Right now, Chicago is around typical late-December winter cold, with temperatures roughly in the mid 20s to low 30s Fahrenheit (about −4-4−4 to 0 degrees Celsius), and it can feel colder with wind chill.

Quick Scoop

  • Normal December 31 temperatures in Chicago are about 33 °F for a high and 21 °F for a low, so freezing or below is very common this time of year.
  • Current forecasts for late December 2025 show conditions hovering around freezing with periods of colder Arctic air dropping wind chills into the teens or single digits.
  • Recent cold snaps this month have already pushed temperatures below 0 °F on some days, so “how cold is it” can swing quickly from just-below-freezing to dangerously cold.

What It Feels Like Outside

  • With typical Chicago wind, the “feels like” temperature often comes in several degrees lower than the actual air temperature, especially near the lake.
  • When Arctic air masses move through, wind chills can fall well below 0 °F, which can cause frostbite on exposed skin in under 30 minutes.

How Today Compares To Normal

  • Historical December data show average daily temperatures near 30 °F overall, so anything in the teens or single digits counts as notably colder than normal.
  • This late-December period in 2025 is running on the colder side thanks to repeated shots of Arctic air, but not unprecedented for Chicago winters.

Quick Cold-Weather Tips

  • Wear layered clothing (base layer, insulating layer, windproof outer layer) and cover hands, ears, and face when wind chills drop into the teens or below.
  • Limit time outside during the coldest, windiest parts of the day, and watch for signs of numbness or tingling in fingers, toes, and nose.

Information gathered from public forums or data available on the internet and portrayed here.