Normal weather in December: Normal, Illinois: normal highs, lows, rain and records for December
Normal in December has a normal high of 38°F and a normal low of 21°F, a daily mean of 30°F, falling from 43°F on the 1st to 34°F by the 31st. Measurable precipitation falls on 9 days in a normal December, 2.30 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 3°C and low of −6°C, 58 mm of precipitation and 9 cm of snow in December.
- 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 December?
The normal high is 38°F and the normal low 21°F, for a daily mean of 29.8°F. December is 10.7°F cooler than November and 5.3°F warmer than January. December is the 10th warmest month of the year in Normal and the 11th wettest. Across the month the normal high falls 9°F, from 43°F on December 1 to 34°F on December 31. From one year to the next December's mean temperature typically moves about 4.7°F either way (NOAA's standard deviation), so roughly two Decembers in three average between 25°F and 35°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 29%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| December 1 | 43°F | 25°F | 29% | 19% |
| December 8 | 41°F | 23°F | 29% | 19% |
| December 15 | 38°F | 22°F | 29% | 19% |
| December 22 | 36°F | 20°F | 29% | 19% |
| December 31 | 34°F | 18°F | 29% | 19% |
Every day of December: normal high, low and chance of precipitation (warmest afternoon December 1, coldest night December 31)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| December 1 | 43°F | 25°F | 29% | 19% | 9 h 30 min |
| December 2 | 43°F | 25°F | 29% | 19% | 9 h 30 min |
| December 3 | 43°F | 25°F | 29% | 19% | 9 h 30 min |
| December 4 | 42°F | 24°F | 29% | 19% | 9 h 30 min |
| December 5 | 42°F | 24°F | 29% | 19% | 9 h 30 min |
| December 6 | 41°F | 24°F | 29% | 19% | 9 h 20 min |
| December 7 | 41°F | 24°F | 29% | 19% | 9 h 20 min |
| December 8 | 41°F | 23°F | 29% | 19% | 9 h 20 min |
| December 9 | 40°F | 23°F | 29% | 19% | 9 h 20 min |
| December 10 | 40°F | 23°F | 29% | 19% | 9 h 20 min |
| December 11 | 40°F | 23°F | 29% | 19% | 9 h 20 min |
| December 12 | 39°F | 22°F | 29% | 19% | 9 h 20 min |
| December 13 | 39°F | 22°F | 29% | 19% | 9 h 20 min |
| December 14 | 39°F | 22°F | 29% | 19% | 9 h 20 min |
| December 15 | 38°F | 22°F | 29% | 19% | 9 h 20 min |
| December 16 | 38°F | 21°F | 29% | 19% | 9 h 20 min |
| December 17 | 38°F | 21°F | 29% | 19% | 9 h 20 min |
| December 18 | 37°F | 21°F | 29% | 19% | 9 h 20 min |
| December 19 | 37°F | 21°F | 29% | 19% | 9 h 20 min |
| December 20 | 37°F | 20°F | 29% | 19% | 9 h 20 min |
| December 21 | 37°F | 20°F | 29% | 19% | 9 h 20 min |
| December 22 | 36°F | 20°F | 29% | 19% | 9 h 20 min |
| December 23 | 36°F | 20°F | 29% | 19% | 9 h 20 min |
| December 24 | 36°F | 19°F | 29% | 19% | 9 h 20 min |
| December 25 | 36°F | 19°F | 29% | 19% | 9 h 20 min |
| December 26 | 35°F | 19°F | 29% | 19% | 9 h 20 min |
| December 27 | 35°F | 19°F | 29% | 19% | 9 h 20 min |
| December 28 | 35°F | 19°F | 29% | 19% | 9 h 20 min |
| December 29 | 35°F | 18°F | 29% | 19% | 9 h 20 min |
| December 30 | 35°F | 18°F | 29% | 19% | 9 h 20 min |
| December 31 | 34°F | 18°F | 29% | 19% | 9 h 20 min |
- Normal high
- 38°FDecember average
- Normal low
- 21°FDecember average
- Precipitation
- 2.30 inmonth total
- Days with precipitation
- 90.01 inch or more
- Snowfall
- 3.6 inmonth total
- Nights at 32°F or colder
- 27
- Daylight
- 9 h 30 min to 9 h 20 minDecember 1 to December 31
- Sunshine
- 62%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 or snow in Normal in December?
On a given December day the chance of 0.01 inch or more is 29% on average, highest around December 1 (29%). In all, 2.30 in falls on 9 days of a normal December.
In a normal December in Normal, 27 nights fall to freezing, 10 days stay below freezing all day and snowfall averages 3.6 inches.
Snow falls on 3 days in a normal December, and an inch or more covers the ground on 7 days.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USC00116200.
What are the records for December in Normal?
The warmest December temperature on this station's record (since 1893) is 72°F, on December 4, 2012; the coldest is −22°F, on December 23, 1989. The wettest December brought 7.62 in (1895); the snowiest, 20.9 inches (1973).
The December mean against the 1991-2020 normal of 29.8°F: 2021 37.7°F (+7.9), 2022 28.2°F (−1.6), 2023 38.3°F (+8.5), 2024 32.0°F (+2.2), 2025 27.6°F (−2.2). 3 of 5 ran warmer than normal.
| December | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 37.7°F | +7.9°F | 2.30 in |
| 2022 | 28.2°F | −1.6°F | 2.62 in |
| 2023 | 38.3°F | +8.5°F | 2.71 in |
| 2024 | 32.0°F | +2.2°F | 2.32 in |
| 2025 | 27.6°F | −2.2°F | 1.42 in |
Source: records: ACIS, station USC00116200; recent months: ACIS, station USC00116200. Records and recent months use complete months only.
How does December in Normal compare across Illinois?
Across the 144 places PlainClimate covers in Illinois, December normal highs run from 33°F in Galena to 48°F in Anna; Normal's is 38°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.