⁠Mumbai Braces For Rainy Week: Heavy Rainfall Likely Due To Formation Of Low-Pressure Area

Mumbai is on alert for a wet and potentially disruptive week ahead, as weather models suggest the formation of a low-pressure area near the Konkan coast and adjacent Arabian Sea by May 22. This development, driven by a confluence of atmospheric systems, is expected to bring widespread and intense rainfall across the city and surrounding regions.

According to IMD, a cyclonic circulation is likely to form off the Konkan coast within the next 24 hours. Meanwhile, a separate weather system currently situated over the Bay of Bengal near South Coastal Andhra Pradesh and North Tamil Nadu is projected to move inland over the next 36 hours. Once this system travels westward and converges with the circulation over the Arabian Sea, conditions will become ripe for the development of a low-pressure area, intensifying rainfall across Maharashtra’s coastal belt.

As per IMD's latest Nowcast warnings issued at 4 pm on Monday; an Orange alert has been issued for Thane, Pune, Nasik, Raigad, and Latur Districts. A yellow alert has been issued for Mumbai. Red alert has been issued for Ahmednagar, Solapur and Osmanabad districts on the possibility of moderate thunderstorms with an intense spell of rain.

Apart from Palghar, Ratnagiri, Sindhudurg, Kolhapur and Washim - all the remaining districts have been issued a yellow alert on the possibility of moderate thunderstorms with wind speed up to 40-60kmph.

Mumbai is expected to witness light showers beginning Monday, May 19, with rainfall gradually increasing in intensity through the week. On May 20, moderate and scattered rain is likely to continue. However, it is midweek — particularly May 22 and 23 — when the city could be lashed by heavy rainfall. The rainfall could be intense enough to cross the three-digit mark in 24 hours, the weather agency added.

Usually, May remains a relatively dry month for Mumbai, averaging just 11.3 mm of rain. Pre-monsoon showers in May are uncommon, and heavy rainfall events are rare. The last notable downpour occurred on May 31, 2006, when the Santacruz station recorded 180 mm of rain in a single day. This upcoming spell could be of a similar intensity and possibly arrive earlier in the month.

Meanwhile, the India Meteorological Department (IMD) predicted isolated heavy to very heavy rainfall over south Madhya Maharashtra, Konkan and Goa from May 19 to 25 and isolated heavy rainfall over Marathawada region between May 19 and 21.

This round of showers will mark Mumbai’s first major rainfall event of 2025. It could lead to waterlogging and flooding in low-lying areas. On May 22 and 23, the heavy rain could disrupt daily commutes, leading to traffic snarls on roads. Even flight schedules could be affected, the weather agency warned.

So far in May 2025, the Santacruz observatory has recorded 41 mm of rain, which is above the monthly average. Colaba, on the other hand, has notched up 84 mm. With further rainfall expected in the coming days, these numbers could rise sharply.

Meteorologists note that while this week’s rains are still categorised as pre-monsoon activity, they could pave the way for an earlier arrival of the southwest monsoon.

The southwest monsoon made further progress on May 19, advancing over additional parts of the south Arabian Sea, south Bay of Bengal, central Bay of Bengal, and northeast Bay of Bengal. According to the latest IMD bulletin, conditions remain favourable for the monsoon to advance further into more regions of the south Arabian Sea, as well as additional parts of the south, central, and northeast Bay of Bengal over the next two to three days.

In Mumbai, the southwest monsoon is likely to arrive ahead of its usual onset date of June 11.