UPDATE 1-Dozens of people succumb to heat as western U.S. bakes
(Adds details of people treated, cooling centers, latest temperatures, quotes)
By Brad Poole
TUCSON, Ariz., June 29 (Reuters) - Dozens of people were treated for heat-related symptoms and many towns and cities across the western United States took emergency steps to help residents cool off, as the region sweltered on Saturday in dangerous triple-digit temperatures.
Extreme heat enveloped most of California and Nevada and parts of southern Arizona as a large high-pressure system trapped hot air across the area, National Weather Service meteorologist Todd Lericos said.
"It involves pretty much the entire West Coast at this point," Lericos said, adding that the steamy conditions, which began in some areas on Thursday afternoon, would likely continue throughout the weekend and linger into next week.
In Los Angeles County, many people have been hospitalized or treated for dehydration, exhaustion and heat stroke, said Keith Mora, a spokesman for the Los Angeles County Fire Department.
At an outdoor concert in Las Vegas on Friday, 34 people were taken to the hospital after succumbing to the heat and another 170 suffered nausea and fatigue.
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 U.S. 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.
The scorching temperatures can cause potentially fatal heat stroke, Lericos said, noting that those with no air-conditioning or who must work outdoors were particularly at risk.
Temperatures by noon local time on Saturday had already reached 115 Fahrenheit (46 Celsius) in Phoenix, 109F (42C) in Tucson, Arizona, and 111F (43C) in Las Vegas and could hit highs of 120F (48C) or more, according to the National Weather Service.
The Running with the Devil Marathon scheduled for Saturday in the Mojave Desert outside of Las Vegas, which is designed so runners are "challenged to contend with high heat," was canceled.
Officials across California, Nevada, and Arizona set up air-conditioned "cooling centers" in community centers, homeless shelters and libraries, and warned residents to avoid prolonged exposure to the searing temperatures.
In Phoenix, emergency shelters are temporarily adding 150 beds in an effort to safeguard hundreds of homeless.
"Phoenix is a major city with a lot of concrete that tends to hold a lot of that heat in, so it's just like you're in a dry sauna," said Irene Agustin of the Central Arizona Shelter Services non-profit in Phoenix.
In Nevada, officials in Clark County, which includes Las Vegas, said they have installed 13 air-conditioned areas in community centers and homeless shelters, though the majority of them would be closed on Sunday.
In 2005, roughly 17 people died during an equivalent heat wave over a 10-day period in the Las Vegas area.
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.
In Southern California's Death Valley, one of the hottest places on earth, temperatures could soar on Saturday to 128F (53C), close to the record set on this day in 1994. By noon the temperature was 114F (45C).
Dan Kail, 67, was on vacation in Las Vegas when he heard about the triple-digit temperature readings in Death Valley.
He hopped in a rental car and made the 2-1/2 hour drive, yearning to feel air that he later described as a "blast furnace."
"I've never experienced that kind of heat," said Kail, who owns parking lots in Pittsburgh. "It almost burns you as it blows by you. It's amazing."
Tucson mechanic Rick Riesgo, 55, was finishing a round of golf on Saturday morning with the temperature already well over 100F (38C).
"I just make sure I drink a lot of water ... until 10 a.m., then I drink a lot of beer," he said smiling as he headed for the clubhouse to cool off.
The tigers at the Phoenix Zoo were fed frozen trout, the monkeys are getting frozen yogurt, and lions and other animals can lounge on artificial rocks and slabs of concrete cooled by piped water, said Linda Hardwick, a zoo spokeswoman.
While most people were retreating inside air-conditioned buildings, an organizer of the Las Vegas Bikini Invitational beauty pageant on Sunday said contestants would brave the heat for the outdoor event.
"We have a beautiful pool suite set up for the contestants to relax in between rounds," said Roni Taylor-Parsons, an event spokeswoman. "We will be serving frozen fruit to all cabana guests as well as having a lot of water and frozen Popsicles on hand." (Reporting by Brad Poole; Writing by Eric Johnson; Additional reporting by Timothy Pratt in Las Vegas, and Marty Graham in San Diego; Editing by Greg McCune and Eric Beech)