According to the Brihanmumbai Municipal Corporation, no major waterlogging was reported anywhere in the city or the suburban regions on Monday. However, flooding was witnessed in some of the low-lying areas in the city.

Early on Monday morning, around 3 am, the weather office took to X and said, “Light to moderate spell of rainfall is likely to continue over Mumbai and suburban areas during next 3-4 hours.”

The weather forecast for the day, as per IMD, is “generally cloudy sky with heavy rain”. The minimum temperature on Monday is likely to settle at 24 degrees Celsius, while the maximum is expected to be around 31 degrees Celsius. The weekly weather prediction board for Mumbai showed rain being consistent for this entire week.

IMD rain alerts for Mumbai

According to IMD, a well-marked low-pressure area was lying over south madhya Maharashtra and adjoining areas of Marathwada and North Interior Karnataka on Sunday, May 25. It stated that the area is likely to move eastwards during the next 24 hours, and then would eventually weaken.

The weather office forecast that scattered to fairly widespread light to moderate rainfall along with thunderstorms, lightning and gusty winds is reaching Konkan and Goa, Madhya Maharashtra during May 25-27.

The Madhya Maharashtra region is under orange alert for Monday, with the regional weather office forecasting “very heavy rain with thunderstorms and lightning, squall, etc”.

Eight weather stations in Mumbai are under red alert – Borivali, Santacruz, Powai, Mulund, Chembur, Worli, Colaba, and Alibag. The weather stations of Navi Mumbai, Thane, and Kalyan are under orange alert.

IMD also issued a ‘Nowcast’ warning for isolated places in Mumbai, forecasting thunderstorms along with lightning and intense rainfall with gusty winds in the next three to four hours.

Suburban train services hit

The heavy rainfall and thunderstorm resulted in power visibility in several parts of the city, delaying the suburban services on the Central and Western Railway.

A spokesperson of the Central Railway said, “Suburban trains are delayed by eight to 10 minutes because of reduced speed on account of low visibility due to incessant downpour.”

Meanwhile, a spokesperson of the Western Railway said that the suburban services were running normally on its corridor but, some passengers have complained about delays on social media.

Southwest monsoon in Maharashtra

The southwest monsoon arrived in Maharashtra on Sunday, making it the earliest onset of the annual rainfall season over the state in 35 years, the weather office said.

It added that the monsoon is expected to advance to Mumbai and some other parts of the state over the next three days.

Southwest monsoon made an onset over Maharashtra on May 20 in 1999, IMD scientist Sushma Nair was cited as saying by news agency PTI.

Kerala also witnessed an early arrival of the southwest monsoon on Saturday. Usually, it marks its onset over Kerala by June 1 and then reaches Maharashtra around June 7, and Mumbai on June 11.

A monsoon expert and former secretary of the Ministry of Earth Sciences, M Rajeevan, said that early onset and coverage of large areas on the first day itself is not uncommon.

“In 1971, the monsoon at the time of onset covered a larger area in Karnataka and parts of Maharashtra. Present active monsoon conditions will continue at least till June 2 and will help to advance monsoon into Maharashtra and eastern parts of the country.