Dozens of people in the U.S. states west was treated for exhaustion and dehydration as the emergence of a heat wave in the region.
More than 34 people were taken to hospital after attending an outdoor concert in Las Vegas, Nevada, local officials said.
They also say that an elderly resident was found dead in a house without air conditioning.
The man was suffering from a medical problem, but the condition is believed to have been exacerbated by the heat wave, said by the Associated Press.
While in Los Angeles, California, a number of people are also reported to have been treated for overheating and dehydration.
Shelters for the homeless in Phoenix, Arizona, adding an extra bed because the temperature in the city is expected to reach 50 degrees Celsius.
The National Weather Service earlier issued a heat wave warning for some areas may take until Monday (01/07) morning.
added personnel
Temperatures in Death Valley in California desert is estimated at 54 degrees Celsius. The highest temperature ever felt on Earth is 56.7 centigrade, ever recorded there on July 10, 1913.
Heat wave came after the area experienced the driest winters in history. There are fears the heat wave will trigger wildfires, says the BBC's David Willis in Los Angeles.
Rescue teams from the U.S. Border Patrol has added additional personnel this weekend in anticipation of growing threat of exhaustion and dehydration for those trying to cross the US-Mexico border illegally on foot.
At least seven migrants found dead in the Arizona desert last week at a lower temperature. Border officials in Tucson, Arizona, rescued more than 170 people suffering from the heat during the thirty-day period in May and June.