Mumbai on 'Red Alert' as Heavy Rains Lash City

28 September, 2025

Mumbai has been hit by heavy overnight rains, with a 'red alert' issued by the India Meteorological Department (IMD) for continued heavy to very heavy rainfall. Some parts of the city recorded over 100 mm of rain in a 24-hour period, leading to delays in local train services. The IMD has forecast further intense spells accompanied by thunderstorms and gusty winds, raising concerns about waterlogging, especially during high tide. Similar alerts are in place for the neighbouring districts of Thane, Palghar, and Raigad.

Unpacked:

Why does Mumbai experience such severe flooding during heavy rains?

Mumbai is prone to flooding because of factors like inadequate drainage capacity (up to 55 mm/hour), clogged drains due to garbage dumping, and many low-lying areas where water can't drain easily. When rainfall exceeds drain capacity, especially during high tide, waterlogging and flooding are common even with flood mitigation measures in place.

How do the authorities prepare for and respond to heavy monsoon rains in Mumbai?

The Brihanmumbai Municipal Corporation (BMC) and Western Railway undertake extensive preparations including cleaning and desilting drains, installing pumps, upgrading drainage infrastructure, and deploying early warning systems. The railways also issue monsoon precaution plans and use new technology to minimize disruptions and keep passengers safe.

Is climate change contributing to the increased frequency or intensity of Mumbai’s rains?

Yes, experts link more frequent and intense rainfall in Mumbai to climate-driven changes, especially warmer temperatures in the Arabian Sea, which increase atmospheric moisture and instability. This is expected to make extreme rain events more common in the future, according to climate analyses and local experts.

What impact do these heavy rains and resulting floods have on daily life in Mumbai?

Heavy rains often lead to waterlogging, disruption of local train services (a major commuting mode), flight delays, and flooding in homes and streets. This can halt business activities, endanger lives, and cause severe inconvenience, especially in flood-prone low-lying areas of the city.