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The cyclone is very likely to cross north Odisha-West Bengal coasts between Paradip and Sagar Island, met office chief M Mohapatra has told NDTV. The maximum wind speed of Yaas is expected to be up to 185 km per hour between 5.30 and 11.30 am along the north Odisha coast as the cyclone approaches the land.
Around 3 million people in Odisha and half a million people in Bengal have been evacuated from their homes. Officials said it has been a challenge to provide them accommodation while maintaining social distancing.
Odisha Chief Minister Naveen Patnaik took stock of the situation in coastal districts, where heavy rain coupled with strong winds have started. "Every life is precious, thus all possible steps should be taken to protect life," he said.
Odisha's districts of Jagatsinghpur, Kendrapara, Bhadrak and Balasore districts are likely to be affected. In Bengal, the districts of West Midnapore, North and South 24 Parganas -- and state capital Kolkata -- may experience storm with wind speeds of up to 120 km per hour.
Bengal Chief Minister Mamata Banerjee has announced she will stay at the state secretariat tonight to monitor the rescue and relief operation. Governor Jagdeep Dhankar visited the secretariat in the evening.
The army has deployed 17 columns-- each with around 100 men -- in Bengal, nine of them have been stationed in Kolkata. The rest are in Purulia, Birbhum, Bardhaman, Howrah Hooghly, Nadia and North 24 Parganas districts.Besides, National Disaster Response Force teams, 54,000 officers and relief workers, 2 lakh police and Home Guard personnel, will also be deployed.
Flight operations at the Kolkata airport will be suspended from 8:30 am to 7:45 pm today, reported news agency ANI quoting airport administration.
NDRF chief SN Pradhan said a record 115 teams have been deployed across five states and one Union Territory.
National Disaster Management Authority member Kamal Kishore told NDTV that they have advised hospitals and healthcare organisations to make contingency arrangements for power and oxygen supply.
While conditions in Bay of Bengal -- including high surface temperature of water -- are conducive for cyclones, experts attributed their increasing frequency and intensity to climate change. The super cyclone of 1999 had killed around 10,000 people in Odisha.