The cold weather sweeping the Plains wasn't cooling off work in the oil patch, which moves forward in all kinds of weather. But even hardened oilmen were taking note of the dangerous conditions that were expected to keep daily highs below zero until Sunday.
A powerful winter storm that slammed much of the nation kept intensifying Thursday, draping many communities in skin-stinging cold. The system dumped 1 to 2 feet of snow in parts of Minnesota and Wisconsin, forcing school closures and temporary power outages and delighting skiers who hit the slopes despite temperatures in the single digits.
The south-central U.S. braced for the next blow, expected to come Friday in the form of sleet and ice that could imperil millions unaccustomed to the treacherous combination of moisture and bitter cold.
In Montana, temperatures fell as low as minus 26 in Great Falls and minus 27 in Havre, both records. In parts of the Rockies and Northern Plains, wind made those conditions feel even colder.
The deep freeze, blamed on the jet stream's move southward, was expected to linger at least through the weekend.
With the mercury falls this low, the cold inflicts pain on exposed skin almost instantly, and water poured from a cup can freeze before hitting the ground.
Contact lenses begin sticking to eyeballs. Cars fail to start, and people begin longing for heavy foods. Pets refuse to go outside.
The Red Cross urged people to stay inside or layer up to guard against frostbite if they must go out. The agency also asked residents to check on neighbors, especially those who need special assistance or live alone.
Holiday events were called off. In Rapid City, S.D., officials concluded it was too cold for ice skating.
Oil patch workers endure by layering up beneath fire-retardant clothing and taking breaks in small heated shacks called "doghouses," which are often near rigs. Many companies also try to hire locals with at least five years of experience.
"If they've made it that long, they're probably going to stick around," said Larry Dokken, a veteran oilman whose consulting firm recruits workers for oil companies.
Hendershot has shared the advice of dreaming of warmer climes to fellow workers in years past. He said a few have taken it literally.
"Some have actually left and gone to that warm, happy place," he said.
Some workers gripe about the bone-numbing temperatures, he added. Many others take pride in withstanding it.
"This is what I love to do," said Craig Hovet, during a break from maintenance work on a well Wednesday near Mandaree. "The joke around here is: This kind of weather keeps out the riffraff."
North Dakota historically has conjured up images of a bleak, wind-swept and treeless wasteland. The perception was so great that one group a decade ago proposed changing the state's name by dropping "North" and leaving just "Dakota," to dispel the state's image of inhospitable winter weather.
That was before North Dakota's recent oil bonanza, which has brought swarms of people to the state in search of jobs and a fresh start. Now thousands of new oil wells have been punched though the prairie, generating billions of dollars and abundant work. It's a boom that doesn't pause for the weather.
"The pace probably slows during extreme blizzard conditions," said Ron Ness, president of the North Dakota Petroleum Council, an industry group that represents hundreds of oil-related companies. "And there are extra precautions on safety. But it's work that is not going to stop."
Hendershot was keeping close tabs on his crew Thursday, making sure they got plenty of breaks in vehicles and the heated work shacks.
One worker told him Thursday that it had gotten so cold that "it froze his soul."
"There is only a certain amount of time these guys can work in this, and some people get cold quicker than others," Hendershot said. "Everybody talks about how much money an oil worker is paid. They earn it."
Daryl Andersen, a North Dakota native and 30-year oilman who now runs a well-services company, recalled his grade-school history books that described how George Washington and his army suffered at Valley Forge.
"But we're colder here than they ever were," he said.
North Dakota's notorious cold isn't a deterrent for Dylan Grossman, a 23-year-old Alaska native who posted a Craigslist ad seeking a laborer's job in the oil fields. Grossman is currently in Florida, where he's struggled to find work. He said he intends to move to North Dakota soon and has asked his mother to mail him his warmest clothes.
"I've heard it's cold and flat in North Dakota," Grossman said. "I think I can layer for it."
Hovet, who grew up in North Dakota, has heard that before. He recalls four Texans walking off a job site after being in North Dakota for just one day last winter.
"It was about 5 above and sunny and really kind of a pretty day," Hovet said. "They got their truck stuck in a ditch, and their equipment got frozen up. They said, 'The heck with this. We're going back to Texas.'"