsidi also cautioned that the interaction between a strengthening El Niño and the possible emergence of a positive Indian Ocean Dipole could make the 2026 dry season one of the most severe in recent years.
“The second half of 2026 represents a period that requires heightened national vigilance,” he said.
The report calls on national and regional authorities to strengthen coordination, accelerate mitigation measures, and ensure communities and vulnerable sectors are adequately prepared to minimize the impacts of drought, forest and land fires, and disruptions to food production. (*)
