Heat dome blankets U.S. as 42 million face heat alerts, temps surge to 119°F

More than 42 million people are under heat alerts across the U.S. as a westward-shifting heat dome drives temperatures to as high as 119°F near Tecopa, California. The National Weather Service warns of dangerous heat across the Southwest through the weekend, with heat indices around 120°F in parts of the desert Southwest and Gulf Coast. About 2 million people are at the highest risk and 24 million at major risk, with health guidance urging hydration, cooling, and limited outdoor activity. Relief is expected by week’s end as a cold front lowers highs by 10–20 degrees.