The biggest temperature swing occurs between October and November, with a change of 7°C.
| Month | Low Temperature | High Temperature | Category |
|---|---|---|---|
| January | | | cold |
| February | | | cold |
| March | | | cold |
| April | | | cool |
| May | | | mild |
| June | | | warm |
| July | | | warm |
| August | | | warm |
| September | | | warm |
| October | | | mild |
| November | | | cool |
| December | | | cold |
⚠️ High UV Alert: April, May, June, July, August, September require serious sun protection.
Daylight varies from 9.2 hours in December (winter) to 15.2 hours in June (summer), which is a difference of 6 hours.
Northern Hemisphere seasons shape the weather patterns throughout the year. Here's what to expect in each season:
Click any month for detailed weather information and packing advice.
Get personalized month rankings based on weather comfort, outdoor activity suitability, and seasonal conditions.
View Best Time to VisitThe best months to visit Chicago depend on your preferences. For warm weather, July is typically the warmest month. For dry conditions, February, December, January tend to have the least rainfall. Consider your priorities—whether you prefer warmer temperatures, drier weather, or longer daylight hours.
July is typically the warmest month in Chicago, with average high temperatures reaching around 27°C (81°F). This is peak summer weather, ideal for outdoor activities and sightseeing.
January is usually the coldest month, with average low temperatures dropping to around -8°C (18°F). Pack warm layers if visiting during this time, especially for evening activities.
May typically sees the most rainfall in Chicago, averaging around 117mm (4.6 inches). It's wise to pack waterproof layers and have some indoor backup plans if you're visiting during this month.
February is typically the driest month, with average rainfall of just 57mm (2.2 inches). This makes it an excellent time for outdoor exploration and activities with minimal risk of rain disruption.
Temperatures in Chicago range from average lows of 7°C (44°F) to highs of 14°C (57°F). This variation means you'll want to pack differently depending on when you visit—layers are key for adapting to the seasonal changes.
Yes, sun protection is important in Chicago. UV levels can reach 8 during peak months, which is considered high. Pack sunscreen (SPF 30+), sunglasses, and a hat, especially if you'll be outdoors for extended periods.