ER visits for heat-related illnesses spike — and hard-hit places aren’t always the hottest

As heat blankets much of the US, hospitals in many states are already seeing extremely high rates of heat-related emergencies, according to data compiled by the U.S. Centers for Disease Control and Prevention, and forecasters say more abnormally warm weather is on the way.

As heat blankets much of the US, hospitals in many states are seeing extremely high rates of heat-related emergencies, according to data compiled by the US Centers for Disease Control and Prevention, and forecasters say more abnormally warm weather is on the way later this summer. According to the CDC’s map, the regions hardest hit by heat illnesses are not always the ones seeing the highest temperatures. While temperatures have soared to 100 degrees and even beyond across much of the South and Southwest, the states seeing the highest numbers of heat-related ER visits are in the Northeast, Mid-Atlantic, Midwest, and Mountain west, where temperatures have been in the 80s and 90s. But the heat is much more unusual, especially in mid-June, for these locations, trending well above historical averages. On Saturday, for example, when the heat was reaching a climax in the northeast and mid-Atlantic regions, hospitals in more than two dozen states across six regions reported “extremely high” rates of heat-related emergencies despite temperatures hovering in that lower range. The CDC defines “extremely high” as being in the top 5% of busiest days for heat-related illnesses over the last five years, from 2018 through 2023. CDC health scientist Claudia Brown says that’s because built environments in those areas aren’t designed to deal with heat and people’s bodies aren’t as used to handling high temperatures. “So in these more northern regions, for example, there tends to be less prevalence of air conditioning in the homes,” said Brown, who works in the Climate and Health Program at the CDC’s National Center for Environmental Health. “So you may not have as high of temperatures as you have in, say, Arizona, but you have a higher health impact because they don’t have, necessarily, the infrastructure in place to deal with that heat.”