Millions in the Southwest face extreme heat warnings, with Phoenix experiencing dangerously high temperatures. Northern Alaska, unaccustomed to such heat, is under advisories due to potential heat-related illnesses. The eastern U.S. is seeing relief with cooler temperatures but faces risks of heavy rainfall and flash flooding. Health risks remain significant, as over 165 million Americans were exposed to major or extreme heat-related health issues during the peak of the heat wave. The shift westward may also exacerbate wildfire risks and poor air quality in the Rockies and High Plains.