Rescue teams reached the village of Juigaon, 150km south of Mumbai, and began digging for survivors and bodies after a landslide flattened or buried over 30 houses late on Tuesday. Officials estimated 100 to 150 people might have been caught in the avalanche of mud.
"The death toll is likely to increase because we are receiving more reports of deaths from different parts and we have a major landslide," Krishna Vatsa, the state relief secretary, told Reuters.
"In Jui we are estimating about 100 but information is still coming in."
Vatsa said the total death toll elsewhere in Maharashtra State was about 140, including 40 killed in Mumbai.
The army, navy and air force were called in to help as floodwaters swept the Maharashtra coast.
Vatsa said the situation in the worst-affected region south of Mumbai was improving, as the rains had stopped and water levels were receding. But rescue work was hampered because the weather had disrupted their communications networks and they were unable to airlift boats, as planes could not take off.
In Mumbai, meteorologists said heavy rains and high winds were forecast to continue for another 48 hours, after a record 94 cm (37 inches) of rainfall in the north of the city during the previous day.
Electricity and phone links were cut in Mumbai, home to the Bollywood movie industry, schools were shut and commuters were stranded for a second day as trains and buses were cancelled.
"We have already evacuated around 10,000 people," a government spokesman said.
About 40 of the deaths were in Mumbai, including seven children killed by a landslide in the up-market suburb of Andheri.
14-HOUR COMMUTE: Cars and buses were abandoned in the north of the city and thousands of commuters who spent the night in offices or hotels walked 20km or more from the centre to their homes.
Commuter Alex Anthony, 44, said it had taken him 14 hours to reach home in the early hours of Wednesday, walking on rail tracks and wading chest-deep through water.
"It was like a river outside the station," he said. "Firemen tied ropes to lamp-posts and a chain of people held onto it to get through the water."
Trading on Mumbai's bond and currency markets was abandoned, flights in and out of the city were re-routed or cancelled and the government called a state holiday for Wednesday and Thursday, advising people to stay at home.
Companies postponed board meetings and tourists to the city of 15 million people waited for news about their flights, with the lobby of the swanky seafront Taj Mahal Hotel filled with disconsolate travellers and their luggage.
Mumbai Airport, the country's busiest, was clearing its waterlogged runway but by Wednesday evening airlines said they were still not operating.
Outside the city the armed forces helped relief officials air-drop food packets to stranded people.
"The situation is so grave ... we are not in a position to reach out to the people who are in the districts," Chief Minister Vilasrao Deshmukh told Indian television.
The chaos highlighted Mumbai's desperately overloaded and inadequate infrastructure. Authorities have recently begun demolishing slums as part of a hugely ambitious $6 billion plan to turn the city into a new Shanghai.