What's the weather like in Chicago in October?Located in the Midwest state of Illinois alongside Lake Michigan, Chicago is a popular and vibrant city with a humid continental climate. This brings changeable weather to the city at this time of year. In October, Chicago can be quite cold with temperatures dropping as the month goes on, although warmer spells are not uncommon. Many days are cloudy and windy, but the sun usually still finds time to shine through.
AveragesAt the start of October, temperatures in Chicago reach around 20°C in the hottest part of the day, falling to a low of 9°C at night. By the end of the month, lows reach a chilly 4°C so you’ll need to wrap up warm. This time of year can still be quite bright and sunny, although there are around 13 wet days expected, bringing 65mm of rain to the city. Snow and fog are quite rare in October.