Summer temperatures · Illinois
How hot does Chicago get in summer?
In a typical summer, June to August, Chicago averages highs around 83°F and lows around 64°F.
About 17 days a year reach 90°F or hotter, and a day at 100°F comes along less than once a year. About 82 days a year get to 80°F or warmer. That makes it the 58th coolest summer of the 129 US cities we track.
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The hottest high in the forecast for the next 48 hours is about 48°F.
Chicago’s summer highs average about 83°F, the city’s reward for winter highs around 35°F, and it plans to spend every degree of it at the lakefront.
Live 48-hour forecast from OpenWeatherMap, refreshed about every half hour. Alerts from the National Weather Service.
Summer at a glance
| Average summer high | 83°F |
|---|---|
| Average summer low | 64°F |
| Days a year at 80°F or warmer | 82 |
| Days a year at 90°F or hotter | 17 |
| Days a year at 100°F or hotter | fewer than one |
| Average winter high, for comparison | 35°F |
Summer here is June to August. Counts are averages a year.
Cities with about the same summer
- Toledo, Ohio: highs around 85°F, lows around 63°F
- Asheville, North Carolina: highs around 84°F, lows around 63°F
- Boise, Idaho: highs around 88°F, lows around 59°F
More about the weather here
Source: NOAA U.S. Climate Normals, 1991 to 2020, station USW00094846.