The extreme heat poses significant health risks, particularly for vulnerable groups such as older adults, children, outdoor workers, and those without air conditioning. Prolonged exposure can lead to dehydration, heat cramps, heat exhaustion, and potentially life-threatening heat stroke. The NWS has warned of 'major heat risk' in affected areas, with additional strain on power grids and hazardous conditions for outdoor activities, especially in desert regions like the Grand Canyon. The combination of high daytime temperatures and warm nights increases the cumulative stress on the body, heightening the risk of heat-related illnesses.