IMD issued a red alert for Mumbai and the neighbouring districts of Thane and Raigad on Thursday, saying that there was a likelihood of heavy to very heavy rainfall, alongside extremely heavy rainfall in isolated pockets.

The red alert for Mumbai shall remain effective till July 26, said the India Meteorological Department.

The catchment areas had continuous rains, causing the lakes at Vihar and Modak Sagar to overflow. This has increased the overall water stock to the point where four of the seven reservoirs that provide the city with drinkable water are now overflowing.

Due to incessant rains, the water level of the Mithi river, which runs through the industrial hub of the city, rose to 2.5 metres, while its danger mark is 4.2 metres

Vihar lake, one of the seven lakes supplying water to Mumbai, started overflowing at around 3.50 am, while Modak Sagar started overflowing at 10.40 am

The IMD forecast that Mumbai will most likely witness occasional gusty winds reaching 50-60 kmph.

According to a civic official, the island city received 44 mm of rain in the 24 hours that ended at 8 a.m. on Thursday, while its eastern and western suburbs received 90 mm and 89 mm of rain, respectively.