SYDNEY, Australia — At a dried-up waterhole in Australia’s far north, wild horses were found dead or dying. In cities in the southeast, power outages darkened traffic lights and shopping malls, and office workers and commuters were left exhausted and wilted.
On the island of Tasmania, more than 50 wildfires were burning, and farmers were bracing for more. And in Elizabeth North, a town north of Adelaide, the Red Lion Hotel promised free beer if the temperature reached 45 degrees Celsius (113 Fahrenheit) — and then had to deliver.
“I got three marriage proposals, the problem was all of them were dudes over 60 years old,” said Stephen Firth, the pub’s manager.
Australia — again — is in the midst of one of its hottest summers on record. In the southeast, where most people live, aging coal-powered plants struggled to cope with demand on Friday, with more than 160,000 households temporarily losing power.
In Melbourne, tram routes were cut back to save power, public swimming pools were overwhelmed and people who could get to air conditioning did so.
“I think this is the hottest day I’ve ever experienced in my life,” Ikumi Cooray, 25, said Friday, waiting for a tram in Melbourne as a popsicle melted in her hand.
It wasn’t — at least, not if Ms. Cooray was in Melbourne in 2009, when the city hit its current record of 46.2 degrees Celsius. Friday’s temperatures reached a mere 42.4 degrees, but that was bad enough. The day before, the heat had been so intense that Petra Kvitova’s semifinal against Danielle Collins at the Australian Open was halted so the roof of Rod Laver Arena could be closed.
Adelaide, to the northwest, did break a record on Thursday — an 80-year-old one — reaching 46.2 degrees Celsius, or 114 Fahrenheit.
Mr. Firth, the pub manager, said everyone at the Red Lion behaved, though he expressed concern about whether he could keep giving away beer going through the heat wave. “We might be breaking liquor laws if we give out that much free beer, but we can’t control the temperature,” he said.
In Melbourne, few people were venturing outside on Friday, and business at cafes and restaurants was slow.
“We have been dead today,” said Nicole Smith, who works at a cafe in the suburb of Collingwood. “Everyone’s obviously been ordering Uber Eats and doesn’t want to leave the office.”
The power in the cafe had repeatedly gone out on Thursday, she said. “All our fridges kept turning off.”
“I just feel sick,” said her co-worker Anwesha Sinha, who had brought an umbrella to shield herself from the sun on her walk home. Ms. Sinha, an immigrant from India, said she was used to humid heat but found the dry heat hard to cope with. She said she had gotten a nose bleed. “I walked 300 meters today and I felt sick,” she said.
There were graver concerns in the southern island state of Tasmania, where there were 56 active wildfires as of Friday. No deaths or injuries have been reported, but there have been evacuations, and temperatures have continued to climb.
“People have not been sleeping, they’ve been snapping at each other,” said David Killick, a hobby farmer in Judbury, a town about 35 miles south of the city of Hobart. On Friday, he and his wife moved their dog and three horses off their stretch of farmland.
“Every Tasmanian is urged to have a fire plan, and we live in a relatively remote bush setting, so you have two choices: you either stay and fight the fire or you leave early,” said Mr. Killick, who also writes for the Hobart Mercury newspaper.
“There wasn’t an active fire near us, but when you live on a hilltop at the end of a dead-end street, you don’t want to be there when a fire starts,” he said. “We took some clothes, our photo albums and that’s about it. Shut the gate behind us and hope for the best.”
Tasmania is usually a more temperate place. Mr. Killick said visitors from Queensland, home to Australia’s Gold Coast, would typically come in the summertime to escape the heat.
In Australia’s Northern Territory, Aboriginal rangers had to cull more than 50 wild horses after finding dozens dead or dying near a water hole that had dried up. More culls were being considered as the heat wave showed no sign of slowing, said Elke Wiesmann of the Central Land Council.
There have been other dramatic illustrations of the heat’s extremity. This month, fruit growers in South Australia reported that the pits in peaches and nectarines had gotten so hot that they burned the fruit from the inside. In November, an extreme heat wave killed more than 23,000 flying foxes, a type of bat, almost a third of the species in Australia.
Many parts of the country have banned all fires just ahead of the Australia Day holiday weekend, during which most people celebrate outdoors.
Almost all of Australia’s 10 warmest years on record have occurred since 2005, according to the government’s Bureau of Meteorology. The bureau says rainfall has been decreasing in the south and that there have been longer and more frequent marine heat waves.
“There has been a long-term increase in extreme fire weather, and in the length of the fire season, across large parts of Australia,” the bureau said in a recent report.
Australia’s heat waves, now an annual ordeal, have been expanding into areas that hadn’t normally experienced them before, said David Rissik, deputy director of the National Climate Change Adaptation Research Facility.
“The fact that we had bushfires in places that traditionally don’t burn, like rain forests, I think was really an eye-opener,” Dr. Rissik said. “I would say that people are still digesting what that means to them.”