Here are 10 developments in this big story:
Cyclone Nisarga made landfall near Alibaug, about 100 km from Mumbai, triggering heavy rainfall and winds with speed up to 110 kilometre per hour, gusting up to 120 kmph.
More than 19,000 people in Maharashtra have been moved to safety. Chief Minister Uddhav Thackeray on Tuesday appealed to the people of the state to "stay indoors". "The cyclone could be more severe than the ones the state has faced till now," Mr Thackeray said. With over 70,000 COVID-19 cases, the state is the worst-hit in the country by the pandemic.
The storm is being continuously tracked by the Doppler Weather Radars or DWRs in Goa and Mumbai. The eye of the cyclone - an area of calm weather in the center of the storm - is visible in the radar, the weather department said this morning. "Eye diameter is about 65 km as observed through radar. thus the diameter has decrease during past 01 hour indicating intensification of system. hence wind speed has increased from 85-95 kmph to 90-100 kmph gusting to 110 kmph (sic)," the weather office tweeted.
In Mumbai, movement of people near coastline is banned till Thursday noon, the police said in a late-night order, adding that anyone caught violating the ban will face criminal action.
The civil aviation regulator - Directorate General of Civil Aviation or DGCA - on Tuesday cautioned airlines about the dangers of operating during monsoon and stormy conditions. Air and rail traffic has been disrupted due to the storm.
A storm surge - as high as two metres (three to 6.5 feet) above the astronomical tide - will inundate the low-lying coastal areas of Mumbai, Thane and Raigad districts during the landfall, the weather department has said.
Fourty-three NDRF (National Disaster Response Force) teams have been deployed in areas expected to be affected along Maharashtra and Gujarat coasts. One NDRF team consists of 45 personnel. "The evacuation is nearly complete. Those in shelters are being trained for life skills and social distancing is being ensured. All preparations are in order. Let's hope we safely ride through the cyclone," NDRF chief SN Pradhan said in a video message this afternoon.
Prime Minister Narendra Modi on Tuesday tweeted: "Took stock of the situation in the wake of cyclone conditions in parts of India's western coast. Praying for everyone's well-being. I urge people to take all possible precautions and safety measures (sic)". In a tweet, his office later said that PM Modi spoke to Maharashtra Chief Minster Uddhav Thackeray, Gujarat Chief Minister Vijay Rupani, assuring all possible help from the centre.
Indian Coast Guard ships and planes have been deployed along the coast to warn fishermen and merchant ships to return to harbour. Maharashtra Chief Minister Uddhav Thackeray's Office (CMO) on Tuesday listed some of the measures that were being taken. These included evacuating those staying in thatched huts. Non-COVID-19 hospitals have been instructed to prepare for any medical emergencies. The state is also taking measures in case of breaks in electricity supply and to secure the nuclear power plant in Palghar district.
Cyclone Nisarga will be the second to strike India's coasts in less than two weeks; last month Cyclone Amphan, one of the worst storms to have formed over the Bay of Bengal in recent years, struck Bengal and parts of Odisha, killing nearly 100 people and affecting lakhs. Bengal Chief Minister estimated the damage done at Rs 1 lakh crore.