San Bernardino
December
Weather in San Bernardino for December 2025
Your guide to San Bernardino weather in December - trends and predictions
In general, the average temperature in San Bernardino at the beginning of December is 21.6 °F. As the month progressed, temperatures tended to significantly cool down, reaching an average of 16 °F by the end of December.
San Bernardino experiences moderate rainfall in December, with an average of 6 rainy days and a total precipitation of 39.1 mm.
New! Chat with our AI weatherman - it’s amazing and free.
Temperatures
Rain 🌧️
More
25
Dry days
6
Rainy days
0
Snow days
18°/9°
Temperatures
8 km/h
Avg max wind
41 %
Avg humidity
San Bernardino in December average weather
Move between months or click on a day
| Sun. | Mon. | Tue. | Wed. | Thu. | Fri. | Sat. |
|---|---|---|---|---|---|---|
| 1  20° | 2 20° | 3 21° | 4  22° | 5 24° | 6 23° | |
| 7  21° | 8 19° | 9 20° | 10 22° | 11 19° | 12 14° | 13 15° |
| 14 16° | 15 20° | 16 21° | 17 21° | 18  20° | 19  20° | 20 19° |
| 21  18° | 22  16° | 23 18° | 24 15° | 25 15° | 26 15° | 27 15° |
| 28 19° | 29 18° | 30 15° | 31 15° |
You can click on date
Access San Bernardino weather forecasts with a simple click. Select any date for comprehensive insights on temperature, rainfall, and wind conditions.
Temperatures trend during December in San Bernardino
See the weather trend as well as the moving average line
December weather day by day
Click on a date for more information
| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| Dec. 1 | Sunny | 20° /9° | 0 mm | 6 | |
| Dec. 2 | Sunny | 20° /6° | 0 mm | 5 | |
| Dec. 3 | Sunny | 21° /8° | 0 mm | 5 | |
| Dec. 4 | Overcast | 22° /11° | 0 mm | 6 | |
| Dec. 5 | Sunny | 24° /9° | 0 mm | 7 | |
| Dec. 6 | Sunny | 23° /11° | 0 mm | 6 | |
| Dec. 7 | Partly cloudy | 21° /9° | 0 mm | 6 | |
| Dec. 8 | Sunny | 19° /9° | 0 mm | 6 | |
| Dec. 9 | Sunny | 20° /8° | 0 mm | 6 | |
| Dec. 10 | Sunny | 22° /6° | 0 mm | 6 | |
| Dec. 11 | Overcast | 19° /9° | 0 mm | 5 | |
| Dec. 12 | Sunny | 14° /7° | 0 mm | 5 | |
| Dec. 13 | Sunny | 15° /5° | 0 mm | 5 | |
| Dec. 14 | Partly cloudy | 16° /7° | 0 mm | 4 | |
| Dec. 15 | Partly cloudy | 20° /5° | 0 mm | 6 | |
| Dec. 16 | Sunny | 21° /9° | 0 mm | 6 | |
| Dec. 17 | Overcast | 21° /9° | 0 mm | 6 | |
| Dec. 18 | Cloudy | 20° /10° | 0 mm | 5 | |
| Dec. 19 | Light rain shower | 20° /11° | 3.4 mm | 5 | |
| Dec. 20 | Light rain shower | 19° /10° | 5.5 mm | 5 | |
| Dec. 21 | Patchy light rain with thunder | 18° /9° | 2.6 mm | 5 | |
| Dec. 22 | Light rain | 16° /9° | 1.9 mm | 4 | |
| Dec. 23 | Sunny | 18° /7° | 0 mm | 6 | |
| Dec. 24 | Overcast | 15° /9° | 2.1 mm | 4 | |
| Dec. 25 | Partly cloudy | 15° /5° | 0 mm | 5 | |
| Dec. 26 | Partly cloudy | 15° /7° | 0 mm | 4 | |
| Dec. 27 | Overcast | 15° /6° | 0 mm | 4 | |
| Dec. 28 | Cloudy | 19° /7° | 0 mm | 5 | |
| Dec. 29 | Overcast | 18° /9° | 0 mm | 5 | |
| Dec. 30 | Light rain shower | 15° /7° | 4 mm | 4 | |
| Dec. 31 | Light rain shower | 15° /8° | 2.1 mm | 4 | |
| Next | |||||
Important Notice
Our weather forecast for San Bernardino 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 San Bernardino forecast closer to your planned date for the most up-to-date weather information.
San Bernardino in December - FAQ
What are the expected maximum and minimum temperatures in San Bernardino during December?
Enjoy moderate daytime temperatures of up to 18° and cooler nights around 9°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in San Bernardino during December?
In December, San Bernardino can expect light to moderate rainfall, totaling 39.1 mm across approximately 6 days. Occasional showers are possible, and planning ahead for them could be helpful.
What are the typical wind conditions in San Bernardino during December?
The average wind speed in San Bernardino during December is 8 km/h, suggesting breezy to windy conditions, depending on your activities.
December rainfall patterns in San Bernardino
Explore the daily rainfall trends and prepare for San Bernardinos December weather 💧
UV exposure in San Bernardino during December
Stay informed about UV levels for safe outdoor activities throughout the month of December ☀️
Quick links
You are here
Where is San Bernardino?Get accurate weather forecasts for San Bernardino, located at latitude 34.108 and longitude -117.29. Stay updated with localized weather information tailored for San Bernardino.
Found a mistake?
We appreciate your attention to details. Tell us here.