Mumbai, with a population of more than 18 million, hadn’t been hit by a cyclone in more than a century, raising concerns about its readiness. There were no preexisting cyclone shelters in the city due the rarity of storms, said National Disaster Response Force spokesman Krishan Kumar.
"We moved people to other strong buildings where there is a supply of water,” he said.
Satellite photos showed the storm developing an eye as it neared landfall.
As Cyclone Nisarga crossed the central state of Maharashtra, live TV coverage showed inky black clouds framing the Arabian Sea, and trees swaying wildly as rain pounded coastal towns and villages.
So far, no deaths or major damage have been reported as workers began clearing fallen trees and other debris along India's western coastline.
About 100,000 people were evacuated from low-lying areas in Maharashtra and neighboring Gujarat, according to the Press Trust of India news agency.
Both states, already among the hardest hit by the coronavirus pandemic, activated disaster response teams, fearing extensive flooding could further impair overwhelmed health systems.
Many of the large and sturdy shelters in Mumbai had been converted into coronavirus isolation or treatment facilities. About 10,000 residents were evacuated from their homes, according to municipal officials.
High winds in Mumbai, home to Bollywood and India's largest stock exchange, whipped skyscrapers and ripped apart shanties near the beach.
Homes in city slums were boarded up and abandoned, and officials patrolled the streets, using bullhorns to order people to stay inside.
Such storms are less common in the Arabian Sea than on India’s east coast, and usually form later in the year.
Nisarga came barely two weeks after Cyclone Amphan struck, devastating parts of Kolkata on the east coast and killing more than 100 people in India and neighboring Bangladesh.
Before the storm's arrival, about 200 COVID-19 patients in Mumbai were moved from a field hospital beneath a tent to another facility to avoid strong winds.
“If hospitals and clinics are damaged by the cyclone, the city won’t be able to cope with the large number of COVID-19 cases, and social distancing measures will become virtually impossible to follow,” Bidisha Pillai, chief executive of Save the Children in India, said in a statement.
S.N. Pradhan, director of India's National Disaster Response Force, said social distancing norms were being followed in evacuation shelters.
“Let us fight this danger like we are standing up to the corona pandemic and are on our way to defeat it. Likewise, we will prevail over this situation too!” Maharashtra's top official, Chief Minister Uddhav Balasheb Thackeray, tweeted.
As of Wednesday, there are 208,800 cases of COVID-19 in India with at least 5,834 deaths, according to Johns Hopkins University.
The Associated Press contributed to this report.