Pack or skip
Thermal underwear for Chicago in January
Verdict
Pack it
Lows around 17°F — thermals are the difference between a walk and a march.
Why
Chicago in January averages highs of 32°F, lows of 17°F, 11 rainy days.
That climate means thermal underwear earns its space in the bag. Lows around 17°F — thermals are the difference between a walk and a march.