The southwest monsoon has started showing signs of revival over Maharashtra and is expected to reach Mumbai within the next 48 hours, according to the India Meteorological Department (IMD). The weather agency also clarified that the rainfall Mumbai received on Monday was not monsoon rain but pre-monsoon showers.

Monsoon Regains Momentum After Brief Pause

The monsoon's progress had slowed significantly last week, raising concerns over delayed rainfall in several regions. However, IMD officials now say conditions have improved, especially along India's western coast, allowing the monsoon to move forward again.

The revival has created favorable conditions for the monsoon to advance gradually across more parts of Maharashtra and further inland into central India.

Despite the improvement, rainfall remains well below normal across the country. IMD data showed that India's overall rainfall deficit stood at 43% on Monday.

Experts Expect Gradual Progress

OP Sreejith, scientist and head of the climate monitoring and prediction group at IMD, said the weather department had already predicted a revival around June 22 and 23.

“The monsoon has seen a slight revival, particularly on the western side. We had forecast the same a few days ago, that it should pick up again around June 22 and 23. However, a low pressure area over the Bay of Bengal is still missing and should only develop towards the end of the month,” he said.

He added that the monsoon is likely to move forward slowly until a stronger weather system develops. “We can only expect gradual progress in the coming days till the end of the month, when it should finally pick up intensity,” he added.

Missing Low-Pressure System Slows Advance

Meteorologists say the absence of a low-pressure area over the Bay of Bengal continues to limit the monsoon's strength and spread. Mahesh Palawat, vice-president of private weather forecasting agency Skymet, said the recent improvement should be viewed as only a temporary revival for now.

He explained that a low-pressure system over the Bay of Bengal is expected to form around June 29, which could significantly improve monsoon activity.

“This delays progress into UP and Delhi. We may expect that only towards the first week of July,” he added. Delhi typically receives the southwest monsoon around June 27.

Monsoon Advances Across Several States

According to the IMD, the southwest monsoon advanced further on June 22 into additional parts of the central Arabian Sea, Maharashtra, Telangana, Karnataka, Chhattisgarh, Odisha, Jharkhand and Bihar.

The weather department said conditions remain favorable for further advancement into the remaining parts of the central Arabian Sea and additional areas of Maharashtra, including Mumbai, during the next two days. The monsoon is also expected to spread further into Telangana, Odisha, Chhattisgarh, Jharkhand and Bihar.

On Monday, the northern boundary of the monsoon passed through Alibag, Pune, Nizamabad, Dantewada, Balangir, Sundargarh, Chatra, Gaya and Muzaffarpur.

Maharashtra Experienced Delayed Monsoon Activity

The IMD had earlier announced the arrival of the monsoon in parts of Maharashtra on June 8, just four days after it reached Kerala. However, most regions of the state received very little rainfall after that. Weather experts attributed the slowdown to the absence of localized weather systems over both the Bay of Bengal and the Arabian Sea, along with the influence of El Niño conditions.

Under normal circumstances, Mumbai receives the monsoon around June 11.

Rainfall Deficit Remains Severe

Rainfall figures continue to show a significant shortfall across India. By June 22, the country should have received 106 millimetres of rainfall based on the long-period average (LPA). However, actual rainfall has reached only 60.6 millimetres so far.

Central India has recorded the largest deficit at 67%. East and northeast India are experiencing a 40% shortfall, while south peninsular India remains 28% below normal. Northwest India has performed relatively better but still shows a 15% rainfall deficit compared to the seasonal average.

El Niño May Affect Monsoon Performance

The IMD has forecast that India will receive about 90% of its long-period average rainfall during the 2026 monsoon season. Weather experts expect El Niño conditions to continue influencing rainfall patterns, particularly during the second half of the season. This could suppress rainfall activity and increase the risk of below-normal precipitation in several regions.

For now, meteorologists are watching for the formation of a low-pressure system over the Bay of Bengal, which could help strengthen the monsoon and accelerate its advance across northern and central India.