Cold snaps and heat waves have contributed to tens of thousands of deaths in the United States over the past quarter-century, a new study says. More than 69,000 U.S. deaths occurred between 1999 and 2024 where extreme cold or heat were listed as an underlying or contributing cause, researchers reported Monday in the Annals of Internal Medicine . That's out of a total 69 million deaths -- meaning that 1 in every 1,000 deaths were related to extreme cold or heat, researchers said. "Our findings