Hundreds of people are feared to have died during record-breaking temperatures in the Pacific Northwest and western Canada.
Officials have set up cooling centers, distributed water to the homeless, and took other steps as the mercury climbed as high as 46C in cities such as Seattle and Portland.
The death toll in the state of Oregon reached 79. In Canada, British Columbia’s chief coroner Lisa Lapointe said there were reports of at least 486 “sudden and unexpected deaths” between last Friday and Wednesday.
In Oregon’s Multnomah County, the oldest person to die was 97 and the youngest 44.
Authorities in the county turned nine air-conditioned county libraries into cooling centres, where 7,600 people cooled off between Friday and Monday. Officials acknowledge this is not enough, and say there are lessons to be learned.
Washington state authorities have linked more than 20 deaths to the heat, but officials said that number is likely to rise.
Oregon’s office of emergency management director Andrew Phelps said: “Learning of the tragic loss of life as a result of the recent heat wave is heartbreaking. As an emergency manager – and Oregonian – it is devastating that people were unable to access the help they needed during an emergency.”
Among the dead was a farm labourer who collapsed on Saturday and was found by fellow workers in rural St Paul, Oregon.
The workers had been moving irrigation lines, a spokesman for the state’s worker safety agency said.
Oregon Occupational Safety and Health (OSHA) is “exploring adopting emergency requirements, and we continue to engage in discussions with labour and employer stakeholders”.
The spokesman added that employers are obligated to provide ample water, shade, additional breaks and training about heat hazards.
An executive order issued in March 2020 by Oregon governor Kate Brown would formalise protecting workers from heat, but it is coming too late for the dead farmworker.
Ms Brown’s order focuses on reducing greenhouse gas emissions and also tells the Oregon Health Authority and Oregon OSHA to jointly propose standards to protect workers from excessive heat and wildfire smoke.