The Forecast: Below Normal Rain Ahead
The India Meteorological Department (IMD) has projected a 'below-normal' monsoon for the second half of the season, covering August and September 2026. Specifically, rainfall for August is forecast to be less than 94% of the Long Period Average (LPA),
a benchmark used to measure seasonal performance. This outlook is largely attributed to the strengthening El Niño conditions over the Pacific Ocean, a phenomenon typically associated with weaker monsoon winds and reduced rainfall over the Indian subcontinent. After a June with deficit rainfall was balanced by a near-normal July, the projection for a drier August and September has put farmers, policymakers, and economists on alert.
What Is the 'National Average'?
When the IMD talks about 'normal' or 'below-normal' rain, it's comparing the forecast to the Long Period Average (LPA). This LPA is the average rainfall received over the entire country during the southwest monsoon season, calculated over a 50-year period, which is currently 1971-2020. The seasonal LPA for India stands at 87 cm. Any rainfall between 96% and 104% of this average is considered 'normal'. A forecast like the current one—below 94%—is classified as 'below-normal'. This single number has long been the headline figure for judging the monsoon's success, influencing everything from agricultural planning to economic forecasts.
The Problem with a Single Number
The latest forecast highlights a growing problem: a national average can be deeply misleading. While the all-India figure might sound moderately low, it often conceals drastic regional variations. A country as vast and geographically diverse as India rarely experiences a uniform monsoon. The current IMD outlook itself states that while many parts of the country will likely see below-normal rain, some areas in peninsular, central, and northeast India could receive normal to even above-normal rainfall. This uneven distribution means that while one region suffers from drought-like conditions affecting crop sowing, another could be battling floods and waterlogging. In July, for instance, even with nationally 'normal' rain, the distribution was uneven, with 46% of districts experiencing deficit rainfall.
Regional Realities Tell a Different Story
Focusing on the national average obscures the lived reality in different states. For example, past 'normal' monsoon years have seen severe deficits in agrarian states like Bihar, Jharkhand, and Uttar Pradesh, while parts of Telangana and Tamil Nadu received large excess rainfall leading to floods. This year's forecast continues that trend of sharp contrasts. Even as the headline number points to a deficit, the IMD has also issued alerts for heavy rainfall in states like Madhya Pradesh, Chhattisgarh, and parts of the Northeast for early August. This paradox—a national deficit coexisting with regional deluges—is why experts argue that focusing solely on the LPA is becoming increasingly inadequate for effective water management and agricultural advisories. The story of the monsoon is not one story, but hundreds of district-level narratives.
A Shifting Baseline in a Changing Climate
Adding another layer of complexity is the fact that the 'normal' itself is changing. The IMD periodically updates the LPA baseline to reflect more recent climate data. The current baseline (1971-2020) represents a slightly lower average rainfall than the previous one. This means that what is considered 'normal' today is actually less rain in absolute millimetres than it was a few decades ago, a subtle but significant sign of a drying trend in some regions. This shift makes it even more crucial to move beyond percentages and look at the actual volume of water available in specific river basins, reservoirs, and agricultural zones. The scrutiny is no longer just about predicting the monsoon, but about how we define and measure it in an era of climate change.
