The sun beams down on a lifeguard while she watches over a beach at Lake Harriet during an extreme heat warning, Monday, July 13, 2026, in Minneapolis. (AP Photo/Ellen Schmidt)

2026-07-26T16:07:12Z

Tens of millions of people are under extreme heat warnings across central and southern parts of the United States on Sunday as high temperatures and severe humidity grip large swaths of the country for a second straight day.

Heat indices exceeding 105 degrees Fahrenheit (40.5 Celsius) were forecast from Memphis to Montana to Las Vegas. Parts of the southwest could see temperatures as high as 120 degrees Fahrenheit (49 C), according to the National Weather Service.

The sweltering conditions are the result of yet another heat dome — a phenomenon in which atmospheric conditions trap heat, accentuating and prolonging already high temperatures.

For much of the country, the brutal heat isn’t expected to let up soon.

“It looks like it is going to be pretty much stationary in that position as we go through the week,” Bob Oravec, an NWS meteorologist said Saturday.

There might be some relief in the central U.S. toward next weekend, but even that could be temporary, Oravec said.

Authorities warned that children and older adults, along with people with certain medical conditions, are especially at risk of serious reactions including heat stroke. Experts recommend seeking out air conditioning or a cooling center, make sure to drink enough water and limit time under the direct sun.

The continental U.S. endured the second-hottest first half of the year on record in 2026, according tracking of average temperatures by the National Centers for Environmental Information.