Cyclone Yaas, over 600km away from Bangladesh, is gaining momentum and is likely to make landfall somewhere on Odissa-West Bengal coast tomorrow, according to the Met office.

It said Yaas had wind speeds between 62kph and 88kph and that it could turn into a very severe cyclonic storm with wind speeds from 89kph to 117kph before making landfall.

The Met office said the cyclone was likely to move towards the Indian coast but it could change course and come towards Bangladesh.

"Earlier, cyclone Bulbul that was initially moving towards Bangladesh changed its course and moved towards India. So we need to be alert about the cyclone with full preparation," said Abdul Mannan from the Storm Warning Centre of Bangladesh Met office.

Mannan has been monitoring the cyclone since its formation.

"Even if it does not move towards Bangladesh, coastal areas near the Sundarbans will face peripheral effects of the cyclone during the full moon, when the normal high tide will be at least 12 feet high," he said.

The Met office said the sea would be rough and advised all maritime ports to hoist cautionary signal number two, which means all fishing boats and trawlers should move close to the shore.

Enamur Rahman, state minister for disaster management and relief, yesterday said the government was ready to deal with Yaas.

During a meeting on the preparations to tackle Yaas, he said, "Police, Ansar, BGB personnel and volunteers of Cyclone Preparedness Programme are ready. They will work according to instructions."

In Barisal the government has taken preparation to evacuate 20 lakh people if necessary.

Our correspondents in coastal districts have already started reporting rain in their districts.

The capital witnessed heavy showers late last night.