Cook County Weather in May
Average highs run from 49°F on May 1 to 57°F on May 31, and lows from 34°F to 41°F. Normal precipitation for the month is 2.61 in over about 9 wet days.
May day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
May at a glance
- Average high
- 53°F
- Average low
- 37°F
- Precipitation
- 2.61 in
- Record high
- 86°FMay 31, 2002
- Record low
- 24°FMay 3, 2005
- Chance of a freeze
- 93%
- Daylight
- 14 h 31 min to 15 h 44 min
- Cloud cover
- 66%
- Humidity
- 73%
- Dew point
- 39°F
- Wind
- 7.2 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.
| Date | Normal high | Normal low | Record high | Record low | Chance wet | Chance of snow |
|---|---|---|---|---|---|---|
| May 1 | 49°F | 34°F | 73°F 2021 | 28°F 2003 | 25% | |
| May 2 | 49°F | 34°F | 70°F 2020 | 26°F 2003 | 25% | |
| May 3 | 50°F | 34°F | 74°F 2015 | 24°F 2005 | 26% | |
| May 4 | 50°F | 34°F | 75°F 2018 | 29°F 2022 | 26% | |
| May 5 | 50°F | 35°F | 60°F 1999 | 27°F 2004 | 26% | |
| May 6 | 51°F | 35°F | 81°F 2025 | 30°F 2006 | 26% | |
| May 7 | 51°F | 35°F | 71°F 2000 | 27°F 2020 | 27% | |
| May 8 | 51°F | 36°F | 61°F 2000 | 25°F 2020 | 27% | |
| May 9 | 52°F | 36°F | 80°F 2025 | 25°F 2020 | 27% | |
| May 10 | 52°F | 36°F | 83°F 2007 | 29°F 2020 | 27% | |
| May 11 | 52°F | 36°F | 68°F 2024 | 28°F 2018 | 28% | |
| May 12 | 53°F | 37°F | 78°F 2024 | 28°F 2020 | 28% | |
| May 13 | 53°F | 37°F | 74°F 2003 | 27°F 2020 | 28% | |
| May 14 | 53°F | 37°F | 65°F 2008 | 29°F 2016 | 29% | |
| May 15 | 53°F | 37°F | 81°F 2013 | 29°F 2016 | 29% | |
| May 16 | 54°F | 38°F | 73°F 2006 | 31°F 2014 | 29% | |
| May 17 | 54°F | 38°F | 68°F 2001 | 28°F 2002 | 29% | 0% |
| May 18 | 54°F | 38°F | 72°F 2001 | 27°F 2002 | 29% | 0% |
| May 19 | 54°F | 38°F | 62°F 2012 | 29°F 2002 | 30% | 0% |
| May 20 | 55°F | 39°F | 74°F 2023 | 26°F 2002 | 30% | 0% |
| May 21 | 55°F | 39°F | 81°F 2016 | 29°F 2002 | 30% | 0% |
| May 22 | 55°F | 39°F | 72°F 2021 | 32°F 2006 | 30% | 0% |
| May 23 | 55°F | 39°F | 72°F 2000 | 33°F 2013 | 31% | 0% |
| May 24 | 56°F | 39°F | 69°F 2000 | 32°F 2002 | 31% | 0% |
| May 25 | 56°F | 40°F | 69°F 2021 | 34°F 2011 | 31% | 0% |
| May 26 | 56°F | 40°F | 85°F 2014 | 32°F 2011 | 31% | 0% |
| May 27 | 56°F | 40°F | 81°F 1999 | 31°F 2011 | 32% | 0% |
| May 28 | 57°F | 40°F | 74°F 2003 | 32°F 2021 | 32% | 0% |
| May 29 | 57°F | 40°F | 70°F 2025 | 30°F 2021 | 32% | 0% |
| May 30 | 57°F | 41°F | 85°F 2006 | 33°F 2015 | 32% | 0% |
| May 31 | 57°F | 41°F | 86°F 2002 | 31°F 2015 | 33% | 0% |
Chance of rain
- Chance of a wet day
- Chance of snowfall
Sunrise and sunset
Times for 2026, local time (CDT).
- May 1
- sunrise 5:44 AM, sunset 8:15 PM
- May 31
- sunrise 5:08 AM, sunset 8:52 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00213282 (Grand Marais), public domain. Records: NOAA GHCN-Daily, station USW00094992, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.