A powerful pre-monsoon cyclone roared ashore in southern Bangladesh on Sunday with sustained winds above 195 kilometers per hour, after an unprecedented evacuation of more than two million people from the Khulna and Barisal coastal belts shielded the country from what forecasters had warned could be the deadliest storm of the decade.

Cyclone Amphan III, the third Bay of Bengal system in six years to bear that designation, made landfall near the mouth of the Pussur River shortly before 11 a.m. local time, tracking northeast across the Sundarbans mangrove belt and into the polder country south of Khulna city. The Bangladesh Meteorological Department classified it as a “very severe cyclonic storm” at landfall, the second-highest tier on the national scale, with a peak gust of 232 kilometers per hour recorded at the Hiron Point coastal station before instruments failed.

Initial assessments late Sunday counted at least 17 confirmed deaths across the impacted districts and more than 800 injuries, figures that disaster officials said would almost certainly rise once communications were restored to outlying chars and that nonetheless represented a fraction of the toll feared 72 hours earlier. Roughly 14,800 houses had been fully destroyed and another 96,000 partially damaged in early field reports compiled by the Department of Disaster Management, with the heaviest concentrations in Mongla, Shyamnagar, Koyra and the coastal upazilas of Patuakhali.

“The wind was inside the house with us,” said Rahima Begum, 54, a farmer interviewed at a cyclone shelter in Kalapara after she rode out the storm with 1,200 other evacuees in a three-story concrete refuge built under a World Bank coastal-resilience program. “But we were in the building. My grandchildren were in the building. That is the difference from before.”

The evacuation, which began Friday afternoon and ran through Saturday night, mobilized more than 76,000 Cyclone Preparedness Programme volunteers, a network jointly run by the Bangladesh Red Crescent Society and the government that has expanded substantially since Cyclone Sidr killed roughly 3,400 people in 2007. Mosques, schools and the country’s purpose-built cyclone shelters, of which more than 14,000 are now distributed across the coastal belt, absorbed the bulk of the displaced. Loudspeakers, mobile-phone alerts in Bangla and Rohingya, and door-to-door sweeps in remote chars cleared communities the meteorological department had marked as inside the storm’s wind- and surge-impact corridor.

“The forecast track was unusually steady from Wednesday onward, which gave us the window we needed,” said Mohammad Mosharraf Hossain, secretary of the Ministry of Disaster Management and Relief, at a Dhaka briefing Sunday afternoon. “We do not yet know our final losses. But the death toll from a storm of this size in this place, in a previous era, would have been measured in the tens of thousands.”

Storm surge of 3.4 meters was recorded at the Mongla port gauge before it was overtopped, with provisional estimates pointing to inundation of 5 to 5.5 meters across the western Sundarbans, flooding deep into the mangrove belt and submerging a band of polder villages along the Shibsa and Pussur rivers. The mangrove cover absorbed an unquantified share of the storm’s energy but suffered visible damage, with early aerial reconnaissance from the Bangladesh Air Force showing extensive defoliation and uprooted Sundri trees across the Khulna range.

In the world’s largest refugee settlement, at Cox’s Bazar in the country’s southeast, more than 1.1 million Rohingya residents experienced heavy rain bands and gusts but escaped the cyclone’s core. Aid agencies said landslide risk inside the camp blocks would remain elevated for at least 48 hours as saturated hillsides settled. The UN refugee agency said it had pre-positioned shelter kits and tarpaulin for 320,000 people before landfall, and that joint patrols with Bangladeshi civil-defense units had begun damage surveys in Camps 8W, 13 and 18 on Sunday afternoon.

Dr. Saima Wazed, the World Health Organization’s regional director for South-East Asia, said in a statement from New Delhi that initial concerns centered on waterborne disease in the days ahead, with thousands of tubewells in coastal Khulna and Bagerhat submerged in saline storm surge. “We have learned from Aila, from Sidr, from Amphan and from Mocha that the cyclone is the first event and the cholera and skin infections are the second,” she said. “The window to pre-position oral rehydration salts and chlorination is now.”

The Indian Meteorological Department in New Delhi said the storm’s eye was projected to track north-northeast over the next 36 hours, weakening to a deep depression by Tuesday morning but spreading heavy rainfall across West Bengal, Tripura and into Assam. Authorities in the Indian Sundarbans evacuated roughly 280,000 people from low-lying islands including Sagar, Mousuni and the Pathar Pratima group on Saturday in coordination with their Bangladeshi counterparts; West Bengal Chief Minister Mamata Banerjee’s office said no deaths had been reported on the Indian side as of Sunday evening.

Climate scientists pointed to unusually warm sea-surface temperatures across the Bay of Bengal — running 1.4 to 1.8 degrees Celsius above the 1991–2020 baseline through the first week of May — as a key driver of Amphan III’s rapid intensification, which saw the storm jump from a tropical storm to a Category-equivalent 4 system in roughly 30 hours. “What we are watching in the Bay is a thermodynamic environment increasingly hostile to a stable pre-monsoon window,” said Dr. Roxy Mathew Koll, a climate scientist at the Indian Institute of Tropical Meteorology in Pune. “Storms are spinning up faster and topping out higher. The forecasters and the evacuation system are running to stay even.”

International offers of assistance moved quickly. The European Union activated its Civil Protection Mechanism and pledged an initial 12 million euros in emergency relief, Japan committed $20 million through its disaster grant facility, and a senior State Department official, speaking on condition of anonymity, said USAID was preparing a disaster declaration that would unlock initial relief contracting on Monday. Saudi Arabia and the United Arab Emirates each announced airlifts of shelter materials departing Sunday night.

Power had been restored to roughly a third of affected substations by Sunday evening, mobile-network operators reported partial service returning across Khulna and Barisal divisions, and the Mongla and Payra ports remained closed pending channel surveys. Disaster-management officials said additional casualty figures, shelter-return guidance and structural-damage assessments would be released as field teams reached the outermost chars over the next 48 hours.