India's monsoon has entered a break phase. The rain-bearing trough has drifted to the Himalayan foothills, El Nino is strengthening, and the IMD expects subdued showers over much of the country this week. (Photo: Windy)

Why has the monsoon ghosted half of India? El Nino and a shifting trough explained

India's monsoon has entered a break phase, with the rainfall deficit near 14 per cent and El Nino strengthening in the Pacific. The IMD forecasts subdued rain over northwest, west-central and south peninsular India, with revival hopes pinned on a fresh low pressure system.

by · India Today

In Short

  • India's monsoon rainfall deficit stands near 14 per cent nationally
  • Monsoon trough has shifted north, triggering a classic break phase
  • El Nino strengthening in Pacific, IMD pins hopes on IOD

The clouds are still there. The rain is not. For a country that spent all of June scanning the sky, July began with a promise. A depression, which is a strong low pressure system, spun out of the Bay of Bengal in the first week and drenched Odisha and central India.

The monsoon finally covered the entire country on July 9, only a day behind schedule, and the national rainfall deficit shrank from 30 per cent at the end of June to about 14 per cent.

Then the monsoon simply stopped showing up. Meteorologists have a name for this. It is called a break.

WHAT IS A MONSOON BREAK?

Think of the monsoon trough as the spine of the rainy season. It is an elongated belt of low pressure that normally stretches from Northwest India to the head of the Bay of Bengal, pulling in moist winds and squeezing rain out of them over the heart of the country.

During a break, this spine drifts north towards the Himalayan foothills. The hills and the Northeast get lashed, while Central and peninsular India are left staring at dry skies. Scientists have documented this rhythm for decades, and it is playing out now almost by the textbook.

This is only the third time in 11 years that the monsoon has weakened this sharply in July, after 2015 and 2021.

The India Meteorological Department (IMD) has said subdued rainfall is likely over the plains of Northwest India, West-Central India and the Southern Peninsula for the next six to seven days.

Dry westerly winds have already crept into states like Madhya Pradesh, nudging even that surplus state into deficit.

WHY IS THE 2026 MONSOON SO WEAK?

June set a miserable stage. The country received just 99.5 mm of rain, roughly 40 per cent below normal and the fifth lowest for the month since records began in 1901.

Three culprits stand out. First, El Nino, the abnormal warming of the central and eastern Pacific Ocean, developed in June and is strengthening. It disturbs global wind circulations and typically starves the Indian monsoon of moisture.

The Indian Ocean Dipole acts as a natural counterweight to El Nino's drying effect on India. In 1997, a strong positive IOD saved India from drought despite a raging Super El Nino. In 2026, the IOD remains neutral and offers no such protection. (Infographic: Radifah Kabir/India Today)

Second, the Madden-Julian Oscillation, a pulse of clouds and winds that circles the equator every 30 to 60 days, has been stuck in phases that suppress rain over India.

Third, the Bay of Bengal has produced barely any low pressure systems, the engines that drag the trough south and deliver soaking rain inland.

WHEN WILL THE RAIN RETURN?

The first real answer arrived on Wednesday morning. At 5.30 am on July 15, a fresh low pressure area, only the second of the season, formed over the northwest Bay of Bengal off the north Odisha-West Bengal coast, according to the IMD.

Odisha is already feeling it. The IMD has issued a red alert warning of extremely heavy rainfall, with heavy to very heavy showers expected till July 17. The system is forecast to move west-northwestwards across North Odisha and Gangetic West Bengal, enhancing rain over East and Northeast India, eastern Uttar Pradesh and the Western Himalayan region through the week.

Dark clouds cover the skies as India's monsoon enters a break phase, leaving the rainfall deficit near 14 per cent. (Photo: PTI)

Independent forecasters echo this optimism, noting the system could intensify into a well-marked low pressure area soon. It is already feeding moisture into central and western regions, they say, with potential heavy showers in parts of Gujarat. If it tracks favourably, it may coax the monsoon trough southwards and shorten the break.

Beyond that, forecasters are watching the Indian Ocean Dipole, a see-saw of sea temperatures in the Indian Ocean. If its positive phase develops by late August, it could blunt El Nino's edge. Until then, July, the wettest month of the year, is running on borrowed rain.

- Ends