December Weather in Fort Collins, United States

Last updated: February 24, 2025

In Fort Collins, United States, December temperatures exhibit a striking contrast, with a maximum of 22°C (72°F) providing occasional warmth against an average low of -16°C (3°F). The month is characterized by a chilly ambiance, as the average temperature hovers around 1°C (33°F). December also brings 16 mm (0.6 in) of precipitation over just 3 days, adding a slight touch of moisture to the crisp air, which is often accompanied by high humidity levels reaching 85%. This combination creates a unique winter landscape, perfect for those who enjoy the enchanting blend of sunlit days and the crispness of cold nights.

December Temperature in Fort Collins

As December arrives in Fort Collins, the chilly embrace of winter becomes unmistakable, with minimum temperatures hovering around -16°C (3°F). A stark contrast to the mild autumn months, the average temperature settles at a brisk 1°C (33°F), while daytime highs can reach a pleasant 22°C (72°F), offering a welcome respite from the cold. This pattern highlights the significant drop in temperature as the year draws to a close, setting the stage for a cozy holiday atmosphere. The warmth of the peak temperatures belies the more frigid nighttime conditions, reflecting the region's characteristic temperature swings that define its winter charm. December serves as the transition into the heart of winter, where enchanting snow-covered landscapes invite both residents and visitors to embrace outdoor activities and festive cheer.

December Weather in Fort Collins: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Fort Collins, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec302940475568747265484033
Data source: Temperature data for Fort Collins generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in Fort Collins

In December, Fort Collins experiences a decline in precipitation, receiving an average of 16 mm (0.6 in) over the month, which translates to just 3 days of rainfall. This marks a noticeable drop compared to the wetter months preceding it, such as May, which sees the highest average at 116 mm (4.6 in). The trend throughout the year shows a significant increase in precipitation during the spring, peaking in May, followed by a gradual reduction as winter settles in. As temperatures drop, the combination of shorter days and lower moisture levels results in less frequent rainfall. December's relatively dry conditions hint at the onset of winter, setting the stage for the colder, drier months ahead.

December Precipitation Trends in Fort Collins

The chart displays monthly precipitation patterns in Fort Collins, with values for each month alongside December's data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how December's conditions compare to those of other months.
JanFebMarAprMayJunJulAugSepOctNovDec1723535311640303726362116
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
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December Humidity in Fort Collins

In December, Fort Collins experiences a noticeable uptick in humidity, reaching a level of 85%—matching the humidity of February. This increase marks a return to the higher humidity levels characteristic of the winter months, as seen in January and November, both of which hover around the mid-80s. Throughout the year, humidity levels generally decline from March to July, with the summer months enjoying some of the lowest readings, between 62% and 68%. However, as autumn approaches, humidity begins to rise again, culminating in a winter that brings a cozy, moist air reminiscent of the early year. Overall, this trend illustrates how Fort Collins transitions from dryer summers into a more humid winter, providing a comfortable chill that underscores its seasonal character.

December Average Humidity in Fort Collins

This chart illustrates the average monthly humidity levels in Fort Collins, with December's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how December's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec84%86%75%67%67%68%62%63%63%72%80%85%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Fort Collins

As December rolls into Fort Collins, the UV Index sits at a pleasant 3, categorized as moderate. This marks a decline from the extreme levels seen in the summer months, providing a breath of fresh air after the intense sun exposure of late spring and summer. December’s “burn time” efficiently stretches back to 30 minutes, reminiscent of January, highlighting a seasonal shift towards safer sun exposure. This trend reflects a natural ebb and flow in UV intensity throughout the year, making it essential for residents and visitors to stay informed about changing conditions. For more detailed insights, check out Fort Collins UV Index.

Maximum UV Index Levels in Fort Collins for December

The chart shows the monthly maximum UV Index (UVI) for Fort Collins in December, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec46811111212119643
Data source: Fort Collins December UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

December Sunshine in Fort Collins

As December unfolds in Fort Collins, the city basks in an inviting 237 hours of sunshine, a delightful embrace that brings a gentle end to the year. While this amount is a dip from the sun-drenched peak of 382 hours in July, it still outshines the winter gloom typical of many regions. The trend from January to December showcases a steady climb, peaking in the vibrant summer months, before tapering off in the chilly end of the year. December's sunshine, while less than the sunnier months, bathes the landscape in a soft glow, offering a comforting respite amid the colder temperatures and hinting at the promise of brighter days ahead.

Monthly Sunshine Duration in Fort Collins: December Highlighted

The December sunshine duration represents the total number of hours Fort Collins experiences direct sunlight during the month of December, excluding cloudy or obstructed periods. This chart compares the sunshine duration of December with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec185h234h285h300h327h374h382h352h306h272h248h237h
Data source: Fort Collins December Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Fort Collins During December

In Fort Collins, December boasts a 66% chance of sunny weather, continuing a trend of relatively bright months as the year wraps up. This figure reflects an upward trajectory in sunshine, especially noticeable when comparing the early winter months to those in the spring, where chances hover around the low 50s. As we move from the cooler months of November to December, residents can expect a notable increase in sunshine, which contrasts sharply with the cloudier days of late fall. Overall, December's sunny prospects suggest a delightful final stretch of the year, making it an inviting time for outdoor activities and festivities under the clear Colorado sky.

Percentage of Sunny Days in December in Fort Collins

The chart illustrates the percentage of sunny days in Fort Collins throughout the year, with December highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Fort Collins experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec56%49%50%51%39%57%62%66%69%65%62%66%
Data source: Fort Collins December chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Fort Collins in December

As December rolls into Fort Collins, sunlight wanes to a modest 9 hours of daylight, mirroring the twilight of November. This month marks the end of a gradual descent, where daylight duration decreased from a lively 15 hours in June down to the year’s lowest point. The winter’s embrace contrasts starkly with the vibrant 14 hours of daylight in May, showcasing the significant seasonal shifts in this Colorado locale. The consistent decline from the peak of summer hours sets the stage for shorter, darker days, as the community prepares for the cozy warmth of indoor gatherings and festive celebrations. As we approach the winter solstice, the cycle renews, promising brighter days ahead in the new year.

Average Daylight Hours in Fort Collins for December

The chart illustrates the variation in daylight duration in Fort Collins throughout the year, with December highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 38m10h 40m11h 58m13h 19m14h 26m15h14h 41m13h 41m12h 24m11h 4m9h 54m9h 19m
Data source: Fort Collins daylight hours, calculated by summing the hours between sunrise and sunset for each day.

December Winds in Fort Collins

In December, Fort Collins experiences a average wind speed of 2.4 m/s (5 mph), mirroring the gentle breezes of many months prior. This consistency highlights a notable trend: the wind speeds remain fairly stable throughout the year, with only slight variations. Notably, the peak during April at 2.7 m/s (6 mph) introduces a brief uptick, while July showcases the calmest wind conditions at 2.1 m/s (5 mph). Overall, December's winds reflect the tranquil atmosphere of the season, combining with the crisp winter air to enhance the charm of the city during this festive month.

Average December Wind Speed in Fort Collins

The chart displays monthly wind speed patterns in Fort Collins, with values for each month shown alongside December's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how December's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec2.42.52.42.72.32.32.12.42.42.52.42.4 m/s
Data source: Fort Collins December wind data, generated using information from the Copernicus Climate Change Service.

How December Weather in Fort Collins Compares to Other Months

The weather in Fort Collins changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of December's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Fort Collins and find detailed weather information for every month.

December and January present strikingly different weather patterns. In December, temperatures range from a minimum of -16°C (3°F) to a maximum of 22°C (72°F), with an average around 1°C (33°F). The month experiences about 16 mm (0.6 in) of precipitation over 3 days, coupled with a relatively high humidity of 85%. In contrast, January tends to be colder, with temperatures dropping to a minimum of -26°C (-14°F), an average of -1°C (30°F), and a maximum of 17°C (62°F). Precipitation slightly increases to 17 mm (0.7 in) over 4 days, while humidity remains similar at 84%. For a more detailed look at January's weather, you can reference Fort Collins weather in January.

December and February exhibit notable differences in weather conditions. In December, temperatures range from a chilly minimum of -16°C (3°F) to a mild maximum of 22°C (72°F), with an average of 1°C (33°F). The month sees relatively low precipitation, totaling 16 mm (0.6 in) over just 3 days and maintaining a high humidity level of 85%. In contrast, February experiences even colder temperatures, with a minimum of -25°C (-13°F) and an average of -2°C (29°F), although it can peak at a warmer 24°C (75°F). Precipitation rises to 23 mm (0.9 in) and occurs over 6 days, yet humidity remains constant at 85%. For more detailed information, check out Fort Collins weather in February.

In December, temperatures typically range from a chilly minimum of -16°C (3°F) to a milder maximum of 22°C (72°F), with an average temperature of around 1°C (33°F). The month experiences limited precipitation, totaling 16 mm (0.6 in) over just 3 days, and maintains high humidity levels at 85%. In contrast, March presents a slightly broader temperature range, with minimums dipping to -21°C (-5°F) and highs reaching up to 26°C (79°F). The average temperature rises to 4°C (40°F), but March sees significantly higher precipitation, accumulating 53 mm (2.1 in) across 9 days, along with lower humidity at 75%. For more details on the weather patterns typical of this month, check out Fort Collins weather in March.

In December, temperatures can vary significantly, with lows reaching -16°C (3°F) and highs peaking at 22°C (72°F), while the average hovers around 1°C (33°F). The month features relatively low precipitation at 16 mm (0.6 in) across just 3 days, but the humidity remains high at 85%. In contrast, April offers a milder climate with a minimum temperature of -13°C (9°F) and a maximum of 29°C (85°F), resulting in an average of 8°C (47°F). This spring month experiences more rainfall, accumulating 53 mm (2.1 in) over 10 days, along with a decrease in humidity to 67%. For more details on the weather in April, you can check Fort Collins weather in April.

December weather is characterized by a cold embrace, with temperatures ranging from a chilling minimum of -16°C (3°F) to a mild maximum of 22°C (72°F) and an average hovering around 1°C (33°F). The month sees limited precipitation on about three days, while the high humidity of 85% adds to the overall damp and frigid atmosphere. In contrast, May offers a more temperate climate, with temperatures stretching from a minimum of -3°C (27°F) to a warm maximum of 31°C (88°F) and an average of 13°C (56°F). However, May experiences significantly higher precipitation, totaling 116 mm (4.6 in) over 14 days, while humidity drops to a more comfortable 67%. For a deeper dive into the weather specifics during this month, check out Fort Collins weather in May.

December and June present strikingly different weather conditions. In December, temperatures can plummet as low as -16°C (3°F) with an average of just 1°C (33°F), while the month may also see a maximum of 22°C (72°F). The humidity is quite high at 85%, and precipitation is minimal, averaging 16 mm across just 3 days. In contrast, June boasts more temperate weather with minimum temperatures around 5°C (41°F) and an average rise to 20°C (68°F), potentially reaching a sizzling maximum of 38°C (100°F). This month experiences more precipitation, totaling 40 mm over 8 days, while humidity levels drop to 68%. For a more detailed look at weather patterns, check out Fort Collins weather in June.

December and July present contrasting weather conditions. In December, temperatures can drop as low as -16°C (3°F), with an average of 1°C (33°F) and occasional highs reaching 22°C (72°F). The month sees about 16 mm (0.6 in) of precipitation over just 3 days, accompanied by high humidity levels of 85%. Conversely, July is significantly warmer, with temperatures ranging from a minimum of 9°C (49°F) to an average of 23°C (74°F), and peaks hitting 37°C (99°F). Precipitation increases slightly to 30 mm (1.2 in) over 6 days, but humidity is lower at 62%. For a closer look at July weather, visit Fort Collins weather in July.

The weather in December and August presents a stark contrast in Fort Collins. December typically experiences chilly temperatures, with a minimum of -16°C (3°F) and an average of 1°C (33°F), while August boasts much warmer conditions, featuring a minimum of 10°C (50°F) and an average of 22°C (72°F). Precipitation is also more prominent in August, with 37 mm (1.5 in) over about six days, compared to just 16 mm (0.6 in) in December across three days. Additionally, humidity levels in December are higher at 85%, creating a damp, cold environment, whereas August enjoys a more comfortable 63% humidity. For more details, check out Fort Collins weather in August.

December and September present contrasting weather patterns. In December, temperatures can drop significantly, with a minimum of -16°C (3°F) and an average of around 1°C (33°F), while the maximum reaches a milder 22°C (72°F). Meanwhile, September enjoys a much warmer climate with temperatures ranging from a minimum of -1°C (31°F) to a maximum of 37°C (99°F) and an average of 19°C (66°F). Precipitation is also more prevalent in September, with 26 mm (1.0 in) over four days compared to December's 16 mm (0.6 in) over just three days. Humidity levels in December are higher at 85%, whereas September sees a more comfortable 63%. For more detailed information, you can check Fort Collins weather in September.

In comparing the weather of October and December, one can observe notable differences in temperature and precipitation patterns. October typically experiences milder conditions with an average temperature of 9°C (49°F) and peaks reaching up to 29°C (84°F), while December has a much cooler average of 1°C (33°F) and can even drop to a chilling -16°C (3°F). Additionally, October has more humidity at 72% compared to December’s 85%, contributing to a relatively warmer feel despite the lower minimum temperatures. Precipitation is also more prevalent in October, with 36 mm (1.4 in) over 7 days, compared to December's 16 mm (0.6 in) spread across only 3 days. For further details on October weather, you can check Fort Collins weather in October.

December weather is characterized by a slightly wider temperature range compared to November, with minimum temperatures dropping to -16°C (3°F) and maximum temperatures reaching 22°C (72°F). On the other hand, November tends to be a bit warmer overall, with an average temperature of 4°C (40°F) and maximums up to 25°C (77°F). Precipitation is slightly lower in December at 16 mm (0.6 in) over 3 days, compared to November's 21 mm (0.8 in) spread over 5 days. Humidity levels are higher in December at 85%, compared to 79% in November, making the latter a bit more comfortable. For a more detailed look at November's climate, visit Fort Collins weather in November.

Compare Fort Collins's Climate with Cities Worldwide

Conclusion: What to Expect From December Weather in Fort Collins

In December, Fort Collins experiences a stark shift from the milder months of the year, bringing a unique blend of chilly temperatures and occasional precipitation. While the average temperature hovers around 1°C, residents can see extremes that dip as low as -16°C, contrasting sharply with the warmer autumn months. The higher humidity levels at 85% can make the cold feel even more biting, but with just a few days of precipitation, December offers glimpses of sunshine amidst its frosty charm. As the city transitions into winter, this month sets the stage for a cozy atmosphere, often encouraging residents and visitors alike to embrace outdoor activities while layering up. For more insights on Fort Collins’ yearly temperature patterns and weather nuances, check out Fort Collins Climate.