LAS VEGAS : Used to shrugging off the heat, Las Vegas residents are now eyeing the thermometer as the desert city is on track Wednesday to set a record for the most consecutive days over 115 degrees Fahrenheit (46.1 Celsius) amid a lingering hot spell that will continue scorching much of the U.S. into the weekend.

On Tuesday, Las Vegas flirted again with the all-time temperature record of 120 F (48.8 C) reached on Sunday, but settled for a new daily mark of 119 F (48.3 C) that smashed the old one of 116 F (46.6 C) set for the date in 2021. Forecasters say the city will likely hit a record fifth straight day above 115 F (46.1 C) on Wednesday.

Even by desert standards, the prolonged baking that Nevada’s largest city is experiencing is nearly unprecedented.

“This is the most extreme heat wave in the history of record-keeping in Las Vegas since 1937,” said meteorologist John Adair, a veteran of three decades at the National Weather Service office in southern Nevada.

Tuesday’s high temperature tied the mark of four straight days above 115 F (46.1 C) set in July 2005. And Adair said the record could be extended through Friday.

Alyse Sobosan said this July has been the hottest in the 15 years she has lived in Las Vegas. A counselor at a charter school that’s on summer break, Sobosan said she doesn’t step outside during the day if she can help it and waits until 9 p.m. or later to walk her dogs.

“It’s oppressively hot,” she said. “It’s like you can’t really live your life.”  It’s also dangerously hot, health officials have emphasized.

“Even people of average age who are seemingly healthy can suffer heat illness when it’s so hot its hard for your body to cool down,” said Alexis Brignola, an epidemiologist at the Southern Nevada Health District.

The searing heat wave gripping large parts of the U.S. also led to record daily high temperatures in Oregon, where it is suspected to have caused six deaths, the state medical examiner’s office said Tuesday. More than 161 million people around the U.S. were under heat alerts Tuesday, especially in Western states.

Dozens of locations across the West tied or broke previous heat records over the weekend and are expected to keep doing so all week.

The heat was blamed for a motorcyclist’s death over the weekend in Death Valley National Park. At Death Valley on Tuesday, tourists queued for photos in front of a giant thermometer that was reading 120 F (48.9 C).

Simon Pell and Lisa Gregory from London left their air-conditioned RV to experience a mid-day blast of heat that would be unthinkable back home.

“I don’t need a thermometer to tell me that it’s hot,” Pell said. “You hear about it in stories and wildlife documentaries. But just for me, I wanted to experience what it would feel like. … It’s an incredible experience.”

Death Valley is considered one of the most extreme environments in the world. The hottest temperature ever officially recorded on Earth was 134 F (56.67 C) in July 1913 in Death Valley, though some experts dispute that measurement and say the real record was 130 F (54.4 C), recorded there in July 2021.

Record highs for the date were also hit Tuesday in parts of Oregon and Washington, with Portland reaching 103 F (39.4 C) and Salem and Eugene hitting 105 F (40.5 C). Triple digit temperatures were also recorded in Idaho.

Phoenix, which has averaged the hottest temperature ever for the first eight days of July in records dating to 1885, tied the daily record Tuesday of 116 F (46.6) set in 1958.

The high Tuesday of 106 F (41.1 C) in Reno, Nevada, broke the daily record of 104 F (40 C) last tied in 2017 and extended to four days the longest streak ever of 105 F (40.5 C) or higher. Before this week, at an elevation of 4,500 feet (1,372 meters), the city had never been that hot for more than two consecutive days in records dating to 1888.

The U.S. heat wave came as the global temperature in June was a record warm for the 13th straight month and marked the 12th straight month that the world was 1.5 degrees Celsius (2.7 degrees Fahrenheit) warmer than pre-industrial times, the European climate service Copernicus said.

Most of this heat, trapped by human-caused climate change, is from long-term warming from greenhouse gases emitted by the burning of coal, oil and natural gas, scientists say.

In Las Vegas, hotels and casinos keep their visitors cool with massive AC units. But for homeless residents and others without access to safe environments, officials have set up emergency cooling centers at community centers across southern Nevada.

Firefighters in Henderson, Nevada, last week became the first in the region to deploy what city spokesperson Madeleine Skains called “polar pods” used to cool a person exhibiting symptoms of heat stroke or a related medical emergency.

Skains said four vehicles, including battalion chiefs in the city of more than 330,000 residents have the devices that are similar to units first put into use a month ago in Phoenix. They can be filled with water and ice to immerse a medical patient in cold water on the way to a hospital.

Extreme heat and a longstanding drought in the West has also dried out vegetation that fuels wildfires.

A new blaze in Oregon, dubbed the Larch Creek Fire, quickly grew to more than 5 square miles (12 square kilometers) Tuesday evening as flames tore through grassland in Wasco County. Evacuations were ordered for remote homes about 15 miles (24 kilometers) south of The Dalles.

 In California, firefighters were battling least 18 wildfires Tuesday, including a 42-square-mile (109-square-kilometer) blaze that prompted evacuation orders for about 200 residences in the mountains of Santa Barbara County.

The Lake Fire was only 16% contained, and forecasters warned of a “volatile combination” of high heat, low humidity and northwest winds developing late in the day.

Northeast of Los Angeles, the 2-square-mile (5-square-kilometer) Vista Fire chewed through trees in the San Bernardino National Forest and sent up a huge plume of smoke visible across the region.

The National Weather Service said it was extending the excessive heat warnings across most of the Southwest U.S. through Saturday morning.  “It’s not over yet,” the service in Reno said.