Chicago Weather in August
During August, Chicago experiences high daytime temperatures of 28°C (82°F) and cooler nights around 18°C (64°F). Expect quite a bit of rainfall. Around 115 mm (4.5 in) is typical.
Rainfall in Chicago in August
Typically around 11 days of rainfall are expected, averaging 115 mm (4.5 in) for the month. When showers do arrive, they tend to be on the heavier side. Worth being prepared even if rain days are not that numerous.
Temperature in Chicago in August
August in Chicago sees highs of 28°C (82°F) and lows of 18°C (64°F) overnight. This gives the month a fairly typical daily rhythm, with warmer afternoons and more comfortable nights. With lows of 18°C (64°F), nights are cool. If you're out after dark, an extra layer will keep you comfortable. The cooler air at night is also great for getting a good rest.
Sunshine in Chicago in August
Expect a lot of sunshine this month, with about 280 hours of sun. These sunny conditions add to the overall experience.
Wind Speed in Chicago in August
August sees wind speeds averaging 4 m/s (8 knots). You'll experience variable conditions with moderate winds that create small waves on water and keep branches moving. Conditions range from light winds to moderate breezes throughout the month.If you prefer dry days with pleasant temperatures, September typically offers the best circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United States of America, check out our Chicago's climate page.
Chicago Temperature in August
Min Temperature
18°C (64°F)
Max Temperature
28°C (82°F)
Chance of Rain
37%
Precipitation
115 mm (4.5 in)
Rainy days
11 days
Humidity
71%
Windspeed
4 m/s (8 knots)
Sunshine
280 hours
Percentage Sunshine
66%
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Chicago typically stay consistent throughout August, with daily highs averaging around 28°C (82°F). Nights are pleasant, with lows typically ranging from 17°C (63°F) to 19°C (66°F).
Average temperatures in August
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in August
Historical weather for Chicago in August
Browse day-by-day weather records for Chicago spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Chicago historical weather extremes in August
Based on 49 years of weather observations in Chicago between 1976 and 2025, these are the recorded extremes.
- The warmest day in August was on August 2, 1991, with a maximum of 38°C (100°F).
- Chicago experienced its chilliest August day on August 25, 1987, reaching only 16°C (61°F).
- The lowest overnight temperature recorded in August was 6°C (43°F) (August 28, 1986).
Best Places in the United States of America in August
Find out more about the weather in the United States of America and which places have the best travel conditions in this month. See all of the United States of America in August →
perfect weather
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What to Wear in Chicago in August
Warm weather calls for comfortable, breathable clothing in August. Cotton t-shirts, shorts, light dresses, and sandals are perfect. You might still want a light layer for evenings or air-conditioned places (for example buses). High rain levels are expected, so pack waterproof gear and an umbrella or poncho. Don't forget sun protection, sunglasses, sunscreen, and a hat. These are all good ideas with this much sunshine.What To Do in Chicago in August
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United States of America, check out our Chicago's climate page.
Temperature Rainfall Sunshine Humidity Wind Speed
See the full Chicago climate overview or explore weather in the United States of America.
