The cyclonic storm "Phailin" has been classified as "very severe" by the Met department and is heading towards coastal Odisha and Andhra Pradesh where it is expected to hit on Saturday evening.
Here are the 10 big developments in this story:
Experts say the wind speed will touch 175-185 km per hour when the cyclone hits the coast of Northern Andhra Pradesh and Southern Odisha.
Strong winds with a speed of upto 65 km per hour will hit both states tomorrow morning, the Met department has forecast. (Track LIVE updates)
Heavy rainfall is expected for Odisha and Andhra Pradesh on Saturday, with lots of rain forecast for Bengal the next day.
The Andhra Pradesh government says it has informed the Navy, Army and Air Force that their assistance may be required for emergency and relief operations.
Due to the cyclone alert, thousands of power sector employees from the Seemandhra region of Andhra Pradesh, who were on strike to protest against the Centre's decision to split the state, have decided to return to work for now. (Read: Seemandhra power strike ends - temporarily, warn unions)
Large parts of the 13 districts of Seemandhra had been without power for six days because of the strike.
Lakhs of government employees from other deparments who have been on strike have also said that they will help with any relief and rehabilitation work by temporarily returning to work if the cyclone hits.
The Visakhapatnam Cyclone Warning Centre has warned fishermen against venturing into sea.
A super-cyclone had struck 14 coastal districts of Odisha in October 1999. Nearly 10,000 people were killed as winds raging at 300 km per hour tore through the coast.
In Odisha, 14 districts are now on high alert.
