Chicago in May
In May, Chicago has 114.0 mm (4.49 in) of rain, a daily high of 21.4 °C (70.5 °F) and a daily low of 10.3 °C (50.5 °F), as 1991-2020 means; figures in brackets are converted.
Last updated : what the month is like; shorter source notes.
Best time to visit Chicago: May meets our rule. Expect days that grow by 57 min.
What May is like in Chicago
- Buckingham Fountain wakes up in early May. For twenty minutes each hour, its center jet throws water up to one hundred fifty feet high. Source: Choose Chicago (official tourism site), checked .
- Polka bands strike up and steins of beer are raised at Maifest, a yearly German gathering in Lincoln Square in May. Source: Choose Chicago (official tourism site), checked .
- Beach season opens on the lakefront on the Friday before Memorial Day. Surfers paddle out at Montrose Beach until Labor Day. Source: Chicago Park District, checked .
- Green City Market moves outdoors to Lincoln Park in May, on Saturdays and Wednesdays. Locals line up there for fresh crepes and smoothies. Source: Choose Chicago (official tourism site), checked .
Key figures
Weather in May, 1991-2020 means
- Daily high
- 21.4 °C (70.5 °F)
- Daily low
- 10.3 °C (50.5 °F)
- Rain
- 114.0 mm (4.49 in) in the month
- Sunshine
- no data
U.S. Climate Normals 1991-2020, NOAA. Checked .
Measured at Chicago O'Hare International Airport, 28 km north-west of the city centre point.
How we define and convert these figures
Notes. Daily high and low: changed: source gives °F; converted to °C, rounded to 0.1. Rain: changed: source gives inches; converted to mm (x 25.4), rounded to 0.1. Sunshine: the NOAA U.S. monthly normals have no sunshine measure.
Daylight on 15 May 2026
- Sunrise
- 05:30 local time
- Sunset
- 20:04 local time
- Day length
- 14 h 34 min
Day length 1-31 May: 14 h 03 min to 15 h 00 min, +57 min.
Source: NOAA Solar Calculator equations, checked .
Month by month
Each month: daily high in °C, then rain in mm, 1991-2020 means.
NOAA U.S. Climate Normals 1991-2020, as above, checked .
This month against the year
| Measure | May | Rank |
|---|---|---|
| Daily high | 21.4 °C | 5th warmest |
| Daily low | 10.3 °C | 5th warmest |
| Rain | 114.0 mm | wettest |
| Sunshine | no data | no data |
| Day length | 14 h 34 min | 3rd longest |
Equal values share a rank. How we rank months
NOAA U.S. Climate Normals 1991-2020, as above, checked .
Day length: NOAA solar equations, checked .
Public holidays this month
| Date | Holiday |
|---|---|
| Monday | Memorial Day opm.gov |
| Date | Holiday |
|---|---|
| Monday | Memorial Day opm.gov |
Typed from the official list and re-checked, .
Source: Official public holiday list (cms.illinois.gov), checked .
Same month in 20 cities
Chicago is warmer than 8 of our 20 cities in May by mean daily high. How we rank cities
Closest high and low in May: Vienna (0.6 °C apart), Paris (1.0), Berlin (1.4, equal), Buenos Aires (1.4, equal), Prague (1.4, equal).
| City | Gap from Chicago, °C | High, °C | Low, °C | Rain, mm | Sunshine, hours |
|---|---|---|---|---|---|
| Chicago (this page) | — | 21.4 | 10.3 | 114.0 | no data |
| Vienna (closest) | 0.6 | 20.7 | 10.7 | 78.9 | 248.3 |
| Paris (closest) | 1.0 | 20.2 | 11.1 | 69.0 | 201.0 |
| Berlin (closest) | 1.4 | 19.6 | 9.3 | 52.3 | 224.3 |
| Buenos Aires (closest) | 1.4 | 19.4 | 11.1 | 93.5 | 157.4 |
| Prague (closest) | 1.4 | 20.1 | 8.9 | 67.0 | 221.5 |
| Munich | 1.5 | 19.4 | 9.3 | 107.0 | 213.0 |
| New York | 1.5 | 21.9 | 12.8 | 100.6 | no data |
| London | 1.8 | 18.4 | 9.7 | 44.7 | no data |
| Madrid | 1.9 | 23.5 | 11.9 | 48.3 | no data |
| Rome | 2.2 | 23.4 | 12.6 | no data | no data |
| Barcelona | 2.6 | 22.2 | 14.7 | 41.9 | 240.7 |
| Amsterdam | 2.7 | 17.8 | 8.6 | 53.9 | 230.7 |
| Los Angeles | 3.0 | 23.2 | 14.5 | 8.1 | no data |
| Tokyo | 3.3 | 23.6 | 14.6 | 139.7 | 179.6 |
| Hiroshima | 3.9 | 24.4 | 15.1 | 169.8 | 210.8 |
| Osaka | 4.6 | 24.9 | 16.0 | 136.5 | 203.7 |
| Seville | 5.4 | 27.8 | 14.7 | 33.9 | 324.9 |
| Hong Kong | 10.8 | 28.8 | 24.5 | 290.6 | 138.8 |
| Singapore | 13.2 | 32.3 | 25.7 | 164.3 | no data |
Sources (1991-2020): WMO climate normals and NOAA U.S. Climate Normals, checked , ; Hong Kong: our 1991-2020 mean of the Hong Kong Observatory daily climate series on DATA.GOV.HK; Singapore: our 1991-2020 mean of the National Environment Agency monthly climate series on data.gov.sg; both checked . Each city's page names its station. All sources in full on Methodology.
Hong Kong figures: The Government of the Hong Kong Special Administrative Region and the Hong Kong Observatory own the intellectual property rights in the data; attribution to them and DATA.GOV.HK. Licence: Terms and Conditions of Use of DATA.GOV.HK, version 1.2.
Singapore figures: Contains information from the National Environment Agency on data.gov.sg, made available under the terms of the Singapore Open Data Licence version 1.0 (https://data.gov.sg/open-data-licence). The Agency does not endorse our means.
Sources
- Attribution: Palecki, Michael; Durre, Imke; Applequist, Scott; Arguez, Anthony; Lawrimore, Jay (2021). U.S. Climate Normals 2020: U.S. Monthly Climate Normals (1991-2020). Station files named in each record. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/wck8-er13. Accessed on the check date shown. Licence: No licence stated; citation requested. Checked .
- NOAA Solar Calculator equations, computed locally, NOAA Global Monitoring Laboratory (method); City by Month (computation). Attribution: Computed with the NOAA Solar Calculator method (no NOAA endorsement implied). Licence: Method, not data. Checked .
Official sources
Cite this page: City by Month. "Chicago in May: weather, daylight, holidays". https://citybymonth.com/cities/united-states/chicago/may/. Last updated 5 November 2026.