 Claudia Brown is a health scientist at the CDC. Last year, she says, the tracker showed huge heat impacts. Several days exceeded the highest recorded rates that those regions had ever seen. And that wasn't a one-off. We're seeing these trends occurring again this summer with the recent heat wave in the upper Midwest and the Northeast. She says the tracker shows that heat-related illness has increased over the past few years. It now also includes something the CDC hopes will keep people out of the ER—