What Happened
- IMD's April 2026 forecast classifies the upcoming southwest monsoon as "below normal or deficient," with projected rainfall at 92% of the Long Period Average (LPA of 868.6 mm).
- A 35% probability is assigned to outright deficiency (below 90% of LPA), compared with the historical base rate of 16%.
- Most of India's major agricultural regions — central, western, and peninsular India — appear in the deficit zone on IMD's spatial probability maps; only extreme northern areas, the northeast, and parts of the northern peninsula are forecast better.
- The Indian Ocean Dipole is currently neutral but expected to turn positive toward the season's end; Eurasian snow cover was slightly below normal in January–March, providing mild offsetting signals.
- IMD will publish a spatial and monthly breakdown in its May 2026 Phase 2 forecast.
Static Topic Bridges
Monsoon Variability and Drought Classification in India
India has one of the world's most variable monsoon systems due to its exposure to both El Niño–Southern Oscillation (ENSO) and the Indian Ocean Dipole. The IMD classification framework distinguishes five rainfall categories — excess, normal, below normal, deficient, and large deficient — each carrying distinct implications for water storage, agriculture, and human welfare.
- Drought in India is officially classified into meteorological drought (rainfall deficiency), hydrological drought (depletion of surface and groundwater), and agricultural drought (soil moisture deficit affecting crops).
- The Drought Management Framework under the National Disaster Management Authority (NDMA) requires states to activate contingency crop plans when districts receive less than 50% of normal rainfall in the first two weeks of the sowing season.
- Central India (Madhya Pradesh, Chhattisgarh, Maharashtra) and parts of Rajasthan are the most drought-prone regions with lowest groundwater buffer.
- India experienced severe droughts in 2002, 2009, and 2015, all linked to El Niño years; agricultural GDP contracted by 4–7% in each episode.
Connection to this news: With a 35% probability of deficient rainfall and most central Indian states already in the deficit zone on IMD's map, state governments will need to activate drought contingency plans well ahead of kharif sowing.
Eurasian Snow Cover as a Monsoon Predictor
The extent of snow cover over Eurasia during the winter and spring months (January–March) is one of the oldest and most reliable predictors used in monsoon forecasting. Reduced snow cover allows the Eurasian landmass to heat up faster in spring, strengthening the land-sea temperature gradient that drives the monsoon onset and intensity.
- Below-normal Eurasian snow cover in January–March has a positive correlation with above-normal monsoon rainfall; above-normal snow cover is associated with delayed onset and weaker monsoon.
- The mechanism: less snow → faster spring heating of central Asia → steeper pressure gradient between the subcontinent and the Indian Ocean → stronger low-level monsoon jet.
- The 2026 below-normal snow cover reading provides a mild positive signal, partially counterbalancing the negative El Niño signal.
- IMD incorporates snow cover data from the NOAA/NESDIS Northern Hemisphere weekly snow and ice dataset.
Connection to this news: The January–March 2026 snow cover reading (slightly below normal) is one reason IMD's forecast settles at 92% rather than deeper into the deficient range — it represents a partial but insufficient offset to the El Niño headwind.
Reservoir Storage and Water Resource Management
Monsoon rainfall directly determines the filling of India's major reservoirs, which supply drinking water, irrigation, and hydroelectric power throughout the year. Deficient monsoon seasons reduce reservoir levels heading into the following rabi season and summer, triggering water allocation conflicts between irrigation and urban supply.
- India's 150 major reservoirs (monitored weekly by the Central Water Commission) have a total live storage capacity of ~178 billion cubic metres (BCM).
- A below-normal monsoon typically leaves reservoirs at 60–70% of capacity by September-end, compared with 85–90% in normal years.
- Hydropower generation from major projects (Bhakra, Hirakud, Nagarjunasagar) drops by 15–20% in deficit years, intensifying power cuts and raising thermal power dependence.
- The National Water Policy (2012) prioritises drinking water as the first use of water resources, ahead of irrigation and industry.
- IMD's Reservoir Storage Monitoring System provides weekly updates and triggers early warning alerts to state governments.
Connection to this news: A below-normal to deficient 2026 monsoon would reduce reservoir filling during the only annual replenishment window, creating a multi-month cascade of water stress through rabi 2026–27.
Key Facts & Data
- Forecast rainfall: 92% of LPA (~799 mm), with ±5% model error
- LPA (1971–2020): 868.6 mm
- Deficient probability: 35% (historical: 16%)
- Regions most at risk: central, western India, large parts of peninsular India
- Relatively better outlooks: northeast India, extreme north, parts of northern peninsula
- IOD: neutral, transitioning to positive by season-end
- Eurasian snow cover (Jan–Mar 2026): slightly below normal
- India's major reservoir monitoring: Central Water Commission (CWC) — 150 reservoirs, 178 BCM capacity
- Historical drought years with El Niño: 2002, 2009, 2015 — agricultural GDP fell 4–7% in each