CHICAGO (CBS) — Dangerously cold weather was moving into the Chicago area on Tuesday, with lows expected to dip into the single digits overnight, and to plunge below zero early Thursday.

A massive high-pressure front that’s pushing down from Canada is bringing incredibly cold temperatures.

Highs on Tuesday were expected to be only around 20 degrees, with a low around 5 degrees by midnight.

Temperatures won’t be much better on Wednesday, with a high around 17, and a low around 2 below zero by early Thursday, and only rising to a high of around 5 later that day.

Chicago’s lakefront trail was more like Desolation Boulevard on Tuesday. The 18-mile path normally is crowded with people, but on Tuesday only hardcore exercise buffs were out.

Kenneth Hill was wearing three layers of socks on his hands and five layers on his chest and arms as he went for a ride on his bike.

“How are you going to get cold with five layers?” he said.

Coverage is the name of the game when you’re out in this kind of cold for any length of time. Brian O’Donnell found that out the hard way when he made the mistake of wearing ankle socks before going for a run, leaving a couple inches of his legs exposed to the single-digit wind chills.

“They’re a little bit rough,” he said.

So, on Wednesday, there won’t be any ankle socks, and on Thursday there might not be any running, given the wind chill could be 20 below zero.

“Thursday, I’m really debating whether or not I’m going to run,” he said.

However, Jerome McDonnell will be riding his bike to his job as midday host at WBEZ the rest of the week, no matter how cold it gets.

“I remember those 13 degree below days, and I thought ‘Oh, I don’t know if I’ll be able to make it,’ and of course I could make it. It was not a problem,” he said.

Hill looked more than able to handle the cold when he rode by, but his bike chain apparently could not. It broke as he was riding, but he said he wasn’t feeling the least bit cold as he walked his bike along the path.

“I’m just from Chicago, this is what Chicago people do,” he said.

Commuters at the Roosevelt stop on the CTA Green and Orange lines said, despite an unusually warm winter last year, when Chicago had only four days with temperatures below zero, the coming cold is something they have come to expect.

“To me, it’s not cold yet. You know, this is Chicago, the Windy City. Now, tomorrow and Thursday might be pretty cold when they say 12 degrees, 7 degrees, but right now it’s not that cold,” Osmond Wicks said.

Mayor Rahm Emanuel has asked Chicagoans to keep an eye out for those in need as temperatures begin to plummet these next few days.

“If you have a senior, or somebody who’s physically disabled or not well in your neighborhood and community, I ask you as a good resident to check in on them,” he said.

The end of the week should bring a small bit of relief from the bitter cold, with highs back up in the low 20s on Friday, and the low 30s on Saturday, before an even colder blast of Arctic air on Sunday, when the high is expected to be around 1 degree, with a low of 10 below zero by Monday morning.