 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. It's a new daily heat risk forecast from the National Weather Service. It factors in how long it has been hot and where someone lives since a 90-degree day hits differently in Wisconsin than in Arizona. Dr. Narang has worked in the emergency department in Phoenix for 11 years. He says the tracker data reflects his own experience.