A heat dome is baking the United States. Here’s why that’s so dangerous
Our bodies aren’t used to summer temperatures yet, raising the risk of heat-related illnesses

A man is attended to after fainting in the heat outside the U.S. Supreme Court in Washington, D.C. on June 20. Heat wave temperatures across the Midwest and Northeast are hovering around 38° Celsius (100° Fahrenheit) in many places.
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