PHOENIX — A blazing heat wave expected to send the mercury soaring to nearly 120 degrees in Phoenix and Las Vegas over the weekend settled across the West on Friday, threatening to ground airliners and raising fears that pets will get burned on the scalding pavement.
The heat was so punishing that rangers took up positions at trailheads at Lake Mead in Nevada to persuade people not to hike. Zookeepers in Phoenix hosed down the elephants and fed tigers frozen fish snacks.
And tourists at California’s Death Valley took photos of the harsh landscape and a thermometer that read 121.
The mercury there was expected to reach nearly 130 through the weekend — just short of the 134-degree reading from a century ago that stands as the highest temperature ever recorded on Earth.
“You have to take a picture of something like this. Otherwise no one will believe you,” said Laura McAlpine, visiting Death Valley from Scotland on Friday.
The heat is not expected to break until Monday or Tuesday.
The scorching weather presented problems for airlines because high temperatures can make it more difficult for planes to take off. Hot air reduces lift and also can diminish engine performance. Planes taking off in the heat may need longer runways or may have to shed weight by carrying less fuel or cargo. Smaller jets and propeller planes are more likely to be affected than bigger airliners that are better equipped for extreme temperatures.
The National Weather Service said Phoenix reached 116 on Friday, two degrees short of the expected high, in part because of a light layer of smoke from wildfires in neighboring New Mexico that shielded the blazing sun. Las Vegas still was expecting near record highs over the weekend approaching 116 degrees while Phoenix was forecast to hit nearly 120. The record in Phoenix is 122.
Temperatures are also expected to soar across Utah and into Wyoming and Idaho, with triple-digit heat forecast for the Boise area. Cities in Washington state that are better known for cool, rainy weather should break the 90s next week.
“This is the hottest time of the year, but the temperatures that we’ll be looking at for Friday through Sunday, they’ll be toward the top,” said National Weather Service meteorologist Mark O’Malley. “It’s going to be baking hot across much of the entire West.”
The heat is the result of a high-pressure system brought on by a shift in the jet stream, the high-altitude air current that dictates weather patterns. The jet stream has been more erratic in the past few years.
Health officials warned people to be extremely careful when venturing outdoors. The risks include not only dehydration and heat stroke but burns from the concrete and asphalt. Dogs can suffer burns and blisters on their paws by walking on scorching pavement.
“You will see people who go out walking with their dog at noon or in the middle of the day and don’t bring enough water and it gets tragic pretty quickly,” said Bretta Nelson, spokeswoman for the Arizona Humane Society. “You just don’t want to find out the hard way.”
Cooling stations were set up to shelter the homeless as well as elderly people who can’t afford to run their air conditioners.