The temperature poked its head all the way up to 14°C this morning and has otherwise held steady around 13°C since yesterday evening. That means it's a full 37°C warmer—yes, the difference between freezing and typical human body temperature—than January 1st (-23°C).
Unfortunately, a cold front will bring Canadian cold through Chicago this evening, dropping the temperature 20°C overnight and another 5°C (to around -14°C) by Saturday night.
So picking the right coat this morning was more challenging than one might think.
And this, by the way, is a predicted result of anthropogenic climate change: weather extremes, from unseasonably warm to unseasonably cold, in the winter—but only in some places. Because right now, the northern hemisphere is way, way warmer than normal: