A record-challenging heat dome is about to bake the West this weekend

A record-challenging heat dome will bring extreme temperatures to the western U.S. and Canada, with over 40 million people under heat alerts. Death Valley is forecast to reach 126°F, while cities like Billings and Salt Lake City may break their all-time heat records. The heat dome's intensity is linked to human-caused climate change, which increases the likelihood and severity of such events.