New Delhi, The super cyclone Amphan, whirling in the Bay of Bengal, could cause widespread damage to the coastal districts of West Bengal and Odisha, said India Meteorological Department (IMD) Director General Mrutyunjay Mohapatra, here on Monday.

"Amphan is the second super cyclone after the one that hit Odisha in 1999. It was historically the most intense cyclone," Mohapatra said. The 1999 super cyclone had killed more than 9,000 people.

He said Amphan, a cyclone with 700 km spread and around 15 km in height, was rotating at 220-230 km per hour speed at its centre. It was moving northwards at 7 km/h during the past six hours and was centred around 730 km south of Odisha's Paradip, 890 km south-southwest of West Bengal's Digha and 1,010 km south-southwest of Bangladesh's Khepupara.

The super cyclone is expected to make a landfall between the Digha island and the Hatiya island of Bangladesh, close to the Sundarbans, on May 20. The weather agency has issued an orange alert for coastal West Bengal and Odisha, where it said widespread damage was expected.

Mohapatra said the cyclone could cause multi-hazard -- tidal wave, strong wind and heavy rain.

He said rain in West Bengal's coastal districts, like South and North Parganas, West and East Medinipur, Hoogli, Howrah and Kolkata, would begin on May 19 and wind would blow at 55-65 kmh. The tidal wave is expected to be 4-6 feet above the astronomical tide.

"After the super cyclone makes a landfall, wind will start blowing at 165-195 km/h with heavy to extremely heavy rainfall. This wind speed could cause large-scale damages," the Director General said.

It could uproot trees, communications and power transmission poles, bend telephone lines and cause extensive damage to houses, crops and plantations, he said.

Mohapatra said the cyclone would have early impact on the north coastal districts of Odisha, like Jagatsinghpur, Kendrapara, Bhadrak and Balasore.

"The impact will, however, not be direct as the cyclone is moving parallel to the state. From today (Monday) night, the north Odisha districts will witness 110-130 km/h wind," he said.

Fani was the last extremely severe cyclone to hit Odisha in May 2019.

While the frequency of cyclones had decreased over the Bay of Bengal, the severity had increased, Mohapatra said.