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Tropical cyclone Amphan intensified rapidly in the Bay of Bengal to become a “Super Cyclonic Storm” – the equivalent of a strong Category 4/weak Category 5 on the Saffir Simpson scale. It weakened ahead of landfall on Wednesday 20 May as a very severe cyclonic storm (strong Category 2 equivalent), bringing dangerous winds, storm surge and flooding to coastal areas of West Bengal in India and Bangladesh.

Amphan (pronounced Um-Pun) impacted densely populated areas, including the Indian city of Kolkata (Calcutta)  at a time when restrictions due to the COVID-19 pandemic  is complicating disaster management – and making it more necessary than ever before.

The Indian Meteorological Department in New Delhi, which acts as WMO’s Regional Specialized Meteorological Centre for Tropical Cyclones, warned of a storm surge of up to 4-5 meters above astronomical tide that is likely to inundate low-lying areas of West Bengal during landfall, and of about 2.5 - 3.5 meters for Bangladesh. 

The Bangladesh Meteorological Department for the first time introduced regular storm surge forecasts, thanks to work carried out by the WMO's Coastal Inundation Forecasting project funded by USAID.

RSMC New Delhi accurately predicted that Amphan would make landfall with maximum sustained windspeed of 155-165 km/hour, gusting to 185 km/hour and torrential rainfall, between Digha (West Bengal) and Hatiya Islands (Bangladesh), close to the Sundarbans national park area.

There were no immediate reports on the death toll. Both India and Bangladesh pursue a zero casualty policy.

One million people are being evacuated in India. Bangladesh could equal a new record for evacuations set last November in advance of Cyclone Bulbul, according to the UN Office For Disaster Risk Reduction.

UN humanitarian agencies stepped up preparations in the Rohingya settlements of Cox’s Bazar, home to approximately 1.2 million refugees and host community members.

“Communities are already vulnerable to the devastating health crisis and we know that if people are forced to seek communal shelter, they will be unable to maintain physical distancing and run the risk of contracting or transmitting the disease,” said the International Organization for Migration, which cited government statistics that, as of 18 May, five cases of coronavirus have been confirmed in the refugee population at Cox’s Bazar, based on 140 tests.

The tropical cyclone season in the Bay of Bengal and Arabian Sea has two peaks,  around May and around November and, in the past, the basin witnessed huge casualties.

The deadliest tropical cyclone on record, the Great Bhola Cyclone in November 1970, killed at least 300,000 people in modern-day Bangladesh and led to the establishment in 1972, of a body in charge of the regional coordination mechanism for tropical cyclones, the WMO/ESCAP Panel on Tropical Cyclones

Extensive and coordinated disaster risk reduction campaigns have, in recent years, limited casualties. 

For instance, extremely severe cyclonic storm Fani made landfall in Odisha, India on 3 May 2019. Accurate advance forecasts and a huge, well-coordinated disaster risk reduction campaign, including the evacuation of hundreds of thousands of people, were credited with keeping the death toll to a minimum. This was in contrast to the 1999 Odisha cyclone which caused thousands of deaths in India.