The Agro Climate Research Centre of Tamil Nadu Agricultural University (TNAU) has projected a mixed Northeast monsoon pattern for 2026, warning that the ongoing El Nino conditions could lead to sharp regional contrasts in rainfall.
According to the district-level outlook for October to December, Tamil Nadu is expected to receive about 468 mm of Northeast monsoon rainfall, close to the long-term average of 464 mm. The Centre noted that this near-normal season may help offset the shortfall recorded earlier in the year.
From June 1 to September 22, the state received 254 mm of rain, around 13% below the long-term average of 292 mm. With the Northeast monsoon contributing roughly half of Tamil Nadu’s annual rainfall, improved inflows could enhance storage in water bodies and support a rise in groundwater levels.
However, the Centre cautioned that El Nino may alter the distribution of rain, with the possibility of cyclone-driven continuous rainfall along coastal districts while interior districts face prolonged dry spells. Farmers were advised to harvest excess rainwater during wet spells by storing it in farm ponds for irrigation during dry periods.
Centre head Sathyamoorthy said the forecast provides expected rainfall totals for the next three months, and that the Northeast monsoon is likely to begin in the second week of October. He added that rain has already been occurring in the Western Ghats belt around Coimbatore, including the Coimbatore Kutralam and Siruvani dam catchment areas, and that the monsoon could become fully established by the third week of October.
