(Reuters) - Scorching heat baked the western United States and Sunday's forecast offered no relief from the soaring temperatures that prompted health warnings and sent scores of people to the hospital with heat-related illness.
Cities in California, Nevada, Arizona, Idaho, Colorado, Utah and Texas all recorded temperatures over 100 degrees (38 Celsius) on Saturday.
Paramedics in Las Vegas, where the temperature hit 115 F (46 C), found an elderly man dead in his un-air-conditioned apartment on Saturday. The man had prior medical issues and "either the heat got to him or the medical condition was aggravated by the heat," Fire-Rescue spokesman Tim Szymanski said.
Scores of other people were treated for heat-related symptoms, including a man who pulled off a Nevada highway and called 911 to say he felt ill after driving for several hours without air-conditioning. He was hospitalized in serious condition with heat stroke, Szymanski said.
Cities and towns across the western United States opened air-conditioned "cooling centers" in community centers, homeless shelters and libraries, and warned residents to avoid prolonged exposure to the searing temperatures.
A large and stagnant high-pressure system trapped the hot air, tying or topping temperature records that soared well above 100 degrees.
"Daytime highs will yet again dangerously soar well past the century mark and overnight lows will barely drop into the seventies and eighties," the National Weather Service said on Sunday.
"Triple-digit temperatures will expand north through the Intermountain West and all the way to the Canadian border."
In Los Angeles County, many people have been hospitalized or treated for dehydration, exhaustion and heat stroke, a fire department spokesman said.
There were fears that migrants attempting to cross into the United States from Mexico would die in the desert. More border agents were added on the American side, said Brent Cagen, a spokesman for the Tucson sector of the U.S. Border Patrol.
At least three people, maybe more, who attempted to illegally cross the border into Arizona were found dead this week, likely succumbing to the heat, Cagen said.
Firefighters worry about dry conditions, which have ignited several major brush fires across the region recently, and about more blazes ignited by wayward fireworks launched from backyards to commemorate the Fourth of July holiday.
(Reporting by Jane Sutton in Miami, Brad Poole in Tucson, Timothy Pratt in Las Vegas and Marty Graham in San Diego; Editing by Doina Chiacu)