Signing you in

Monsoon rainfall over the country is likely to be below normal at 90% of the long period average (LPA), with a model error of ±4%, the India Meteorological Department (IMD) said on Friday, lowering its earlier forecast of 92% of the LPA issued in April.

Visitors at the Marine Drive on a rainy afternoon, in Kochi. (PTI)The LPA of monsoon rainfall over the country during June to September, based on data from 1971 to 2020, is 87 cm.

However, according to the forecast probabilities issued by IMD, there is a 60% probability of a “deficient” monsoon (below 90% of LPA), a 24% probability of a “below normal” monsoon (90-95% of LPA), a 14% probability of a “normal” monsoon (96-104% of LPA), a 2% probability of an “above normal” monsoon (105-110% of LPA), and zero probability of an “excess” monsoon (above 110% of LPA).

“The forecast probability is not the only factor. We have issued the 90% of LPA forecast based on the total quantity of rainfall that we are likely to receive during the season. So we look at dynamic factors also,” said M Ravichandran, secretary, ministry of earth sciences.

Also Read: Monsoon concerns deepen as rainfall forecast falls to 90% of normal

It is a bigger concern for the agriculture sector as the southwest monsoon’s seasonal rainfall over the monsoon core zone (MCZ), which includes most of the country’s rain-fed farmlands, is also likely to be below normal at below 94% of LPA.

IMD said rainfall is most likely to be normal over Northeast India (94-106% of LPA) and below normal over Central and South Peninsular India (below 94% of LPA) and Northwest India (below 92% of LPA).

During June to September 2026, below-normal seasonal rainfall is most likely over most parts of the country, except some areas in Northwest and Northeast India, eastern parts of the south peninsula and adjoining east-central India, and isolated pockets of East India, where normal to above-normal rainfall is likely.

Also Read: Brutal June, above-normal heat wave days, rain forecast cut further: Key IMD projections

Though it was earlier expected that June rainfall would not be impacted by approaching El Nino conditions, IMD in its updated forecast said average rainfall for the country during June 2026 is most likely to be below normal at below 92% of LPA.

During June, below-normal monthly rainfall is very likely over most parts of the country, except some parts of Northwest India, Northeast India and the south peninsula, along with isolated pockets of central India, where normal to above-normal rainfall is likely.

“We can expect weak El Nino conditions to set in as early as June,” said Ravichandran.

Currently, neutral El Nino-Southern Oscillation (ENSO) conditions are transitioning towards El Nino conditions over the equatorial Pacific region, IMD said.

The latest climate model forecasts indicate that El Nino conditions are likely to develop during the southwest monsoon season. Neutral Indian Ocean Dipole (IOD) conditions currently prevail over the Indian Ocean and are likely to continue during the monsoon season. In India, El Nino is associated with harsher summers and weaker monsoons.

IMD’s extended range forecast now shows largely dry conditions over Kerala between May 28 and June 4, with only marginal improvement expected between June 4 and June 11.

Rainfall is expected to pick up after June 11, according to the latest forecast. Two factors are likely to delay or weaken the monsoon onset over Kerala — a typhoon developing over the West Pacific, which is pulling significant moisture away from the Arabian Sea and Bay of Bengal, and a cyclonic circulation over the Lakshadweep region that is limiting rainfall over Kerala.

The monsoon normally reaches Kerala around June 1. On May 15, IMD had forecast that the southwest monsoon would set in over Kerala on May 26, with a model error of ±4 days.

Also Read: Satellite imagery shows massive cloud belt over north, central India; Delhi braces for more rain

“We are expecting that monsoon will gradually advance to more parts of Arabian Sea and extreme Peninsular India during next one week. Most of the rainfall now is happening over the ocean and not on the mainland. So we have not declared monsoon onset over Kerala yet,” Ravichandran said.

The monsoon remains crucial for India’s economy as nearly half of the country’s net-sown area lacks irrigation facilities. The rainy season also replenishes reservoirs that support power generation, industries and drinking water supply.

This year’s monsoon will be particularly significant as farmers also face concerns over possible fertiliser supply disruptions because of the conflict in West Asia.

IMD has also warned of a particularly hot June. Above-normal heatwave days are expected over many parts of Uttar Pradesh, Haryana, Punjab, Bihar, Odisha, Chhattisgarh, Gujarat and Andhra Pradesh, along with isolated regions of Maharashtra, Telangana, Himachal Pradesh and Tamil Nadu. However, below-normal heatwave days are likely over Rajasthan and Jharkhand.

Some of these regions are expected to witness five to six heatwave days during June.

“Normally three heatwave days are expected in these regions. But we are expecting two to three additional heatwave days in June,” said M Mohapatra, director general, IMD.

IMD warned that the increased likelihood of heatwave conditions during June 2026 may significantly impact public health, water availability, power consumption and essential services.

Vulnerable groups, including the elderly, children, outdoor workers and people with pre-existing health conditions, remain particularly at risk from prolonged exposure to extreme heat.

Persistent high temperatures may also place additional stress on infrastructure and resource management systems.

In view of the anticipated conditions, state governments and district administrations have been advised to undertake preparedness measures, including ensuring the operational readiness of cooling shelters, availability of safe drinking water, and enhanced health surveillance and emergency response systems.

IMD said it will continue issuing weekly and extended-range forecasts, along with early warnings and impact-based forecasts, to help authorities prepare for heatwave conditions. The public has also been advised to stay updated with official forecasts and take precautions such as staying hydrated and avoiding exposure during peak afternoon hours.

I write on the environment and climate crisis and I believe these are the most important stories of our times.