Updated 12/12/13 – 10:34 a.m.

CHICAGO (CBS) — First came the snow, then the bitter cold. A brutally frigid blast of air overnight is gradually leaving the area, though temperatures will stay below freezing at least until Saturday.

Temperatures dipped to 3 below zero overnight at O’Hare, with wind chills of 15 below. Conditions were even worse in the western and southwestern suburbs.

In Rochelle, about 70 miles west of Chicago, the temperature dropped to as low as 13 below zero, with a -27 wind chill, according to the National Weather Service. The temperature also hit -13 in west suburban Aurora, with a wind chill as low as -29. The suburbs of Romeoville, Lansing, and West Chicago also saw wind chills lower than 20 below zero.

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A wind chill advisory was in effect overnight, but expired at 5 a.m. Thursday. The National Weather Service warned the extreme wind chill could result in frost bite or hypothermia if you don’t take precautions by staying indoors as much as possible; and wearing layers, including a hat and gloves, to cover your skin when outdoors.

Luckily, the subzero temperatures are gone for a while. Though you certainly can’t call it warm, the weather will be a lot less frigid the next several days, with an expected high of 23 on Thursday, 28 on Friday, and 32 on Saturday.

CBS 2’s Susanna Song reports, when it reaches the 20s sometime Thursday afternoon, it will certainly feel better than it did this morning. People who braved the cold to make it to work earlier might finally be able to shed a layer or two.

Their commute home will be a lot less frigid than the one to work.

Tina Dandridge said she typically walks one mile to work from the Metra station, but she squashed that idea Thursday morning, when temperatures were still only a few degrees above zero. Instead, she stood in a crowded CTA bus shelter to hop a bus to work, and luckily for them their bus was running on time, so they didn’t have to wait long.

“We just grin and bear it. That’s it,” she said.

Dandridge said it helped that so many people were huddled under the shelter, to provide some body heat.

“It’s nice. It’s not too bad, but this is the wintertime. That’s what happens,” she said.

Dressing fashionably took a back seat to dressing warmly.

“Just layers of clothing, keep you warm; long underwear, double. That’s pretty much it, hope for the best,” said fellow commuter Maurice Fitzgerald.

For morning commuters, it was all about keeping as much of their faces covered, and keeping their fingers in their pockets. If neither option was enough to avoid the bone-chilling cold, they ran.

Margo Crenshaw confessed she committed a big “no-no” when she left home Thursday morning, leaving without gloves, a hat, or a scarf. To make things worse, she couldn’t run to get to work, she had to wait for her bus.

“My daughter took everything out of my work bag this morning, and I didn’t know it until I was already on the bus,” she said. “She took it out, and put it on the couch. She was getting stuff out of my work bag, and left everything at home, and I didn’t know it until I was already outside.”

It was a hard lesson learned for Crenshaw: double check to see that you have all your winter accessories on you before you venture outside.

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