Boulder County (Boulder)
December
Weather in Boulder County for December 2025
Your guide to Boulder County weather in December - trends and predictions
In general, the average temperature in Boulder County at the beginning of December is 8.7 °F. As the month progressed, temperatures tended to noticeably cool down, reaching an average of 5.9 °F by the end of December.
Precipitation in Boulder County during December is a rare event, with an average of fewer than 2 rainy days.
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Temperatures
Rain 🌧️
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31
Dry days
0
Rainy days
0
Snow days
7°/-2°
Temperatures
20 km/h
Avg max wind
46 %
Avg humidity
Boulder County Weather December
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| Sun. | Mon. | Tue. | Wed. | Thu. | Fri. | Sat. |
|---|---|---|---|---|---|---|
| 1  8° | 2 7° | 3 11° | 4 6° | 5  8° | 6 9° | |
| 7 12° | 8  9° | 9  1° | 10 -3° | 11  4° | 12 6° | 13 5° |
| 14 11° | 15 8° | 16 6° | 17 6° | 18 7° | 19 7° | 20 12° |
| 21 12° | 22 13° | 23 9° | 24 9° | 25 8° | 26 7° | 27 6° |
| 28 5° | 29 9° | 30 6° | 31 0° |
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Temperatures trend during December in Boulder County
See the weather trend as well as the moving average line
December weather day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Dec. 1 | Sunny | 8° /0° | 0 mm | 3 | |
| Dec. 2 | Sunny | 7° /-3° | 0 mm | 3 | |
| Dec. 3 | Sunny | 11° /-2° | 0 mm | 4 | |
| Dec. 4 | Sunny | 6° /-1° | 0 mm | 3 | |
| Dec. 5 | Partly cloudy | 8° /-1° | 0 mm | 3 | |
| Dec. 6 | Sunny | 9° /-2° | 0 mm | 3 | |
| Dec. 7 | Sunny | 12° /-1° | 0 mm | 4 | |
| Dec. 8 | Overcast | 9° /1° | 0 mm | 2 | |
| Dec. 9 | Cloudy | 1° /-7° | 0 mm | 1 | |
| Dec. 10 | Sunny | -3° /-8° | 0 mm | 2 | |
| Dec. 11 | Patchy rain possible | 4° /-7° | 0.1 mm | 1 | |
| Dec. 12 | Overcast | 6° /-2° | 0 mm | 2 | |
| Dec. 13 | Overcast | 5° /0° | 0 mm | 1 | |
| Dec. 14 | Sunny | 11° /0° | 0 mm | 4 | |
| Dec. 15 | Sunny | 8° /-1° | 0 mm | 3 | |
| Dec. 16 | Sunny | 6° /-6° | 0 mm | 3 | |
| Dec. 17 | Cloudy | 6° /-1° | 0 mm | 2 | |
| Dec. 18 | Overcast | 7° /-3° | 0 mm | 2 | |
| Dec. 19 | Sunny | 7° /0° | 0 mm | 3 | |
| Dec. 20 | Partly cloudy | 12° /-1° | 0 mm | 4 | |
| Dec. 21 | Sunny | 12° /4° | 0 mm | 4 | |
| Dec. 22 | Overcast | 13° /3° | 0 mm | 3 | |
| Dec. 23 | Partly cloudy | 9° /2° | 0 mm | 3 | |
| Dec. 24 | Overcast | 9° /0° | 0 mm | 2 | |
| Dec. 25 | Overcast | 8° /0° | 0 mm | 2 | |
| Dec. 26 | Cloudy | 7° /-2° | 0 mm | 2 | |
| Dec. 27 | Overcast | 6° /1° | 0 mm | 2 | |
| Dec. 28 | Overcast | 5° /-2° | 0 mm | 2 | |
| Dec. 29 | Cloudy | 9° /1° | 0 mm | 2 | |
| Dec. 30 | Cloudy | 6° /-2° | 0 mm | 2 | |
| Dec. 31 | Cloudy | 0° /-6° | 0 mm | 1 | |
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Important Notice
Our weather forecast for Boulder County in December is based on the analysis of historical data rather than real-time forecast models. While this provides a general overview, weather conditions can change. We recommend that you check the Boulder County forecast closer to your planned date for the most up-to-date weather information.
Boulder County in December - FAQ
What are the expected maximum and minimum temperatures in Boulder County during December?
Prepare for cooler days with highs just around 7° and colder nights, dipping below -2°.
How much rainfall should be expected in Boulder County during December?
Rainfall in Boulder County during December is rare to nonexistent, with the total expected rainfall being less than 10 mm and approximately 0 days seeing any precipitation. Planning without the concern for rain is generally straightforward during this very dry period.
Will it snow in Boulder County in December 2025?
Boulder County typically sees 0 cm of snowfall during December.
What are the typical wind conditions in Boulder County during December?
The average wind speed in Boulder County during December is 20 km/h, suggesting breezy to windy conditions, depending on your activities.
December rainfall patterns in Boulder County
Explore the daily rainfall trends and prepare for Boulder Countys December weather 💧
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