New Delhi (India), April 13 : India is likely to see below-normal monsoon rains this year, the India Meterological Department said on Monday.
"The quantity of monsoon rainfall this year is expected to reach 92 per cent of the long-period average this year," M Ravichandran, Secretary, Union Ministry of Earth Sciences, said while addressing a press conference here.
He was accompanied by Mrutyunjay Mohapatra, director-general of the India Meteorological Department at the briefing.
The 2026 southwest monsoon seasonal (June to September) rainfall over the country as a whole is most likely to be below normal (95-90 per cent of the Long Period Average (LPA).
Quantitatively, the seasonal rainfall over the country as a whole is likely to be 92 per cent of LPA with a model error of +- 5%. The LPA of the seasonal rainfall over the country as a whole based on the period of 1971-2020 is 87 cm.
Ravichandran said this is the first forecast for the 2026 monsoon, with an updated forecast for the monsoon season to be given in the last week of May this year.
As per the India Meteorological Department (IMD), normal rainfall is defined as between 96 per cent and 104 per cent of a 50-year average of 87 cm (35 inches) for the four-month season.
"It is expected to be 80 per cent this year," Ravichandran said.
"At present, weak La Nina-like conditions are transitioning to neutral conditions over equatorial Pacific and neutral Indian Ocean Diapole (IOD) conditions presently over the Indian Ocean we are expecting the second half of the monsoon period to develop IOD positive," he said.
Latest climate models forecast indicates that the positive IOD conditions are likely to develop towards the end of the southwest monsoon season.
"These two factors in gerneral are both a little bit negative, but the good northern hemisphere snow cover extent during the last three months is slightly favourable so inverse relation between snow and monsoon we will be getting better... Al these put together we will be getting 92 per cent," Ravichandran said.
Atmospheric circulation features across the tropical Pacific remain consistent with weak La Nina-like conditions. The Monsoon Mission Climate Forecast System (MMCFS) suggests the development of El Nino conditions during the South West Monsoon season.
The monsoon in India typically arrives over the southern state of Kerala around June 1 and retreats by mid-September.
Since 2003, IMD has been issuing the operational long-range forecast (LRF) for the southwest monsoon seasonal (JuneSeptember) rainfall averaged over the country as a whole in two stages.
The first stage forecast is issued in April and the second stage or update forecast is issued by the end of May.
In 2021, IMD has implemented a new strategy for issuing monthly and seasonal operational forecasts for the southwest monsoon rainfall over the country by modifying the existing two stage forecasting strategy.
The new strategy uses both dynamical and statistical forecasting system. Multi-Model Ensemble (MME) forecasting system based on coupled global climate models (CGCMs) from different global climate prediction centres, including IMD's Monsoon Mission Climate Forecast System (MMCFS) are used in dynamical forecast system.
As per the new LRF strategy, the first stage forecast issued in middle of April consists of quantitative and probabilistic forecasts for the country as a whole, and the spatial distribution of probabilistic forecasts for the tercile categories (above normal, normal, and below normal) of the seasonal (June-September) rainfall over the country.
The second stage forecast issued around end of May consist of update for the seasonal rainfall forecast issued in April along with the probabilistic forecasts for the seasonal rainfall over the four homogenous regions of India (northwest India, central India, south Peninsula and northeast India) and monsoon core zone (MCZ).
In addition, quantitative and probabilistic forecasts for the country as a whole, and the spatial distribution of probabilistic forecasts for the tercile categories (above normal, normal, and below normal) of the June rainfall over the country are also issued during the second stage forecast.
In continuation to the above forecasts, a monthly rainfall forecast is issued around end of June, July and August respectively for the subsequent one month. In addition, quantitative and probabilistic forecasts for the country as a whole, and the spatial distribution of probabilistic forecasts for the tercile categories for the second half of the season rainfall is issued around end of July along with the forecast for August.