Context:
The India Meteorological Department (IMD) forecasts 105% of Long Period Average (LPA) rainfall for 2025 (± 5% margin).
- LPA for 1971–2020 stands at 87 cm
- Rainfall classification:
- Deficient: < 90% of LPA
- Below Normal: 90–95%
- Normal: 96–104%
- Above Normal: 105–110%
- Excess: > 110%
Forecast Accuracy and Methods
- IMD’s first monsoon forecasts have historically shown discrepancies, accurate only 8 times in 20+ years within ±5% range
- Accuracy improved since 2021 using multi-model ensemble dynamical systems, combining global climate models and statistical tools
- Dr. M.N. Rajeevan, ex-Secretary, Ministry of Earth Sciences, credits this system for reduced errors
Rainfall Trends and Regional Variability
- 2024 monsoon was ‘above normal’ (108%), aiding good harvests
- 2023 monsoon was ‘below normal’, with stark geographical disparities:
- Excess rainfall: Tamil Nadu, Telangana, Puducherry
- Deficient rainfall: Bihar, Jharkhand, East UP
Climate Factors Influencing Monsoon
- 2025 is expected to see neutral ENSO (El Nino–Southern Oscillation) conditions
- This means neither El Nino (dry) nor La Nina (wet) will affect monsoon
- Indian Ocean Dipole (IOD) can still impact rainfall patterns — positive IOD supports rainfall
Impact on Agriculture and Food Inflation
- Strong 2024 monsoon led to:
- 3.6% agricultural output growth
- 5.7% rise in foodgrain production
- Easing of food inflation: fell from 8% (Dec 2024) to below 6% (Jan 2025)
- Food inflation dipped below headline inflation in March 2025 — first time since July 2023
- 2024-25 production estimates:
- Foodgrains: 166 million tonnes
- Cereals: 159 million tonnes
- Rice: 121 million tonnes — highest growth in a decade
Challenges and Outlook
- Spatial rainfall distribution remains critical:
- 2024 excess rain damaged onion crops in Maharashtra
- Deficient rain delayed paddy sowing in Punjab, Gangetic plains
- Rising temperatures, not just rainfall, now a primary driver of food inflation, says HSBC report
