IMD projects 105% of long-period average rainfall for June–September monsoon season; neutral ENSO and IOD conditions expected to persist.
Published on: April 17, 2025
By: [PIB]
Location: New Delhi, India
The India Meteorological Department (IMD) has released its first long-range forecast for the 2025 southwest monsoon season, projecting a stronger-than-normal monsoon across the country. According to the forecast, India is likely to receive 105% of the Long Period Average (LPA) rainfall during the June to September monsoon season, with a model error margin of ±5%. The LPA for seasonal rainfall over the country is pegged at 87 cm, based on the 1971–2020 average.
The forecast is grounded in both dynamic and statistical prediction models, which point towards favorable atmospheric and oceanic indicators, such as neutral El Niño–Southern Oscillation (ENSO) and neutral Indian Ocean Dipole (IOD) conditions throughout the season. Notably, the atmospheric circulation currently resembles La Niña-like patterns, which typically aid in boosting monsoon rainfall.
In addition, reduced snow cover over the Northern Hemisphere, particularly across Eurasia, during the January–March period is seen as a positive indicator. Historically, lower snow extent in these regions is inversely correlated with stronger Indian summer monsoons.
The IMD has classified the rainfall probability under five categories:
- Below Normal (<90% of LPA): 2%
- Near Normal (90–95% of LPA): 9%
- Normal (96–104% of LPA): 30%
- Above Normal (105–110% of LPA): 33%
- Excess (>110% of LPA): 26%
Thus, there is a 59% combined probability that India will experience above-normal to excess rainfall this year.
Spatial forecasts suggest that most parts of India, excluding some areas in the northwest, northeast, and southern peninsular regions, are likely to witness above-normal precipitation. However, IMD cautions that white-shaded regions on their probability maps indicate areas with no clear model signal, suggesting equal chances for all three categories of rainfall.
The IMD will issue an updated second-stage forecast by the end of May 2025, which will provide more granular insights, including region-wise projections for northwest India, central India, the monsoon core zone, the southern peninsula, and the northeast.
This forecast comes under the revised long-range forecast (LRF) strategy adopted in 2021, which combines traditional two-phase outlooks with monthly and seasonal updates, utilizing multiple coupled global climate models, including the Monsoon Mission Climate Forecast System (MMCFS).
With this encouraging outlook, the agricultural, water management, and energy sectors may find reasons for optimism heading into the peak cropping season.
