Four dead and flights cancelled as Mumbai gets flooding red alert after heavy rains

At least four people are dead and dozens of flights and trains have been cancelled after heavy rainfall flooded the streets of Mumbai this week , prompting a red alert.

Some parts of India ’s financial hub of 21 million people received over 250mm of rain, nearly five times London ’s monthly rainfall,in just six hours on Wednesday. It was the highest single-day rainfall in September since 2020, according to the India Meteorological Department.

At least four people died in rain-related incidents. A woman drowned in an open drain and two labourers were killed by lightning in Kalyan. Another woman reportedly drowned near a waterfall in Khopoli, about 80km from Mumbai.

Operations at Mumbai’s Chhatrapati Shivaji Maharaj airport were severely affected, with at least 36 flights cancelled, causing delays and disruptions for thousands of travellers.

Airlines including SpiceJet, IndiGo and Vistara said they were diverting flights due to the adverse weather.

Local train services, which serve over 7 million people daily, were heavily affected, particularly between Kurla and Thane, where waterlogging stranded passengers.

A large crowd of passengers was seen gathered at the Chhatrapati Shivaji Terminal Station, the city’s largest train station, amid confusion caused by cancellations and delays. The terminal is a vital traffic hub connecting local trains to the intercity and interstate rail network.

A red alert remained in place for Mumbai and neighbouring districts, with authorities asking residents to stay indoors and avoid non-essential travel.

Roads across the city, including in Andheri, Chembur and Vikhroli, were inundated. Schools and colleges were closed as a precautionary measure.

The weather department has forecast more heavy rainfall in the coming days in Mumbai as well as the nearby cities of Pune, Thane and Palghar.

Heavy rainfall often brings Mumbai to a halt as the coastal city’s drainage system struggles to cope with the sheer volume of water. Mumbai is one of the rainiest urban areas in the world, receiving 2,200mm of rain on average between June to September, three times London’s annual rainfall.

Several areas of the city are also at or below sea level, making it vulnerable to high tides, particularly during the monsoon season.

Natural defences such as the mangroves once helped absorb excess water, but these crucial ecosystems have been under increasing pressure due to the relentless expansion of urban development. As structures encroach on these areas, the risk of flooding during heavy rains grows, putting millions of residents at risk.