Best time to visit Chicago

Re-score for me — drag the dial — every chart on the page recolours live for your heat limit 27°C
I'm comfortable up to 27°C feels-like
22° heat-averse 30° heat-loving

Default 27 °C is the upper edge of the Holiday Climate Index "ideal comfort" band (Scott, Rutty, Amelung & Tang, 2016). Above this, most warm-tourism travellers report measurable discomfort.

Saved to this browser. Changes update the strips below.
Recent · 2020-2024
Interest Google Trends 2021-2025 searches, not arrivals (?)
Day · avg daily high (?)
Night · avg overnight low (?)
Heatwaves · days/yr ≥35°C ETCCDI TX35 (?)
<11
Tropical nights · nights/yr ≥20°C ETCCDI TR20 — sleep killer (?)
<1712112
UV index · On a typical day around midday, UV is about this (?)
123567775321
On the sunniest 1 in 10 days, UV reaches this — and even higher
3789975
PM2.5 air quality · on a typical day (?)
1013111114191513118910
On the worst 1 in 10 days, PM2.5 reaches this — and even higher
172119162531222017131617
September 9/10 feels 23°C (+2°C vs 1991-2020) · HCI 88/100
Day 24° · Night 16° 60% humidity 24 km/h wind 8 rain days (88h) 217h sun
Thermal 9
Sky 9
Rain 8
Wind 9

Higher = better, including rain & wind (green = "doesn't hurt the score", not "lots of it").

How is this scored? HCI / Steadman / CCI gate — full methodology and citations below.

Compare with another destination

Add as many as you like — stacked below the main strips above. Each row is just the recent-window score strip and (for beach destinations) sea-temperature strip.

Tours in Chicago

24 top-rated tours via Viator. Booking links earn this site a commission at no cost to you.

  1. 1Chicago River 90-Minute Architecture Boat Tour4.84★ (1,652)1h 30mfrom $37🔥 Selling fast
  2. 2Chicago City Minibus Tour4.91★ (572)2hfrom $50🔥 Selling fast
  3. 3Chicago Murder Mystery Tour4.98★ (738)2hfrom $35🔥 Selling fast
  4. 4Chicago River 90-Minute Architecture Tour4.71★ (10,017)1h 30mfrom $45🔥 Selling fast
  5. 5Chicago River 45-Minute Architecture Tour from Magnificent Mile4.66★ (3,195)45mfrom $28🔥 Selling fast
  6. 6Lake Michigan Sunset Cruise in Chicago4.53★ (1,548)1h 30mfrom $45🔥 Selling fast
  7. 7Chicago Lake and River Architecture Tour4.69★ (2,333)1h 30mfrom $45🔥 Selling fast
  8. 8Chicago City Tour with Architecture River Cruise Option4.77★ (719)from $50🔥 Selling fast
  9. 9Chicago Small Group City Tour5.00★ (1)from $415🔥 Selling fast
  10. 10Luxury Minibus Chicago City Tour4.83★ (6)2hfrom $65🔥 Selling fast
  11. 11Chicago Craft Brewery Barrel Bus Tour4.86★ (348)3h 45mfrom $100🔥 Selling fast
  12. 12Chicago's Ultimate City Bike Tour of Top Downtown Attractions4.93★ (245)3hfrom $59🔥 Selling fast
  13. 13Chicago Architecture River Cruise4.84★ (16,085)from $39
  14. 14Chicago Favorites Ultimate Food and Walking Tour4.85★ (2,081)3hfrom $85
  15. 15Chicago in a Day Walking Tour: Food, History & Architecture4.92★ (1,233)4h 30mfrom $101
  16. 16Chicago's Chinatown Food and Walking Tour4.92★ (672)3hfrom $80
  17. 17Original Chicago Architecture Interiors Tour: Dazzling Interiors4.96★ (1,619)2hfrom $35
  18. 18Chicago Bike & Classic Food Tour: Bikes, Bites & Views - Adults4.95★ (739)4h 30mfrom $89
  19. 19Chicago Food Tour: 6 Dishes with Deep Dish Pizza & Beef Sandwich4.91★ (911)3hfrom $85
  20. 20Skip-the-line: Art Institute of Chicago Guided Tour4.97★ (500)2h 30mfrom $84
  21. 21Delicious Donuts & City Sights: Chicago's Original Donut Tour4.94★ (1,419)2hfrom $70
  22. 22Medieval Torture Museum Ticket with Audio Guide and Ghost Hunting4.85★ (1,027)1h 30mfrom $51
  23. 23Chicago Crime and Mob Bus Tour4.60★ (3,314)from $42
  24. 24Trickery Chicago Magic Show4.85★ (101)from $41🔥 Selling fast

Last refreshed 2026-05-25.

Similar climatesToronto93% · Niagara Falls92% · Boston92%

Other destinations with the most-alike year-round climate to Chicago (apparent temperature, rain hours, sunshine — matched within the same trip-profile). The ±N chip compares each match's typical score for the current month against Chicago's. Based on the 2020-2024 climatology, not this year's actual weather.

Month-by-month

Month Temp °C Feels °C Rain days Rain h Rain h/day Humidity Wind km/h Sun h UV Interest Score
Jan -6–1 -5 11 152 13.8 73% 26 102 1 Quiet 3
Feb -6–3 -3 9 103 11.4 67% 28 153 2 Quiet 5
Mar 0–9 4 12 119 9.9 66% 29 177 3 Quiet 5
Apr 4–14 9 15 139 9.3 62% 28 198 5 Quiet 5
May 10–19 17 11 119 10.8 64% 25 238 6 Quiet 7
Jun 17–26 26 10 95 9.5 57% 25 265 7 Quiet 9
Jul 19–27 28 12 124 10.3 65% 22 271 7 Quiet 7
Aug 19–27 28 11 101 9.2 62% 22 270 7 Peak 8
Sep 16–24 23 8 88 11.0 60% 24 217 5 Busy 9
Oct 9–17 14 12 135 11.3 61% 27 181 3 Moderate 7
Nov 3–10 6 7 77 11.0 64% 26 144 2 Peak 6
Dec -2–4 -1 9 97 10.8 70% 25 108 1 Busy 4

UV Index in Chicago by Month

UV index in Chicago peaks at 7 (high) in June, dropping to 1 (low) in December. May, June, July, August have high UV — SPF 30+ and sunglasses recommended.

Best months in detail

September

9/10

16–24°C (feels 23°C) · 8 rain days (88h) · 217 sun hours · 60% humidity · Busy crowd · UV 5 (moderate) · sunniest 1 in 10 days reach 7 (high)

June

9/10

17–26°C · 10 rain days (95h) · 265 sun hours · 57% humidity · Quiet crowd · UV 7 (high) · sunniest 1 in 10 days reach 9 (very high)

August

8/10

19–27°C · 11 rain days (101h) · 270 sun hours · 62% humidity · Peak crowd · UV 7 (high)

Every month

Show the other 9 months in detail

January

3/10

-6–1°C (feels -5°C) · 11 rain days (152h) · 102 sun hours · 73% humidity · Quiet crowd · UV 1 (low)

February

5/10

-6–3°C (feels -3°C) · 9 rain days (103h) · 153 sun hours · 67% humidity · Quiet crowd · UV 2 (low) · sunniest 1 in 10 days reach 3 (moderate)

March

5/10

0–9°C (feels 4°C) · 12 rain days (119h) · 177 sun hours · 66% humidity · Quiet crowd · UV 3 (moderate)

April

5/10

4–14°C (feels 9°C) · 15 rain days (139h) · 198 sun hours · 62% humidity · Quiet crowd · UV 5 (moderate) · sunniest 1 in 10 days reach 7 (high)

May

7/10

10–19°C (feels 17°C) · 11 rain days (119h) · 238 sun hours · 64% humidity · Quiet crowd · UV 6 (high) · sunniest 1 in 10 days reach 8 (high)

July

7/10

19–27°C (feels 28°C) · 12 rain days (124h) · 271 sun hours · 65% humidity · Quiet crowd · UV 7 (high) · sunniest 1 in 10 days reach 9 (very high)

October

7/10

9–17°C (feels 14°C) · 12 rain days (135h) · 181 sun hours · 61% humidity · Moderate crowd · UV 3 (moderate) · sunniest 1 in 10 days reach 5 (moderate)

November

6/10

3–10°C (feels 6°C) · 7 rain days (77h) · 144 sun hours · 64% humidity · Peak crowd · UV 2 (low)

December

4/10

-2–4°C (feels -1°C) · 9 rain days (97h) · 108 sun hours · 70% humidity · Busy crowd · UV 1 (low)

Comparisons people search for

Pairs validated by Google Autocomplete demand — only pairs people actually compare.

Frequently asked questions about visiting Chicago

When is the best time to visit Chicago?

September is the highest-scoring month (9/10 on the Holiday Climate Index). Typical conditions: 16–24°C (8 rainy days). The top three months by score are September, June, August.

What is the worst time to visit Chicago?

January is the lowest-scoring month (3/10). Typical conditions: -6–1°C (11 rainy days).

When are crowds lowest in Chicago?

Search-interest seasonality (Google Trends 2021-2025) is lowest in April and peaks in August. Interest tracks both in-trip visitors and lead-time planners, so treat it as a "destination is on people's minds" signal rather than literal arrivals.

Which months in Chicago have good weather but fewer tourists?

June (climate 9/10, crowd index 7) and May (climate 7/10, crowd index 4) — shoulder months with above-average climate and below-median search-interest. Often the best value-for-weather trade.

What is the UV index in Chicago by month?

UV peaks at 7 (high) in June and is lowest in December at 1 (low). Monthly peak values: Jan 1, Feb 2, Mar 3, Apr 5, May 6, Jun 7, Jul 7, Aug 7, Sep 5, Oct 3, Nov 2, Dec 1.

What is the UV index in Chicago in June?

June is the peak UV month in Chicago, with a daily-peak UV index of 7 (high). Apply SPF 30+, wear sunglasses, and seek shade during midday hours.

How high can UV get in Chicago on the sunniest days?

Most days look like the monthly average, but on the sunniest ~1 in 10 days UV climbs higher than the mean suggests. June is the worst case: typical days average UV 7 (high), but the top 10% of days reach UV 9 (very high) — and even higher. Months where the sunniest days routinely exceed the typical reading: February, April, May, June, July, September, October. Plan sun protection for the worst case, not the average.

Is air quality in Chicago bad for travelers?

PM2.5 (fine-particle pollution) exceeds the WHO sensitive-group guideline (15 µg/m³) in 11 months: January, February, March, April, May, June, July, August, September, November, December. The worst month is June with a typical-day mean of 19 µg/m³ (unhealthy for sensitive); on the worst 10% of days PM2.5 reaches 31 µg/m³ (unhealthy) and higher. People with asthma, heart conditions, or sensitive children may want to avoid these months or limit outdoor activity. Source: CAMS via Open-Meteo.