When red-hot isn't enough: New government heat risk tool sets magenta as most dangerous level

U.S. health and weather officials are unveiling a new color-coded system to warn Americans about heat danger, and it will set magenta as the most dangerous level. The National Weather Service and the Centers for Disease Control and Prevention used Earth Day on Monday to explain the new online heat risk system. It combines meteorological and medical risk factors with a seven-day forecast that’s simplified and color-coded for a warming world of worsening heat waves. Magenta is the deadliest category. It's a step above red, which is also pretty bad. The difference is that red is a threat to people without adequate cooling and hydration, while magenta describes weather so hot that it threatens everyone. The five-color system is are based on heat, duration and health factors.