Extreme heat grips U.S. as 42 million under alerts and temps surge to near 119°F

A massive heat dome is enveloping much of the central and eastern U.S., with more than 42 million people under heat alerts. Temperatures in some locations climb toward 100–120°F, including a 119°F reading near Tecopa, California, and heat index values around 120°F in parts of the Southwest. The National Weather Service warns the heat is dangerous and urges hydration and cooling, while relief is expected by the end of the week as a cold front moves in.