PHOENIX — The first day of summer brought some of the worst heat the Southwest United States has seen in years, forcing flights to be canceled, straining the power grid and making life miserable for workers toiling in temperatures that reached 120 degrees in some desert cities.
Arizona is seeing some of the most dramatic temperatures Tuesday, but the heat wave is being felt across Nevada and California, too.
It comes as researchers say deadly heat waves like this one are going to grow more frequent.
It reached 119 degrees in Phoenix, the fourth highest recorded temperature in the city’s history, and 126 in Death Valley. Palm Springs, Calif., hit 120, still two degrees lower than a June four years ago. The operator of California’s power grid called on people to conserve electricity during peak hours.
Workers at a construction site in a Phoenix suburb huddled under an excavator to find a sliver of a shade during a break. At another building site, men in hard hats and yellow vests labored and sweated in the heat and downed water to stay hydrated.
Project superintendent Tommy Russell says his company has held weekly safety meetings to prepare for the heat, and he will send all his workers home if it hits 120.
Las Vegas also was baking. Out-of-town visitors tried to stay inside air-conditioned casinos as much as possible, and some tourists lugged packs of bottled water around the Strip. Others went to a bar where the temperature is set at 23 degrees, and glasses, walls and seats are sculpted from ice.
Tonya and Lavonda Williams traveled to Sin City from Orlando, Florida, to get out of town and see the Backstreet Boys in concert.
‘‘This is like the oven door is open,’’ Lavonda Williams said as the sisters walked into The Palazzo casino-resort.
Landscaper Juan Guadalupe scaled a spindly palm tree more than 50 feet tall in Phoenix, using a chain saw to hack the branches. He didn’t mind being tethered to a tall tree because he occasionally catches a cool breeze.
‘‘Down here, it’s hot,’’ Guadalupe said.
In addition to grounding more than 40 flights of smaller planes, airlines have been taking other measures on larger jets to reduce their weight. American Airlines spokesman Ross Feinstein said the carrier began limiting sales on some flights to prevent the planes from exceeding maximum weight for safe takeoff in the hot conditions.
Meanwhile, the heat and dry conditions have fed wildfires. One fire destroyed a home and damaged another while forcing hundreds of people to evacuate Brian Head, a Utah ski town. The fire was started by somebody using a torch to kill weeds, Governor Gary Herbert said Tuesday.
Wildfires have also hit California, where a blaze in the San Bernardino Mountains east of Los Angeles is 10 percent contained, and northern Nevada, where firefighters are battling a trio of wildland blazes.
