India’s southwest monsoon opened June 2026 with a steep 40% rainfall deficit.
This has been driven by strengthening El Niño, an unfavourable Madden–Julian Oscillation and missing low-pressure systems over the North Indian Ocean.
Central, eastern and northeastern regions are worst hit, with over three-quarters of districts reporting deficient to no rain.
The southwest monsoon of 2026 started off with a huge deficit of 40 per cent in June. The reasons for this include the strengthening El Niño conditions in the Equatorial Pacific Ocean, the unfavourability of the Madden Julian Oscillation (MJO) near the Equator and the lack of low pressure areas in the North Indian Ocean region in the current season.
On June 30, 2026, the India Meteorological Department (IMD) stated that the monsoon advanced “into some more parts of Madhya Pradesh, remaining parts of Chhattisgarh, Jharkhand & Bihar, some parts of Uttar Pradesh, most parts of Uttarakhand, and some parts of Himachal Pradesh and Ladakh”. Even though the monsoon winds have covered most areas of the three out of the four homogenous regions in the country, rainfall is much below normal.
From June 1 through June 30, central India suffered from the highest deficit in rainfall of 50 per cent less than the normal. The second highest deficient rainfall was in east and northeast India at 40 per cent below normal. The southern peninsular region experienced rains 27 per cent less than the normal.
Northwest India, where most areas are still waiting for the onset of monsoon, received 31 per cent below normal rains during the same period. Almost all of the June rainfall in northwestern regions of the country has occurred due to western disturbances and other pre monsoon weather systems.
As much as 76 per cent of districts in India have received deficient (20 to 59 per cent below normal), large deficient (60 to 99 per cent below normal) or no rainfall, as of June 29. Among states where monsoon has already arrived the highest deficit in rainfall was in Meghalaya at 76 per cent below normal. Three other states already covered by the monsoon but facing large deficient rains are Manipur (72 per cent), Jharkhand (66 per cent) and Chhattisgarh (66 per cent). Fifteen other states and union territories have also received deficient rainfall from June 1-29.
One of the expected reasons behind the deficit in June rainfall is the El Niño phenomenon. The National Oceanic and Atmospheric Administration (NOAA) of the United States (US) declared the onset of the El Niño on June 11 and predicted it could continue into early 2027. El Niño is the warmer than normal phase of the El Niño Southern Oscillation (ENSO) in the Equatorial Pacific Ocean and generally leads to the suppression of monsoon rainfall over India. The IMD had already factored the development of El Niño into its seasonal forecast for the monsoon in 2026. And it is not just the El Niño acting alone to decrease rainfall.
“El Niño is no longer acting independently especially in our region. The dominance of warming patterns are playing into wind shifts and the pull from the Meiyu-Baiu front during El Niños also plays into delaying the onset and progress. That’s why we have excess rains over the northwest and deficit over the core,” Raghu Murtugudde, visiting professor, Indian Institute of Technology Kanpur and emeritus professor at University of Maryland, told Down To Earth. The Meiyu-Baiu front is a zone of temperature gradient on constant pressure surface from the east China coast to the Pacific Ocean near Japan that is responsible for convective rainfall in that region.
“The energy for Monsoon Intra-seasonal Oscillations (MISO) is missing due to weak monsoon circulation so no low pressure systems are forming,” he added. MISO is a process that occurs several times each year from May to October in the atmosphere over the tropical Indian Ocean, the western tropical Pacific Ocean, and the surrounding land areas, according to the US National Aeronautical and Space Administration (NASA). “MISO events alternate between periods of wetter-than-average and drier-than-average conditions, a cycle that lasts longer than typical weather systems do (1-2 weeks), but shorter than a season (90 days),” according to NASA.
“We are under 8 per cent deficit in June as far as the seasonal total is concerned (as June contributes 20 per cent to the seasonal rainfall). Hopefully we will not get much worse. But we are transitioning from the La Niña winter of 2025-26 into El Niño summer now. This always produces the worse deficit (up to 15 per cent). This maybe the bad news bearer for now,” said Murtugudde.
There could be further movement of the monsoon trough accompanied by rainfall in the coming week, which could be boosted by the formation of low pressure systems in the Bay of Bengal and on land. “But now that the core zone is firing up, we should get a good pull on the trough to move forward,” Murtugudde noted.
“A super crucial week for India as monsoon dynamics are finally showing up on wind patterns later in the week. Dual low pressure area, one formation over inland and another one in bay of bengal along with establishing monsoon axis across north India are the features that will boost India's monsoon rainfall,” wrote independent weather forecaster Navdeep Dahiya on social media platform X (formerly Twitter) on June 30.
“An upper air cyclonic circulation lies over north Bay of Bengal adjoining south Bangladesh in lower & middle tropospheric levels. Under its influence, a Low-Pressure Area is likely to form over northwest Bay of Bengal & neighbourhood around 3rd July, 2026,” according to press release from IMD on June 30.