Cyclone Fani is beginning to make landfall in eastern India.
The country's Meteorological Department says wind speeds will reach 195 km/h (121 mph) when the storm is at full force.
More than a million people in the state of Orissa have already been forced to leave their homes.
Several neighbouring states in India have also been put on high alert.

Sydney Airport flights disrupted due to air traffic controller shortage
Fire in rebel-held east Congo kills 24 schoolchildren
Trump says he does not regret Iran war despite potential impact on elections
Trump touts $5,000 payout if Republicans win as Vance waits in wings
Search expands after Philippine ferry fire kills five and leaves dozens missing
