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The temperatures in Chicago in August are comfortable with low of 19°C and and high up to 27°C.
You can expect about 3 to 8 days of rain in Chicago during the month of August. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Our weather forecast can give you a great sense of what weather to expect in Chicago in August 2025.
If you’re planning to visit Chicago in the near future, we highly recommend that you review the 14 day weather forecast for Chicago before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | -2° / -7° | 5 | 11 | 15 | 39 mm | Awful | Chicago in January |
| February | 0° / -6° | 4 | 11 | 14 | 41 mm | Awful | Chicago in February |
| March | 7° / 1° | 6 | 19 | 6 | 55 mm | Bad | Chicago in March |
| April | 12° / 5° | 7 | 21 | 3 | 79 mm | Awful | Chicago in April |
| May | 19° / 12° | 7 | 24 | 0 | 98 mm | Ok | Chicago in May |
| June | 24° / 17° | 7 | 23 | 0 | 128 mm | Good | Chicago in June |
| July | 27° / 20° | 7 | 24 | 0 | 114 mm | Good | Chicago in July |
| August | 27° / 19° | 5 | 26 | 0 | 100 mm | Perfect | Chicago in August |
| September | 24° / 16° | 4 | 26 | 0 | 64 mm | Perfect | Chicago in September |
| October | 16° / 10° | 5 | 25 | 0 | 65 mm | Good | Chicago in October |
| November | 9° / 3° | 4 | 22 | 4 | 40 mm | Bad | Chicago in November |
| December | 3° / -2° | 5 | 16 | 10 | 38 mm | Awful | Chicago in December |