By game time, it’s about 103 degrees Fahrenheit (39.4 degrees Celsius) on this Labor Day afternoon in downtown Phoenix. Business is brisk.

“Two for five, but it’s eight inside!” shouts another vendor, hawking water bottles. “Plus, they’re having some problems with the air conditioning in there.”

It’s always hot this time of year in central Arizona, but 2024 is proving to be an endless summer with especially high temperatures in Phoenix. On Tuesday, the city hit its 100th straight day with at least 100 degree temperatures. That’s long since shattered the record of 76 days in a row set back in 1993, according to data from the National Weather Service.

“That is definitely an eye-catching number,” NWS meteorologist Sean Benedict said.

Scientists say climate change caused by human activities is dialing up the thermostat around the world and increasing the odds of dangerous temperatures. That is because the driver of global warming — the release of greenhouse gases from the burning of fuels like oil, gas and coal — continues all but unabated. Extreme weather events like heat waves, wildfires, intense storms, and prolonged droughts will continue, according to researchers.

The temperature hit 102 F (38.9 C) in Phoenix on May 27 and has made it to triple digits every day since.

Benedict said that long streaks of desert heat usually are broken up by rain, but the monsoon hasn’t delivered much. The persistent heat also got an early start, with the triple-digit days already piling up in May.

It doesn’t look like a break is coming any time soon.

Unseasonably high temperatures are expected this week across the western U.S., with an excessive heat warning forecast for Wednesday through Friday in Arizona cities including Phoenix and Lake Havasu City, as well as Las Vegas and other parts of Nevada, including Laughlin and Pahrump.

The California desert communities of Palm Springs, Twentynine Palms, Needles and Barstow will also heat up, with highs of up to 118 F (47.7 C) in Death Valley’s Furnace Creek expected at week’s end.

Public health officials in Arizona’s Maricopa County — where Phoenix is located, the hottest metro area in the U.S. — say that as of Aug. 24 there had been 150 heat-related deaths confirmed so far this year, with another 443 under investigation. There were 645 heat-related deaths last year in the county of some 4.5 million people.

Pretty much any way the data is parsed, 2024 marks another record-breaking summer of heat in Phoenix. It’s been the hottest meteorological summer, which includes the months June, July and August. And it’s the same story throughout the western U.S. with several locations in California, Nevada, Arizona, Utah and New Mexico setting records or coming close.

In Nevada’s Clark County, which includes Las Vegas, there have been 181 confirmed heat-related deaths so far this year. But the death toll is likely far greater, officials said, because it takes the Clark County coroner’s office up to three months to investigate the cause of death in about 90% of its cases.

In 2023, there were 294 deaths in Clark County where heat played a role and more than 2,200 heat-related emergency room visits, according to data maintained by the Southern Nevada Health District.

Across California, red flag warnings for increased wildfire risk were issued.

A wildfire that has forced hundreds of people to flee their homes in Northern California near the Nevada line continued to threaten more than 200 structures Tuesday night in a remote mountain community in the Sierra about 50 miles (80 kilometers) north of Lake Tahoe, the U.S. Forest Service said.

No serious injuries have been reported since the Bear Fire broke out Monday. But more than 500 residents remained under evacuation orders Tuesday night and warnings were expanded around the blaze that has burned through about 3 square miles (7.8 square kilometers) of timber and brush and sent up a plume of smoke visible about 25 miles (40 kilometers) away in Reno, Nevada.

Cooling centers were set up across Los Angeles County, where officials urged residents to check on neighbors who are elderly, unwell or otherwise vulnerable amid soaring temperatures. “Hot days aren’t just uncomfortable — they can be dangerous,” said LA County Health Officer Muntu Davis.

There’s no respite from the heat for outdoor vendors. It’s the same story for plenty of other people in the Phoenix area, particularly construction workers and landscapers.

Ferguson’s job outside in downtown Phoenix is a hot one. The concrete and asphalt all over downtown makes it feel even hotter, with the heat radiating through the streets as more than 40,000 fans gather for a game between the Los Angeles Dodgers and Diamondbacks.

“Lots of SPF shirts and ice-cold water,” Ferguson said, about coping with the heat. “That’s the only way to get through it.”

Chase Field can be air-conditioned and has a retractable roof that is closed for most games during the middle of summer, which is obviously good for fans and players. But keeping the giant stadium cool in the summer is sometimes tricky, and players have occasionally commented about how surprisingly stuffy it gets inside.

Ramiro Lopez has been doing landscaping in suburban Phoenix for five years and says each summer feels hotter than the last. Between jobs, he takes breaks in his air-conditioned truck to stave off the heat, but the past three months have been a grind.

“I’ve learned to drink lots of sports drinks and make sure I’m done by 1 p.m.,” Lopez said. “Otherwise, it’s just too much.”

In Phoenix, there have been 37 nights this summer that didn’t cool off below 90 F ( 32.2 C), another record.

There have also been 54 days of 110 degree temperatures, which is just one day away from breaking the record of 55 days last year. That number could be broken later this week. The heat is tough for everyone, but is particularly difficult for low-income areas.

“Not being able to cool off at night can affect people’s health because heat can accumulate in the body,” Arizona State University climatologist Erinanne Saffell wrote in an email response. “Folks should make sure to stay cool and hydrate.”