Chicago weather in January
Long-run climate averages for Chicago, IL in January, plus what the forecast models say for the days ahead.
In January, Chicago averages 34°F by day and 23°F at night. The wettest month is usually July.
January in Chicago averages a daytime high of 34°F and an overnight low of 23°F, which reads as cold for this part of the world. It is the coldest month of the year here. Overnight temperatures drop below freezing, so expect frost and pack accordingly. Across the whole year Chicago sees roughly 45 inches of precipitation.
Climate averages tell you what to pack. They do not tell you what next Tuesday looks like - for that, see the live Chicago forecast with every model compared and how much they currently agree.
Chicago weather by month
what to expect in Chicago through the yearHere is Chicago's typical weather in each month: the average daytime high and overnight low in °F, how each month feels, and the wettest month marked. Use it to plan any trip to Chicago by season.
Bottom line: over the last 30 days the European model has been the most accurate forecast for Chicago, scoring 89/100 on our CheckWeather Score, ahead of the American at 68. See the full US accuracy scoreboard for exactly how every model is tested.
Common questions
How warm is Chicago in January?
Is January a good time to visit Chicago?
Does it rain a lot in Chicago in January?
Climate averages from ERA5 reanalysis. Model accuracy re-scored over a rolling 30 days. Page updated .