Heat alerts cover 58 million people as western U.S. temperatures peak

Roughly 58 million people across the United States were under severe weather alerts on Sunday as a heat dome reached its peak over the western part of the country. In Billings, Montana, temperatures reached a record high of 110 degrees. Extreme warmth was also recorded across the Great Basin, the Rockies and sections of the desert Southwest.

Temperature records and warnings Salt Lake City reached an all-time high of 109 degrees on Sunday, according to the National Weather Service. The previous record of 107 degrees had been broken in 1960, 2002, 2021 and twice in 2022. Most of Utah remained under an extreme heat warning scheduled to stay in place through Tuesday morning.

Dickinson, North Dakota, recorded 105 degrees, breaking its previous record of 104 set in 2006.

Fire activity and other weather In California, the Summit Fire in the Antelope Valley burned nearly 3,000 acres and forced evacuations outside Los Angeles. The Los Angeles County Fire Department reported the blaze was 31 percent contained as of Sunday evening.

Two wildfires started Sunday in Colorado's high country while crews continued fighting the Aspen Acres Fire, which had burned more than 850 structures. In Louisiana, thunderstorms dropped several inches of rain on New Orleans, creating knee-high flooding.

In Philadelphia, microbursts with gusts up to 70 miles per hour struck neighborhoods on Saturday. The mayor signed a Declaration of Disaster Emergency on Sunday. In Missouri, rescue crews airlifted more than 200 people from a children's camp after 6 to 12 inches of rain caused historic flash flooding.