More than 37 million Americans are under heat advisories across the U.S., according to the National Weather Service. Here's the hardest hit areas.

Beginning Saturday, Chicagoans can expect intense heat compounded by muggy humidity for the next several days. The National Weather Service has declared an extreme heat warning in Cook County from ...

A punishing heat wave in the Southwest is set to spread east in the coming days, with temperatures over 90 degrees Fahrenheit expected in the Northeast and possible record highs in parts of New ...