Normal weather in May: Normal, Illinois: normal highs, lows, rain and records for May
Normal in May has a normal high of 74°F and a normal low of 50°F, a daily mean of 62°F, rising from 69°F on the 1st to 79°F by the 31st. Measurable precipitation falls on 12 days in a normal May, 4.81 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 23°C and low of 10°C, 122 mm of precipitation in May.
- NOAA stationNormal (4 mi NE)
- Station IDUSC00116200
- Location40.55°N 88.95°W
- Elevation790 ft (241 m)
- Population53,304
- Jan 33° 16°
- Feb 38° 19°
- Mar 50° 28°
- Apr 63° 38°
- May 74° 50°
- Jun 83° 60°
- Jul 86° 63°
- Aug 84° 61°
- Sep 79° 53°
- Oct 66° 42°
- Nov 50° 31°
- Dec 38° 21°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Normal in May?
The normal high is 74°F and the normal low 50°F, for a daily mean of 61.9°F. May is 11.6°F warmer than April and 9.7°F cooler than June. May is the 5th warmest month of the year in Normal and the wettest. Across the month the normal high rises 10°F, from 69°F on May 1 to 79°F on May 31. From one year to the next May's mean temperature typically moves about 3.5°F either way (NOAA's standard deviation), so roughly two Mays in three average between 58°F and 65°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 40%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| May 1 | 69°F | 44°F | 40% | 27% |
| May 8 | 71°F | 47°F | 40% | 27% |
| May 15 | 74°F | 50°F | 39% | 27% |
| May 22 | 76°F | 52°F | 38% | 26% |
| May 31 | 79°F | 55°F | 37% | 26% |
Every day of May: normal high, low and chance of precipitation (warmest afternoon May 31, coldest night May 1)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| May 1 | 69°F | 44°F | 40% | 27% | 13 h 50 min |
| May 2 | 69°F | 44°F | 40% | 27% | 14 h |
| May 3 | 70°F | 45°F | 40% | 27% | 14 h |
| May 4 | 70°F | 45°F | 40% | 27% | 14 h |
| May 5 | 70°F | 46°F | 40% | 27% | 14 h |
| May 6 | 71°F | 46°F | 40% | 27% | 14 h 10 min |
| May 7 | 71°F | 46°F | 40% | 27% | 14 h 10 min |
| May 8 | 71°F | 47°F | 40% | 27% | 14 h 10 min |
| May 9 | 72°F | 47°F | 40% | 27% | 14 h 10 min |
| May 10 | 72°F | 48°F | 40% | 27% | 14 h 10 min |
| May 11 | 72°F | 48°F | 40% | 27% | 14 h 20 min |
| May 12 | 73°F | 48°F | 40% | 27% | 14 h 20 min |
| May 13 | 73°F | 49°F | 40% | 27% | 14 h 20 min |
| May 14 | 73°F | 49°F | 39% | 27% | 14 h 20 min |
| May 15 | 74°F | 50°F | 39% | 27% | 14 h 20 min |
| May 16 | 74°F | 50°F | 39% | 27% | 14 h 30 min |
| May 17 | 74°F | 50°F | 39% | 27% | 14 h 30 min |
| May 18 | 75°F | 51°F | 39% | 27% | 14 h 30 min |
| May 19 | 75°F | 51°F | 39% | 27% | 14 h 30 min |
| May 20 | 75°F | 51°F | 38% | 26% | 14 h 30 min |
| May 21 | 76°F | 52°F | 38% | 26% | 14 h 40 min |
| May 22 | 76°F | 52°F | 38% | 26% | 14 h 40 min |
| May 23 | 77°F | 53°F | 38% | 26% | 14 h 40 min |
| May 24 | 77°F | 53°F | 38% | 26% | 14 h 40 min |
| May 25 | 77°F | 53°F | 38% | 26% | 14 h 40 min |
| May 26 | 78°F | 54°F | 38% | 26% | 14 h 40 min |
| May 27 | 78°F | 54°F | 37% | 26% | 14 h 40 min |
| May 28 | 78°F | 54°F | 37% | 26% | 14 h 50 min |
| May 29 | 79°F | 55°F | 37% | 26% | 14 h 50 min |
| May 30 | 79°F | 55°F | 37% | 26% | 14 h 50 min |
| May 31 | 79°F | 55°F | 37% | 26% | 14 h 50 min |
- Normal high
- 74°FMay average
- Normal low
- 50°FMay average
- Precipitation
- 4.81 inmonth total
- Days with precipitation
- 120.01 inch or more
- Days at 90°F or more
- 1
- Nights at 32°F or colder
- 1
- Daylight
- 13 h 50 min to 14 h 50 minMay 1 to May 31
- Days at 70°F or more
- 20
- Days at 80°F or more
- 11
- Sunshine
- 72%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USC00116200; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in Normal in May?
On a given May day the chance of 0.01 inch or more is 39% on average, highest around May 1 (40%). In all, 4.81 in falls on 12 days of a normal May, 1 of them with an inch or more.
In a normal May in Normal, 1 days reach 90°F and 1 nights fall to freezing.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USC00116200.
What are the records for May in Normal?
The warmest May temperature on this station's record (since 1893) is 103°F, on May 31, 1934; the coldest is 21°F, on May 10, 1966. The wettest May brought 10.17 in (1908).
The May mean against the 1991-2020 normal of 61.9°F: 2021 59.3°F (−2.6), 2022 63.5°F (+1.6), 2023 62.4°F (+0.5), 2024 65.3°F (+3.4), 2025 60.8°F (−1.1), 2026 60.7°F (−1.2). 3 of 6 ran warmer than normal.
| May | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 59.3°F | −2.6°F | 6.22 in |
| 2022 | 63.5°F | +1.6°F | 3.62 in |
| 2023 | 62.4°F | +0.5°F | 2.18 in |
| 2024 | 65.3°F | +3.4°F | 3.70 in |
| 2025 | 60.8°F | −1.1°F | 3.51 in |
| 2026 | 60.7°F | −1.2°F | 2.09 in |
Source: records: ACIS, station USC00116200; recent months: ACIS, station USC00116200. Records and recent months use complete months only.
How does May in Normal compare across Illinois?
Across the 144 places PlainClimate covers in Illinois, May normal highs run from 67°F in Waukegan to 79°F in Belleville; Normal's is 74°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.