The worst of the latest blast of bitterly cold air was at its strongest Monday night into Tuesday morning, and residents are begging for spring. And thanks to widespread school cancelations, parents were forced to bring their kids to work or leave them at home alone.

"Dangerously cold temperatures will continue in the Midwest for the start of the work week with wind chills in the-20s,-30sand-40s," said weather.com meteorologist. "In Chicago, the low temperature Tuesday morning will rival the coldest reading we saw in early January. Some cities will threaten daily record lows on Tuesday morning."

In Chicago, temperatures had fallen below zero by Monday afternoon with wind chills in the negative double-digits.

"We had two (employees) call in because they couldn't come to work because of the school closings, and another called in sick," said Kristelle Brister, the manager of a Chicago Starbucks, who was forced to bring her 9-year-old son to work after the city shut down its 400,000-student school system for the day.

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The Cincinnati neighborhood of Mount Adams is shown blanketed in snow on Saturday, Jan. 25, 2014.

(AP Photo/Amanda Lee Myers)

Residents of Minnesota and Wisconsin faced similar if even somewhat more severe weather.

Wind chills in the minus 40s were expected in Minneapolis, while in Milwaukee the chill hit minus 23 by mid-afternoon. Elsewhere, wind chills of minus 18 were expected in Dayton, Ohio, minus 14 in Kansas City, Mo., and minus 3 in Louisville, Ky.

The chill Monday was enough to keep even the hardiest people off the streets, including the customers of the Hollywood Tan salon in the southwestern Illinois' community of Belleville.

"It's definitely a lot slower," said salon manager Kelly Benton, who wasn't expecting anything near the 100 tanners the salon sees on a typical day.

But the chill didn't keep crowds from Tiny Tots and Little Tykes Preschool and Child Care Center in West St. Paul, Minn., where the cold weather means a lot more jumping rope and riding around on scooters - anything to escape cabin fever and let kids burn off some energy.

"We're just trying to keep them busy, but it's definitely more of a challenge when you can't get outside," said ManaRae Schaan, the executive director.

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The brutally cold weather has brought a spike in business for GrubHub Seamless, a company that lets users order food online from restaurants and have the food delivered.

"Across the board, restaurant and delivery drivers are dealing with an influx of orders," Allie Mack, a spokeswoman for the company said in an email.

Not only that, but people seem to appreciate the drivers more, with Mack saying that during previous cold blasts this month, tipping was up by double digits in Detroit, Cleveland, Minneapolis and Chicago. And, for some reason, deliveries of buffalo chicken sandwiches jumped 37 percent.

"You figure people are probably being more generous to their drivers because their drivers are the ones braving the conditions while you're on your couch in your pajamas," Mack said.

Chicago cabdriver Kumar Patel said the cold translates into bigger tips for him too.

But the chill also seems to trigger some bad behavior as well, he said.

"They get in and they say they have to smoke because it's so cold," Patel said.

Still, he said, he can pick up a lot of fares in a short time. "They are going a block, sometimes only a half block," Patel said.

The frigid weather also sent runners inside to health clubs or into stores to buy treadmills.

"Treadmills and ellipticals are the No. 1 seller now that conditions are terrible," said Dave O'Malley, manager of Chicago Home Fitness.

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In Milwaukee, Michael Comerford, a 33-year-old barista, said Monday that he is making far fewer lattes than normal but expects the trend to reverse once the severe chill subsides.

"Once it gets warmer, like the single digits or teens, it feels like a heat wave so people come out again," he said.

It is the same for Brandon Kulosa, whose business is getting rid of critters that become dissatisfied with their homes and move into ours.

"They hunker down when it gets this cold," said Kulosa, co-owner of Animal Trackers Wildlife Co. in suburban Chicago.

Not only that, he said, but the ones that already have gotten into your attic seem to recognize they have it pretty good and should not draw attention to themselves and risk eviction.

"You could have a raccoon up in your attic just sleeping," said his partner, Tony Miltz. "They're not going anywhere."

Information from the Associated Press was used in this report

Brad Metzger skates on Mirror Lake on Monday, Jan. 27, 2014, in Cincinnati's Eden Park, where temperatures were expected to reach a high of 10 degrees. (AP Photo/Al Behrman)