As of June 22, 2026, the National Weather Service has placed 141 million Americans under major or extreme heat risk — the peak day of a multi-day heat siege stretching from the Ohio Valley and the eastern Great Lakes to the interior South and the East Coast. Triple-digit heat index values are expected across significant portions of the region. Areas under Excessive Heat Warnings may feel like 110°F or hotter when humidity is factored in.
This is not an abstract weather event. Heat is the deadliest form of extreme weather in the United States, killing more Americans each year than hurricanes, tornadoes, and floods combined. More than 21,000 deaths between 1999 and 2023 were officially recorded as heat-related, and public health researchers consistently note that official counts underestimate the true toll, as many heat-exacerbated deaths from cardiovascular and respiratory disease never appear in heat-related mortality statistics.
