Some suburbs have seen more than 300 mm of rain in the 24 hours to Tuesday morning and more heavy rain is expected over the next two days, said India Meteorological Department (IMD) official K.S. Hosalikar.
The department issued a red alert for the city for the next two days and civic authorities advised people not to venture out unless absolutely necessary.
Trains, already running skeleton services due to the novel coronavirus lockdown, were suspended in several places because of flooding and traffic was disrupted on some of the city's main roads.
A landslide swept down a slope onto a main road in a northern suburb, media reported.
There was no impact on operations at Mumbai's airport apart from reduced visibility, a representative said.
The city struggles with the monsoon rains every year as widespread construction and rubbish-clogged drains and waterways make it increasingly vulnerable to flooding.
Mumbai is also struggling with a surging coronavirus outbreak with an average of 1,000 new cases being reported every day.
The number of Covid-19 cases rose to 1,855,745 in India as 52,050 new cases and 803 deaths were registered during the past 24 hours, bringing the national death toll to 38,938, showed the data released by the health ministry, Xinhua reported.
Tuesday was the sixth consecutive day when over 50,000 fresh cases were detected across the country in a single day.
There are a total of 586,298 active Covid-19 cases in the country.
So far 1,230,509 people have been cured and discharged from hospitals, said the health ministry.
The sudden surge in Covid-19 cases in india is mainly attributed to the ramped-up testing facilities across the country.
Till Monday, 20,864,750 samples had been tested, out of which 661,892 samples were tested on Monday alone, according to the indian Council of Medical Research (ICMR).
Did you find this article insightful?
100% readers found this article insightful