Castle Rock weather in December: Castle Rock, Colorado: normal highs, lows, rain and records for December
Castle Rock in December has a normal high of 46°F and a normal low of 18°F, a daily mean of 32°F, falling from 48°F on the 1st to 45°F by the 31st. Measurable precipitation falls on 5 days in a normal December, 0.69 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 8°C and low of −8°C, 18 mm of precipitation and 23 cm of snow in December.
- NOAA stationCastle Rock
- Station IDUSC00051401
- Location39.41°N 104.91°W
- Elevation6,185 ft (1,885 m)
- Population83,213
- Jan 46° 18°
- Feb 47° 20°
- Mar 54° 27°
- Apr 59° 33°
- May 68° 42°
- Jun 80° 51°
- Jul 86° 56°
- Aug 84° 55°
- Sep 77° 47°
- Oct 65° 35°
- Nov 54° 26°
- Dec 46° 18°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Castle Rock in December?
The normal high is 46°F and the normal low 18°F, for a daily mean of 31.8°F. December is 8.0°F cooler than November and 0.0°F cooler than January. December is the 11th warmest month of the year in Castle Rock and the 11th wettest. Across the month the normal high falls 3°F, from 48°F on December 1 to 45°F on December 31. From one year to the next December's mean temperature typically moves about 2.7°F either way (NOAA's standard deviation), so roughly two Decembers in three average between 29°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 15%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| December 1 | 48°F | 21°F | 15% | 8% |
| December 8 | 46°F | 19°F | 15% | 8% |
| December 15 | 45°F | 18°F | 15% | 8% |
| December 22 | 45°F | 17°F | 15% | 7% |
| December 31 | 45°F | 17°F | 14% | 7% |
Every day of December: normal high, low and chance of precipitation (warmest afternoon December 1, coldest night December 22)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| December 1 | 48°F | 21°F | 15% | 8% | 9 h 40 min |
| December 2 | 48°F | 20°F | 15% | 8% | 9 h 40 min |
| December 3 | 48°F | 20°F | 15% | 8% | 9 h 30 min |
| December 4 | 47°F | 20°F | 15% | 8% | 9 h 30 min |
| December 5 | 47°F | 20°F | 15% | 8% | 9 h 30 min |
| December 6 | 47°F | 19°F | 15% | 8% | 9 h 30 min |
| December 7 | 47°F | 19°F | 15% | 8% | 9 h 30 min |
| December 8 | 46°F | 19°F | 15% | 8% | 9 h 30 min |
| December 9 | 46°F | 19°F | 15% | 8% | 9 h 30 min |
| December 10 | 46°F | 18°F | 15% | 8% | 9 h 30 min |
| December 11 | 46°F | 18°F | 15% | 8% | 9 h 30 min |
| December 12 | 46°F | 18°F | 15% | 8% | 9 h 30 min |
| December 13 | 45°F | 18°F | 15% | 8% | 9 h 30 min |
| December 14 | 45°F | 18°F | 15% | 8% | 9 h 30 min |
| December 15 | 45°F | 18°F | 15% | 8% | 9 h 20 min |
| December 16 | 45°F | 17°F | 15% | 8% | 9 h 20 min |
| December 17 | 45°F | 17°F | 15% | 8% | 9 h 20 min |
| December 18 | 45°F | 17°F | 15% | 8% | 9 h 20 min |
| December 19 | 45°F | 17°F | 15% | 8% | 9 h 20 min |
| December 20 | 45°F | 17°F | 15% | 8% | 9 h 20 min |
| December 21 | 45°F | 17°F | 15% | 8% | 9 h 20 min |
| December 22 | 45°F | 17°F | 15% | 7% | 9 h 20 min |
| December 23 | 45°F | 17°F | 15% | 7% | 9 h 20 min |
| December 24 | 45°F | 17°F | 15% | 7% | 9 h 20 min |
| December 25 | 45°F | 17°F | 15% | 7% | 9 h 20 min |
| December 26 | 45°F | 17°F | 15% | 7% | 9 h 20 min |
| December 27 | 45°F | 17°F | 14% | 7% | 9 h 20 min |
| December 28 | 45°F | 17°F | 14% | 7% | 9 h 20 min |
| December 29 | 45°F | 17°F | 14% | 7% | 9 h 20 min |
| December 30 | 45°F | 17°F | 14% | 7% | 9 h 30 min |
| December 31 | 45°F | 17°F | 14% | 7% | 9 h 30 min |
- Normal high
- 46°FDecember average
- Normal low
- 18°FDecember average
- Precipitation
- 0.69 inmonth total
- Days with precipitation
- 50.01 inch or more
- Snowfall
- 8.9 inmonth total
- Nights at 32°F or colder
- 29
- Daylight
- 9 h 40 min to 9 h 30 minDecember 1 to December 31
- Sunshine
- 79%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USC00051401; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain or snow in Castle Rock in December?
On a given December day the chance of 0.01 inch or more is 15% on average, highest around December 14 (15%). In all, 0.69 in falls on 5 days of a normal December.
In a normal December in Castle Rock, 29 nights fall to freezing, 4 days stay below freezing all day and snowfall averages 8.9 inches.
Snow falls on 4 days in a normal December, and an inch or more covers the ground on 11 days.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USC00051401.
What are the records for December in Castle Rock?
The warmest December temperature on this station's record (since 1893) is 82°F, on December 3, 2021; the coldest is −29°F, on December 31, 1900. The wettest December brought 5.35 in (1913); the snowiest, 43.5 inches (1913).
The December mean against the 1991-2020 normal of 31.8°F: 2021 45.5°F (+13.7), 2022 30.6°F (−1.2), 2023 35.6°F (+3.8), 2024 38.7°F (+6.9). 3 of 4 ran warmer than normal.
| December | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 45.5°F | +13.7°F | 0.09 in |
| 2022 | 30.6°F | −1.2°F | 1.18 in |
| 2023 | 35.6°F | +3.8°F | 1.02 in |
| 2024 | 38.7°F | +6.9°F | 0.24 in |
Source: records: ACIS, station USC00051401; recent months: ACIS, station USC00051401. Records and recent months use complete months only.
How does December in Castle Rock compare across Colorado?
Across the 125 places PlainClimate covers in Colorado, December normal highs run from 27°F in Crested Butte to 49°F in Campo; Castle Rock's is 46°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.
Other months and places
- Castle Rock in November54°F by day, 26°F at night
- Castle Rock in January46°F by day, 18°F at night
- Castle Rock through the yearEvery month, frost dates, records and recent years
- Colorado in DecemberThe statewide normal and the warmest and coolest places
- Campo: Colorado's warmest Decembernormal high 49°F