What to expect in Chicago in August
August is a strong choice for Chicago: 28° / 17°, with the biggest crowds of the year and premium prices.
Chicago weather in August
Typical conditions in Chicago during August, based on long-run climate normals rather than any single year. Treat it as a planning guide, not a forecast.
| Average high | 28°C 82°F |
|---|---|
| Average low | 17°C 63°F |
| Rainfall | Wet 56/100 |
| Total rainfall | 125 mm4.9 in |
| Rainy days | 10 |
| Daylight | 13 h 52 min |
| How it feels | Warm and comfortable |
Average highs sit around 28°C with lows near 17°C. Rainfall is moderate; the odd shower is likely.
Crowds & demand
Crowd levels are High for Chicago — the biggest crowds of the year.
Prices & value
This month counts as high season: premium prices.
What to pack
Light layers for 28°C days and something with sleeves for evenings, which cool to around 17°C. Add a compact rain shell and shoes you do not mind soaking; this is one of the wetter months.
What it costs
This is peak pricing for Chicago. Expect to pay a premium on flights and accommodation, and to book considerably further ahead than usual. Compared with the most expensive month of the year, you are looking at roughly 2% less.
Who this month suits
- Travellers who want the most reliable weather
- Visitors who want to catch a festival
- Families tied to school holidays
Events & what’s on
Look out for Chicago Air and Water Show while you’re there.
- Chicago Air and Water Show — A free air show held since 1959 over the Lake Michigan shore each August.
Chicago in August compared with nearby months
If your dates are flexible by a few weeks, this is what shifting them actually buys you.
| Month | Temp | Crowds | Price | Score |
|---|---|---|---|---|
| June | 27° / 15° | High | $$$ | 48 |
| July | 29° / 18° | High | $$$ | 40 |
| August · This month | 28° / 17° | High | $$$ | 42 |
| September | 24° / 12° | High | $$ | 57 |
| October | 17° / 6° | Moderate | $$ | 53 |
These months score higher for Chicago on the same blend of weather, crowds and price. Same destination, better odds.
Or go somewhere else in August
If the destination is negotiable but the month is not, these places are at their best in August.
Figures are climate normals and modelled estimates — a planning guide, not a forecast. We separate fact, estimate and recommendation. Updated October 2026
