In the Southwest, sweltering heat bared down on Utah’s Salt Lake City, tying its highest temperature ever recorded.
In a tweet, the local National Weather Service (NWS) wrote that the high tied with the city’s previous record set in 1974.
The city of Denver, Colo., reached a high of 101 degrees Fahrenheit, breaking the old record of 97 degrees Fahrenheit.
In Death Valley, AccuWeather said temperatures could come close to 134 degrees Fahrenheit – the highest air temperature recorded on Earth – in the next couple of days.
Nearby, Nevada’s Las Vegas is forecast to reach 115 degrees Fahrenheit.
The NWS Weather Prediction Center advised Wednesday that residents stay inside in air-conditioned buildings, stay hydrated and take “frequent breaks if engaging in outdoor activities.”
“Dozens (possibly hundreds) of daily record high maximum and minimum temperatures are likely to be set over the next few days in California, the Intermountain West, Desert Southwest, Rockies, and Central/Northern Plains,” it warned.
The Associated Press contributed to this report.