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The India Meteorological Department, or IMD, issued a red alert for Mumbai and neighbouring districts like Thane, Palghar and Raigad, warning of "moderate to intense spells of rainfall (two-three centimetres an hour) over the next three to four hours". An orange alert has been sounded for the next four days.
The weather department also said Mumbai and its suburbs will likely receive moderate to heavy rainfall, or thunderstorms, over the next 24 to 48 hours. Isolated places will receive heavy to extremely heavy rainfall in the next two to four days, it said.
An orange alert - also valid for the next four days - has been issued for Konkan districts. A similar alert has been issued for Pune, Satara and Kolhapur districts in western parts of Maharashtra for Saturday and Sunday (as the monsoon moves further inland), and for Bhandara, Gondia and Gadchiroli districts in the Vidharbha region on Sunday.
The western Mumbai suburb of Santacruz recorded 164.8 mm of rain in six hours from 8.30 am, according to IMD data. Colaba, in south Mumbai, recorded 32.2 mm in the same period. According to the civic body, the city and its suburbs (eastern and western) recorded between 48.49 mm to 66.99 mm rain in 24 hours leading up to 8 am.
Four Mumbai subways - Milan, Khar, Andheri and Malad - were closed. Police said the subways were closed after being flooded by at least two feet of water. Traffic in other parts - such as the Western Express Highway and SV Road - has not been affected so far, Somnath Gharge, DCP (Traffic, Western Suburbs) told news agency PTI.
The Brihanmumbai Municipal Corporation has shut down the Hakim Covid vaccination centre in the Byculla area of the city due to waterlogging. The monsoon comes as the city and Maharashtra appear to have seen off the worst of the second wave of infections.
Some local trains - from Mumbai's Chhatrapati Shivaji Maharaj Terminus (CSMT) to neighbouring Thane and Vashi in Navi Mumbai - were suspended due to waterlogging. Routes of some BEST buses - run by the civic body's transport wing - were diverted.
At noon, Central Railway said waterlogging at Chunabhatti and between Sion-Kurla led to suspension of Chhatrapati Shivaji Maharaj Terminus (CSMT)-Thane main line and the CMST-Mankhurd Harbour Line.
At 11.15 am Western Railway said there had been "no disruption in mainline suburban services in Mumbai in spite of very heavy rains in the last three hours". Harbour local line service is operating between Goregaon and Wadalala stations, it tweeted.
The monsoon is expected to advance into the state today and into Telangana and Andhra Pradesh, as well as Odisha and Bengal, over the next 48 hours.
With input from ANI, PTI