If you're looking for summer vibes, the best time to travel to Waukegan is in July, June and August, when the average temperature reaches 22.29 °C, while July, September and May are the 3 sunniest months of the year, with an average of 142.9 hours.
However, if you prefer colder temperatures, make sure you visit Waukegan during January, February or March to experience an average of -3.5 °C.
For those who don't care too much about temperatures, but want to avoid getting wet in the rain, it's important to avoid travelling during January, February and March, when the average precipitation in Waukegan is 7.5 mm, while the months of January, February and March are drier, with an average of 0 mm.