Measured, not vibes
Best Time to Visit Chicago
By measured weather comfort, the top months for Chicago are September, May, June — and RouteVerdict's editorial pick, which also weighs crowds and prices, is May, June, July, August, September, October. The table below is computed from ERA5 reanalysis data for 2020–2024, measured at Chicago (179 m elevation).
Month by month
Chicago weather and comfort, 2020–2024
| Month | Avg high | Wet days | Comfort | Season |
|---|---|---|---|---|
| January | 0.9°C / 34°F | 8.5 | 4 | |
| February | 2.9°C / 37°F | 7 | 7 | |
| March | 9.3°C / 49°F | 9 | 26 | |
| April | 14.2°C / 58°F | 12 | 47 | Shoulder |
| May | 19.9°C / 68°F | 9.8 | 76 | Best |
| June | 26.9°C / 80°F | 9.5 | 74 | Best |
| July | 27.5°C / 82°F | 9.7 | 71 | |
| August | 27.4°C / 81°F | 8.7 | 73 | |
| September | 24.2°C / 76°F | 7.2 | 85 | Best |
| October | 17.3°C / 63°F | 10.5 | 65 | |
| November | 10.5°C / 51°F | 5.3 | 34 | Shoulder |
| December | 4.7°C / 40°F | 7.3 | 11 |
Comfort is RouteVerdict's 0–100 score: 100·exp(−(high−23)²/162) × (1 − min(0.35, wet days × 0.02)). The full method is on the methodology page. Weather data by Open-Meteo.com (ERA5, CC BY 4.0), 2020–2024 normals. Wet day = ≥1 mm precipitation.
What the seasons are actually like
Traveling to Chicago month by month
Chicago's comfort score peaks in September at 84.8, with an average high of 24.2°C and just 7.2 wet days, ahead of May's 75.8 and June's 73.7. RouteVerdict's editorial pick spans May through October — the full warm season — even though July and August, at comfort scores of 71.1 and 73.3, trail both May and September. Winter is severe: January averages just 0.9°C with a comfort score of 4.1, the lowest of any month, and December isn't far behind at 10.8. April sits just outside the editorial window, with a comfort score of 47.1, well below May's 75.8.
FAQ
Chicago timing questions
What is the best month to visit Chicago?
By measured weather comfort (ERA5 2020–2024), the top months are September, May, and June, with September scoring highest. RouteVerdict's editorial pick is May, June, July, August, September, and October, which also weighs crowds, prices, and events.
What is the hottest month in Chicago?
July, with an average daily high of 27.5°C (82°F).
What is the rainiest month in Chicago?
April, averaging 12 days with at least 1 mm of precipitation.
When is shoulder season in Chicago?
April and November — the best-scoring months outside both the measured top three and RouteVerdict's editorial peak-season pick.
Why does Chicago's editorial pick include July and August if May and September score higher?
July and August score 71.1 and 73.3 on comfort, a step below May's 75.8 and September's 84.8, but RouteVerdict's editorial pick spans the full May-through-October warm season rather than just the top two months.
What is Chicago's coldest month?
January, averaging just 0.9°C with a comfort score of 4.1 — the lowest of any month.