Dangerous heat forecast across the central and eastern United States through the July 4 weekend

A dangerous heatwave is forecast to intensify across much of the central and eastern United States starting Sunday, June 28, 2026. High temperatures up to 38°C (100°F) and heat index values reaching 38 to 43°C (100 to 110°F), locally as high as 46°C (115°F), through the Independence Day holiday weekend. Source